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In recent years,xylanase has become a widely used enzyme in feed industry because of its effective degradation of arabinoxylanase and the elimination of anti-nutritional effect of arabinoxylanase.A strain TL01 of heat-resistant xylanase was isolated and purified from the laboratory and it was identified as Thermomyces Lanuginosus through morphology,physiological and biochemical experiments and ITS sequence analysis(Fig.1).Fungal xylanase has attracted much attention because of its stabilization and high degradation efficiency.The xylanase gene(xynA)was cloned and expressed in Escherichia coli.The xynA gene,encoding the xylanase from Thermomyces Lanuginosus,the open reading frame(ORF)was 678 base pairs long and encoded a polypeptie of 225 amino acids with a calculated molecular mass of 24.4 KDa.Prokaryotic expression results showed efficient expression of pET-xynA protein could be realized after induced for 4 h at 30℃ with 100 mmol/L IPTG in E coli Rosetta(Fig.2).Solubility analysis showed the protein mainly existed in the inclusion bodies.The spheroidin was purified by His-Tagged Protein Purification Kit(inciusion body protein).The research results lay a solid foundation for the application of high yield engineering bacteria in fermentation industry.