CAJ | 학술논문

S-层(S-layer)普遍存在于古菌、G+、G-菌中,由S-层蛋白所构成细菌S-层结构的生物体中,其功能引起了科学家的广泛关注,但目前S-层的功能大都处于推测阶段.究其原因,是因为外源S-层基因可以造成宿主大肠杆菌的致死效应.本研究将一株苏云金芽胞杆菌的两个S-层蛋白基因(GenBank登录号为AJ012290和AY460125)的3'端序列在大肠杆菌BL21(DE3)中成功进行异源表达,在0.8 mmol/L IPTG诱导培养6 h时,菌体中包涵体表达量达到最高;并对表达蛋白进行了初步分离纯化,以期为后期利用该纯化蛋白进行抗血清制备,进而对该菌的S-层蛋白在宿主菌中的定位、功能分析打下基础.
S-층(S-layer)보편존재우고균、G+、G-균중,유S-층단백소구성세균S-층결구적생물체중,기공능인기료과학가적엄범관주,단목전S-층적공능대도처우추측계단.구기원인,시인위외원S-층기인가이조성숙주대장간균적치사효응.본연구장일주소운금아포간균적량개S-층단백기인(GenBank등록호위AJ012290화AY460125)적3'단서렬재대장간균BL21(DE3)중성공진행이원표체,재0.8 mmol/L IPTG유도배양6 h시,균체중포함체표체량체도최고;병대표체단백진행료초보분리순화,이기위후기이용해순화단백진행항혈청제비,진이대해균적S-층단백재숙주균중적정위、공능분석타하기출.
Surface layer, S-layer, is a part of the cell envelope commonly found in bacteria (both Gram-positive bac-teria and Gram-negative bacteria), as well as among archaea. The functions of S-layer, attracting wide attention from scientists, are not clearly studied yet due to the lethal effect of exogenous S-layer protein gene to Escherichia coli host strains. Most of the functions we knew currently are deduced and have not been certified. In this study, the 3' end sequence from two S-layer protein gene of a Bacillus thuringiensis strain (GenBank accession number AJ012290 and AY460125) have been successfully expressed in Escherichia coli BL21 (DE3). The expression of the inclusion body in the mycelium reached the highest level after culturing for 6 h in 0.8 mmol/L IPTG. The expressed proteins were preliminary separated and purified, in order to lay a foundation for the preparation of antiserum, and for the localiza-tion and function analysis of S-layer protein in the host.