Paenibacillus nanchangensis sp. nov., a Nitrogen-Fixing Strain Isolated from Agricultural Soil.

A Gram-stain-positive, nonmotile, endospore-forming and short rod bacterium, designated as CN-4, was isolated from farm soil collected at Nanchang city, PR China. Strain CN-4 grew at 15-42 °C (optimum at 30 °C), pH 6.0-9.0 (optimum at pH 7.0) with NaCl content of 0-4% (optimum at 0.5%), and was able to fix nitrogen. The result of 16S rRNA gene sequence analysis found that strain CN-4 was most closely associated with Paenibacillus albidus Q4-3 (96.8% similarity), P. apii 7124 (96.7% similarity) and P. tianjinensis TB2019 (96.5% similarity). In the phylogenetic trees, strain CN-4 was clustered in genus Paenibacillus but formed a distinct clade. The major cellular fatty acids (≥ 5%) were anteiso-C, iso-C, C, and anteiso-C, the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, three unidentified aminophospholipids, and five unidentified lipids. The cell wall peptidoglycan was meso-DAP, DNA G + C content was 53.7%. According to the taxonomic data, strain CN-4 represents a new species within genus Paenibacillus, as Paenibacillus nanchangensis sp. nov, with strain CN-4 (= MCCC 1K09410 = KCTC 43751) as type strain.