Buttke T M, Ingram L O
Biochemistry. 1978 Nov 28;17(24):5282-6. doi: 10.1021/bi00617a031.
Low concentrations of cerulenin inhibit the growth of Escherichia coli by selectively blocking unsaturated fatty acid synthesis. This inhibition was relieved by unsaturated fatty acid supplements alone but not by saturated fatty acid supplements. The utilization of exogenous unsaturated fatty acids to sustain growth in the presence of cerulenin was confirmed by the analysis of bulk lipid composition. The effects of cerulenin on fatty acid synthesis were examined in vivo by pulse labeling with [14C]acetate and in vitro using [14C]malonyl-coenzyme A. In both cases, unsaturated fatty acid synthesis was inhibited by low concentrations of cerulenin with a stimulation of saturated fatty acid synthesis. Using mutant strains deficient in fatty acid synthesis, the effects of cerulenin on beta-ketoacyl-[acyl-carrier-protein] synthetases I and II were examined. Our results indicate that beta-ketoacyl-[acyl-carrier-protein] synthetase I is more sensitive to inhibition by cerulenin than beta-ketoacyl-[acyl-carrier-protein] synthetase II.
低浓度的浅蓝菌素通过选择性阻断不饱和脂肪酸合成来抑制大肠杆菌的生长。单独添加不饱和脂肪酸可解除这种抑制作用，但添加饱和脂肪酸则不能。通过对总脂质组成的分析证实了在浅蓝菌素存在的情况下利用外源不饱和脂肪酸来维持生长。通过用[14C]乙酸盐进行脉冲标记在体内以及使用[14C]丙二酰辅酶A在体外研究了浅蓝菌素对脂肪酸合成的影响。在这两种情况下，低浓度的浅蓝菌素均抑制不饱和脂肪酸合成，同时刺激饱和脂肪酸合成。使用脂肪酸合成缺陷的突变菌株，研究了浅蓝菌素对β-酮酰-[酰基载体蛋白]合成酶I和II的影响。我们的结果表明，β-酮酰-[酰基载体蛋白]合成酶I比β-酮酰-[酰基载体蛋白]合成酶II对浅蓝菌素的抑制更敏感。
