Isolation,Identification And Analysis Of The Whole Gene Sequence Of Staphylococcus Aureus In The Respiratory Tract Of Goats In Guangxi

Pathogenic Staphylococcus aureus is very harmful to animal health.In this study,we isolated and identified S.aureus causing respiratory diseases in Guangxi region,and established a highly sensitive and highly specific fluorescence quantitative PCR method for the detection of S.aureus.The whole genome of SA GX2019 strain was sequenced and the biological information was mined,which provided a basis for further understanding of the bacteria and prevention and treatment of respiratory diseases caused by the bacteria in production.(1)About 300 samples of goat nose swabs with respiratory symptoms such as runny nose and cough from goat farms in Guangxi were collected and tested for pathogenic bacteria.The purified S.aureus strain was isolated from 20 goat nose swabs from Wuzhou,and the S.aureus strain isolated from sample No.8 was named SA GX2019.(2)Primers were designed according to the published nuc gene sequence of S.aureus on Gen Bank,and a real-time fluorescence quantitative PCR method was established.The determination coefficient R2 of the standard curve was 0.9798,the Slope was-2.9858,the amplification efficiency E was 116.2%,and the minimum sample detection concentration was 1×101 CFU/m L.The experimental results showed that the method has high sensitivity,high specificity and good repeatability.By comparing the established fluorescence quantitative PCR detection method with the common PCR detection method.The results showed that the detection rate of fluorescence quantitative PCR method was 13.33% higher than that of ordinary PCR method,which was beneficial to clinical detection.The method of real-time fluorescence quantitative PCR established in this experiment can accurately identify S.aureus.The research results can provide technical support for the diagnosis,prevention and control of respiratory tract S.aureus infection.(3)The sequencing results of the whole genome of SA GX2019 strain showed that the full length of its genome was 2773319 bp,and the GC content was 33%.2686 genes were predicted,accounting for 84.08%.The whole genome was predicted by CRISPR and bioinformatics analysis including COG,GO and KEGG annotation.It was predicted that there were 28 species of t RNAs,56 t RNAs,and 3 species of r RNAs,7 r RNAs.This study explored the key biological information of the pathogenic strain from the perspective of bioinformatics,and laid a foundation for the further study on the diagnosis and drug resistance genes of the pathogen in Guangxi.