Balkwill D L, Reeves R H, Drake G R, Reeves J Y, Crocker F H, King M B, Boone D R
Department of Biological Science, Florida State University, Tallahassee 32306-3043, USA.
FEMS Microbiol Rev. 1997 Jul;20(3-4):201-16. doi: 10.1111/j.1574-6976.1997.tb00309.x.
The Subsurface Microbial Culture Collection (SMCC) was established by the U.S. Dept. of Energy (DOE) and contains nearly 10,000 strains of microorganisms (mostly bacteria) isolated from terrestrial subsurface environments. Selected groups of bacterial isolates from three sample sites situated above geochemically and hydrologically different subsurface environments have been characterized by phylogenetic analysis of 16S ribosomal RNA (rRNA) gene nucleotide sequences. Among these isolates were members of six major phylogenetic groups of bacteria: the high-G+C and low-G+C Gram-positive bacteria; the alpha-, beta-, and gamma-subdivisions of the Proteobacteria; and the Flexibacter/Cytophaga/Bacteroides group. A small number of the SMCC strains may be members of new bacterial genera, but most of them could be placed with reasonable confidence into more than 35 previously described genera. The majority of the Gram-positive isolates were species of Arthrobacter, Bacillus, or Streptococcus, whereas Acinetobacter, Comamonas, Pseudomonas, Sphingomonas, and Variovorax were among the most frequently encountered Gram-negative genera. A high proportion of the strains were placed in fewer than 10 genera, implying that there is substantial duplication within the SMCC at the genus level. When groups of isolates assigned to Acinetobacter, Arthrobacter, or Sphingomonas were analyzed in more detail, however, it was found that each group consisted of subgroups of strains that probably differed at the species level. Restriction endonuclease analysis (applied to the strains from one sample site) indicated that additional diversity was present at the strain level. Most of the SMCC isolates assigned to some genera (e.g., Acinetobacter) were very closely related to previously described species in those genera, but most of the isolates assigned to other genera (e.g., Arthrobacter and Sphingomonas) appeared (or were shown) to be new species, thereby indicating that a reasonable amount of novelty is present within the SMCC at the species level.
地下微生物培养物保藏中心（SMCC）由美国能源部（DOE）设立，保存了近10000株从陆地地下环境中分离出的微生物菌株（主要是细菌）。对来自三个位于地球化学和水文条件不同的地下环境之上的采样点的部分细菌分离株，通过16S核糖体RNA（rRNA）基因核苷酸序列的系统发育分析进行了表征。这些分离株中包括细菌的六个主要系统发育组的成员：高G+C和低G+C革兰氏阳性菌；变形菌门的α-、β-和γ-亚纲；以及柔杆菌/噬纤维菌/拟杆菌群。SMCC中的少数菌株可能是新细菌属的成员，但其中大多数可以合理地归入35个以上先前描述的属中。大多数革兰氏阳性分离株是节杆菌属、芽孢杆菌属或链球菌属的物种，而不动杆菌属、丛毛单胞菌属、假单胞菌属、鞘氨醇单胞菌属和贪铜菌属是最常见的革兰氏阴性菌属。很大一部分菌株归入不到10个属，这意味着在属水平上SMCC内存在大量重复。然而，当对归入不动杆菌属、节杆菌属或鞘氨醇单胞菌属的分离株组进行更详细分析时，发现每个组都由可能在种水平上存在差异的菌株亚组组成。限制性内切酶分析（应用于来自一个采样点的菌株）表明在菌株水平上还存在其他多样性。归入某些属（如不动杆菌属）的大多数SMCC分离株与这些属中先前描述的物种密切相关，但归入其他属（如节杆菌属和鞘氨醇单胞菌属）的大多数分离株似乎（或被证明）是新物种，从而表明在种水平上SMCC内存在一定数量的新物种。
