Novel acetone metabolism in a propane-utilizing bacterium, Gordonia sp strain TY-5
Novel acetone metabolism in a propane-utilizing bacterium, Gordonia sp strain TY-5
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DOI：
10.1128/jb.01054-06
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发表时间：
2007-02-01
影响因子：
3.2
通讯作者：
Sakai, Yasuyoshi
中科院分区：
文献类型：
--
作者：
Kotani, Tetsuya;Yurimoto, Hiroya;Sakai, Yasuyoshi
在利用丙烷的戈登氏菌菌株TY-5中，丙烷被氧化成2-丙醇，然后进一步氧化成丙酮。在这项研究中，丙酮的后续代谢进行了研究。丙酮诱导的蛋白质被发现在丙酮诱导的细胞提取物中，并命名为acmAB的基因簇的丙酮诱导的蛋白质的N-末端氨基酸序列的基础上克隆。acmA和acmB基因分别编码Baeyer-Villiger单加氧酶（BVMO）和酯酶。从丙酮诱导的Gordonia sp.菌株TY-5的细胞中纯化acmA编码的BVMO，并对其进行表征。BVMO对线性酮（C-3至C-10）和环状酮（C-4至C-8）具有NADPH依赖性氧化活性。表达acmA基因的大肠杆菌将丙酮氧化为乙酸甲酯，而表达acmA基因的大肠杆菌将丙酮氧化为乙酸甲酯。表达acmB基因的大肠杆菌水解乙酸甲酯。北方印迹分析表明，多顺反子转录的acmAB基因簇诱导丙烷，2-丙醇，丙酮。这些结果表明acmAB基因产物在丙烷氧化生成丙酮的代谢过程中起重要作用，并阐明了TY-5菌株的丙烷代谢途径（丙烷-> 2-丙醇->丙酮->乙酸甲酯->乙酸+甲醇）。本文提供了BVMO依赖的丙酮代谢的第一个证据。
In the propane-utilizing bacterium Gordonia sp. strain TY-5, propane was shown to be oxidized to 2-propanol and then further oxidized to acetone. In this study, the subsequent metabolism of acetone was studied. Acetone-induced proteins were found in extracts of cells induced by acetone, and a gene cluster designated acmAB was cloned on the basis of the N-terminal amino acid sequences of acetone-induced proteins. The acmA and acmB genes encode a Baeyer-Villiger monooxygenase (BVMO) and esterase, respectively. The BVMO encoded by acmA was purified from acetone-induced cells of Gordonia sp. strain TY-5 and characterized. The BVMO exhibited NADPH-dependent oxidation activity for linear ketones (C-3 to C-10) and cyclic ketones (C-4 to C-8). Escherichia coli expressing the acmA gene oxidized acetone to methyl acetate, and E. coli expressing the acmB gene hydrolyzed methyl acetate. Northern blot analyses revealed that polycistronic transcription of the acmAB gene cluster was induced by propane, 2-propanol, and acetone. These results indicate that the acmAB gene products play an important role in the metabolism of acetone derived from propane oxidation and clarify the propane metabolism pathway of strain TY-5 (propane -> 2-propanol -> acetone -> methyl acetate -> acetic acid + methanol). This paper provides the first evidence for BVMO-dependent acetone metabolism.