Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea.
Department of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea.
Int J Syst Evol Microbiol. 2024 Oct;74(10). doi: 10.1099/ijsem.0.006554.
Two separate bacterial strains, PMTSA4 and PMR2A8, were isolated from the rhizospheric soils of bell pepper plants grown in a plant nursery. These strains are Gram-negative, non-motile and rod-shaped and grow in aerobic conditions. They exhibit a positive reaction for catalase activity but negative results for oxidase activity. Phylogenetic analysis of the 16S rRNA gene sequences revealed that the strains PMTSA4 and PMR2A8 are closely related to ICH-30 (95.6%, respectively), 10Alg 130 (95.5%) and KMM 9535 (95.3%), aligning them within the genus . Digital DNA-DNA hybridization (dDDH) values and average nucleotide identities (ANIs) of the whole-genome sequences for the two strains and related species were significantly below the established thresholds for prokaryotic species delineation (<70% for dDDH and <95% for ANI). The observed values were as follows: LMG 4008 (dDDH: 19.8% and ANI: 75.5%), ICH-30 (dDDH: 18.6% and ANI: 73.3%) and WWJ 16 (dDDH: 18.5% and ANI: 72.0%). The strains have genome sizes of 3 068 185 bp and 3 068 330 bp, with a G+C content of 32.5 mol%. In phenotypic characterization, the new strains grew at 10-35 °C and tolerated up to 4% NaCl at pH 5-9 (optimum pH 8). The predominant cellular fatty acids were observed to be iso-C, iso-C 3-OH and iso-C 3-OH. Menaquinone-6 was the predominant quinone. Considering the results from phenotypic, chemotaxonomic, phylogenetic and genomic analyses, it is proposed that the strains PMTSA4 and PMR2A8 represent a novel species within the genus .
从生长在苗圃中的辣椒植物的根际土壤中分离出两株分离菌，PMTSA4 和 PMR2A8。这些菌株是革兰氏阴性、非运动和杆状的，在需氧条件下生长。它们对过氧化氢酶活性呈阳性反应，但对氧化酶活性呈阴性结果。16S rRNA 基因序列的系统发育分析表明，菌株 PMTSA4 和 PMR2A8 与 ICH-30（分别为 95.6%）、10Alg 130（95.5%）和 KMM 9535（95.3%）密切相关，在属内排列. 两株菌和相关种的全基因组序列的数字 DNA-DNA 杂交（dDDH）值和平均核苷酸同一性（ANI）明显低于用于原核种划界的建立阈值（dDDH<70%和 ANI<95%）。观察到的值如下：LMG 4008（dDDH：19.8%和 ANI：75.5%）、ICH-30（dDDH：18.6%和 ANI：73.3%）和 WWJ 16（dDDH：18.5%和 ANI：72.0%）。这些菌株的基因组大小分别为 3068185 bp 和 3068330 bp，G+C 含量为 32.5 mol%。在表型特征方面，新菌株在 10-35°C 下生长，在 pH 5-9（最佳 pH 8）时耐受高达 4%的 NaCl。主要的细胞脂肪酸为 iso-C、iso-C 3-OH 和 iso-C 3-OH。menaquinone-6 是主要的醌。考虑到表型、化学分类、系统发育和基因组分析的结果，建议菌株 PMTSA4 和 PMR2A8 代表属内的一个新种。
