Abstract：
Aeschynomene indica has a distinctive symbiosis with Bradyrhizobium in which nodulation is Nod factor-independent. In this study, we characterised three Gram-negative and rod-shaped strains (83002T, 81013 and 83012) isolated from root nodules of Aeschynomene indica in Shandong Peninsula. The major cellular fatty acids of isolates were C16:0, C18:0, C18:1 ω7c 11-methyl, summed feature 3 and summed feature 8. The major polar lipids were phosphatidylethanolamine (PE), aminolipids (AL) and phosphatidylcholine (PC). Phylogenetic analysis based on the 16S rRNA locus showed that they belonged to the Bradyrhizobium genus, and shared the highest similarity to the type strains Bradyrhizobium oligotrophicum S58T and Bradyrhizobium denitrificans LMG 8443T. As expected, analysis of concatenated sequences of six housekeeping genes (atpD, recA, glnII, dnaK, gyrB, and rpoB) and nifH gene proposed that these three strains formed a distinct clade within the genus Bradyrhizobium. The highest average nucleotide identity and DNA-DNA hybridization values of the three strains in comparison to the closest Bradyrhizobium species were 87.5% and 65.3%, respectively, which are far below the threshold of species delineation, and thus confirmed the three strains as a new species. The genome size of strain 83002T is 7.52 Mbp, and the DNA G+C content is 65.42 mol%. Strain 83002T (=KCTC 82266T=MCCC 1K04775T) was chosen as the type strain of the new species, for which the name Bradyrhizobium aeschynomenes sp. nov. was proposed.
摘要：
Aeschynomeneindica与缓生根瘤菌具有独特的共生关系，其中结瘤与Nod因子无关。在这项研究中,我们表征了三种革兰氏阴性和杆状菌株(83002T，81013和83012）从山东半岛的伊沙诺明印度根瘤中分离。分离物的主要细胞脂肪酸是C16：0，C18：0，C18：1ω7c11-甲基，求和特征3和求和特征8。主要的极性脂质是磷脂酰乙醇胺（PE），氨基脂类(AL)和磷脂酰胆碱(PC)。基于16SrRNA基因座的系统发育分析表明，它们属于缓生根瘤菌属，与寡养根瘤菌S58T和反硝化根瘤菌LMG8443T型菌株的相似性最高。不出所料,六个管家基因的串联序列分析(atpD，recA，glnII,dnaK,gyrB,和rpoB）和nifH基因提出，这三个菌株在缓生根瘤菌属内形成了不同的进化枝。与最接近的根瘤菌相比，这三个菌株的平均核苷酸同一性和DNA-DNA杂交值最高，分别为87.5％和65.3％，分别,远低于物种划分的门槛，从而证实了这三个菌株是一个新的物种。菌株83002T的基因组大小为7.52Mbp,DNAG+C含量为65.42mol%。选择菌株83002T（=KCTC82266T=MCCC1K04775T）作为新物种的类型菌株，为此命名为缓生根瘤菌。11月。被提议了。
