title: A plasmid involved in chloramphenicol production in Streptomyces venezuelae: evidence from genetic mapping.
abstract: To test the hypothesis that chloramphenicol production in Streptomyces venezuelae depends on the presence of a plasmid, mapping analysis was carried out by using eight markers in addition to chloramphenicol production and melanoid pigment formation. The sequence of the eight markers was determined on a circular linkage map as follows: -his-ade-str-leu-lys-met-ilv-pro-(his-). This sequence resulted in the frequency of quadruple crossover (q.c.o.) recombinants having the lowest value, 3-2 to 4-9%. However, the character of chloramphenicol non-production, which was obtained by incubating mycelia with acriflavin, was not required to explain the results. From these results and other tests, it is concluded that chloramphenicol production is controlled by a plasmid. This plasmid appeared to be non-transferable in conjugation.
mesh_terms: D000167:Acriflavine / Q000494:pharmacology; D002701:Chloramphenicol / Q000096:biosynthesis*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D005111:Extrachromosomal Inheritance; D008040:Genetic Linkage; D010860:Pigments, Biological / Q000096:biosynthesis; D010957:Plasmids / Q000187:drug effects; D011995:Recombination, Genetic; D013302:Streptomyces / Q000378:metabolism*
chemical_list: D010860:Pigments, Biological; D000167:Acriflavine; D002701:Chloramphenicol