中文摘要：

Beta-ketoacyl-acyl-carrier-protein synthase II，在细菌的丰满的酸的生合成的重要的酶，是在抗菌剂药设计的一个吸引人的目标。Platensimycin (PTM ) ，由 Streptomyces platensis 生产了，由有选择地指向到 FabF 举办一项强壮的、用途广泛的克积极的抗菌剂活动，但是不从 Streptomyces platensis (spFabF ) 展出抑制到 FabF。为了在生产 PTM 紧张以内学习自我抵抗机制并且提供，为新奇抗菌素的开发提示，解决 spFabF 的结构并且阐明是必要的 spFabF 之间的差别和不对 PTM 抵抗的另外的 FabFs。到这个目的，在宽类型的 spFabF 的表示被没有通过以后，我们基于 spFabF 和它的相应蛋白质的顺序构造了四妄想的 FabFs。一个怪物的水晶结构， js ₂₀₀ 到 spFabF 的 91.2% 顺序身份， FabF 被解决。js ₂₀₀ 有 PTM 固定的 FabF 的 FabF 建议催化地点可能玩的附近的三个环在阻止 PTM 的绑定到 spFabF 给角色调音。结果在自我抵抗机制和指向 FabFs 的新奇抗菌素的基于结构的设计上为进一步的研究提供一个令人鼓舞的基础。

英文摘要：

Beta-ketoacyl-acyl-carrier-protein synthase II, an important enzyme in biosynthesis of bacterial fatty acid, is an attractive target in antibacterial drug design. Platen- simycin （PTM）, produced by Streptomyces platensis, has a strong, broad-spectrum Gram-positive antibacterial activity by selectively targeting to FabF but exhibits no inhibition to the FabF from Streptornyces platensis （spFabF）. To study the self-resistance mechanism within the PTM-pro- ducing strain and provide hint for development of novel antibiotics, it is imperative to solve the structure of spFabF and elucidate the difference between spFabF and other FabFs which are not resistant to PTM. To this end, we constructed four chimeric FabFs based on the sequence of spFabF and its homologous protein after the expression of wide-type spFabF was failed. The crystal structure of one chimera, js200FabF, of 91.2% sequence identity to spFabF, was solved. A structure comparison of js200FabF with a PTM-bound FabF suggested that three loops nearby the catalytic site might play key roles in preventing the binding of PTM to spFabF. The results provide an encouraging basis for further studies on the self-resistance mechanismand structure-based design of novel antibiotics targeting FabFs.