ABSTRACT
Many of the current methods for enzyme purification and immobilization suffer from several drawbacks, such as requiring tedious multistep procedures or long preparation, and being environmentally unfriendly, due to the chemicals and conditions involved. Thus, a simple technique for direct purification and immobilization of target enzymes from cell lysates was proposed. The elastin-like polypeptides (ELPs)-SpyCatcher chimera could mediate the formation of silica carriers within seconds and the target enzymes were then covalently immobilized on silica carriers via SpyCatcher/SpyTag spontaneous reaction. These tailor-made carriers were easily prepared, with precisely controlled morphology and size, as well as none-consuming surface modification needed, which could specifically immobilize the SpyTag-fused target enzymes from the cell lysate without pre-purification.
ABSTRACT
PAH-degrading microbial consortium and its pyrene-degrading plasmids were enriched from the sediment samples of Huian mangroves. The consortium YL showed degrading abilities of 92.1%, 87.6%, 92.3%, and 95.8% for pyrene, fluoranthene, phenanthrene, and fluoene at 50 mg l(-1) after 21 days incubation, respectively. The dynamics of pH changes in the cultures was consistent with that of PAH concentration change. Bacillus cereus Py5 and Bacillus megaterium Py6 were isolated from the consortium and observed consuming 65.8% and 33.7% of pyrene (50 mg l(-1)) within three weeks, respectively. The enriched Escherichia coli DH5alpha cells containing the plasmids of YL were demonstrated to degrade 85.7% of the original pyrene concentration at the 21st day.
