[光滑球拟酵母中α-酮戊二酸脱氢酶复合体的生理功能]

[Physiological function of alpha-ketoglutarate dehydrogenase complex in Torulopsis glabrata].

作者信息

Zhang Dandan, Liu Liming, Du Guocheng, Chen Jian

机构信息

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.

出版信息

Wei Sheng Wu Xue Bao. 2009 Dec;49(12):1584-9.

PMID:20222442

Abstract

OBJECTIVE

We studied the physiological function of alpha-ketoglutarate dehydrogenase complex (KGDH) on the metabolism of Torulopsis glabrata.

METHODS

With manipulation of KGDH in Torulopsis glabrata, we screened a mutant strain T. glabrata kgd1:: kan, in which the kgd1 gene encoding the E1 subunit of KGDH was deleted.

RESULTS

Disruption of KGDH resulted in: (a) the enhancement of glyoxalate pathway as a complementarity for carbon metabolism in TCA cycle; (b) compared with that of the control, the ratio of NADH/NAD + and ATP/ADP decreased by 33.7% and 31.8%, respectively. But the specific activities of pyruvate dehydrogenase, isocitrate dehydrogenase and malate dehydrogenase increased by 58.1%, 33.3% and 32.5%, respectively; (c) the intracellular concentration of pyruvate was reduced by 49.9%, while the intracellular concentration of succinate, malate and alpha-ketoglutarate was higher 172.7%, 66.1% and 41.1% than the corresponding values of the control; (d) The content of pyruvate-family amino acid was 29.3% lower while the level of glutamate-family amino acid and aspartate-family amino acid were 34.7% and 26.8% higher than that of control.

CONCLUSIONS

Those results present here demonstrated that alpha-ketoglutarate dehydrogenase complex plays essential role on the metabolism of yeast.

摘要

目的

我们研究了α-酮戊二酸脱氢酶复合体（KGDH）对光滑球拟酵母代谢的生理功能。

方法

通过对光滑球拟酵母中的KGDH进行操作，我们筛选出了一个突变菌株光滑球拟酵母kgd1::kan，其中编码KGDH E1亚基的kgd1基因被删除。

结果

KGDH的破坏导致：（a）乙醛酸途径增强，作为三羧酸循环中碳代谢的补充；（b）与对照相比，NADH/NAD +和ATP/ADP的比率分别下降了33.7%和31.8%。但丙酮酸脱氢酶、异柠檬酸脱氢酶和苹果酸脱氢酶的比活性分别增加了58.1%、33.3%和32.5%；（c）细胞内丙酮酸浓度降低了49.9%，而琥珀酸、苹果酸和α-酮戊二酸的细胞内浓度分别比对照相应值高172.7%、66.1%和41.1%；（d）丙酮酸家族氨基酸的含量比对照低29.3%，而谷氨酸家族氨基酸和天冬氨酸家族氨基酸的水平分别比对照高34.7%和26.8%。