新疆罗布泊地区嗜盐细菌的分离及其嗜盐特性  

Isolation halophilic bacteria from Lop Nur region and their growth of selectivity to positive ions

作　　者：韩剑[1] 罗明[1] 蒋平安[2] 武红旗[2] 

机构地区：[1]新疆农业大学农学院,新疆乌鲁木齐830052 [2]新疆农业大学资源和环境学院,新疆乌鲁木齐830052

出　　处：《干旱区地理》2008年第6期878-884,共7页Arid Land Geography

基　　金：国家自然科学基金(40671080);新疆特殊环境微生物重点实验室开放项目(XJYS0203-2006-03)资助

摘　　要：从罗布泊“大耳朵”地区盐壳中分离获得108株嗜（耐）盐细菌。试验比较了不同培养基的分离效果，测定了嗜（耐）盐细菌对NaCl的耐受性，生长pH范围及对Na^＋、K^＋、Mg^2＋、Ca^2＋的选择性。结果表明，添加罗布泊盐壳浸提物的CM改良培养基更有利于嗜（耐）盐细菌的富集培养和分离。罗布泊嗜盐细菌中以革兰氏阴性菌、杆菌为主，大多具有产生色素的特性。大多菌株的pH生长范围是6．0～10．0，最适生长pH值是7．0—8．0。根据生长的NaCl浓度，将分离菌株划分为中等嗜盐细菌、极端嗜盐细菌和耐盐细菌，所占比例分别为24％，27％，49％。嗜（耐）盐细菌的分布与组成类型与分离地点的含盐量有一定的相关性。多数嗜盐细菌对Na^＋、K^＋、Mg^2＋有广泛的适应性，生长所需的Na^＋可以被一定浓度的K^＋、Mg^2＋替代，但缺乏对Ca^2＋的适应性。多数耐盐细菌对Na^＋、K^＋、Mg^2＋、Ca^2＋的选择性不强。少数嗜（耐）盐细菌对Na^＋、K^＋、Mg^2＋、Ca^2＋具有专一的选择适应性。One hundred and eight halophihc bacteria stains were isolated from the salt crust and saline soils from the ＂large-ear＂ part of Lop Nur region in Xinjiang. Effects of different medias on halophile isolation, NaCl tolerance concentration, growth pH range and selectivity to Na^＋, K^＋, Mg^2＋ , Ca^2＋ of the isolates were studied. The results indicated that the media which added in the extract of the salt crust was proved to be more effective on the enrichment culture and isolation of the halophile. Majority of the halophilic bacteria are gram-negative, have the characteristic to excrete the pigment. The growth pH range was from 6.0 to 10.0, and the optimum pH was 7.0 - 8.0. According to growth NaCl concentration, the bacteria were classified as moderate halophile, extreme halophile and halotolerant, the proportions were 24%, 27%, 49%, respectively. The distribution and composition of halophile had some relations to the isolation sites. Most of the halophile have extensive adaptability to different Na^＋ , K ^＋ , Mg^2＋ , and Na^＋ can be substituted by K^＋ , Mg^2＋, but could not adapt to Ca^2＋. It was also showed that the growth of most of the halotolerant had not much more selectivity to different concentration of Na^＋ , K ^＋ , Mg^2＋ , Ca^2＋. For few of the halophile and halotolerant strains, their growth only depended on one of the positive ions respectively, such as Na^＋ , K^＋ ,Mg^2＋ and Ca^2＋. So it is presumed that only Kaliumphilic or Magnesiumphilic halophilic bacteria maybe exist in high salt environments. The distribution of halophilic bacteria also had some relations to the isolation sites. The results showed that the number of halotolerant bacteria and halophilic bacteria changed in different sampiing sites. The amount of extreme halophiles was greater than that of halotolerant bacteria and moderately halophilic bacteria in high salt soil.

关 键 词：罗布泊 嗜盐细菌 分离 阳离子 选择性 

分 类 号：Q93[生物学—微生物学]