Appl Environ Microbiol. 1996 Apr;62(4):1383-90. doi: 10.1128/aem.62.4.1383-1390.1996.
The Gotland Deep, an anoxic basin, was investigated for its heterotrophic microflora as a station representative of the central Baltic Sea and as an example of a brackish water environment. One hundred twenty-three bacterial strains were isolated along the water column by use of four different cultivation procedures. High-resolution electrophoresis of the low-molecular-weight (LMW) RNA (5S rRNA and tRNA) was used for analysis of the taxonomic position of the strains. The banding pattern of the LMW RNA generated by the electrophoresis allowed a taxonomic grouping at the species level of the 123 strains into 24 different genotypes. This grouping was confirmed by use of long-range gels with a substantially better resolution than that of standard gels; i.e., about 60% more tRNA bands were obtained on the long-range gels, and the distance between the bands was increased by about two-thirds. The majority of the strains (76%) could be identified to the species level by comparison with LMW RNA profiles from reference strains stored in an electronic database. Eighty-seven percent of the strains could be assigned to the families Vibrionaceae, Enterobacteriaceae, and Pseudomonadaceae (rRNA group I). The most abundant species among the isolates were Shewanella putrefaciens (48%) and a new Pseudomonas species (24%). The remaining fraction of 28% of the isolates was split into 22 other genotypes. Thirteen of these genotypes were represented by single isolates. This study demonstrates the utility of LMW RNA profiling for a rapid assessment of genotypic diversity of heterotrophic isolates from natural environments.
哥特兰深海是一个缺氧盆地，作为波罗的海中部的一个站位代表和一个半咸水环境的范例，对其异养微生物群落进行了调查。通过使用四种不同的培养程序，沿水柱分离出了 123 株细菌。采用低分子量（LMW）RNA（5S rRNA 和 tRNA）的高分辨率电泳分析了菌株的分类地位。电泳生成的 LMW RNA 的带型允许将 123 株菌分为 24 个不同的基因型，进行种水平的分类。通过使用长程凝胶进一步证实了这种分组，长程凝胶的分辨率明显高于标准凝胶；即，在长程凝胶上获得了约 60%更多的 tRNA 带，并且带之间的距离增加了约三分之二。通过与存储在电子数据库中的参考菌株的 LMW RNA 图谱进行比较，可将大多数菌株（76%）鉴定到种水平。将 87%的菌株可分配到弧菌科、肠杆菌科和假单胞菌科（rRNA 组 I）。分离株中最丰富的物种是腐败希瓦氏菌（48%）和一种新的假单胞菌（24%）。其余 28%的分离株分为 22 个其他基因型。其中 13 个基因型由单个分离株代表。本研究表明，LMW RNA 分析可用于快速评估来自自然环境的异养分离物的基因型多样性。
