The bialaphos resistance gene (bar) plays a role in both self-defense and bialaphos biosynthesis in Streptomyces hygroscopicus.
We inactivated the bialaphos (BA) resistance gene (bar) of a BA producer, Streptomyces hygroscopicus, by the gene replacement technique. The resulting BA-sensitive mutant (Bar-) was able to produce little BA but considerable amount of an intermediate demethylphosphinothricin (DMPT). The Bar- mutant was still able to convert the N-acetyl derivative (AcDMPT) of DMPT to BA. Introduction of normal bar containing plasmid restored both BA resistance and BA biosynthesis to levels as high as the parental BA producer. By contrast, introducing a multi copy glutamine synthetase gene (glnA) into the Bar- mutant restored BA resistance but not BA production. Thus, the bar gene plays a crucial role in both self-defense and a step of BA biosynthesis in the BA-producing S. hygroscopicus.
Kumada
Y
Y
Pharmaceutical Research Laboratories, Meiji Seika Kaisha, Ltd., Yokohama, Japan.
Anzai
H
H
Takano
E
E
Murakami
T
T
Hara
O
O
Itoh
R
R
Imai
S
S
Satoh
A
A
Nagaoka
K
K
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial / Q000235:genetics; D005798:Genes, Bacterial; D006540:Herbicides / Q000494:pharmacology*; D009154:Mutation; D009943:Organophosphorus Compounds / Q000096:biosynthesis / Q000494:pharmacology*; D010641:Phenotype; D010957:Plasmids; D013302:Streptomyces / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D006540:Herbicides; D009943:Organophosphorus Compounds; C003122:bialaphos