Recombinant Expression of the Monomeric B27 Lys Destripeptide Insulin Precursor( MIP) in Escherichia coli

Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic. But the yield of monomeric B27 Lys destripeptide insulin is limited, because monomeric B27 Lys destripeptide insulin precursor( MIP) was easily to form inclusion body,when MIP is expressed in E. coli. The precursor,MIP,is not only fused to an N-terminal HIS-small ubiquitin-related modifier( SUMO) tag,but also added five Arginine( 5 R) at the C-terminal,which can improve the solubility of the fusion protein. By this way,the yield of fusion protein has been up to 1. 45 mg/L cell culture.This work set up the foundation for the clinical application of B27 Lys destripeptide insulin.     

Small Amplicons Mutation Library for Vaccine Screening by Error-Prone Polymerase Chain Reaction

Library construction is a common method used to screen target genes in molecular biology. Most library constructions are not suitable for a small DNA library(<100 base pair(bp)) and low RNA library output. To maximize the library’s complexity, error-prone polymerase chain reaction(PCR) was used to increase the base mutation rate. After introducing the DNA fragments into the competent cell, the library complexity could reach 10⁹. Library mutation rate increased exponentially with th...