Characterization of the coformycin biosynthetic gene cluster in Streptomyces kaniharaensis

Coformycin and pentostatin are structurally related N-nucleoside inhibitors of adenosine deaminase characterized by an unusual 1,3-diazepine nucleobase. Herein, the cof gene cluster responsible for coformycin biosynthesis is identified. Reconstitution of the coformycin biosynthetic pathway in vitro demonstrates that it overlaps significantly with the early stages of l-histidine biosynthesis. Committed entry into the coformycin pathway takes place via conversion of a shared branch point intermediate to 8-ketocoformycin-5′-monophosphate catalyzed by CofB, which is a homolog of succinylaminoimidazolecarboxamide ribotide (SAICAR) synthetase. This reaction appears to proceed via a Dieckmann cyclization and a retro-aldol elimination, releasing ammonia and D-erythronate-4-phosphate as coproducts. Completion of coformycin biosynthesis involves reduction and dephosphorylation of the CofB product, with the former reaction being catalyzed by the NADPH-dependent dehydrogenase CofA. CofB also shows activation by adenosine triphosphate (ATP) despite the reaction requiring neither a phosphorylated nor an adenylated intermediate. This may serve to help regulate metabolic partitioning between the l-histidine and coformycin pathways.

Download Full-text

Biosynthesis of the uridine-derived nucleoside antibiotic A-94964: identification and characterization of the biosynthetic gene cluster provide insight into the biosynthetic pathway

Organic & Biomolecular Chemistry ◽

10.1039/c8ob02765j ◽

2019 ◽

Vol 17 (3) ◽

pp. 461-466 ◽

Cited By ~ 5

Author(s):

Taro Shiraishi ◽

Makoto Nishiyama ◽

Tomohisa Kuzuyama

Keyword(s):

Gene Cluster ◽

In Silico ◽

Biosynthetic Pathway ◽

Gene Deletion ◽

Biosynthetic Gene Cluster ◽

Biosynthetic Gene ◽

Identification And Characterization ◽

Insight Into

The biosynthetic pathway of the uridine-derived nucleoside antibiotic A-94964 was proposed via in silico analysis coupled with gene deletion experiments.

Download Full-text

Cloning and Characterization of the Biosynthetic Gene Cluster for Tomaymycin, an SJG-136 Monomeric Analog

Applied and Environmental Microbiology ◽

10.1128/aem.02325-08 ◽

2009 ◽

Vol 75 (9) ◽

pp. 2958-2963 ◽

Cited By ~ 65

Author(s):

Wei Li ◽

ShenChieh Chou ◽

Ankush Khullar ◽

Barbara Gerratana

Keyword(s):

Cluster Analysis ◽

Gene Cluster ◽

Biosynthetic Pathway ◽

Biosynthetic Gene Cluster ◽

Gene Replacement ◽

Biosynthetic Gene

ABSTRACT Tomaymycin produced by Streptomyces achromogenes is a naturally produced pyrrolobenzodiazepine (PBD). The biosynthetic gene cluster for tomaymycin was identified and sequenced. The gene cluster analysis reveals a novel biosynthetic pathway for the anthranilate moiety of PBDs. Gene replacement and chemical complementation studies were used to confirm the proposed biosynthetic pathway.

Download Full-text

The role of the TetR-family transcriptional regulator Aur1R in negative regulation of the auricin gene cluster in Streptomyces aureofaciens CCM 3239

Microbiology ◽

10.1099/mic.0.037895-0 ◽

2010 ◽

Vol 156 (8) ◽

pp. 2374-2383 ◽

Cited By ~ 29

Author(s):

Renata Novakova ◽

Peter Kutas ◽

Lubomira Feckova ◽

Jan Kormanec

Keyword(s):

Gene Cluster ◽

Biosynthetic Gene Cluster ◽

Transcriptional Repressors ◽

Biosynthetic Gene ◽

Response Regulators ◽

Streptomyces Aureofaciens ◽

Two Component Signal Transduction

Two regulatory genes, aur1P and aur1R, have been previously identified upstream of the aur1 polyketide gene cluster involved in biosynthesis of the angucycline-like antibiotic auricin in Streptomyces aureofaciens CCM 3239. The aur1P gene encodes a protein similar to the response regulators of bacterial two-component signal transduction systems and has been shown to specifically activate expression of the auricin biosynthetic genes. The aur1R gene encodes a protein homologous to transcriptional repressors of the TetR family. Here we describe the characterization of the aur1R gene. Expression of the gene is directed by a single promoter, aur1Rp, which is induced just before stationary phase. Disruption of aur1R in S. aureofaciens CCM 3239 had no effect on growth and differentiation. However, the disrupted strain produced more auricin than its parental wild-type S. aureofaciens CCM 3239 strain. Transcription from the aur1Ap and aur1Pp promoters, directing expression of the first biosynthetic gene in the auricin gene cluster and the pathway-specific transcriptional activator, respectively, was increased in the S. aureofaciens CCM 3239 aur1R mutant strain. However, Aur1R was shown to bind specifically only to the aur1Pp promoter in vitro. This binding was abolished by the addition of auricin and/or its intermediates. The results indicate that the Aur1R regulator specifically represses expression of the aur1P gene, which encodes a pathway-specific activator of the auricin biosynthetic gene cluster in S. aureofaciens CCM 3239, and that this repression is relieved by auricin or its intermediates.

Download Full-text