Isolation, Sequencing and Annotation of three genes putatively involved in capreomycidine biosynthesis in Streptomyces ribosidificus NRRL B-11466

Abstract

Capreomycidine is a nonproteinogenic amino acid that is biosynthesized and condensed with other amino acids via a nonribosomal peptide synthase mechanism to form various antibiotics of tuberactinomycin family. This family of peptide antibiotics is of enormous activity against Mycobacterium tuberculosis infections and is particularly used for the treatment of multidrug-resistant tuberculosis, methicillinresistant Staphylococcus aureus strains and vancomycin-resistant enterococci. In this research, isolation, sequencing and annotation of three genes putatively involved in capreomycidine biosynthesis from Streptomyces ribosidificus NRRL B-11466 were carried out. Various heterologous and homologous primers were designed and used in PCR to amplify various homologous DNA fragments. The PCR products were sequenced and the obtained DNA sequences were assembled using the Staden-Package programme into a continuous DNA segment of 3484 bp. The obtained DNA segment was analysed and submitted to the EMBL database under the accession code HQ327309. Analysis of the respective DNA segment revealed three completed open reading frames where the respective gene products showed good amino acid identities to homologous gene products of viomycin-biosynthetic gene cluster. These gene products were putative L-arginine hydroxylase (86% identity), putative capreomycidine synthase (82% identity), and putative permease (85% identity). This is the first report about gene products putatively involved in capreomycidine biosynthesis in Streptomyces ribosidificus. Results obtained from this study will contribute to explore the production of a new peptide antibiotic by Streptomyces ribosidificus, the producer of the aminoglycoside antibiotic ribostamycin.