Study on AsRiPPs, arsenic-containing ribosomally synthesized and post-translationally modified peptides
Disciplines
Biology
Abstract (300 words maximum)
Arsenic (As), the "king of poisons," has been a potential agent in medicine, particularly in antibiotic production. Notably, some bacteria utilize As to produce unique antibiotics, as represented by Arsinothricin (AST), the first known As-containing antibiotic. AST effectively controls various pathogens while sparing human cells, demonstrating the potential of As-containing antibiotics as a new pipeline for our shrinking antibiotic arsenal. To discover further novel As-containing antibiotics, we mined bacterial genome database using the AST Biosynthetic Gene Cluster (BGC) and found prospective BGCs for novel As-containing antibiotics in two Actinomyces: Microbispora rosea and Amycolatopsis tolypomycina. Gene analyses suggest that the BGCs code for As-containing RiPPs (Ribosomally Synthesized and Post-translationally modified Peptides), which we named AsRiPPs, where one gene encodes a precursor peptide with the remaining genes involved in post-translational modifications. From the M. rosea AsRiPP BGC, we selected four genes (one precursor peptide gene and three modifier genes), which we hypothesize are the minimum required gene set to produce an As-containing precursor of the encoded AsRiPP. The precursor peptide gene was solely expressed or co-expressed with the modifier genes in Escherichia coli in the presence of As and the AsRiPP production was analyzed. So far, we confirmed that the precursor peptide gene was expressed when solely expressed in E. coli and successfully purified the peptide by affinity chromatography. We are currently examining the strain that co-expresses the precursor peptide gene and modifier genes. As an alternate approach, we cultured A. tolypomycina with As and examined the production of the AsRIPP. As a result, we found that the strain produced an organic As species with antibiotic activity, suggesting that the strain produces an As-containing antibiotic, presumably an AsRiPP. These results demonstrate that further As-containing antibiotics exist in nature, offering a new avenue for the discovery of antibiotics.
Academic department under which the project should be listed
CSM - Molecular and Cellular Biology
Primary Investigator (PI) Name
Masafumi Yoshinaga
Study on AsRiPPs, arsenic-containing ribosomally synthesized and post-translationally modified peptides
Arsenic (As), the "king of poisons," has been a potential agent in medicine, particularly in antibiotic production. Notably, some bacteria utilize As to produce unique antibiotics, as represented by Arsinothricin (AST), the first known As-containing antibiotic. AST effectively controls various pathogens while sparing human cells, demonstrating the potential of As-containing antibiotics as a new pipeline for our shrinking antibiotic arsenal. To discover further novel As-containing antibiotics, we mined bacterial genome database using the AST Biosynthetic Gene Cluster (BGC) and found prospective BGCs for novel As-containing antibiotics in two Actinomyces: Microbispora rosea and Amycolatopsis tolypomycina. Gene analyses suggest that the BGCs code for As-containing RiPPs (Ribosomally Synthesized and Post-translationally modified Peptides), which we named AsRiPPs, where one gene encodes a precursor peptide with the remaining genes involved in post-translational modifications. From the M. rosea AsRiPP BGC, we selected four genes (one precursor peptide gene and three modifier genes), which we hypothesize are the minimum required gene set to produce an As-containing precursor of the encoded AsRiPP. The precursor peptide gene was solely expressed or co-expressed with the modifier genes in Escherichia coli in the presence of As and the AsRiPP production was analyzed. So far, we confirmed that the precursor peptide gene was expressed when solely expressed in E. coli and successfully purified the peptide by affinity chromatography. We are currently examining the strain that co-expresses the precursor peptide gene and modifier genes. As an alternate approach, we cultured A. tolypomycina with As and examined the production of the AsRIPP. As a result, we found that the strain produced an organic As species with antibiotic activity, suggesting that the strain produces an As-containing antibiotic, presumably an AsRiPP. These results demonstrate that further As-containing antibiotics exist in nature, offering a new avenue for the discovery of antibiotics.