Rapid attractant-induced changes in methylation of methyl-accepting chemotaxis proteins in Bacillus subtilis.
Rapid attractant-induced changes in methylation of methyl-accepting chemotaxis proteins in Bacillus subtilis.
复制标题
枯草芽孢杆菌中引诱剂诱导的甲基接受趋化蛋白甲基化的快速变化。
DOI：
10.1021/bi00422a024
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发表时间：
1988
期刊：
影响因子：
2.9
通讯作者：
Ordal,GW
中科院分区：
文献类型：
--
作者：
Thoelke,MS;Parker,HM;Ordal,EA;Ordal,GW
摘要：在枯草芽孢杆菌中，加入趋化性引诱剂会立即改变甲基接受趋化蛋白（MCP）上甲基的分布，而在大肠杆菌中，它会导致整个适应期发生的变化。因此，B中的甲基化发生变化。枯草芽孢杆菌可能与兴奋有关，而不是适应。如果标记的细胞暴露于过量的非放射性甲硫氨酸，那么引诱剂会立即导致50%的MCP去标记，这表明发生了通过MCP的甲基通量。甲醇在适应期的释放速率很高，可能反映了某种物质的去甲基化作用，从而引起了适应。许多放射性甲基从MCP中立即丢失，但随着甲醇的出现才缓慢出现，这一事实与它们从MCP转移到甲醇产生的载体的假设一致。这种载体的去甲基化可能引起适应。（趋化性是一种原始的感觉机制，细菌借此能够感知其环境并向有利条件迁移。在细胞恢复到刺激前行为之前，化学引诱剂引起一段时间的平稳游泳（贝格和特德斯科，1974;奥达尔，1975）。在大肠杆菌中，已经证明在此期间，游泳引诱剂导致甲醇生产停止，
Revised Manuscript Received June 23, 1988 abstract: In Bacillus subtilis, addition of chemotactic attractant causes an immediate change in distribution of methyl groups on methyl-accepting chemotaxis proteins (MCPs), whereas in Escherichia coli, it causes changes that occur throughout the adaptation period. Thus, methylation changes in B. subtilis are probably related to excitation, not adaptation. If labeled cells are exposed to excess nonradioactive methionine, then attractant causes immediate 50% delabeling of the MCPs, suggesting that a flux of methyl groups through the MCPs occurs. Methanol is given off at a high rate during the adaptation period and probably reflects demethylation of some substance to bring about adaptation. The fact that many radioactive methyl groups are lost immediatelyfrom the MCPs but only slowly arise as methanol is consistent with the hypothesis that they are transferred from the MCPs to a carrier from which methanol arises. Demethylation of this carrier may cause adaptation.(Chemotaxis is a primitive sensory mechanism whereby bacteria are able to sense their environment and migrate to-ward favorable conditions. Chemoattractants cause a period of smooth swimming before the cells return to prestimulus behavior (Berg & Tedesco, 1974; Ordal, 1975). In Escherichia coli, it has been shown that during thisperiod of swimming attractants cause a cessation of methanol production and a