Moré M I, Finger L D, Stryker J L, Fuqua C, Eberhard A, Winans S C
Section of Microbiology, Cornell University, Ithaca, New York 14853, USA.
Science. 1996 Jun 14;272(5268):1655-8. doi: 10.1126/science.272.5268.1655.
Many bacteria, including several pathogens of plants and humans, use a pheromone called an autoinducer to regulate gene expression in a cell density-dependent manner. Agrobacterium autoinducer [AAI, N-(3-oxo-octanoyl)-L-homoserine lactone] of A. tumefaciens is synthesized by the Tral protein, which is encoded by the tumor-inducing plasmid. Purified hexahistidinyl-Tral (H6-Tral) used S-adenosylmethionine to make the homoserine lactone moiety of AAI, but did not use related compounds. H6-Tral used 3-oxo-octanoyl-acyl carrier protein to make the 3-oxo-octanoyl moiety of AAI, but did not use 3-oxo-octanoyl-coenzyme A. These results demonstrate the enzymatic synthesis of an autoinducer through the use of purified substrates.
许多细菌，包括几种植物和人类病原体，都使用一种名为自诱导物的信息素以细胞密度依赖的方式调节基因表达。根癌农杆菌的根癌农杆菌自诱导物[AAI，N-(3-氧代辛酰基)-L-高丝氨酸内酯]由Tral蛋白合成，该蛋白由致瘤质粒编码。纯化的六组氨酸-Tral（H6-Tral）利用S-腺苷甲硫氨酸生成AAI的高丝氨酸内酯部分，但不使用相关化合物。H6-Tral利用3-氧代辛酰基-酰基载体蛋白生成AAI的3-氧代辛酰基部分，但不使用3-氧代辛酰基辅酶A。这些结果证明了通过使用纯化的底物进行自诱导物的酶促合成。
