Chemotaxis of Pseudomonas aeruginosa: involvement of methylation.
Chemotaxis of Pseudomonas aeruginosa: involvement of methylation.
复制标题
铜绿假单胞菌的趋化性：甲基化的参与。
DOI：
10.1128/jb.154.2.780-786.1983
复制
发表时间：
1983
影响因子：
3.2
通讯作者：
Montie,TC
中科院分区：
文献类型：
--
作者：
Craven,RC;Montie,TC
研究了蛋白质甲基转移系统在铜绿假单胞菌趋化性中的作用。当甲硫氨酸营养缺陷型铜绿假单胞菌的甲硫氨酸饥饿，对丝氨酸的趋化性，通过定量毛细管测定，减少了80%，而背景运动不受影响或增加。当用L-[甲基-3H]甲硫氨酸标记未饥饿的细菌时，鉴定出分子量为73，000的标记物质，其响应于L-丝氨酸的刺激而甲基化。在适当的电泳条件下，73，000分子量的物质被分解成两条带，这两条带都对L-丝氨酸、L-精氨酸和α-氨基异丁酸酯（AIB）的刺激有反应，甲基标记的掺入增加。精氨酸，引起最强的趋化反应，在毛细管测定，也刺激了最大的甲基化反应。73，000分子量物质的甲基化在AIB刺激后10分钟达到最大值，并且在去除AIB后恢复到未刺激的水平。用S-腺苷[甲基-3H]甲硫氨酸体外标记细胞提取物表明，73，000分子量物质通过S-腺苷甲硫氨酸介导的反应被甲基化。这些结果表明，铜绿假单胞菌对氨基酸的趋化性是由类似于肠道细菌的甲基接受趋化蛋白的动态甲基化和去甲基化介导的。
The involvement of a protein methyl transfer system in the chemotaxis of Pseudomonas aeruginosa was investigated. When a methionine auxotroph of P. aeruginosa was starved for methionine, chemotaxis toward serine, measured by a quantitative capillary assay, was reduced 80%, whereas background motility was unaffected or increased. When unstarved bacteria were labeled with L-[methyl-3H]methionine, a labeled species of 73,000 molecular weight which was methylated in response to stimulation by L-serine was identified. Under appropriate electrophoretic conditions, the 73,000 molecular weight species was resolved into two bands, both of which responded to stimulation by L-serine, L-arginine, and alpha-aminoisobutyrate (AIB) with an increased incorporation of methyl label. Arginine, which elicited the strongest chemotactic response in the capillary assay, also stimulated the greatest methylation response. Methylation of the 73,000 molecular weight species reached a maximum 10 min after stimulation by AIB and returned to the unstimulated level upon removal of the AIB. In vitro labeling of cell extracts with S-adenosyl[methyl-3H]methionine indicated that the 73,000 molecular weight species are methylated by an S-adenosylmethionine-mediated reaction. These results indicate that chemotaxis of P. aeruginosa toward amino acids is mediated by dynamic methylation and demethylation of methyl-accepting chemotaxis proteins analogous to those of the enteric bacteria.