The catalase and superoxide dismutase genes are transcriptionally up-regulated upon oxidative stress in the strictly anaerobic archaeon Methanosarcina barkeri
The catalase and superoxide dismutase genes are transcriptionally up-regulated upon oxidative stress in the strictly anaerobic archaeon Methanosarcina barkeri
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DOI：
10.1099/mic.0.28542-0
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发表时间：
2006-06-01
期刊：
影响因子：
2.8
通讯作者：
Eggen, Rik I. L.
中科院分区：
文献类型：
--
作者：
Brioukhanov, Andrei L.;Netrusov, Alexander I.;Eggen, Rik I. L.
巴氏甲烷八叠球菌是一种严格厌氧的产甲烷古菌，能在氧化胁迫下存活。氧化应激剂百草枯（PQ）抑制M. barkeri，浓度为50-200 μ M。过氧化氢（H_2O_2）在0.4-1.6 mM浓度下抑制生长。在H2 O2胁迫（1.3 mM H2 O2，2-4 h暴露）期间barkeri增加约3倍，在超氧化物胁迫（160 μ M PQ，2 h暴露）期间增加近2倍。PQ（160 μ M，2-4小时暴露）和H2 O2（1.3 mM，2小时暴露）也影响超氧化物歧化酶活性的无细胞提取物中的M。巴克里。斑点印迹分析进行总RNA分离H2 O2和PQ暴露的文化，使用标记的内部DNA片段的SOD和KAT基因。结果表明，过氧化氢，而不是PQ强烈诱导上调的kat基因。PQ和较小程度的H2 O2诱导超氧化物歧化酶的表达。结果表明，M. barkeri对不同氧化胁迫的反应。
Methanosarcina barkeri is a strictly anaerobic methanogenic archaeon, which can survive oxidative stress. The oxidative stress agent paraquat (PQ) suppressed growth of M. barkeri at concentrations of 50-200 mu M. Hydrogen peroxide (H2O2) inhibited growth at concentrations of 0.4-1.6 mM. Catalase activity in cell-free extracts of M. barkeri increased about threefold during H2O2 stress (1.3 mM H2O2, 2-4 h exposure) and nearly twofold during superoxide stress (160 mu M PQ, 2 h exposure). PQ (160 mu M, 2-4 h exposure) and H2O2 (1.3 mM, 2 h exposure) also influenced superoxide dismutase activity in cell-free extracts of M. barkeri. Dot-blot analysis was performed on total RNA isolated from H2O2- and PQ-exposed cultures, using labelled internal DNA fragments of the sod and kat genes. It was shown that H2O2 but not PQ strongly induced up-regulation of the kat gene. PQ and to a lesser degree H2O2 induced the expression of superoxide dismutase. The results indicate the regulation of the adaptive response of M. barkeri to different oxidative stresses.