Abstract: This work aims to screen new type of strain producing novel heparinase,and to prepare novel heparinase and test its ability of degrading heparin. The bacteria in soil were cultured using the directional enrichment method,and strains producing heparinase were isolated. Microbial fermentation and purification technology were adopted to prepare novel heparinase,and to study the physical and chemical properties and the cleavage site of novel heparinase. Then,the heparinase were applied to degrade heparin,and the obtained low molecular weight heparins（LMWHs）were characterized. A new heparinase-producing strain belonging to the genus of Sphingo spiritivorum was isolated. The crude enzyme after fermentation was purified with multi-step column chromatography and novel heparinase SShepI and SShepII were obtained,with which two kinds of novel low molecular weight heparins were generated by the degradation of heparin. Conclusively,novel heparinase SShepI and SShepII isolated and purified from a strain of S. spiritivorum are adopted to degrade heparin for preparing low molecular weight heparins,which are expected to be developed into LMWH drugs with better anticoagulant effect or new clinical function.

Key words: Sphingo spiritivorum, heparinase, preparation, characterization