Strain with Thermo-Stable Lysine Aminopeptidase：Isolation，Identification and Gene Cloning

Abstract:

The strain isolated from soil, producing an aminopeptidase, was identified by physiological, biochemical and molecular biological methods, named Pseudomonas aeruginosa NJ-814. Based on this enzyme which have been investigated a thermo-stable Lysine Aminopeptidase, the kap gene was cloned from the genomic DNA of Pseudomonas aeruginosa NJ-814 by PCR. The expression vector pET-28a-kap was constructed to partly express fusion protein in E. coli BL21(DE3). The kap gene contains 1 500 nucleotides coding 499 amino acids. The deduced amino acids of kap had a high similarities with Streptomyces exfoliates and Saccharopolyspora erythraea. The physical and chemical properties was analyzed with the biological informatics method and the kap gene was successfully expressed in the E. coli BL21(DE3), which lay the foundation for further research of the thermo-stable mechanisms and functional characterization of the aminopeptidase.