3-phosphonopyruvate and 2-amino-3-phosphonopropionic-acid

Phosphonic acid natural products have potent inhibitory activities that have led to their application as antibiotics. Recent studies uncovered large collections of gene clusters encoding for unknown phosphonic acids across microbial genomes. However, our limited understanding of their metabolism presents a significant challenge toward accurately informing the discovery of new bioactive compounds directly from sequence information alone. Here, we use genome mining to identify a family of gene clusters encoding a conserved branch point unknown to bacterial phosphonic acid biosynthesis. The products of this gene cluster family are the phosphonoalamides, four new phosphonopeptides with l-phosphonoalanine as the common headgroup. Phosphonoalanine and phosphonoalamide A are antibacterials, with strongest inhibition observed against strains of

Topics: Alanine; Anti-Bacterial Agents; Bacteria; Genome, Bacterial; Genomics; Microbial Sensitivity Tests; Multigene Family; Organophosphonates; Peptides; Pyruvates

The phosphonopyruvate hydrolase (PalA) found in Variovorax sp., Pal2, is a novel carbon-phosphorus bond cleavage enzyme, which is expressed even in the presence of high levels of phosphate, thus permitting phosphonopyruvate to be used as the sole carbon and energy source. Analysis of the regions adjacent to the palA gene revealed the presence of the five structural genes that constitute the 2-amino-3-phosphonopropionic acid (phosphonoalanine)-degradative operon. Reverse transcriptase-PCR (RT-PCR) experiments demonstrated that all five genes in the operon are transcribed as a single mRNA and that their transcription is induced by phosphonoalanine or phosphonopyruvate. Transcriptional fusions of the regulatory region of the phosphonoalanine degradative operon with the gfp gene were constructed. Expression analysis indicated that the presence of a LysR-type regulator (encoded by the palR gene) is essential for the transcription of the structural genes of the operon. Similar gene clusters were found in the sequenced genomes of six bacterial species from the Alpha-, Beta- and Gammaproteobacteria, and analysis of metagenomic libraries revealed that sequences related to palA are widely spread in the marine environment.

Topics: Alanine; Artificial Gene Fusion; Comamonadaceae; DNA, Bacterial; Gene Expression; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Gene Order; Genes, Reporter; Green Fluorescent Proteins; Molecular Sequence Data; Multigene Family; Pyruvates; Reverse Transcriptase Polymerase Chain Reaction; RNA, Bacterial; RNA, Messenger; Sequence Analysis, DNA; Sequence Homology

Incubation of 2-amino-3-phosphono[3-14C]propionic acid with cell-free preparations of Tetrahymena pyriformis resulted in incorporation of the radioactivity into phosphoenolpyruvate. No radioactivity was incorporated into phosphoenolpyruvate and 2-phosphonoacetate. Thus, the catabolic pathway of 2-amino-3-phosphonopropionic acid in Tetrahymena appears to be the same route as that found in rats through deamination to produce 3-phosphonopyruvate which is converted to 2-phosphonoacetaldehyde by decarboxylation, followed by both dephosphonylation and amination of the aldehyde to give acetaldehyde and 2-aminoethylphosphonic acid, respectively.

Topics: Acetaldehyde; Alanine; Aminoethylphosphonic Acid; Animals; Cell-Free System; Organophosphorus Compounds; Pyruvates; Tetrahymena pyriformis