Yamamoto S, Bouvet P J, Harayama S
Marine Biotechnology Institute, Kamaishi Laboratories, Kamaishi City, Japan.
Int J Syst Bacteriol. 1999 Jan;49 Pt 1:87-95. doi: 10.1099/00207713-49-1-87.
The phylogenetic relationships of 49 Acinetobacter strains, 46 of which have previously been classified into 18 genomic species by DNA-DNA hybridization studies, were investigated using the nucleotide sequence of gyrB, the structural gene for the DNA gyrase B subunit. The phylogenetic tree showed linkages between genomic species 1 (Acinetobacter calcoaceticus), 2 (Acinetobacter baumannii), 3 and TU13; genomic species 6, BJ15, BJ16 and BJ17; genomic species 5, BJ13 (synonym of TU14) and BJ14; genomic species 7 (Acinetobacter johnsonii), 10 and 11; and genomic species 8 and 9. The phylogenetic grouping of Acinetobacter strains based on gyrB genes was almost congruent with that based on DNA-DNA hybridization studies. Consequently, gyrB sequence comparison can be used to resolve the taxonomic positions of bacterial strains at the level of genomic species. However, minor discrepancies existed in the grouping of strains of genomic species 8, 9 and BJ17. The phylogenetic tree for these strains was reconstructed from the sequence of rpoD, the structural gene for the RNA polymerase sigma 70 factor. The latter tree was 100% congruent with the grouping based on DNA-DNA hybridization. The reliability of DNA-DNA hybridization may be superior to that of sequence comparison of a single protein-encoding gene in resolving closely related organisms since the former method measures the homologies between the nucleotide sequences of total genomic DNAs. Three strains that have not been characterized previously by DNA-DNA hybridization seem to belong to two new genomic species, one including strain ATCC 33308 and the other including strains ATCC 31012 and MBIC 1332.
对49株不动杆菌菌株的系统发育关系进行了研究，其中46株先前已通过DNA - DNA杂交研究被归类为18个基因组种。研究采用了DNA促旋酶B亚基的结构基因gyrB的核苷酸序列。系统发育树显示了基因组种1（醋酸钙不动杆菌）、2（鲍曼不动杆菌）、3和TU13之间的联系；基因组种6、BJ15、BJ16和BJ17之间的联系；基因组种5、BJ13（TU14的同义词）和BJ14之间的联系；基因组种7（约翰逊不动杆菌）、10和11之间的联系；以及基因组种8和9之间的联系。基于gyrB基因的不动杆菌菌株系统发育分组与基于DNA - DNA杂交研究的分组几乎一致。因此，gyrB序列比较可用于在基因组种水平上确定细菌菌株的分类地位。然而，在基因组种8、9和BJ17的菌株分组中存在一些细微差异。从RNA聚合酶σ70因子的结构基因rpoD的序列重建了这些菌株的系统发育树。后一棵系统发育树与基于DNA - DNA杂交的分组100%一致。在区分亲缘关系密切的生物体时，DNA - DNA杂交的可靠性可能优于单一蛋白质编码基因的序列比较，因为前一种方法测量的是总基因组DNA核苷酸序列之间的同源性。3株先前未通过DNA - DNA杂交进行鉴定的菌株似乎属于两个新的基因组种，一个包括菌株ATCC 33308，另一个包括菌株ATCC 31012和MBIC 1332。
