Calcium ions are involved in Escherichia coli chemotaxis.
Calcium ions are involved in Escherichia coli chemotaxis.
复制标题
钙离子参与大肠杆菌趋化性。
DOI：
10.1073/pnas.89.24.11804
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发表时间：
1992
影响因子：
11.1
通讯作者：
Adler,J
中科院分区：
文献类型：
--
作者：
Tisa,LS;Adler,J
大肠杆菌在约90 nM下调节细胞内游离Ca 2 +[Gangola，P. &罗森，B. P.（1987）J.Biol.Chem.262，12570-12574]。为了增加细胞内游离Ca 2+，将nitr-5/Ca 2+（一种“笼状”Ca 2+化合物）电穿孔到细胞中，然后通过暴露于370-nm光降低其对Ca 2+的亲和力。在释放Ca 2+离子时，细胞翻滚。对突变株的研究表明，受体蛋白（甲基接受趋化蛋白，MCP）不是Ca（2+）诱导的翻滚所必需的，但需要CheA，CheW和CheY蛋白。用DM-硝基酚/Ca 2+获得了类似的结果，DM-硝基酚/Ca 2+是另一种笼状钙化合物，在340 nm照射时释放Ca 2+。重氮-2，一种笼状的钙离子螯合剂，在340 nm的光照下吸收钙离子，用于减少细胞内游离钙离子，这导致了平稳的游泳。
Escherichia coli regulates intracellular free Ca2+ at about 90 nM [Gangola, P. & Rosen, B. P. (1987) J. Biol. Chem. 262, 12570-12574]. To increase intracellular free Ca2+, nitr-5/Ca2+, a "caged" Ca2+ compound, was electroporated into cells and then its affinity for Ca2+ was reduced by exposure to 370-nm light. Upon release of the Ca2+ ions, the cells tumbled. Studies on mutant strains showed that the receptor proteins (methyl-accepting chemotaxis proteins, MCPs) were not required for the Ca(2+)-induced tumbling but that CheA, CheW, and CheY proteins were required. Similar results were obtained with DM-nitrophen/Ca2+, another caged calcium compound that releases Ca2+ upon illumination at 340 nm. Diazo-2, a caged Ca2+ chelator that takes up Ca2+ upon illumination at 340 nm, was used to decrease intracellular free Ca2+, and this caused smooth swimming.