Durán David, Rey Luis, Navarro Albert, Busquets Antonio, Imperial Juan, Ruiz-Argüeso Tomás
Centro de Biotecnología y Genómica de Plantas (CBGP) and Departamento de Biotecnología (ETSI Agrónomos), Campus de Montegancedo, Universidad Politécnica de Madrid, 28223 Pozuelo de Alarcón, Madrid, Spain.
VAERSA, Centro para la Investigación y Experimentación Forestal (CIEF), Servicio de Vida Silvestre, Conselleria de Infraestructuras, Territorio y Medio Ambiente, Generalitat Valenciana. Avda. Comarques del Pais Valencià, 114, 46930 Quart de Poblet, Valencia, Spain.
Syst Appl Microbiol. 2014 Jul;37(5):336-41. doi: 10.1016/j.syapm.2014.05.002. Epub 2014 May 22.
Bacterial strains isolated from nitrogen-fixing nodules of Lupinus mariae-josephae have been characterized following genetic, phenotypic and symbiotic approaches. Analysis of 16S rRNA genes placed them in a group together with Bradyrhizobium elkanii USDA 76(T), B. pachyrhizi PAC48(T), B. jicamae PAC68(T), 'B. retamae' Ro19(T) and B. lablabi CCBAU 23086(T) with over 99.0% identity. Phylogenetic analysis of concatenated housekeeping genes, recA, atpD and glnII, suggested that L. mariae-josephae strains represent a new Bradyrhizobium species, closely related to B. lablabi CCBAU 23086(T), B. jicamae PAC68(T) and 'B. retamae' Ro19(T) with 92.1, 91.9 and 90.8% identity, respectively. These results are consistent with overall genomic identities calculated as Average Nucleotide Identity (ANIm) using draft genomic sequences obtained for relevant strains. While L. mariae-josephae strains LmjM3(T)/LmjM6 exhibited a 99.2% ANIm value, they were significantly distant (<93% ANIm) from type strains of their closest species ('B. retamae' Ro19(T), B. lablabi CCBAU 23086(T) and B. jicamae PAC68(T)). Whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (WC-MALDI-TOF-MS) analysis of proteomic patterns of the same strains was consistent with these results. The symbiosis-related genes nodC, nodA and nifH genes from strains nodulating L. mariae-josephae were phylogenetically related to those from 'B. retamae' Ro19(T), but divergent from those of strains that nodulate other lupine species. Based on genetic, genomic, proteomic and phenotypic data presented in this study, L. mariae-josephae nodulating strains LmjM3(T), LmjM6 and LmjM2 should be grouped within a new species for which the name Bradyrhizobium valentinum sp. nov. is proposed (type strain LmjM3(T)=CECT 8364(T), LMG 2761(T)).
从玛丽亚-约瑟芬羽扇豆固氮根瘤中分离出的细菌菌株已通过遗传、表型和共生方法进行了特征分析。16S rRNA基因分析将它们与埃尔坎慢生根瘤菌USDA 76(T)、大豆慢生根瘤菌PAC48(T)、豆薯慢生根瘤菌PAC68(T)、“刺槐慢生根瘤菌”Ro19(T)和扁豆慢生根瘤菌CCBAU 23086(T)归为一组，同一性超过99.0%。对看家基因recA、atpD和glnII串联进行系统发育分析表明，玛丽亚-约瑟芬羽扇豆菌株代表一个新的慢生根瘤菌物种，与扁豆慢生根瘤菌CCBAU 23086(T)、豆薯慢生根瘤菌PAC68(T)和“刺槐慢生根瘤菌”Ro19(T)密切相关，同一性分别为92.1%、91.9%和90.8%。这些结果与使用相关菌株的基因组草图序列计算的平均核苷酸同一性(ANIm)得出的总体基因组同一性一致。虽然玛丽亚-约瑟芬羽扇豆菌株LmjM3(T)/LmjM6的ANIm值为99.2%，但它们与最接近物种的模式菌株（“刺槐慢生根瘤菌”Ro19(T)、扁豆慢生根瘤菌CCBAU 23086(T)和豆薯慢生根瘤菌PAC68(T)）有显著差异（<93% ANIm）。对相同菌株的蛋白质组模式进行的全细胞基质辅助激光解吸/电离飞行时间质谱(WC-MALDI-TOF-MS)分析与这些结果一致。来自结瘤玛丽亚-约瑟芬羽扇豆菌株的共生相关基因nodC、nodA和nifH基因在系统发育上与来自“刺槐慢生根瘤菌”Ro19(T)的基因相关，但与结瘤其他羽扇豆物种的菌株的基因不同。基于本研究中提供的遗传、基因组、蛋白质组和表型数据，结瘤玛丽亚-约瑟芬羽扇豆的菌株LmjM3(T)、LmjM6和LmjM2应归为一个新物种，为此提议命名为瓦伦丁慢生根瘤菌（Bradyrhizobium valentinum sp. nov.）（模式菌株LmjM3(T)=CECT 8364(T)，LMG 2761(T)）。
