Benlloch S., Acinas S.G., Antón J., López-López A., Luz S.P., Rodríguez-Valera F.
División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, 03550 San Juan, Alicante, Spain.
Microb Ecol. 2001 Jan;41(1):12-19. doi: 10.1007/s002480000069.
The culturable haloarchaeal diversity in a crystallizer pond from a solar saltern has been analyzed and compared with the biodiversity directly retrieved by analysis of rRNA genes amplified from the environment. Two different sets of culture conditions have been assayed: solid medium with yeast extract as carbon source and liquid media with either yeast extract or a mixture of fishmeal, Spirulina sp., and Artemia salina. Seventeen colonies grown on plates with yeast extract incubated at 30 degrees C were analyzed by 16S rDNA partial sequencing. Sixteen were closely related to haloarchaea of the genus Halorubrum; 13 of them to Halorubrum coriense, a haloarchaeon isolated from a solar saltern pond in Australia, which had not been previously isolated from the pond analyzed in this study; and one to Haloarcula marismortui. Liquid cultures were analyzed by ribosomal internal spacer analysis (RISA) and partial sequencing of the 16SrRNA genes. A total of 18 sequences were analyzed, 15 corresponding to RISA bands obtained from cultures, and 3 from the environmental sample used as inoculum. Thirteen sequences obtained from cultures were related to several Halorubrum species, and 2 to Haloarcula. One of the clones obtained directly from the environmental sample was distantly related to a Natronobacterium, whereas two were related to SPhT, the phylotype most frequently retrieved from this environment by culture independent techniques. Our results show an extremely low diversity for the haloarchaea retrieved by cultivation even when modifications to the standard technique are introduced.
对一个太阳能盐场结晶池中可培养的嗜盐古菌多样性进行了分析，并与通过分析从环境中扩增的rRNA基因直接获得的生物多样性进行了比较。测定了两组不同的培养条件：以酵母提取物为碳源的固体培养基，以及以酵母提取物或鱼粉、螺旋藻和卤虫混合物为碳源的液体培养基。对在30℃下用酵母提取物培养的平板上生长的17个菌落进行了16S rDNA部分测序分析。其中16个与嗜盐红菌属的嗜盐古菌密切相关；其中13个与从澳大利亚一个太阳能盐场池塘分离出的嗜盐红菌密切相关，该嗜盐古菌此前未从本研究分析的池塘中分离出来；1个与死海嗜盐嗜碱菌密切相关。通过核糖体内部间隔区分析（RISA）和16SrRNA基因部分测序对液体培养物进行了分析。共分析了18个序列，其中15个对应于从培养物中获得的RISA条带，3个来自用作接种物的环境样品。从培养物中获得的13个序列与几种嗜盐红菌属物种相关，2个与嗜盐嗜碱菌属相关。直接从环境样品中获得的一个克隆与嗜盐碱杆菌属关系较远，而两个与SPhT相关，SPhT是通过非培养技术从该环境中最常检索到的系统发育型。我们的结果表明，即使对标准技术进行了改进，通过培养获得的嗜盐古菌的多样性仍然极低。
