Heterogeneous Expression Of Xylanase Gene From Fusarium Sp. Q7-31 And The Characteristics Of Expressed GST-Xylw8

Fusarium is one of the most important plant pathogens. In addition to its study of its pathogenicity, there are also have some reported about the sourse of cellulase and hemicellulase. Fusarium sp. plays important roles in fermented production of bio-ethanol. In the study, directly transform lignocellulose substance to ethanol, Neurospora crassa and Fusarium oxysporum f. have become two typical fungis.In this study, Fusarium sp. Q7-31 is the research subject. The xlanase gene of xynw8 which was acquired sequence by our laboratory was cloned from cDNA of Fusarium sp. Q7-31. Xynw8 encodes a xylanase with a calculated molecular weight of 25.7 KD. The theoretical pI is 6.9. The protein has a signal peptide with the sequence MVSFKFLLVAASAITGALA. The xylanase Xylw8 was belonging to G11 xylanase family.Construct the recombinant expression vector of pGEX5x-1-xynw8. The xylanase gene xynw8 was expressed in Ecoli.BL21 (DE3). The production of recombine xylanase was identified by SDS-PAGE and Western blot. Recombine xylanase was purified by affinity chromatography. The characteristics of expressed Xylw8 were studied.The xylanase gene xynw8 was expressed in Ecoli with a molecular weight of 52KD in a fusion protein form. The result of substrate specificity indicate that the enzyme have an activity in degradation of xylan, without activity in degradation of CMC and Starch both. The optimum pH is 6.0 and the optimum temperature is 40℃. Mix the recombine xylanase and wild crud enzymes, the recombine xylanase can boost the xylanase activity of the culture medium of Fusarium sp. Q7-31.