[Cloning of mitomycin C resistance gene from Streptoverticillium caespitosum ATCC27422 and studying its function].
Streptoverticillium caespitosum is the major producer of anti-cancer drug mitomycin. It demonstrated that there exists a strong restriction system for the transformation of foreign DNA in this strain. Using the blocked mutant S-6 which is sensitive to mitomycin C (MC) and does not produce mitomycin as a recepient and plasmid pIJ699 as vector, the gene library of the strain ATCC27422 was constructed. A clone of mitomycin C resistance gene(mcr) was obtained by screening from this library. The mitomycin C resistance gene cloned on the 6.2 kb fragment of plasmid pLX5 could be expressed in the Strptonmyces lividans TK54. It was the first time to introduce successfully the plasmid pLX5 into the wild type strain ATCC27422 by electroporation technique. And the transformant's resistance to mitomycin C has risen greatly: the MIC has gone up from 200 micrograms/ml to more than 1000 micrograms/ml. The result of fermentation showed that the yield of mitomycin of ATCC27422 harboring plasmid pLX5 was more than the wild strain ATCC27422's. It suggested that there is some relationship between the level of the resistance to mitomycin C and its biosynthesis.
Huang
J
J
Laboratory of Molecular Regulation for Microbial Secondary Metabolism, Shanghai Institute of Plant Physiology, Chinese Academy of Science, Shanghai 200032.
Lu
X
X
Mao
Y
Y
Yang
Y
Y
Jiao
R
R
D000903:Antibiotics, Antineoplastic / Q000096:biosynthesis / Q000494:pharmacology*; D003001:Cloning, Molecular; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D018274:Electroporation; D015870:Gene Expression; D016685:Mitomycin / Q000096:biosynthesis / Q000494:pharmacology*; D010957:Plasmids; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism
D000903:Antibiotics, Antineoplastic; D016685:Mitomycin