Vahed Sepideh Zununi, Forouhandeh Haleh, Hassanzadeh Salar, Klenk Hans-Peter, Hejazi Mohammad Amin, Hejazi Mohammad Saeid
Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
Mikrobiologiia. 2011 Nov-Dec;80(6):826-33.
Urmia Lake is one of the most permanent hypersaline lakes in the world which is threatened by hypersalinity and serious dryness. In spite of its importance no paper has been published regarding bacterial community of this lake. Accordingly, the present study aimed to investigate the halophilic bacteria in the aforementioned lake. In so doing, thirty seven strains were isolated on six different culture media. The isolated strains were characterized using phenotypic and genotypic methods. Growth of the strains occurred at 2535 degrees C, pH 6-9 and 7 to 20% (w/v) NaCl indicating that most of the isolates were moderately halophiles. Catalase, oxidase and urease activities were found to be positive for the majority of the isolates. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolated bacteria belonged to two major taxa: Gammaproteobacteria (92%, including Salicola [46%], Pseudomonas [13.5%], Marinobacter [ 11%], Idiomarina [11%], and Halomonas [8%]) and Firmicutes (8%, including Bacillus [5%] and Halobacillus [3%]). In addition, a novel bacterium whose 16S rRNA gene sequence showed almost 98% sequence identity with the taxonomically troubled DSM 3050T, Halovibrio denitrificans HGD 3T and Halospina denitrificans HGD 1-3T, each, was isolated. 16S rRNA gene similarity levels along with phenotypic characteristics suggest that some of the isolated strains could be regarded as potential type strain for novel species, on which further studies are recommended.
乌尔米耶湖是世界上最持久的高盐湖之一，正受到高盐度和严重干旱的威胁。尽管它很重要，但关于该湖细菌群落的研究尚未见报道。因此，本研究旨在调查上述湖泊中的嗜盐细菌。为此，在六种不同的培养基上分离出了37株菌株。采用表型和基因型方法对分离出的菌株进行了鉴定。菌株在25-35℃、pH值6-9和7%-20%（w/v）NaCl条件下生长，表明大多数分离株为中度嗜盐菌。大多数分离株的过氧化氢酶、氧化酶和脲酶活性呈阳性。基于16S rRNA基因序列的系统发育分析表明，分离出的细菌属于两个主要类群：γ-变形菌纲（92%，包括盐栖菌属[46%]、假单胞菌属[13.5%]、海杆菌属[11%]、特立独行菌属[11%]和嗜盐单胞菌属[8%]）和厚壁菌门（8%，包括芽孢杆菌属[5%]和嗜盐芽孢杆菌属[3%]）。此外，还分离出一种新细菌，其16S rRNA基因序列与分类存在争议的DSM 3050T、反硝化嗜盐弧菌HGD 3T和反硝化嗜盐刺菌HGD 1-3T的序列相似性均接近98%。16S rRNA基因相似性水平和表型特征表明，一些分离株可能被视为新物种的潜在模式菌株，建议进一步研究。
