Putative lmbI and lmbH genes form a single lmbIH ORF in Streptomyces lincolnensis type strain ATCC 25466.
The lincomycin-production gene cluster of the industrial overproduction strain Streptomyces lincolnensis 78-11 has been sequenced (Peschke et al. 1995) and twenty-seven putative open reading frames with biosynthetic or regulatory functions (lmb genes) identified. Two distinct hypothetical genes, lmbI and lmbH, were found downstream of the lmbJ gene, coding for LmbJ protein, which is believed to participate in the last lincomycin biosynthetic step, i.e. conversion of N-demethyllincomycin (NDL) to lincomycin. In the present study, we demonstrate the presence of a single larger open reading frame, called lmbIH, in the lincomycin low-production type strain Streptomyces lincolnensis ATCC 25466, instead of two smaller lmbI and lmbH genes. The product, LmbIH, is a protein of an unknown function and is homologous with the T1dD protein family. Escherichia coli T1dD protein was previously shown to be involved in the control of DNA gyrase by LetD protein. Moreover, our experiments indicate co-regulation of lmbJ and lmbIH expression. This translation coupling probably reflects an eight nucleotide overlap between the lmbJ and lmbIH genes, as well as the lack of a Shine-Dalgarno sequence upstream of the lmbIH gene.
Janata
J
J
Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague.
Najmanová
L
L
Novotná
J
J
Holá
K
K
Felsberg
J
J
Spízek
J
J
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008034:Lincomycin / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D005810:Multigene Family; D016366:Open Reading Frames / Q000235:genetics*; D014176:Protein Biosynthesis; D017422:Sequence Analysis, DNA; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C455465:LmbIH protein, Streptomyces lincolnensis; C098431:TldD protein, E coli; D008034:Lincomycin