柑橘黄龙病病菌FabD蛋白酶的基因克隆与表达

Cloning and Expression Analysis of Malonyl CoA:ACP Transacylase( FabD) from Candidatus Liberibacter Asiaticus

柑橘黄龙病病菌(Candidatus Liberibacter)是黄龙病的致病菌.脂肪酸是细胞生物膜的重要组成成分,脂肪酸的生物合成对于病原细菌的生存至关重要.干扰病原菌生物膜的合成将抑制病原菌的生长和繁殖.本研究克隆了柑橘黄龙病病菌脂肪酸合成通路中的关键蛋白酶-丙二酸单酰CoA:ACP转酰基酶(FabD,Malonyl CoA:ACP transacylase)基因,构建了该基因在大肠杆菌系统中的表达载体p ET28a-FabD,成功实现了该基因在大肠杆菌系统中的重组表达.结果表明,该蛋白酶在大肠杆菌内为包涵体表达,复性后最终制备得到浓度为0.38 mg/m L的可溶性FabD蛋白酶.

The pathogen of Citrus Huanglongbing is Candidatus Liberibacte. The fatty acid biosynthesis in pathogenic microorganisms is essential for cell viability. The enzymes involved in the pathway of fatty acid synthase （FAS） have been regarded as targets for antibacterial drug discovery. In this study, one of the fatty acid sythase FabD from Candidatus Liberibacter asiaticus has been cloned, and the recombinant plasmid of pET28a-FabD was constructed. Finally, the soluble FabD protease of a concentration of 0. 38 mg/ml, has been obtained successfully by the methods of inclusion body purification and protein refolding.