Construction Of Haemophilus Parasuis Gene Expression Library And Mining Of New Gene

Haemophilus parasuis is a non-motile, small pleomorphic Gram-negative rod of thefamily Pasteurellaceae. This species is the causative agent of Glasser's disease, which isa characteristic of porcine fibrinous polyserositis, polyarthritis and meningitis. Thisdisease is often associated to important economic losses in the swine industryworld-wide due to high morbidity and mortality rates. So far, little is known about thestudies of haemophilus parasuis, especially in the molecular level, and the number ofgene reported now is no more than 20. Haemophilus parasuis serovar 5, a dominantstrain which is prevalent in China serves as research target in this work. After thecomplete genome extraction of the strain was performed, the genomic DNA was partiallydigested by restriction enzyme Sau3Aâ… , the DNA fragments from 1 to 5Kb was clonedinto prokaryote expression vector pET-28a-c, and transformed host bacteria. The resultsshowed that we succeeded in constructing the gene expression library of haemophilusparasuis serovar 5, which is fundamental for the study of advanced gene screening. Inaddition, primer design was performed based on haemophilus influenzae in this study.In addition, PCR was performed by using genomic DNA of haemophilus parasuisserovar 5 as the template. The results demonstrated that we obtained two neo-gene:23SrRNA gene(conserved gene belonging to the large-subunit of ribosome) and adenylatecyclase gene(encodes adenylate cyclase and participates in converting adenyl nucleosidetriphosphate to cyclic adenosine3',5'-monophosphate). Furthermore, the phylogeneticanalyses between the species was performed, and neighbor-joining tree was constructedbased on comparison of 23S rRNA gene sequences, so it was illuminated betweenHaemophilus parasuis and other species in molecular evolution relationship.