The Research Of The Purification Of RsmI And BACE1and The Crystal Structures

RsmI is a methyltransferase of E. coli, which is responsible for catalysis the2’-O-methylation at C1402of E.coli16S rRNA which interacts with the P-site codon of themRNA derectly. So far,the study about RsmI is very rarely. Here we report the process of theclone, expression, and purification of RsmI and RsmI12-258. And we have got the diffraction dataof the compound of RsmI12-258and SAM at the SSRF which between2to3., then weresolved the three dimensional space structure of the compound of RsmI12-258and SAM.In humans, amyloid plaques is the main composed of theβ-amyloid (Aβ), which hasneurovirulence and could cause the nerve cell death. The formation and accumulation ofamyloid plaques is an significant pathogenesis leading to Alzheimer’s disease. β-secretase(BACE1) is a novel transmembrane aspartic protease which limit the produce of Aβ. Therefore,by inhibiting the activity of BACE1could inhibited β-amyloid production, thereby inhibiting orslowing Alzheimer’s. In this experiment, we use the E. coli as the host to expression BACE1, butBACE1in E. coli express in inclusion bodies. So we used a generalized protocol whichdeveloped to solubilize, refold, and purify these BACE1variants. We have got the high activeand homogeneous and stable BACE1. But we have not got the diffraction data which was ableto resolve the structure of BACE1yet, and further optimization experiments in progress.This research in strict accordance with the process of X-ray cyrstallography, with E.colias the host to express, purify, and crystallize the RsmI and BACE1. And we got the crystalstructure of the compound of RsmI and SAM through X-ray.