Abstract: To explore the role of pectinase degrading cell wall and further improve the information of cellulose-degrading enzymes in Fusarium sp. Q7-31T,the pectinase from Fusarium sp. Q7-31T was isolated,purified,and identified,followed by bioinformatics analyses. Q7-31T was cultured by induction and fermentation with 0.8% peptone as nitrogen source and 0.5% oat straw as carbon source. Then the pectinase PGL1 was purified from crude enzyme liquid using Sephacry S-100 chromatography and DEAE-sepharose ion-exchange column chromatography. Further,its enzymatic properties were analyzed and MADIL-TOF-TOF identification was conducted. Finally,its structure was analyzed and the function was predicted by bioinformatics. The molecular weight and isoelectric point（pI）of PGL1 was 36.21 kD and 8.13,respectively. PGL1 had optimal activity at 50℃ and p H 8.0,was highly stable at 20℃ to 50℃ and pH 8.0 to 10.0,and was inhibited by Na⁺,K⁺,Mg²⁺,Zn²⁺,Ca²⁺,and Fe²⁺. MADIL-TOF-TOF identification showed that the PGL1 was a new PL-1 family pectinase. The secondary structure prediction suggested that random coil and extended strand were major secondary components（37.96% and 31.17% respectively）. PGL1 had two hydrophilic ends and a hydrophobic middle part. Its phosphorylation sites were 13（Ser：9;Thr：3;Tyr：1）. There were 2 potential N-glycosylation sites in PGL1. The prediction of transmembrane domain revealed that PGL1 was a secretory enzyme. The functional domain prediction of PGL1 showed the role of its degrading plant cell wall. Conclusively,a new PL-1 family pectinase PGL1 was isolated and purified from Fusarium sp. Q7-31T and analyzed by bioinformatics.

Key words: Fusarium sp., pectinase, isolation and purification, enzymatic properties, bioinformatics analysis