...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >sn-Glycerol-3-phosphate transport in Salmonella typhimurium.
【24h】

sn-Glycerol-3-phosphate transport in Salmonella typhimurium.

机译：sn-甘油-3-磷酸在鼠伤寒沙门氏菌中的转运。

获取原文
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Salmonella typhimurium contains a transport system for sn-glycerol-3-phosphate that is inducible by growth on glycerol and sn-glycerol-3-phosphate. In fully induced cells, the system exhibited an apparent Km of 50 microM and a Vmax of 2.2 nmol/min . 10(8) cells. The corresponding system in Escherichia coli exhibits, under comparable conditions, a Km of 14 microM and a Vmax of 2.2 nmol/min . 10(8) cells. Transport-defective mutants were isolated by selecting for resistance against the antibiotic fosfomycin. They mapped in glpT at 47 min in the S. typhimurium linkage map, 37% cotransducible with gyrA. In addition to the glpT-dependent system, S. typhimurium LT2 contains, like E. coli, a second, ugp-dependent transport system for sn-glycerol-3-phosphate that was derepressed by phosphate starvation. A S. typhimurium DNA bank containing EcoRI restriction fragments in phage lambda gt7 was used to clone the glpT gene in E. coli. Lysogens that were fully active in the transport of sn-glycerol-3-phosphate with a Km of 33 microM and a Vmax of 2.0 nmol/min . 10(8) cells were isolated in a delta glpT mutant of E. coli. The EcoRI fragment harboring glpT was 3.5 kilobases long and carried only part of glpQ, a gene distal to glpT but on the same operon. The fragment was subcloned in multicopy plasmid pACYC184. Strains carrying this hybrid plasmid produced large amounts of cytoplasmic membrane protein with an apparent molecular weight of 33,000, which was identified as the sn-glycerol-3-phosphate permease. Its properties were similar to the corresponding E. coli permease. The presence of the multicopy glpT hybrid plasmid had a strong influence on the synthesis or assembly of other cell envelope proteins of E. coli. For instance, the periplasmic ribose-binding protein was nearly absent. On the other hand, the quantity of an unidentified E. coli outer membrane protein usually present only in small amounts increased.
机译：鼠伤寒沙门氏菌包含一个针对3-磷酸甘油酯的转运系统，该转运系统可以通过在甘油和3-磷酸甘油甘油上的生长来诱导。在完全诱导的细胞中，该系统表现出50 microM的表观Km和2.2 nmol / min的Vmax。 10（8）个单元格。在相当的条件下，大肠杆菌中的相应系统的Km为14 microM，Vmax为2.2 nmol / min。 10（8）个单元格。通过选择对抗生素磷霉素的抗性来分离运输缺陷的突变体。他们在鼠伤寒沙门氏菌连锁图中第47分钟以glpT定位，与gyrA可共转导37％。除依赖于glpT的系统外，鼠伤寒沙门氏菌LT2还包含像大肠杆菌一样的第二种依赖ugp的sn-甘油3-磷酸转运系统，该系统因磷酸盐饥饿而受到抑制。使用在噬菌体λgt7中含有EcoRI限制片段的鼠伤寒沙门氏菌DNA库在大肠杆菌中克隆glpT基因。溶菌原在以33 microM的Km和2.0 nmol / min的Vmax转运Sn-甘油3-磷酸时具有完全的活性。在大肠杆菌的ΔglpT突变体中分离出10（8）个细胞。带有glpT的EcoRI片段长3.5千碱基，仅携带glpQ的一部分，后者是glpT的远端基因，但在同一操纵子上。将该片段亚克隆到多拷贝质粒pACYC184中。携带该杂种质粒的菌株产生大量的表观分子量为33,000的细胞质膜蛋白，被鉴定为sn-甘油3-磷酸通透酶。其性质类似于相应的大肠杆菌通透酶。多拷贝glpT杂合质粒的存在对大肠杆菌的其他细胞包膜蛋白的合成或组装有强烈影响。例如，几乎不存在周质核​​糖结合蛋白。另一方面，通常仅少量存在的未鉴定的大肠杆菌外膜蛋白的量增加。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号