Interaction between DAHP synthase and chorismate mutase endows new regulation on DAHP synthase activity in Corynebacterium glutamicum----中国科学院微生物研究所

科研成果

论文题目:	Interaction between DAHP synthase and chorismate mutase endows new regulation on DAHP synthase activity in Corynebacterium glutamicum
作者:	Li Pan-Pan, Li De-Feng, Liu Di, Liu Yi-Ming, Liu Chang, Liu Shuang-Jiang
联系作者:	Liu Shuang-Jiang
刊物名称:	Applied microbiology and biotechnology
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年份:	2013
影响因子:	3.613
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摘要:	Previous research on Corynebacterium glutamicum revealed that 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DSCg, formerly DS2098) interacts with chorismate mutase (CMCg, formerly CM0819). In this study, we investigated the interaction by means of structure-guided mutation and enzymatic assays. Our results show that the interaction imparted a new mechanism for regulation of DAHP activity: In the absence of CMCg, DSCg activity was not regulated by prephenate, whereas in the presence of CMCg, prephenate markedly inhibited DSCg activity. Prephenate competed with the substrate phosphoenolpyruvate, and the inhibition constant (K i) was determined to be 0.945 mM. Modeling based on the structure of the complex formed between DAHP synthase and chorismate mutase of Mycobacterium tuberculosis predicted the interaction surfaces of the putative DSCg-CMCg complex. The amino acid residues and structural domains that contributed to the interaction surfaces were experimentally identified to be the 212SPAGARYE219 sequence of DSCg and the 60SGGTR64 loop and C-terminus (97RGKLG101) of CMCg.