Recombinant Expression And Characterization Of Fenneropenaeus Chinensis Cathepsin L And Lysozyme

The aquaculture of Chinese shrimp has rapidly grown to a major economic activity in our country. Shrimp can provide a high quality food product and is very welcome. However, the rapidly expanding fleshy prawn industry has caused many problems since 1990's. Diseases have emerged as a major constraint to the sustainable growth of shrimp aquaculture, especially the infection of virus, causing lots of losing. Many studies have been done, but the immunology mechanism of shrimp is not well understood. In order to cure the diseases, the immunology mechanism of shrimp must be well understood.Cathepsin L is the most abundant cysteine protease with only endopeptidase activity. The cathepsin L is responsible for intracellular protein degradation, and it is also involved in many other important physiological roles such as antigen presentation, tumor invasion and metastasis, bone resorption and apoptosis. Crustacean cathepsin L is not well understood, which would be further studied.Lysozyme is widely distributed among eukaryotes and prokaryotes. It catalyzes the hydrolysis of bacterial cell walls and acts as a nonspecific innate immunity molecule against the invasion of bacterial pathogens.Our laboratory cloned cathepsin L (FCL) and lysozyme (FLYZ) genes from Chinese shrimp (Fenneropenaeus chinensis). We have successfully expressed the two genes in E. coli and characterized the recombinant proteins. Hereunder are results of my research:1. FCL was subcloned into the plasmid pET-30a(+) and the recombinant protein FCL was expressed in E.coliBL21(DE3). Results show that the FCL was highly expressed in E.coliBL21(DE3) with IPTG induction in percentage of 40% of total cell proteins. FCL was purified by affinity chromatograph. and purified yield reached 111.67...