Energy metabolism and alginate biosynthesis in Pseudomonas aeruginosa: role of the tricarboxylic acid cycle.
Energy metabolism and alginate biosynthesis in Pseudomonas aeruginosa: role of the tricarboxylic acid cycle.
复制标题
铜绿假单胞菌的能量代谢和藻酸盐生物合成：三羧酸循环的作用。
DOI：
10.1128/jb.176.19.6023-6029.1994
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发表时间：
1994
影响因子：
3.2
通讯作者：
Chakrabarty,AM
中科院分区：
文献类型：
--
作者：
Schlictman,D;Kavanaugh-Black,A;Shankar,S;Chakrabarty,AM
Infection with mucoid, alginate-producing strains of Pseudomonas aeruginosa is the leading cause of mortality among patients with cystic fibrosis. Alginate production by P. aeruginosa is not constitutive but is triggered by stresses such as starvation. The algR2 (also termed algQ) gene has been previously identified as being necessary for mucoidy; an algR2 mutant strain is unable to produce alginate when grown at 37 degrees C. We show here that the levels of phosphorylated succinyl coenzyme A synthetase (Scs) and nucleoside diphosphate kinase (Ndk), which form a complex in P. aeruginosa, are reduced in the algR2 mutant. We were able to correlate the lower level of phosphorylated Scs with a decrease in Scs activity. Western blots (immunoblots) also showed a decreased level of Ndk in the algR2 mutant, but the presence of another kinase activity sensitive to Tween 20 provides the missing Ndk function. The effect of AlgR2 on tricarboxylic acid (TCA) cycle enzymes appears to be specific for Scs, since none of the other TCA cycle enzymes measured showed a significant decrease in activity. Furthermore, the ability of the algR2 mutant to grow on TCA cycle intermediates, but not glucose, is impaired. These data indicate that AlgR2 is responsible for maintaining proper operation of the TCA cycle and energy metabolism.
