一株产酯酶中度嗜盐菌的筛选及酶学性质的研究

目的]研究大庆采油厂附近盐碱地产酯酶的中度嗜盐菌菌株的形态和生理生化特点及其所产胞外酯酶的性质.方法]利用平板筛选法分离得到一株产酯酶中度嗜盐菌,对其进行形态、生理生化和分子水平的鉴定,并对其产生的酯酶的部分酶学性质进行研究.结果]初步判断产酯酶的菌株Z01为Gracilibacillus saliphilus strain YIM 91119;对酯酶粗酶液酶学性质的研究结果显示其最适反应温度为45℃,最适反应pH为8.5,酶反应最适NaCl浓度为10％;所产酯酶在50℃以下时稳定性好,对pH的碱耐受性好,对小于15％浓度的盐溶液耐性较好.结论]分离得到了一株产酯酶活性较高的中度嗜盐菌.

Isolation,Characterization, and Enzymology Properties of a Moderately Halophilic Bacterium

Objective] We separated and identified the moderately halophilic bacteria which produce functional enzymes from saline and alkaline soil near Daqing oil production company.Morphological,physiological and biochemical characteristics and the nature of extracellular esterase of the moderately halophilic bacterium were studied.Method] The plate screening method was used by adding enzyme specific substrate into the medium to separate and identify the moderately halophilic bacteria which produce esterase enzymes.Moreover,some properties of esterase were studied.Result] Esterase strains Z-01 was preliminary judged as Gracilibacillus saliphilus strain YIM 91119.Through researching crude enzyme properties and producing enzyme optimization from the moderately halophilic bacterias,tbe optimum reaction conditions were temperature 45 ℃,pH 8.5 and NaCl concentration 5％.The enzyme had good thermal stability below 50 ℃,good pH tolerance and better salt tolerance for less than 15％ concentration of salt solution.Conclusion] The moderately halophilic bacterium with high yield esterase activity was separated and identified.