Rusznyák Anna, Vladár Péter, Szabó Gitta, Márialigeti Károly, Borsodi Andrea K
Department of Microbiology, Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary.
Extremophiles. 2008 Nov;12(6):763-73. doi: 10.1007/s00792-008-0183-5. Epub 2008 Aug 5.
Bacterial diversity of reed (Phragmites australis) periphyton communities of Kelemen-szék and Nagy-Vadas (two Hungarian soda ponds) was investigated using molecular cloning and cultivation-based techniques. The majority of the 80 Kelemen-szék and 72 Nagy-Vadas bacterial isolates proved to be moderately halophilic and alkaliphilic. A great proportion of the isolates showed phosphatase and urease activity, utilized aesculin, citrate and certain biopolymers (e.g., gelatine and tween 80). Partial 16S rDNA sequence analysis of 33 Kelemen-szék and 20 Nagy-Vadas ARDRA group representatives showed Gram-positive (Nesterenkonia, Cellulomonas, Dietzia, Bacillus and Planococcus) dominance at both sampling sites. Species of the genera Acidovorax, Hydrogenophaga (beta-Proteobacteria) and Flavobacterium, Sphingobacterium (Bacteroidetes) were represented only from Kelemen-szék. Altogether 16 isolates showed low sequence similarity with yet described bacteria and may represent novel taxa. Screening of the 16S rRNA gene libraries of 129 Kelemen-szék and 158 Nagy-Vadas clones resulted in 30 and 28 different ARDRA groups, respectively. Sequence analysis revealed a Gram-negative (Rheinheimera, Aquimonas, Cellvibrio, Flavobacterium and Sphingobacterium) dominated phylogenetic diversity. A high number of the clones were affiliated with uncultured bacterial clones described from diverse environmental samples.
利用分子克隆和基于培养的技术，对凯莱门 - 塞克（Kelemen - szék）和纳吉 - 瓦达斯（Nagy - Vadas）（匈牙利的两个盐碱湖）芦苇（Phragmites australis）周丛生物群落的细菌多样性进行了研究。在凯莱门 - 塞克的80株和纳吉 - 瓦达斯的72株细菌分离物中，大多数被证明是中度嗜盐和嗜碱的。很大一部分分离物显示出磷酸酶和脲酶活性，利用七叶苷、柠檬酸盐和某些生物聚合物（如明胶和吐温80）。对33株凯莱门 - 塞克和20株纳吉 - 瓦达斯ARDRA组代表的部分16S rDNA序列分析表明，两个采样点均以革兰氏阳性菌（涅斯捷连科氏菌属、纤维单胞菌属、迪茨氏菌属、芽孢杆菌属和动性球菌属）为主。嗜酸菌属、嗜氢菌属（β - 变形菌纲）以及黄杆菌属、鞘氨醇杆菌属（拟杆菌门）的物种仅在凯莱门 - 塞克被发现。共有16株分离物与已描述细菌的序列相似性较低，可能代表新的分类单元。对129个凯莱门 - 塞克和158个纳吉 - 瓦达斯克隆的16S rRNA基因文库进行筛选，分别得到30个和28个不同的ARDRA组。序列分析显示，系统发育多样性以革兰氏阴性菌（莱茵海默氏菌属、水生单胞菌属、纤维弧菌属、黄杆菌属和鞘氨醇杆菌属）为主。大量克隆与从不同环境样本中描述的未培养细菌克隆相关。
