Araújo Juan, Flores-Félix José David, Igual José M, Peix Alvaro, González-Andrés Fernando, Díaz-Alcántara César Antonio, Velázquez Encarna
Facultad de Ciencias Agronómicas y Veterinarias, Universidad Autónoma de Santo Domingo, Santo Domingo, Dominican Republic.
Departamento de Microbiología y Genética and Instituto Hispanoluso de Investigaciones Agrarias (CIALE), Universidad de Salamanca, Salamanca, Spain.
Int J Syst Evol Microbiol. 2017 Jul;67(7):2236-2241. doi: 10.1099/ijsem.0.001932. Epub 2017 Jul 3.
Two slow-growing strains, AMBPC1010T and AMBPC1011, were isolated from nodules of Cajanus cajan in the Dominican Republic. 16S rRNA gene analysis placed these strains within the genus Bradyrhizobium, being phylogenetically equidistant to several species of this genus. Analysis of the recA and atpD genes showed that the strains isolated belong to a cluster containing the strains Bradyrhizobium ottawaense OO99T, 'Bradyrhizobium americanum' CMVU44 and Bradyrhizobium daqingense CCBAU 15774T, and presented similarity values lower than 96 % for both genes with respect to the strains nodulating C. cajan. DNA-DNA hybridization analysis showed averages of 36, 40 and 39 % relatedness with respect to the representative strains of Bradyrhizobium ottawaense, 'Bradyrhizobium americanum' and Bradyrhizobium daqingense, respectively. Phenotypic characteristics also differed from those of the most closely related species of the genus Bradyrhizobium. Therefore, based on the data obtained in this study, we propose to classify the strains AMBPC1010T (=LMG 29967T=CECT 9227T) and AMBPC1011 into a novel species named Bradyrhizobium cajani sp. nov.
从多米尼加共和国木豆的根瘤中分离出两株生长缓慢的菌株，即AMBPC1010T和AMBPC1011。16S rRNA基因分析将这些菌株归入慢生根瘤菌属，在系统发育上与该属的几个物种距离相等。recA和atpD基因分析表明，分离出的菌株属于一个包含渥太华慢生根瘤菌OO99T、“美洲慢生根瘤菌”CMVU44和大庆慢生根瘤菌CCBAU 15774T的簇，并且这两个基因与结瘤木豆的菌株相比，相似性值均低于96%。DNA-DNA杂交分析表明，与渥太华慢生根瘤菌、“美洲慢生根瘤菌”和大庆慢生根瘤菌的代表菌株的平均相关性分别为36%、40%和39%。表型特征也与慢生根瘤菌属关系最密切的物种不同。因此，根据本研究获得的数据，我们建议将菌株AMBPC1010T（=LMG 29967T=CECT 9227T）和AMBPC1011归类为一个新物种，命名为木豆慢生根瘤菌（Bradyrhizobium cajani sp. nov.）。
