chlorophyll-a and protochlorophyll

chlorophyll-a has been researched along with protochlorophyll* in 44 studies

Reviews

2 review(s) available for chlorophyll-a and protochlorophyll

ArticleYear
Photoactive pigment-enzyme complexes of chlorophyll precursor in plant leaves.
    Biochemistry. Biokhimiia, 2007, Volume: 72, Issue:13

    This review summarizes contemporary data on structure and function of photoactive pigment--enzyme complexes of the chlorophyll precursor that undergoes photochemical transformation to chlorophyllide. The properties and functions of the complex and its principal components are considered including the pigment (protochlorophyllide), the hydrogen donor (NADPH), and the photoenzyme protochlorophyllide oxidoreductase (POR) that catalyzes the photochemical production of chlorophyllide. Chemical variants of the chlorophyll precursor are described (protochlorophyllide, protochlorophyll, and their mono- and divinyl forms). The nature and photochemical activity of spectrally distinct native protochlorophyllide forms are discussed. Data are presented on structural organization of the photoenzyme POR, its substrate specificity, localization in etioplasts, and heterogeneity. The significance of different POR forms (PORA, PORB, and PORC) in adaptation of chlorophyll biosynthesis to various illumination conditions is considered. Attention is paid to structural and functional interactions of three main constituents of the photoactive complex and to possible existence of additional components associated with the pigment-enzyme complex. Historical aspects of the problem and the prospects of further investigations are outlined.

    Topics: Chlorophyll; Escherichia coli; Flavins; Models, Chemical; Molecular Conformation; Oxidoreductases Acting on CH-CH Group Donors; Pigmentation; Plant Leaves; Plant Proteins; Plants; Protein Conformation; Protein Structure, Secondary; Protochlorophyllide; Substrate Specificity; Temperature

2007
The biosynthesis of porphyrins, chlorophylls, and vitamin B12.
    Natural product reports, 1985, Volume: 2, Issue:6

    Topics: 5-Aminolevulinate Synthetase; Aminolevulinic Acid; Animals; Bile Pigments; Bilirubin; Biliverdine; Chlorophyll; Chlorophyllides; Cytochromes; Ferrochelatase; Heme; Hydroxymethylbilane Synthase; Metalloporphyrins; Metalloproteins; Nickel; Nucleotides; Oxidoreductases; Oxidoreductases Acting on CH-CH Group Donors; Plants; Porphobilinogen Synthase; Porphyrins; Protoporphyrinogen Oxidase; Uroporphyrinogen Decarboxylase; Uroporphyrinogen III Synthetase; Vitamin B 12

1985

Other Studies

42 other study(ies) available for chlorophyll-a and protochlorophyll

ArticleYear
Regulation of chlorophyll biosynthesis by light-dependent acetylation of NADPH:protochlorophyll oxidoreductase A in Arabidopsis.
    Plant science : an international journal of experimental plant biology, 2023, Volume: 330

    Chlorophylls are the major pigments that harvest light energy during photosynthesis in plants. Although reactions in chlorophyll biogenesis have been largely known, little attention has been paid to the post-translational regulation mechanism of this process. In this study, we found that four lysine sites (K128/340/350/390) of NADPH:protochlorophyllide oxidoreductase A (PORA), which catalyzes the only light-triggered step in chlorophyll biosynthesis, were acetylated after dark-grown seedlings transferred to light via acetylomics analysis. Etiolated seedlings with K390 mutation of PORA had a lower greening rate and decreased PORA acetylation after illumination. Importantly, K390 of PORA was found extremely conserved in plants and cyanobacteria via bioinformatics analysis. We further demonstrated that the acetylation level of PORA was increased by exposing the dark-grown seedlings to the histone deacetylase (HDAC) inhibitor TSA. Thus, the HDACs probably regulate the acetylation of PORA, thereby controlling this non-histone substrate to catalyze the reduction of Pchlide to produce chlorophyllide, which provides a novel regulatory mechanism by which the plant actively tunes chlorophyll biosynthesis during the conversion from skotomorphogenesis to photomorphogenesis.

    Topics: Acetylation; Arabidopsis; Arabidopsis Proteins; Chlorophyll; Light; NADP; Oxidoreductases; Oxidoreductases Acting on CH-CH Group Donors; Protochlorophyllide

2023
Protochlorophylls in Cucurbitaceae - Distribution, biosynthesis and phylogeny.
    Phytochemistry, 2022, Volume: 197

    Using high-resolution chromatography we resolved monovinyl (MV)- and divinyl (DV)-protochlorophylls (Pchls) and detected all of their side-chain homologues in the inner seed coat of Cucurbita maxima, C. pepo and their varieties. Furthermore, we analyzed other less common representatives of the Cucurbitaceae family that were found to accumulate mostly MV-Pchls. All these species and varieties showed the characteristic composition of individual Pchls. Additionally, we also detected all of the corresponding protopheophytins, which accounted for between 1.1 and 35.5% of Pchls and are supposed to be degradation products of Pchls, formed during seed storage. A pigment composition analysis of C. maxima seedlings performed during deetiolation revealed that chlorophyll (Chl) a content increased gradually, while the levels of Pchl-GG and Chl-GG, a precursor of Chl a, were low and did not change significantly. However, when the seedlings were incubated with the precursor of tetrapyrrole biosynthesis (δ-aminolevulinic acid) before illumination, the Chl-GG content increased dramatically, while synthesis of Chl a was inhibited. These data indicate that in C. maxima seedlings, Chl a is not synthesized from geranylgeranyl-pyrophoshate via Chl-GG, but rather directly from phytyl-pyrophosphate. Phylogenetic analysis of Chl synthase genes revealed that many species, including those of the Cucurbitaceae family, have two or more Chl synthase genes. This suggests that these additional genes, at least in some species, might encode isoforms involved in Pchl synthesis.

    Topics: Chlorophyll; Chlorophyll A; Cucurbitaceae; Phylogeny

2022
Distinct UV-A or UV-B irradiation induces protochlorophyllide photoreduction and bleaching in dark-grown pea (Pisum sativum L.) epicotyls.
    Photosynthesis research, 2019, Volume: 140, Issue:1

    The effects of distinct UV-A and UV-B radiations were studied on etiolated pea (Pisum sativum L.) epicotyls. Emission spectra of the native protochlorophyll and protochlorophyllide forms were measured when epicotyls were excited with 360 or 300 nm light. The UV-A (360 nm) excited mainly the non-enzyme-bound monomers of protochlorophyll and protochlorophyllide and the UV-B (300 nm) excited preferentially the flash-photoactive protochlorophyllide complexes. These latter complexes converted into short- and long-wavelength chlorophyllide forms at 10-s illumination with both wavelength irradiations. As the spectral changes were very small, the effects of longer illumination periods were studied. Room temperature fluorescence emission spectra were measured from the same epicotyl spots before and after irradiation with various wavelengths between 280 and 360 nm for 15 min and the "illuminated" minus "dark" difference spectra were calculated. Both the UV-A and the UV-B irradiations caused photoreduction of protochlorophyllide into chlorophyllide. At 10 µmol photons m

    Topics: Chlorophyll; Chlorophyllides; Darkness; Fluorescence; Microscopy, Fluorescence; Oxidation-Reduction; Photochemical Processes; Photosynthesis; Pisum sativum; Plant Leaves; Protochlorophyllide; Ultraviolet Rays

2019
Characterization of 3-Acetyl Chlorophyll a and 3-Acetyl Protochlorophyll a Accommodated in the B800 Binding Sites of Photosynthetic Light-Harvesting Complex 2 in the Purple Photosynthetic Bacterium Rhodoblastus acidophilus.
    Photochemistry and photobiology, 2018, Volume: 94, Issue:4

    We present the detailed characterization on the reconstitution of two cyclic tetrapyrrole pigments that have the same substituents but differ in the degree of hydrogenation in the macrocycles from bacteriochlorophyll (BChl) a (7,8,17,18-tetrahydroporphyrin) into the binding sites of B800 BChl a in light-harvesting complex 2 (LH2) of purple photosynthetic bacteria. Both 3-acetyl chlorophyll (Chl) a (17,18-dihydroporphyrin) and 3-acetyl protochlorophyll (PChl) a (porphyrin) were inserted into the B800-binding pockets in LH2, indicating that these pockets allow alteration of the degree of hydrogenation in the cyclic tetrapyrroles. Redshifts of the Q

    Topics: Bacteriochlorophylls; Beijerinckiaceae; Binding Sites; Chlorophyll; Hydrogenation; Light-Harvesting Protein Complexes; Molecular Structure; Photosynthesis

2018
Transformation of plastids in soil-shaded lowermost hypocotyl segments of bean (Phaseolus vulgaris) during a 60-day cultivation period.
    Physiologia plantarum, 2017, Volume: 159, Issue:4

    The maintenance but substantial transformation of plastids was found in lowermost hypocotyl segments of soil-grown bean plants (Phaseolus vulgaris cv. Magnum) during a 60-day cultivation period. Although the plants were grown under natural light-dark cycles, this hypocotyl segment was under full coverage of the soil in 5-7 cm depth, thus it was never exposed to light. The 4-day-old plants were fully etiolated: amyloplasts, occasionally prolamellar bodies, protochlorophyllide (Pchlide) and protochlorophyll (Pchl) were found in the hypocotyls of these young seedlings. The 633 and 654 nm bands in the 77 K fluorescence emission spectra indicated the presence of Pchlide and Pchl pigments. During aging, both the Pchlide and Pchl contents increased, however, the Pchl to Pchlide ratio gradually increased. In parallel, the contribution of the 654 nm form decreased and in the spectra of the 60-day-old samples, the main band shifted to 631 nm, and a new form appeared with an emission maximum at 641 nm. The photoactivity had been lost; bleaching took place at continuous illumination. The inner membranes of the plastids disappeared, the amount of starch storing amyloplasts decreased. These data may indicate the general importance of plastids for plant cell metabolism, which can be the reason for their maintenance. Also the general heterogeneity of plastid forms can be concluded: in tissues not exposed to light, Pchl accumulating plastids develop and are maintained even for a long period.

    Topics: Chlorophyll; Hypocotyl; Image Processing, Computer-Assisted; Phaseolus; Plastids; Protochlorophyllide; Soil; Spectrometry, Fluorescence; Transformation, Genetic

2017
Bisphenol A effects on the chlorophyll contents in soybean at different growth stages.
    Environmental pollution (Barking, Essex : 1987), 2017, Volume: 223

    Bisphenol A (BPA), a suspected endocrine disruptor, can modify normal plant growth and development. Photosynthesis provides material and energy for the growth and development of plants, in which chlorophyll (Chl) plays a significant role. Many studies have shown that the growth and metabolism of plants vary at different growth stages. Thus the sensitivity of plant's responses to environmental pollution is correspondingly different. We studied the effects of BPA on the Chl contents of soybean (Glycine Max L.) at different growth stages (seedling, flowering and podding, seed-filling and maturation) by measuring the contents of essential intermediates (5-aminolevulinic acid, porphobilinogen, protoporphyrin IX, magnesium protoporphyrin and protochlorophyll) and the activities of key enzymes (5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, magnesium chelatase) in chlorophyll synthesis. Low-dose (1.5 mg/L) BPA exposure increased the activities of key enzymes in addition to the contents of intermediates in Chl synthesis at different growth stages, resulting in increases in Chl contents and net photosynthetic rate. In contrast, medium and high-dose (17.2, 50.0 mg/L) BPA exposure produced inhibitory effects on the indices. Following the withdrawal of BPA exposure, the indices recovered to a degree that was related to the plant growth stage. The effect level (high to low) of BPA on these indices at different growth stages was: seedling stage > maturation stage > flowering and podding stage > seed-filling stage. The reverse effect was observed following the withdrawal of BPA exposure. The responses of key enzymes in plant Chl synthesis to BPA illustrate how BPA affects Chl contents. The effects of BPA show clear differences at different plant growth stages.

    Topics: Benzhydryl Compounds; Biosynthetic Pathways; Chlorophyll; Endocrine Disruptors; Environmental Pollutants; Flowers; Glycine max; Phenols; Protoporphyrins; Seedlings; Seeds

2017
Synthesis of chlorophyll-c derivatives by modifying natural chlorophyll-a.
    Photosynthesis research, 2016, Volume: 127, Issue:3

    Chlorophyll-a (Chl-a) was extracted from cyanobacterial cells and modified to methyl pyropheophorbide-a. The 3-vinyl-chlorin was transformed to zinc complex of the corresponding 3-acetyl-porphyrin. The zinc porphyrin was oxidized to give cis-7,8- and 17,18-dihydroxy-chlorins as well cis-7,8-cis-17,18-tetrahydroxybacteriochlorin. After zinc-demetallation, the isolated cis-7,8- and 17,18-diols were reduced at the 3-acetyl group and triply dehydrated under acidic conditions to afford two regioisomeric 3-vinyl-porphyrins, methyl divinyl-pyroprotopheophorbide-a possessing the 8-vinyl group and 17-propionate residue (one of the divinyl-protoChl-a derivatives) and methyl pyropheophorbide-c 1 possessing the 8-ethyl group and 17-acrylate residue (one of the Chl-c 1 derivatives), respectively. The resulting 7,8,17,18-tetrol was reduced and then acidically treated, giving five-fold dehydrated free base porphyrin, methyl pyropheophorbide-c 2 possessing the 3,8-divinyl groups and 17-acrylate residue (one of the Chl-c 2 derivatives). The visible absorption and fluorescence emission spectra of the three semi-synthetic 3-vinyl-porphyrins in dichloromethane were compared with those of the corresponding 8-ethyl-porphyrin bearing the 17-propionate residue, methyl pyroprotopheophorbide-a (one of the protoChl-a derivatives). The Soret and Qy absorption maxima were shifted to longer wavelengths with an increase of π-conjugation in a molecule: protoChl-a (8-CH2CH3/17-CH2CH2COOCH3) < divinyl-protoChl-a (8-CH=CH2/17-CH2CH2COOCH3) < Chl-c 1 (8-CH2CH3/17-CH=CHCOOCH3) < Chl-c 2 derivatives (8-CH=CH2/17-CH=CHCOOCH3). The 17(1),17(2)-dehydrogenation broadened the absorption bands. The emission maxima were bathochromically shifted in the same order. The reaction mechanism of the present dehydration indicates that the biosynthetic pathway of Chls-c would include the hydroxylation of the 17-propionate reside at the 17(1)-position and successive dehydration to the 17-acrylate residue.

    Topics: Acrylates; Biosynthetic Pathways; Chlorophyll; Chlorophyll A; Optical Phenomena; Spectrometry, Fluorescence

2016
Wavelength-dependent photooxidation and photoreduction of protochlorophyllide and protochlorophyll in the innermost leaves of cabbage (Brassica oleracea var. capitata L.).
    Photosynthesis research, 2016, Volume: 128, Issue:1

    The photoreduction and photooxidation processes of different protochlorophyll(ide) forms were studied in the innermost leaves of cabbage (Brassica oleracea var. capitata L.) under monochromatic irradiations. Room-temperature fluorescence emission spectra were measured from the same leaf spots before and after illumination to follow the wavelength dependence of the photochemical reactions. Short-wavelength light of 7 µmol photons m(-2) s(-1) (625-630 nm) provoked mainly bleaching, and longer wavelengths (630-640 nm) caused both bleaching and photoreduction, while above 640 nm resulted in basically photoreduction. When bleached leaves were kept in darkness at room temperature, all protochlorophyll(ide) forms regenerated during 72 h. Oxygen-reduced environment decreased the extent of bleaching suggesting the involvement of reactive oxygen species. These results confirm that the short-wavelength, 628 nm absorbing, and 633 nm emitting protochlorophyll(ide) form in etiolated cabbage leaves sensibilizes photooxidation. However, the 628 nm light at low intensities stimulates the photoreduction of the longer wavelength protochlorophyllide forms. Kinetic measurements showed that photoreduction saturates at a low PFD (photon flux density) compared to bleaching, suggesting that the quantum yield of photoreduction is higher than that of bleaching.

    Topics: Brassica; Chlorophyll; Fluorescence; Light; Oxidation-Reduction; Oxygen; Photochemical Processes; Plant Leaves; Protochlorophyllide; Sunlight

2016
Effects of bisphenol A on chlorophyll synthesis in soybean seedlings.
    Environmental science and pollution research international, 2015, Volume: 22, Issue:8

    Bisphenol A (BPA), as an emerging environmental pollutant, is potentially harmful to plant growth. Chlorophyll (Chl) is critical in photosynthesis that provides matter and energy for plant growth. How BPA affects the chlorophyll content remains largely unknown. Here, the effects of BPA on Chl synthesis in soybean seedlings were investigated. Exposure to 1.5 mg/L BPA decreased the 5-aminolevulinic acid (ALA) content and increased protoporphyrin IX (Proto IX), magnesium protoporphyrin, and protochlorophyll contents and 5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, uroporphyrinogen III decarboxylase, and protoporphyrinogen oxidase activities. Exposure to 17.2 and 50.0 mg/L BPA exerted the opposite effects on these four intermediates and five enzymes. Following the withdrawal of BPA exposure, the aforementioned parameters gradually recovered, except magnesium protoporphyrin content in exposure to 50.0 mg/L BPA. Our findings revealed that exposure to low-concentration BPA increased the Chl content in soybean seedlings through improving Chl synthesis, especially the conversion from ALA to Proto IX, whereas exposure to high-concentration BPA decreased the Chl content through inhibiting Chl synthesis, especially the conversion from ALA to Proto IX. The dual effects of BPA were largely reversed following the withdrawal of BPA exposure.

    Topics: Aminolevulinic Acid; Analysis of Variance; Benzhydryl Compounds; Biosynthetic Pathways; Chlorophyll; Environmental Pollutants; Glycine max; Hydroxymethylbilane Synthase; Phenols; Photosynthesis; Plant Leaves; Porphobilinogen Synthase; Protoporphyrinogen Oxidase; Protoporphyrins; Seedlings; Spectrometry, Fluorescence; Uroporphyrinogen Decarboxylase; Uroporphyrinogen III Synthetase

2015
Light piping activates chlorophyll biosynthesis in the under-soil hypocotyl section of bean seedlings.
    Journal of photochemistry and photobiology. B, Biology, 2014, Volume: 140

    Protochlorophyllide (Pchlide), protochlorophyll (Pchl) and chlorophyll (Chl) contents, their distribution and native arrangements were studied in under-soil hypocotyl segments of 4-, 7- and 14-day-old bean (Phaseolus vulgaris L. cv. Magnum) seedlings. The plants were grown in general potting soil under natural illumination conditions in pots. For sample collection, the pots were transferred into dark-room where all manipulations were done under dim green light. The pigments were extracted with acetone; phase separation was used to identify the Pchl contents. Fluorescence microscopic studies were done and 77K fluorescence emission spectra were recorded. Using a special setup of a spectrofluorometer, the vertical light piping properties of the above-soil shoots were measured. The segments in the 5-7 cm deep soil region contained Pchlide and Pchl in 4- and 7-day-old seedlings and the segments towards the soil surface contained Chl in increasing amounts. In parallel with the pith degradation of hypocotyls, the Chl content of elder seedlings increased in the deeper under-soil segments. These results prove that the tissue structure of the shoot ensures light piping thus greening process and chloroplast formation can take place even in under-soil organs not directly exposed to light.

    Topics: Chlorophyll; Hypocotyl; Light; Microscopy, Fluorescence; Phaseolus; Plant Proteins; Protochlorophyllide; Seedlings; Spectrometry, Fluorescence; Time Factors

2014
Etioplasts with protochlorophyll and protochlorophyllide forms in the under-soil epicotyl segments of pea (Pisum sativum) seedlings grown under natural light conditions.
    Physiologia plantarum, 2013, Volume: 148, Issue:2

    To study if etiolation symptoms exist in plants grown under natural illumination conditions, under-soil epicotyl segments of light-grown pea (Pisum sativum) plants were examined and compared to those of hydroponically dark-grown plants. Light-, fluorescence- and electron microscopy, 77 K fluorescence spectroscopy, pigment extraction and pigment content determination methods were used. Etioplasts with prolamellar bodies and/or prothylakoids, protochlorophyll (Pchl) and protochlorophyllide (Pchlide) forms (including the flash-photoactive 655 nm emitting form) were found in the (pro)chlorenchyma of epicotyl segments under 3 cm soil depth; their spectral properties were similar to those of hydroponically grown seedlings. However, differences were found in etioplast sizes and Pchlide:Pchl molar ratios, which indicate differences in the developmental rates of the under-soil and of hydroponically developed cells. Tissue regions closer to the soil surface showed gradual accumulation of chlorophyll, and in parallel, decrease of Pchl and Pchlide. These results proved that etioplasts and Pchlide exist in soil-covered parts of seedlings even if they have a 3-4-cm long photosynthetically active shoot above the soil surface. This underlines that etiolation symptoms do develop under natural growing conditions, so they are not merely artificial, laboratory phenomena. Consequently, dark-grown laboratory plants are good models to study the early stages of etioplast differentiation and the Pchlide-chlorophyllide phototransformation.

    Topics: Chlorophyll; Chloroplasts; Darkness; Hydroponics; Light; Microscopy, Electron; Pisum sativum; Plant Shoots; Protochlorophyllide; Seedlings; Soil; Spectrometry, Fluorescence

2013
Protochlorophyllide and protochlorophyll in model membranes - an influence of hydrophobic side chain moiety.
    Biochimica et biophysica acta, 2013, Volume: 1828, Issue:3

    In the present work, a comparative study of protochlorophyllide- and protochlorophyll-lipid interaction was performed on liposomes prepared from phospholipids and galactolipids, which had a pigment content varying from 0.1 to 4mol%. The incorporation of pigment molecules into the lipid bilayer and pigment-pigment interactions were investigated. Protochlorophyllide entered the lipid bilayer spontaneously and showed fluorescence spectra characteristic of its monomers. Similar spectra were observed for protochlorophyll where its concentration was low. However, the fluorescence maxima of protochlorophyll monomers were blue-shifted compared to those of protochlorophyllide by about 5nm. Protochlorophyll at high concentrations formed transient aggregates that showed an additional fluorescence band with a maximum at around 685nm, especially in liposomes prepared from phospholipids. For both compounds, the Stern-Volmer constant for KI quenching was much lower in liposomes than in solution, which confirmed the incorporation of these compounds into the lipid bilayer. Two populations of protochlorophyll that differed in their accessibility to quenching by KI were determined, and the proportions between them for different lipids are discussed. Protochlorophyllide showed such heterogeneity only in DPPC membranes. Quenching with 5- and 16-SASL revealed a localization of the porphyrin ring of both Pchl and Pchlide in the polar headgroup area of the lipid bilayer. The side chain of protochlorophyll forced these molecules to localize deeper in the bilayer in the case of DPPC in gel phase.

    Topics: Biophysics; Chlorophyll; Cucurbita; Glycolipids; Hydrophobic and Hydrophilic Interactions; Lipid Bilayers; Lipids; Liposomes; Models, Chemical; Phospholipids; Protochlorophyllide; Solvents; Spectrometry, Fluorescence; Spectrophotometry; Triticum

2013
Cerium relieves the inhibition of chlorophyll biosynthesis of maize caused by magnesium deficiency.
    Biological trace element research, 2011, Volume: 143, Issue:1

    Lanthanoids (Ln) were demonstrated to improve chlorophyll formation and the growth of plants. But the mechanism of the fact that Ln promotes chlorophyll biosynthesis of plants is poorly understood. The main aim of the study was to determine Ln effects in chlorophyll formation of maize under magnesium (Mg) deficiency. Maize plants were cultivated in Hoagland's solution. They were subjected to Mg deficiency and to cerium administered in Mg-deficient Hoagland's media, and then the contents of various chlorophyll precursors and gen expressions of the key enzymes of chlorophyll biosynthesis were examined. The decrease of chlorophyll contents in maize leaves caused by Mg deficiency suggested an inhibition of chlorophyll synthesis that was inhibited by a reduction of the precursors as measured by analyzing the contents of δ-aminolevulinic acid, porphobilinogen, uroporphyrinogen III, Mg-protoporphyrin IX, and protochlorophyll, as well as the expression levels of magnesium chelatase, magnesium-protoporphyrin IX methyltransferase, and chlorophyll synthase; Mg deficiency significantly inhibited the transformation from coproporphyrinogen III or protoporphyrin IX to chlorophyll. However, cerium addition significantly relieved the inhibition of chlorophyll biosynthesis in maize caused by Mg deficiency and increased chlorophyll content and promoted a series of transformations from δ-aminolevulinic acid to chlorophyll and maize growth under Mg deficiency. It implied that cerium might partly substitute for the role of Mg.

    Topics: Aminolevulinic Acid; Cerium; Chlorophyll; Coproporphyrinogens; Lyases; Magnesium; Zea mays

2011
Site-specific solvation of the photoexcited protochlorophyllide a in methanol: formation of the hydrogen-bonded intermediate state induced by hydrogen-bond strengthening.
    Biophysical journal, 2008, Jan-01, Volume: 94, Issue:1

    The site-specific solvation of the photoexcited protochlorophyllide a (Pchlide a) in methanol solvent was investigated using the time-dependent density functional theory method for the first time to our knowledge. The intermolecular site-specific coordination and hydrogen-bonding interactions between Pchlide a and methanol molecules play a very important role in the steady-state and time-resolved spectra. All the calculated absorption and fluorescence spectra of the isolated Pchlide a and its coordinated and hydrogen-bonded complexes with methanol demonstrate that the novel fluorescence shoulder at approximately 690 nm of Pchlide a in methanol should be ascribed to the coordinated and hydrogen-bonded Pchlide a-(MeOH)(4) complex. This coordinated and hydrogen-bonded complex can also account for the intermediate state found in the time-resolved spectroscopic studies. Herein, we have theoretically confirmed that the intermolecular coordination and hydrogen bonds between Pchlide a and methanol molecules can be strengthened in the electronically excited state of Pchlide a. Furthermore, the site-specific solvation of the photoexcited Pchlide a can be induced by the intermolecular coordination and hydrogen-bond strengthening upon photoexcitation. Then the hydrogen-bonded intermediate state is formed in 22-27 ps timescales after the site-specific solvation. All the steady-state and time-resolved spectral features of Pchlide a in different solvents can be explained by the formation of this hydrogen-bonded intermediate state after the site-specific solvation, which is induced by the coordination and hydrogen-bond strengthening.

    Topics: Binding Sites; Chlorophyll; Computer Simulation; Hydrogen; Hydrogen Bonding; Light; Methanol; Models, Chemical; Models, Molecular; Photochemistry; Solvents

2008
Cytochrome b6f is a dimeric protochlorophyll a binding complex in etioplasts.
    The FEBS journal, 2008, Volume: 275, Issue:5

    The cytochrome b6f complex is a dimeric protein complex that is of central importance for photosynthesis to carry out light driven electron and proton transfer in chloroplasts. One molecule of chlorophyll a was found to associate per cytochrome b6f monomer and the structural or functional importance of this is discussed. We show that etioplasts which are devoid of chlorophyll a already contain dimeric cytochrome b6f. However, the phytylated chlorophyll precursor protochlorophyll a, and not chlorophyll a, is associated with subunit b6. The data imply that a phytylated tetrapyrrol is an essential structural requirement for assembly of cytochrome b6f.

    Topics: Adenosine Triphosphatases; Chlorophyll; Chloroplasts; Cytochrome b6f Complex; Dimerization; Plant Proteins; Ribulose-Bisphosphate Carboxylase

2008
Solvent effects on fluorescence properties of protochlorophyll and its derivatives with various porphyrin side chains.
    European biophysics journal : EBJ, 2008, Volume: 37, Issue:7

    Fluorescence spectra and fluorescence lifetimes of protochlorophyll (Pchl) were measured in organic solvents having different physical and chemical properties and were analyzed taking into account the nonspecific (dependent on bulk solvent parameters), and specific (e.g. H bonds, Mg coordination) solvent-solute interactions. The energy of the fluorescence emission band decreased, while the Stokes shift increased for increasing solvent orientation polarizability, which is a function of both the dielectric constant (epsilon) and the refractive index (n). The extent of the dependence of the Stokes shift on solvent orientation polarizability was higher in protic (i.e. those able to form hydrogen-binding) than in aprotic solvents. High value of the Stokes shift was also observed in pyridine and methanol, i.e. in solvents hexacoordinating the central Mg atom. The fluorescence decay of Pchl was monoexponential in all of the investigated solvents. The fluorescence lifetime decreased for increasing solvent orientation polarizability from 5.5 +/- 0.1 ns in 1,4-dioxane to 3.3 +/- 0.1 ns in methanol. Longer lifetime values were observed in the case of aprotic solvents than in protic solvents. The hexacoordination of Mg had no effect on the fluorescence lifetime. The present data are discussed with respect to results found for protochlorophyllide (Pchlide) (Myśliwa-Kurdziel et al. in Photochem Photobiol 79:62-67, 2004), and they indicate that the presence of phytol chain in the porphyrin ring influences the spectral properties of the whole chromophore. This is the first complex analysis comparing the fluorescence emission and fluorescence lifetimes of purified Pchl and Pchlide.

    Topics: Chlorophyll; Diterpenes; Fluorescence; Organic Chemicals; Phytol; Porphyrins; Protochlorophyllide; Solvents; Temperature; Time Factors; Vinyl Compounds; Viscosity

2008
Protochlorophyll complexes with similar steady-state fluorescence characteristics can differ in fluorescence lifetimes. A model study in Triton X-100.
    Journal of photochemistry and photobiology. B, Biology, 2007, Mar-01, Volume: 86, Issue:3

    The steady-state and time-resolved fluorescence characteristics of protochlorophyll (Pchl) dissolved in neat Triton X-100 and in Triton X-100 micelles were investigated, and the fluorescence lifetimes of different Pchl spectral forms were studied. Varying the concentration of Pchl or diluting the micellar solutions either with a buffer or with a micellar solution, 631-634, 645-655, 680-692 and above 700 nm emitting Pchl complexes were prepared, the ratios of which varied from one another. The fluorescence decay of the 631-634 nm emitting (monomeric) form had a mono-exponential character with a 5.4-ns fluorescence lifetime. The long-wavelength Pchl complexes (aggregates) had two fluorescence lifetime values within a range of 1.4-3.9 ns and 0.15-0.84 ns, which showed high variability in different environments. Depending on the conditions, either mono- or double-exponential fluorescence decay was found for a fluorescence band at 680-685 nm. These data show that despite their very similar steady-state fluorescence properties, Pchl complexes can differ in fluorescence lifetimes, which may reflect different molecular structures, intrinsic geometries or different molecular interactions. This underlines the importance of complex spectroscopic analysis for a precise description of native and artificial chlorophyllous pigment forms.

    Topics: Buffers; Chlorophyll; Cucurbita; Hydrogen-Ion Concentration; Micelles; Octoxynol; Solubility; Spectrometry, Fluorescence

2007
Enzymology below 200 K: the kinetics and thermodynamics of the photochemistry catalyzed by protochlorophyllide oxidoreductase.
    Proceedings of the National Academy of Sciences of the United States of America, 2002, Aug-20, Volume: 99, Issue:17

    The chlorophyll biosynthesis enzyme protochlorophyllide reductase (POR) catalyzes the light-dependent reduction of protochlorophyllide (Pchlide) into chlorophyllide in the presence of NADPH. As POR is light-dependent, catalysis can be initiated by illumination of the enzyme-substrate complex at low temperatures, making it an attractive model for studying aspects of biological proton and hydride transfers. The early stages in the photoreduction, involving Pchlide binding and an initial photochemical reaction, have been studied in vitro by using low-temperature fluorescence and absorbance measurements. Formation of the ternary POR-NADPH-Pchlide complex produces red shifts in the fluorescence and absorbance maxima of Pchlide, allowing the dissociation constant for Pchlide binding to be measured. We demonstrate that the product of an initial photochemical reaction, which can occur below 200 K, is a nonfluorescent intermediate with a broad absorbance band at 696 nm (A696) that is suggested to represent an ion radical complex. The temperature dependence of the rate of A696 formation has allowed the activation energy for the photochemical step to be calculated and has shown that POR catalysis can proceed at much lower temperatures than previously thought. Calculations of differences in free energy between various reaction intermediates have been calculated; these, together with the quantum efficiency for Pchlide conversion, suggest a quantitative model for the thermodynamics of the light-driven step of Pchlide reduction.

    Topics: Binding Sites; Catalysis; Chlorophyll; Cyanobacteria; Enzymes; Kinetics; Oxidoreductases; Oxidoreductases Acting on CH-CH Group Donors; Photochemistry; Recombinant Proteins; Spectrophotometry; Thermodynamics

2002
Biosynthesis of chlorophyll from protochlorophyll(ide) in green plant leaves.
    Biochemistry. Biokhimiia, 2002, Volume: 67, Issue:8

    Using spectral methods, the biosynthesis of protochlorophyll(ide) and chlorophyll(ide) in green plant leaves was studied. The main chlorophyll precursors in the green leaves (as in etiolated leaves) were photoactive photocholorophyll(ide) forms Pchl(ide)655/650(448) and Pchl(ide)653/648(440). The contributions into Chl biosynthesis of the shorter-wavelength precursor forms, which were accumulated in darkened green leaves as well, were completely absent (of Pchl(ide) 633/628(440)) or insignificant (of Pchl(ide) 642/635(444)).

    Topics: Chlorophyll; Hibiscus; Hordeum; Phaseolus; Pisum sativum; Plant Leaves; Protochlorophyllide; Spectrometry, Fluorescence; Temperature; Time Factors; Zea mays

2002
Biliverdin reductase-induced phytochrome chromophore deficiency in transgenic tobacco.
    Plant physiology, 2001, Volume: 125, Issue:1

    Targeted expression of mammalian biliverdin IXalpha reductase (BVR), an enzyme that metabolically inactivates linear tetrapyrrole precursors of the phytochrome chromophore, was used to examine the physiological functions of phytochromes in the qualitative short-day tobacco (Nicotiana tabacum cv Maryland Mammoth) plant. Comparative phenotypic and photobiological analyses of plastid- and cytosol-targeted BVR lines showed that multiple phytochrome-regulated processes, such as hypocotyl and internode elongation, anthocyanin synthesis, and photoperiodic regulation of flowering, were altered in all lines examined. The phytochrome-mediated processes of carotenoid and chlorophyll accumulation were strongly impaired in plastid-targeted lines, but were relatively unaffected in cytosol-targeted lines. Under certain growth conditions, plastid-targeted BVR expression was found to nearly abolish the qualitative inhibition of flowering by long-day photoperiods. The distinct phenotypes of the plastid-targeted BVR lines implicate a regulatory role for bilins in plastid development or, alternatively, reflect the consequence of altered tetrapyrrole metabolism in plastids due to bilin depletion.

    Topics: Agrobacterium tumefaciens; Anthocyanins; Chlorophyll; Hypocotyl; Light; Nicotiana; Oxidoreductases Acting on CH-CH Group Donors; Phytochrome; Plants, Genetically Modified; Recombinant Proteins

2001
Light- and cold-stress effects on the greening process in epicotyls and young stems of red oak (Quercus rubra) seedlings.
    Tree physiology, 2001, Volume: 21, Issue:8

    Protochlorophyllide (Pchlide) and protochlorophyll (Pchl) were found in epicotyls of 14-day-old dark-germinated seedlings and in 100-day-old dark-grown stems of red oak (Quercus rubra L.). Fluorescence spectroscopy measurements of epicotyls at 77 K showed that the majority of Pchlide and Pchl is present as a shorter wavelength-emitting monomer with a fluorescence emission maximum at 629-631 nm. A small amount of a monomeric form emitting at 635-636 nm was also present. Minor amounts of Pchlide were aggregated into larger complexes with fluorescence emission maxima at 640, 644-646 and 652-654 nm, as seen in etiolated leaves. Flash illumination transformed the 652-654-nm-emitting form to chlorophyllide, but not those forms with emission maxima at 629-631, 635-636 and 644-646 nm. These shorter wavelength-emitting forms were transformed to chlorophyllide by continuous illumination, but the process took several hours. Epicotyls and young stems were light sensitive, with exposure to full daylight causing strong pigment bleaching and tissue destruction. Complete greening took place only at low irradiances. Light sensitivity was greater at 4 degrees C than at room temperature. We conclude that the monomeric arrangement of the pigments accounted for the light and temperature sensitivity of the greening process in epicotyls and stems.

    Topics: Chlorophyll; Cold Temperature; Light; Plant Stems; Protochlorophyllide; Quercus; Spectrometry, Fluorescence; Trees

2001
Normal-phase HPLC separation of possible biosynthetic intermediates of pheophytin a and chlorophyll a'.
    Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, 2001, Volume: 17, Issue:4

    Normal-phase HPLC conditions have been developed for separating the C17(3) isoprenoid isomers, which are expected to be formed as biosynthetic intermediates of chlorophyll (Chl) a, Chl a' (C13(2)-epimer of Chl a), pheophytin (Pheo) a and protochlorophyll (PChl). The application of these conditions to pigment composition analysis of greening etiolated barley leaves allowed us to detect, for the first time, the C17(3) isomers of Chl a', a possible constituent of the primary electron donor of photosystem (PS) I, P700, and those of Pheo a, the primary electron acceptor of PS II, in the very early stage of greening. The C17(3) isomer distribution patterns were approximately the same between Chl a and Chl a', but significantly different between Pheo a and Chl a', probably reflecting the similarity and difference, respectively, in the biosynthetic pathways of these pigment pairs.

    Topics: Carbohydrate Sequence; Chlorophyll; Chlorophyll A; Chromatography, High Pressure Liquid; Hordeum; Isomerism; Pheophytins; Plant Leaves; Plant Proteins

2001
Modification of distinct aspects of photomorphogenesis via targeted expression of mammalian biliverdin reductase in transgenic Arabidopsis plants.
    Plant physiology, 1999, Volume: 121, Issue:2

    The phenotypic consequences of targeted expression of mammalian biliverdin IXalpha reductase (BVR), an enzyme that metabolically inactivates the linear tetrapyrrole precursors of the phytochrome chromophore, are addressed in this investigation. Through comparative phenotypic analyses of multiple plastid-targeted and cytosolic BVR transgenic Arabidopsis plant lines, we show that the subcellular localization of BVR affects distinct subsets of light-mediated and light-independent processes in plant growth and development. Regardless of its cellular localization, BVR suppresses the phytochrome-modulated responses of hypocotyl growth inhibition, sucrose-stimulated anthocyanin accumulation, and inhibition of floral initiation. By contrast, reduced protochlorophyll levels in dark-grown seedlings and fluence-rate-dependent reduction of chlorophyll occur only in transgenic plants in which BVR is targeted to plastids. Together with companion analyses of the phytochrome chromophore-deficient hy1 mutant, our results suggest a regulatory role for linear tetrapyrroles within the plastid compartment distinct from their assembly with apophytochromes in the cytosol.

    Topics: Agrobacterium tumefaciens; Animals; Anthocyanins; Arabidopsis; Chlorophyll; Genetic Vectors; Hypocotyl; Kidney; Kinetics; Light; Mammals; Morphogenesis; Oxidoreductases; Oxidoreductases Acting on CH-CH Group Donors; Plants, Genetically Modified; Rats; Recombinant Proteins

1999
Chlorophyll a biosynthetic heterogeneity.
    Ciba Foundation symposium, 1994, Volume: 180

    Chlorophyll a biosynthesis is presently interpreted in terms of two different biochemical pathways. According to one pathway, chlorophyll a is made via a single linear chain of reactions starting with divinylprotoporphyrin IX and ending with monovinylchlorophyll a. The experimental evidence for this pathway is marred by incompletely characterized intermediates that were detected in Chlorella mutants. The second pathway considers chlorophyll a to be made via multiple and parallel biosynthetic routes that result in the formation and accumulation of monovinyl- and divinylchlorophyll a chemical species. Two of these routes, namely the di/monocarboxylic monovinyl and divinyl routes, are responsible for the biosynthesis of most of the chlorophyll a in green plants. The experimental evidence for these two routes consists of: (a) the detection and spectroscopic characterization of intermediates and end products; (b) the demonstration of precursor-product relationships between various intermediates in vivo and in vitro; and (c) the detection of 4-vinylreductases that appear to be mainly responsible for the observed biosynthetic heterogeneity. The biological significance of chlorophyll a biosynthetic heterogeneity is becoming better understood. On the basis of the prevalence of the di/monocarboxylic monovinyl-and divinylchlorophyll a biosynthetic routes, green plants have been classified into three different greening groups. It now appears that the major chlorophylls in the euphotic zone of tropical waters are divinylchlorophyll a and b. It also appears that the di/monocarboxylic monovinyl and divinyl biosynthetic routes lead to the formation of different pigment proteins in different greening groups of plants, and that the more highly evolved monovinylchlorophyll a biosynthetic route is associated with higher field productivity in wheat.

    Topics: Chlorella; Chlorophyll; Models, Chemical; Mutagenesis; Pyrroles; Tetrapyrroles

1994
Development of plastid membranes in immobilized systems.
    Advances in experimental medicine and biology, 1988, Volume: 238

    Topics: Agar; Cell Fractionation; Chlorophyll; Chloroplasts; Enzymes, Immobilized; Intracellular Membranes; Microspheres; Morphogenesis; Oxidoreductases; Oxidoreductases Acting on CH-CH Group Donors; Spectrometry, Fluorescence

1988
Polyethylene-based high-performance liquid chromatography of chloroplast pigments: resolution of mono- and divinyl chlorophyllides and other pigment mixtures.
    Analytical biochemistry, 1987, May-01, Volume: 162, Issue:2

    In addition to most chlorophylls and their derivatives, monovinyl and divinyl chlorophyll species were separated by high-performance liquid chromatography, using a polyethylene column and a simple elution with aqueous acetone. Peak retention and resolution of the pigment separation were greatly increased by increasing the polarity of the mobile phase and also by decreasing the column temperature. Polyethylene chromatography showed chlorophyll separation behavior similar to that of the octadecyl silica column, but it showed no adsorption of the pigment species containing free carboxylic acid groups, enabling the complete separation of chlorophylls and their derivatives. Polyethylene is a superior alternative stationary phase to the known reversed-phase materials for chlorophyll separation and analysis.

    Topics: Acetone; Bacteriochlorophylls; Chlorophyll; Chlorophyllides; Chloroplasts; Chromatography, High Pressure Liquid; Polyethylenes

1987
[Primary processes in photosynthesis and chlorophyll biosynthesis].
    Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme, 1985, Issue:28

    Topics: Chlorophyll; Photosynthesis; Rhodobacter sphaeroides; Time Factors

1985
[Isolation and identification of protochlorophylls obtained by oxidation of corresponding chlorophylls].
    Biokhimiia (Moscow, Russia), 1977, Volume: 42, Issue:12

    Protochlorophyll with a high yield is isolated under oxidation of chlorophyll a by tetrachloro-o-quinone. A pigment, designated as protochlorophyll b, is isolated by the same way from chlorophyll b. A method of purification of the pigments obtained is worked out, their properties are studied and their structures are identified. The proposed method can be recommended for isolation of protochlorophyll a and b.

    Topics: Chemical Phenomena; Chemistry; Chlorophyll; Methods; Oxidation-Reduction; Spectrophotometry

1977
AN IMPROVED METHOD FOR THE ISOLATION OF CARBOXYDISMUTASE. PROBABLE IDENTITY WITH FRACTION I PROTEIN AND THE PROTEIN MOIETY OF PROTOCHLOROPHYLL HOLOCHROME.
    Biochemistry, 1965, Volume: 4

    Topics: Carboxy-Lyases; Chemical Phenomena; Chemistry; Chlorides; Chlorophyll; Chloroplasts; Chromatography; Enzyme Inhibitors; Isomerases; Kinetics; Phosphotransferases; Plants, Edible; Research; Ribulose-Bisphosphate Carboxylase; Spectrophotometry; Sulfates; Ultracentrifugation

1965
MAGNESIUM 2,4-DIVINYLPHAEOPORPHYRIN A5 MONOMETHYL ESTER, A PROTOCHLOROPHYLL-LIKE PIGMENT PRODUCED BY RHODOPSEUDOMONAS SPHEROIDES.
    The Biochemical journal, 1963, Volume: 89

    Topics: Chlorophyll; Chromatography; Esters; Magnesium; Porphyrins; Research; Rhodobacter sphaeroides; Rhodopseudomonas; Spectrophotometry

1963
Studies on a protochlorophyll-protein complex. I. Purification and molecular-weight determination.
    Biochimica et biophysica acta, 1962, Jul-30, Volume: 62

    Topics: Chlorophyll; Molecular Weight; Proteins

1962
Studies on a protochlorophyll-protein complex. II. The photo-conversion of protochlorophyll to chlorophyll alpha in the isolated complex.
    Biochimica et biophysica acta, 1962, Oct-22, Volume: 64

    Topics: Chlorophyll; Proteins

1962
Fine structure and pigment conversion in isolated etiolated proplastids.
    The Journal of biophysical and biochemical cytology, 1961, Volume: 11

    Proplastids containing a prolamellar body were isolated from leaves of etiolated bean plants. The isolation methods do not necessarily lead to destruction of their submicroscopic structure and most of the isolated proplastids show well preserved outer membranes, lamellar strands, and the prolamellar body. Morphological intactness of the proplastids varies; certain leaf fractions contain single prolamellar bodies as well as proplastids. Since pellets after centrifugation between 350 g and 1000 to 3000 g contain intact proplastids and, as was shown by quantitative experiments, the same fractions show photoconversion of protochlorophyll to chlorophyll, it is supposed that the isolated particles probably retain many of the properties which are characteristic of them in situ. Isolated proplastids may thus be a valuable tool in investigations on the development of the photosynthetic apparatus.

    Topics: Chlorophyll; Fabaceae; Photosynthesis; Pigments, Biological; Plant Leaves; Plants; Plastids

1961
The effect of low temperature on the development of the lamellar system in chloroplasts.
    The Journal of biophysical and biochemical cytology, 1960, Volume: 8

    The influence of low temperature (3 degrees C.) on development of submicroscopic structure in plastids of Zea m. leaves was studied. Leaves from 8-day old etiolated plants, with plastids showing the prolamellar body and few lamellae, were floated for 1 day on tap water both in the dark and in the light, at 26 degrees C and at 3 degrees C. The structures remain unchanged in the dark, independent of temperature. Whereas in the light at 26 degrees C., normal development of parallel compound lamellae and formation of grana occurs, in light at 3 degrees C. ring structures are formed. Under the latter conditions protochlorophyll is converted to chlorophyll, although the in situ absorption maximum is different from the one for chlorophyll in plants grown in light at 26 degrees C. When leaves were transferred from light at 3 degrees C. to light at 26 degrees C., ring structures in the plastids disappeared and normal development occurred. The possibility is discussed that development of parallel-arranged compound lamellae is due both to photochemical and synthetic processes, involving not only accumulation of chlorophyll, but also synthesis of other compounds.

    Topics: Chlorophyll; Chloroplasts; Cold Temperature; Light; Photosynthesis; Plant Leaves; Plants; Plastids; Temperature; Thylakoids

1960
[Dark and photochemical restoration of protochlorophyll].
    Biofizika, 1959, Volume: 4, Issue:3

    Topics: Chlorophyll

1959
Presence in root tips of a thermolabile factor causing the conversion of protochlorophyll to a leuco-compound.
    Nature, 1958, Oct-11, Volume: 182, Issue:4641

    Topics: Chlorophyll; Meristem

1958
The relationship between chlorophyll and the carotenoids in the algal flagellate, Euglena.
    The Journal of general physiology, 1956, May-20, Volume: 39, Issue:5

    1. We have obtained an action spectrum for chlorophyll formation in Euglena gracilis. This action spectrum is similar to the absorption spectrum of protochlorophyll. However, efforts to isolate and identify this pigment have been unsuccessful. 2. Porphyrins have been extracted from both the normal and dark-adapted Euglena and a chlorophyll-free mutant. 3. The "action" spectra for chlorophyll and carotenoid synthesis have been found to almost coincide, indicating that the same porphyrin-like molecule may influence the synthesis of both pigments. 4. It is indicated that two porphyrin-like systems are in operation simultaneously, one concerned with carotenoid "removal" and another involved in carotenoid and chlorophyll synthesis.

    Topics: Carotenoids; Chlorophyll; Euglena; Eukaryota; Pigments, Biological

1956
[Transformation of protochlorophyll into chlorophyll in etiolated maize leaves in infiltration of Picea excelsa extract].
    Doklady Akademii nauk SSSR, 1953, Feb-01, Volume: 88, Issue:4

    Topics: Biochemical Phenomena; Chlorophyll; Picea; Pinus; Plant Leaves; Zea mays

1953
[Active and non-active forms of protochlorophyll, chlorophyll, and bacteriochlorophyll in photosynthesizing organisms].
    Doklady Akademii nauk SSSR, 1953, Oct-21, Volume: 92, Issue:6

    Topics: Bacteriochlorophylls; Chlorophyll; Photosynthesis

1953
The action spectrum for the transformation of protochlorophyll to chlorophyll a in normal and albino corn seedlings.
    Archives of biochemistry and biophysics, 1951, Volume: 31, Issue:1

    Topics: Chlorophyll; Chlorophyll A; Light; Seedlings; Zea mays

1951
Protochlorophyll, precursor of chlorophyll.
    Archives of biochemistry, 1948, Volume: 19, Issue:3

    Topics: Chlorophyll

1948
The isolation and spectral absorption properties of protochlorophyll from etiolated barley seedlings.
    Journal of the American Chemical Society, 1948, Volume: 70, Issue:11

    Topics: Chlorophyll; Hordeum; Seedlings

1948