Biosynthesis of isonitrile lipopeptides by conserved nonribosomal peptide synthetase gene clusters in Actinobacteria

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 114; no. 27; pp. 7025 - 7030
• Main Authors: Harris, Nicholas C., Sato, Michio, Herman, Nicolaus A., Twigg, Frederick, Cai, Wenlong, Liu, Joyce, Zhu, Xuejun, Downey, Jordan, Khalaf, Ryan, Martin, Joelle, Koshino, Hiroyuki, Zhang, Wenjun
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 03.07.2017
• Subjects: Actinobacteria; Actinobacteria - enzymology; Actinobacteria - genetics; Acylation; Amino groups; Bacteria; Biological Sciences; Biological Transport; Biosynthesis; Catalysis; Chromatography; Chromatography, Ion Exchange; Enzymes; Escherichia coli - enzymology; Escherichia coli - genetics; Fatty Acids - chemistry; Gene clusters; Gene Deletion; Homology; Iron; Lipopeptides; Lipopeptides - biosynthesis; Lysine - chemistry; Metal concentrations; Metals; Multigene Family; Mutation; Mycobacterium marinum; Mycobacterium marinum - enzymology; Mycobacterium marinum - genetics; Mycobacterium tuberculosis; Mycobacterium tuberculosis - enzymology; Mycobacterium tuberculosis - genetics; Oxidase; Peptide Synthases - genetics; Peptide Synthases - metabolism; Peptides; Protein Domains; Proteins; Ribosomes - chemistry; Thioesterase; Tuberculosis; mycobacteria; biosynthetic enzymes; metal transport
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1705016114

A putative lipopeptide biosynthetic gene cluster is conserved in many species of Actinobacteria, including Mycobacterium tuberculosis and M. marinum, but the specific function of the encoding proteins has been elusive. Using both in vivo heterologous reconstitution and in vitro biochemical analyses, we have revealed that the five encoding biosynthetic enzymes are capable of synthesizing a family of isonitrile lipopeptides (INLPs) through a thio-template mechanism. The biosynthesis features the generation of isonitrile from a single precursor Gly promoted by a thioesterase and a nonheme iron(II)-dependent oxidase homolog and the acylation of both amino groups of Lys by the same isonitrile acyl chain facilitated by a single condensation domain of a nonribosomal peptide synthetase. In addition, the deletion of INLP biosynthetic genes in M. marinum has decreased the intracellular metal concentration, suggesting the role of this biosynthetic gene cluster in metal transport.