ants and Hemolysis

Topics: Amines; Amino Acids; Animals; Ant Venoms; Anti-Bacterial Agents; Ants; Escherichia coli; Hemolysis; Histamine; Insect Proteins; Peptides; Saccharomyces cerevisiae; Spectrometry, Mass, Electrospray Ionization; Staphylococcus aureus; Tandem Mass Spectrometry

Antimicrobial peptides (AMPs) from cuticular extracts of worker ants of Trichomyrmex criniceps (Mayr, Hymenoptera: Formicidae) were isolated and evaluated for their antimicrobial activity. Eight peptides ranging in mass from 804.42 to 1541.04 Da were characterized using a combination of analytical and bioinformatics approach. All the eight peptides were novel with no similarity to any of the AMPs archived in the Antimicrobial Peptide Database. Two of the eight novel peptides, the smallest and the largest by mass were named Crinicepsin-1 and Crinicepsin-2 and were chemically synthesized by solid phase peptide synthesis. The two synthetic peptides had antibacterial and weak hemolytic activity.

Topics: Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Ants; Gram-Negative Bacteria; Gram-Positive Bacteria; Hemolysis; Humans; Insect Proteins; Oligopeptides; Tissue Extracts

Hymenoptera venoms constitute an interesting source of natural toxins that may lead to the development of novel therapeutic agents. The present study investigated the enzymatic and biological characteristics of the crude venom of the ant Odontomachus bauri. Its crude venom presents several protein bands, with higher staining for six proteins with gelatinolytic activity (17, 20, 26, 29, 43 and 48 kDa). The crude venom showed high proteolytic activity on azocasein at optimal pH 8.0 and 37 °C. In the presence of protease inhibitors as aprotinin, leupeptin and EDTA, the azocaseinolytic activity was reduced by 45%, 29% and 9%, respectively, suggesting that the enzymes present in the crude venom belong to the three classes of proteases, with the serine proteases in greater intensity. The crude venom degraded the fibrinogen α-chain faster than the β-chain, while the fibrinogen γ-chain remained unchanged. In biological assays, O. bauri venom showed hemolytic and coagulant activity in vitro, and defibrinating activity in vivo. In addition, the venom showed antimicrobial activity against Staphylococcus aureus and Escherichia coli as well as antiparasitic activity on Toxoplasma gondii infection in vitro. In that sense, this study sheds perspectives for pharmacological applications of O. bauri venom enzymes.

Topics: Animals; Ant Venoms; Anti-Bacterial Agents; Antiparasitic Agents; Ants; Cell Survival; Coagulants; Erythrocytes; Escherichia coli; HeLa Cells; Hemolysis; Humans; Insect Proteins; Macrophages; Male; Mice; Peptide Hydrolases; Staphylococcus aureus; Toxoplasma

Invasive species can impose novel selection pressures on natives, such as toxins to which native taxa are not adapted. Native species may survive such invasions by evolving mechanisms to avoid toxin exposure or increase toxin tolerance. Red imported fire ants (Solenopsis invicta) employ an alkaloid-based venom to defend their colonies and capture prey. In this study we aim to characterize the sublethal effects of invasive fire ant venom on a native vertebrate, the eastern fence lizard (Sceloporus undulatus), and to determine whether lizard populations that have been exposed to these fire ants for approximately 35 generations have increased physiological resistance to the venom. We documented the sublethal impact of fire ant venom on fence lizard performance by naturally exposing lizards to fire ant stings and recording changes in three fitness-relevant measures: bite force, righting ability, and sprint speed. We also measured blood hemolysis induced by the venom. To test for the development of physiological resistance to fire ant venom we compared whole-body performance and hemolysis for two populations of lizards with different fire ant invasion histories. Fire ant venom showed no dosage-dependent sublethal effects on performance. In addition, there is no evidence that lizards have evolved increased physiological resistance: the impact of fire ant venom on whole-body performance and hemolysis did not differ between the naïve and experienced populations. Lizards may instead rely on adaptive shifts in escape behavior and morphology following invasion to survive fire ant attack.

Topics: Alabama; Animals; Ant Venoms; Ants; Arkansas; Bite Force; Dose-Response Relationship, Drug; Ecosystem; Female; Hemolysis; Insect Bites and Stings; Lizards; Locomotion; Male

The synthetic peptide pilosulin 1, corresponding to the largest defined allergenic polypeptide found in the venom of the jumper ant Myrmecia pilosula, inhibited the incorporation of [methyl-3H]thymidine into proliferating Epstein-Barr transformed (EBV) B-cells. The LD50 was four-fold lower in concentration than melittin, a cytotoxic peptide found in honey bee venom. Loss of cell viability was assessed by flow cytometry by measuring the proportion of cells that fluoresced in the presence of the fluorescent dye 7-aminoactinomycin D. Examination of proliferating EBV B-cells indicated that the cells lost viability within a few minutes exposure to pilosulin 1. Partial peptides of pilosulin 1 were less efficient in causing loss of cell viability and the results suggest that the 22 N-terminal residues are critical to the cytotoxic activity of pilosulin 1. Normal blood white cells were also labile to pilosulin 1. T- and B-lymphocytes, monocytes and natural killer cells, however, were more labile than granulocytes. Analysis of pilosulin 1 using circular dichroism indicated that, in common with melittin and other Hymenoptera venom toxins, it had the potential to adopt an alpha-helical secondary structure.

Topics: Allergens; Amino Acid Sequence; Animals; Ant Venoms; Ants; B-Lymphocytes; Cell Division; Cell Survival; Cells, Cultured; Circular Dichroism; Hemolysis; Humans; In Vitro Techniques; Leukocytes; Leukocytes, Mononuclear; Molecular Sequence Data; Protein Structure, Secondary

The purpose of this study was to examine some of the pharmacological actions of venom from the Australian bulldog ant Myrmecia pyriformis. M. pyriformis venom was prepared by extraction of venom sacs in distilled water and centrifugation to remove insoluble material. Venom (2 micrograms/ml) produced a biphasic response of isolated guinea-pig ileum, i.e., an initial rapid contraction followed by a slower prolonged contraction. The histamine antagonist mepyramine (0.1 microM) inhibited the first phase of this response by approximately 80%. In the isolated rat stomach fundus strip (histamine-insensitive), venom (2-4 micrograms/ml) produced only a single contraction. Responses to venom of egg-albumin-sensitized guinea-pig ileum, were not significantly different before and after an anaphylactic response induced in vitro by egg albumin (0.5 mg/ml). Fluorometric assay showed that histamine accounted for 3.5 +/- 0.5% of the dry weight of M. pyriformis venom. Both the lipoxygenase/cyclooxygenase inhibitor BW755C and the cyclooxygenase inhibitor indomethacin significantly inhibited the response to venom of guinea-pig ileum (second phase) and rat fundus strip. M. pyriformis venom caused hemolysis of guinea pig blood. The degree of hemolysis was reduced significantly when boiled venom was used. No evidence was found that the venom contains acetylcholine, bradykinin, or 5-hydroxytryptamine or that the venom releases histamine from guinea-pig ileum. However, the results indicate that the venom contains histamine-like activity. In addition the venom was found to cause the release of cyclooxygenase products and to contain a heat-sensitive hemolytic factor.

Topics: Acetylcholine; Anaphylaxis; Anesthesia; Animals; Ant Venoms; Ants; Bradykinin; Eicosanoids; Guinea Pigs; Hemolysis; Histamine; In Vitro Techniques; Male; Muscle Contraction; Muscle, Smooth; Rats; Rats, Wistar; Serotonin; Species Specificity; Spectrometry, Fluorescence

Topics: Ant Venoms; Ants; Complement Activation; Complement C1; Complement C2; Complement C4; Complement Pathway, Classical; Electrophoresis, Paper; Hemolysis; Humans; Molecular Weight; Oligosaccharides; Time Factors

Topics: Animals; Ants; Chromatography, Gel; Electrophoresis, Starch Gel; Erythrocytes; Guinea Pigs; Hemolysis; Histamine Release; In Vitro Techniques; Muscle, Smooth; Proteins; Rabbits; Venoms

A crystalline hemolytic principle, shown to be a constituent of fire ant venom and having the properties of an amine, was isolated from crude extracts of whole ants. The chromatographic procedure of isolation is described, and a preliminary report is given about some properties of the substance.

Topics: Amines; Animals; Ant Venoms; Ants; Cell Death; Hemolysis; Venoms