Characterization of 2-bromoethanesulfonate as a selective inhibitor of the coenzyme m-dependent pathway and enzymes of bacterial aliphatic epoxide metabolism.
Characterization of 2-bromoethanesulfonate as a selective inhibitor of the coenzyme m-dependent pathway and enzymes of bacterial aliphatic epoxide metabolism.
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2-溴乙磺酸盐作为辅酶 m 依赖性途径和细菌脂肪族环氧化物代谢酶的选择性抑制剂的表征。
DOI：
10.1128/jb.00947-06
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发表时间：
2006
影响因子：
3.2
通讯作者：
Ensign,ScottA
中科院分区：
文献类型：
--
作者：
Boyd,JeffreyM;Ellsworth,Ashley;Ensign,ScottA
短链脂肪族烯烃的细菌生长需要辅酶M（CoM）（2-巯基乙磺酸），其作为亲核试剂用于活化和转化由烯烃氧化形成的环氧化物产物为中心代谢物。在目前的工作中，CoM类似物2-溴乙磺酸盐（BES）被证明是一个特定的抑制剂丙烯依赖的生长和环氧丙烷代谢的黄曲霉菌株Py 2。BES（低[毫摩尔]浓度）完全阻止了丙烯的生长，但对丙酮或正丙醇的生长没有影响。由细胞消耗的丙烯在很大程度上不受BES的存在下，但环氧丙烷积累在培养基中的BES存在的时间依赖性的方式。加入BES细胞导致环氧丙烷降解活性的时间依赖性损失，在去除BES和加入CoM后恢复。细胞暴露于BES导致环氧丙烷依赖的CO2固定活性的损失，只有在合成新的蛋白质后才能恢复。加入BES细胞提取物导致环氧羧化酶活性的不可逆损失，通过加入纯化的2-酮丙基-CoM羧化酶/氧化还原酶（2-KPCC）（环氧化物羧化的末端酶），而不是通过加入环氧烷烃：CoM转移酶或2-羟丙基-CoM脱氢酶（催化前两个环氧化物羧化反应的酶），环氧羧化酶活性得到恢复。的丙烯氧化放线菌Rhodococcus rhodochrous菌株B276的比较研究表明，BES是一种抑制剂的丙烯依赖性生长在这种有机体，以及但不是一个抑制剂的CoM独立的生长与丙烷。这些结果表明，BES抑制丙烯依赖的增长和环氧化物代谢的关键CO2固定酶2-KPCC的不可逆失活。
Bacterial growth with short-chain aliphatic alkenes requires coenzyme M (CoM) (2-mercaptoethanesulfonic acid), which serves as the nucleophile for activation and conversion of epoxide products formed from alkene oxidation to central metabolites. In the present work the CoM analog 2-bromoethanesulfonate (BES) was shown to be a specific inhibitor of propylene-dependent growth of and epoxypropane metabolism byXanthobacter autotrophicusstrain Py2. BES (at low [millimolar] concentrations) completely prevented growth with propylene but had no effect on growth with acetone orn-propanol. Propylene consumption by cells was largely unaffected by the presence of BES, but epoxypropane accumulated in the medium in a time-dependent fashion with BES present. The addition of BES to cells resulted in time-dependent loss of epoxypropane degradation activity that was restored upon removal of BES and addition of CoM. Exposure of cells to BES resulted in a loss of epoxypropane-dependent CO2fixation activity that was restored only upon synthesis of new protein. Addition of BES to cell extracts resulted in an irreversible loss of epoxide carboxylase activity that was restored by addition of purified 2-ketopropyl-CoM carboxylase/oxidoreductase (2-KPCC), the terminal enzyme of epoxide carboxylation, but not by addition of epoxyalkane:CoM transferase or 2-hydroxypropyl-CoM dehydrogenase, the enzymes which catalyze the first two reactions of epoxide carboxylation. Comparative studies of the propylene-oxidizing actinomyceteRhodococcus rhodochrousstrain B276 showed that BES is an inhibitor of propylene-dependent growth in this organism as well but is not an inhibitor of CoM-independent growth with propane. These results suggest that BES inhibits propylene-dependent growth and epoxide metabolism via irreversible inactivation of the key CO2-fixing enzyme 2-KPCC.