Expression of lipase I gene from Geotrichum candidum ch-3 in Escherichia coli

A cold-adapted lipase-producing strain Geotrichum candidum ch-3 was isolated from frozen soil containing oil and fat.The optimal temperature of the lipase in the culture supernatant was 35 ℃.It retained 66 % activity at 0 ℃.Lipase I gene lip1 from G.candidum ch-3 was amplified by PCR and inserted into pET-22b(+) to generate recombinant pET-lip1.pET-lip1 was transformed into E.coli BL21(DE3).The Mr of the expression product was 5.8×104 by SDS-PAGE.The lipase activity was 2.73 U/mL,which indicated the cloned DNA fragment encoded a lipase.Lipase gene lip1 of G.candidum ch-3 was efficiently expressed in E.coli.