Laboratoire d'Ecologie Microbienne, Faculté des Sciences de la Nature et de la Vie, Université de Bejaia, 06000 Bejaia, Algeria.
Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM, 28223 Pozuelo de Alarcón, Madrid, Spain; Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, UPM, 28040 Madrid, Spain.
Syst Appl Microbiol. 2018 Jul;41(4):333-339. doi: 10.1016/j.syapm.2018.03.004. Epub 2018 Apr 4.
We have characterized genetic, phenotypic and symbiotic properties of bacterial strains previously isolated from nitrogen-fixing nodules of Retama sphaerocarpa from Northern Algeria. Phylogenetic analyses of 16S rRNA genes and three concatenated housekeeping genes, recA, atpD and glnII, placed them in a new divergent group that is proposed to form a new Bradyrhizobium species, Bradyrhizobium algeriense sp. nov. (type strain RST89, LMG 27618 and CECT 8363). Based on these phylogenetic markers and on genomic identity data derived from draft genomic sequences, Bradyrhizobium valentinum LmjM3, Bradyrhizobium lablabi CCBAU 23086, Bradyrhizobium retamae Ro19, and Bradyrhizobium jicamae PAC68 are the closest relatives of B. algeriense RST89, with sequence identities of 92-94% and Average Nucleotide Identities (ANIm) under 90%, well below the 95-96% species circumscription threshold. Likewise, a comparison of whole-cell proteomic patterns, estimated by Matrix-Assisted Laser Desorption/Ionization-Time-of-Flight (MALDI-TOF) mass spectrometric analysis, yielded almost identical spectra between B. algeriense strains but significant differences with B. valentinum, Bradyrhizobium paxllaeri, Bradyrhizobium icense, B. lablabi, B. jicamae and B. retamae. A phylogenetic tree based on symbiotic gene nodC revealed that the B. algeriense sequences cluster with sequences from the Bradyrhizobium symbiovar retamae, previously defined with B. retamae strains isolated from Retama monosperma. B. algeriense strains were able to establish effective symbioses with Retama raetam, Lupinus micranthus, Lupinus albus and Genista numidica, but not with Lupinus angustifolius or Glycine max.
我们对从阿尔及利亚北部的 Retama sphaerocarpa 固氮根瘤中分离出的细菌菌株的遗传、表型和共生特性进行了表征。16S rRNA 基因和三个串联的看家基因（recA、atpD 和 glnII）的系统发育分析将它们置于一个新的分歧群中，该群被提议形成一个新的慢生根瘤菌物种，即 Algeriense 慢生根瘤菌 sp. nov.（模式菌株 RST89、LMG 27618 和 CECT 8363）。基于这些系统发育标记物和源自基因组草图序列的基因组同源性数据，Valentinum 慢生根瘤菌 LmjM3、Lablabi 慢生根瘤菌 CCBAU 23086、Retamae 慢生根瘤菌 Ro19 和 Jicamae 慢生根瘤菌 PAC68 是 B. algeriense RST89 的最亲近的亲缘关系，序列同一性为 92-94%，平均核苷酸同一性（ANI）低于 90%，远低于 95-96%的种界定阈值。同样，通过基质辅助激光解吸/电离飞行时间（MALDI-TOF）质谱分析估算的全细胞蛋白质组模式比较表明，B. algeriense 菌株之间的蛋白质图谱几乎相同，但与 Valentinum 慢生根瘤菌、Paxllaeri 慢生根瘤菌、icense 慢生根瘤菌、Lablabi 慢生根瘤菌、Jicamae 慢生根瘤菌和 Retamae 慢生根瘤菌存在显著差异。基于共生基因 nodC 的系统发育树表明，B. algeriense 序列与先前从 Retama monosperma 中分离出的 Retamae 慢生根瘤菌共生种的序列聚类。B. algeriense 菌株能够与 Retama raetam、 Lupinus micranthus、 Lupinus albus 和 Genista numidica 建立有效的共生关系，但不能与 Lupinus angustifolius 或 Glycine max 建立共生关系。
