Streit W R, Phillips D A
Department of Agronomy and Range Science, University of California, Davis 95616, USA.
Mol Plant Microbe Interact. 1997 Sep;10(7):933-7. doi: 10.1094/MPMI.1997.10.7.933.
A novel biotin-inducible DNA locus, bioS, was found in Rhizobium meliloti 1021 by mutation with a transposable promoter probe. The promoterless nptII reporter responded to 40 nM biotin with a sixfold increase in NPTII protein. Stationary-phase mutant cells accumulated 50% more 14C-biotin than corresponding wild-type cells. The prototrophic mutant competed equally with the wild type in biotin-free medium but poorly when 40 nM biotin was present. The 588-bp bioS is located among three genes showing homology to survival operons of other bacteria, and it may be part of a system that R. meliloti uses to respond to plant biotin signals.
通过用可转座启动子探针进行诱变，在苜蓿根瘤菌1021中发现了一个新的生物素诱导型DNA位点bioS。无启动子的nptII报告基因对40 nM生物素产生反应，NPTII蛋白增加了六倍。稳定期突变细胞比相应的野生型细胞积累的14C-生物素多50%。原养型突变体在无生物素培养基中与野生型竞争能力相当，但在存在40 nM生物素时竞争力较差。588 bp的bioS位于与其他细菌生存操纵子具有同源性的三个基因之间，它可能是苜蓿根瘤菌用于响应植物生物素信号的系统的一部分。
