title: Transductional analysis of chloramphenicol biosynthesis genes in Streptomyces venezuelae.
abstract: Auxotrophs isolated from two chloramphenicol-nonproducing mutants of Streptomyces venezuelae included three requiring pyridoxal (Pxl-), VS248 (cml-11 pdx-2), VS253 (cml-11 pdx-3), and VS258 (cml-12 pdx-4), and one requiring thiosulfate, VS263 (cml-12 cys-28). Results of SV1-mediated transductions were consistent with the relative marker order cys-28-cml-12-cml-11-pdx-2,3,4,5, all of which were cotransducible and must therefore span less than 45 kilobases of DNA, the approximate length of DNA packaged by SV1. cys-28 was also cotransducible with arg-4 and arg-6, but arg and pdx were not cotransducible. Results of crosses with donors carrying any one of 11 cml mutations were consistent with the location of all cml mutations between cys-28 and pdx markers. Also, a new Pxl- auxotroph (pdx-6) and two new Cml- mutants were recovered after localized hydroxylamine mutagenesis of a cys-28 cml+ strain derived from VS263 by transduction.
mesh_terms: D002701:Chloramphenicol / Q000096:biosynthesis*; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D005798:Genes, Bacterial; D005819:Genetic Markers; D009154:Mutation; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism; D014161:Transduction, Genetic
chemical_list: D005819:Genetic Markers; D002701:Chloramphenicol