The nine genes of the Nocardia lactamdurans cephamycin cluster are transcribed into large mRNAs from three promoters, two of them located in a bidirectional promoter region.
The nine biosynthesis genes of the Nocardia lactamdurans cephamycin cluster are expressed as three different mRNAs initiating at promoters latp, cefDp, and pcbABp, as shown by low-resolution S1 nuclease protection assays and Northern blotting analysis. Bidirectional expression occurred from divergent promoters (latp and cefDp) located in a 629-bp intergenic region that contains three heptameric direct repeats similar to those recognized by members of the SARP (Streptomyces antibiotic regulatory proteins) family. The lat gene is transcribed in a single monocistronic transcript initiating at latp. A second unusually long polycistronic mRNA (more than 16 kb) corresponding to six biosynthesis genes (pcbAB, pcbC, cmcI, cmcJ, cefF, and cmcH) started at pcbABp. A third polycistronic mRNA corresponding to the cefD and cefE genes started at cefDp.
Enguita
F J
FJ
Area of Microbiology, Faculty of Biology, University of León, 24071 León, Spain.
Coque
J J
JJ
Liras
P
P
Martin
J F
JF
D001483:Base Sequence; D002513:Cephamycins / Q000096:biosynthesis*; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D005810:Multigene Family; D009615:Nocardia / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D015183:Restriction Mapping; D014158:Transcription, Genetic
D002513:Cephamycins; D012329:RNA, Bacterial; D012333:RNA, Messenger