Pascual Javier, Wüst Pia K, Geppert Alicia, Foesel Bärbel U, Huber Katharina J, Overmann Jörg
Department of Microbial Ecology and Diversity Research, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.
Department of Microbial Ecology and Diversity Research, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany; Technical University Braunschweig, Braunschweig, Germany.
Syst Appl Microbiol. 2015 Dec;38(8):534-44. doi: 10.1016/j.syapm.2015.08.001. Epub 2015 Sep 28.
Despite their high phylogenetic diversity and abundance in soils worldwide, Acidobacteria represent an enigmatic bacterial phylum. Four novel Acidobacteria strains were isolated from Namibian semiarid savannah soils using low-nutrient cultivation media and extended incubation periods. 16S rRNA gene sequence analyses placed the isolates within Acidobacteria subdivision 4. Sequence identities with their closest relatives Aridibacter famidurans and Blastocatella fastidiosa were ≤94.9%. The Gram-negative, non-motile, rod-shaped, aerobic, and chemoorganotrophic bacteria grew at minimum doubling times of 5-14h and formed tiny white to pinkish colonies. Major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, and phosphatidylglycerol. The major isoprenoid quinone was MK-8. The major fatty acid methyl esters comprised iso-C15:0, iso-C15:1H/C13:0 3-OH, and C16:1ω7c/C16:1ω6c. Based on a polyphasic taxonomic characterization, strain Ac_18_E7(T) (=DSM 26557(T)=LMG 28656(T)) represented a novel species and genus, Tellurimicrobium multivorans gen. nov., sp. nov. The other strains constituted three independent species of the novel genus Stenotrophobacter gen. nov., Stenotrophobacter terrae sp. nov. (Ac_28_D10(T)=DSM 26560(T)=LMG 28657(T)), S. roseus sp. nov. (Ac_15_C4(T)=DSM 29891(T)=LMG 28889(T)), and S. namibiensis sp. nov. (Ac_17_F2(T)=DSM 29893(T)=LMG 28890(T)). These isolates doubled the number of established species and permitted the description of higher taxa of Acidobacteria subdivision 4. The family Blastocatellaceae fam. nov. is proposed in order to summarize the currently known oligotrophic, slightly acidophilic to neutrophilic mesophiles from arid soils. The superordinated order Blastocatellales ord. nov. and Blastocatellia classis nov. also include the terrestrial species Pyrinomonas methylaliphatogenes and the anoxygenic photoheterotrophic species Chloracidobacterium thermophilum from microbial mats.
尽管嗜酸菌在全球土壤中具有高度的系统发育多样性和丰富度，但它们仍是一个神秘的细菌门类。利用低营养培养基和延长培养时间，从纳米比亚半干旱稀树草原土壤中分离出4株新型嗜酸菌菌株。16S rRNA基因序列分析将这些分离菌株归入嗜酸菌第4亚类。它们与其最接近的亲缘种干旱嗜杆菌（Aridibacter famidurans）和苛求芽孢杆菌（Blastocatella fastidiosa）的序列同一性≤94.9%。这些革兰氏阴性、不运动、杆状、需氧且化能有机营养型细菌的最小倍增时间为5 - 14小时，形成微小的白色至粉红色菌落。主要极性脂为双磷脂酰甘油、磷脂酰乙醇胺、磷脂酰胆碱和磷脂酰甘油。主要类异戊二烯醌为MK - 8。主要脂肪酸甲酯包括异C15:0、异C15:1H/C13:0 3 - OH以及C16:1ω7c/C16:1ω6c。基于多相分类特征，菌株Ac_18_E7(T)（=DSM 26557(T)=LMG 28656(T)）代表一个新的属和种，即多食碲微菌（Tellurimicrobium multivorans），属名新属，种名新种。其他菌株构成了新属窄养杆菌属（Stenotrophobacter gen. nov.）的三个独立种，即土壤窄养杆菌（Stenotrophobacter terrae sp. nov.）（Ac_28_D10(T)=DSM 26560(T)=LMG
