Study on low-temperature lipase of psychrophilic bacterium 2-5-10-1 isolated from deep sea of Southern Ocean

A strain of psychrophilic bacterium,2-5-10-1,which produces low-temperature lipase,is isolated from the deep sea of Prydz Bay in Southern Ocean.The highest lipase secretion of this strain is observed at 5℃ and this temperature is also for optimal growth.Tween 80 and olive oil enhance secretion of lipase.The optimal temperature and pH for lipase activity are 35℃ and 7.5℃ respectively.At 0℃,the lipase still has 37% relative enzyme activity.The lipase shows high thermolability,more than 50% activity lost after incubation at 60℃ for 15 min.EDTA has no effect on lipase activity,indicating the lipase activity is independent of divalent cation.In contrast,the lipase activity is inhibited drastically by Cu²⁺ and Zn²⁺.