CITRATE SUBSTITUTES FOR HOMOCITRATE IN NITROGENASE OF A NIFV MUTANT OF KLEBSIELLA-PNEUMONIAE
CITRATE SUBSTITUTES FOR HOMOCITRATE IN NITROGENASE OF A NIFV MUTANT OF KLEBSIELLA-PNEUMONIAE
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DOI：
10.1021/bi00489a011
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发表时间：
1990-09-18
期刊：
影响因子：
2.9
通讯作者：
BURRIS, RH
中科院分区：
文献类型：
--
作者：
LIANG, JH;MADDEN, M;BURRIS, RH
从肺炎克雷伯菌NIFV突变株分离的固氮酶中提取的一种有机酸被鉴定为柠檬酸。含柠檬酸的固氮酶部分地被CO和某些底物抑制放氢。比较了野生型和NIFV-脱氮酶的最大速度对pH变化的响应。没有观察到酶之间的实质性差异，但有微小的差异。这两种酶在pH 4.8-10范围内都很稳定，但在pH 6.2以下酶活性急剧下降。
An organic acid extracted from purified dinitrogenase isolated from a nifV mutant of Klebsiella pneumoniae has been identified as citric acid. H2 evolution by the citrate-containing dinitrogenase is partially inhibited by CO, and by some substrates for nitrogenase. The response of maximum velocities to changes in pH for both wild-type and the NifV- dinitrogenase was compared. No substantial differences between the enzymes were observed, but there are minor differences. Both enzymes are stable in the pH range 4.8-10, but the enzyme activities dropped dramatically below pH 6.2.