Ventosa A, Márquez M C, Garabito M J, Arahal D R
Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, Spain.
Extremophiles. 1998 Aug;2(3):297-304. doi: 10.1007/s007920050072.
Moderately halophilic bacteria are microorganisms that grow optimally in media containing 3%-15% (w/v) salt. They are represented by a heterogeneous group of microorganisms included in many different genera. Gram-negative moderately halophilic bacteria have been studied in more detail, but studies on gram-positive species are more scarce. Recent studies carried out by our research group on gram-positive moderate halophiles have permitted clarifying their taxonomic and phylogenetic position and describing new species. Thus, we have isolated six strains from ponds of salterns that show phenotypic and genotypic characteristics similar to those of Nesterenkonia halobia (formerly Micrococcus halobius), a moderately halophilic gram-positive coccus that was described on the basis of a single strain. Our data demonstrate quite clearly that they are members of this species and contribute to a better description of these moderately halophilic cocci. Similarly, a study of a large number of gram-positive moderately halophilic rods that were able to produce endospores led us to describe a new species, designated Bacillus salexigens. Further, isolates grouped in other three phenons, obtained by numerical taxonomy analysis and showing phenotypic features quite similar to those of this species, represent different genomovars, with very low DNA-DNA homology. Although they might represent additional new species, it will be necessary to determine new phenotypic features to differentiate them from previously described Bacillus species. We have also studied the viability of some old enrichments provided by B.E. Volcani, which were set up in 1936. We isolated 31 gram-positive motile endospore-forming rods that, according to their phenotypic characteristics, could represent a new species of the genus Bacillus.
中度嗜盐细菌是一类在含有3%-15%（w/v）盐的培养基中生长最佳的微生物。它们由许多不同属的多种微生物组成。革兰氏阴性中度嗜盐细菌已得到更详细的研究，但对革兰氏阳性菌的研究较少。我们研究小组最近对革兰氏阳性中度嗜盐菌进行的研究，明确了它们的分类和系统发育位置，并描述了新物种。因此，我们从盐场池塘中分离出六株菌株，它们表现出与嗜盐涅斯捷连科氏菌（以前称为嗜盐微球菌）相似的表型和基因型特征，嗜盐涅斯捷连科氏菌是一种基于单一菌株描述的中度嗜盐革兰氏阳性球菌。我们的数据清楚地表明，它们是该物种的成员，有助于更好地描述这些中度嗜盐球菌。同样，对大量能够产生内生孢子的革兰氏阳性中度嗜盐杆菌的研究，使我们描述了一个新物种，命名为嗜盐芽孢杆菌。此外，通过数值分类分析获得的、归为其他三个表型组的分离株，其表型特征与该物种非常相似，代表不同的基因组变种，DNA-DNA同源性非常低。尽管它们可能代表其他新物种，但有必要确定新的表型特征，以将它们与先前描述的芽孢杆菌属物种区分开来。我们还研究了B.E. 沃尔卡尼于1936年设立的一些旧富集培养物的活力。我们分离出31株革兰氏阳性、能运动、形成内生孢子的杆菌，根据它们的表型特征，可能代表芽孢杆菌属的一个新物种。
