Paenibacillus anseongense sp. nov. a Silver Nanoparticle Producing Bacterium Isolated from Rhizospheric Soil

A silver nanoparticle (AgNP) producing, Gram stain-positive, aerobic, motile, and rod-shaped novel bacterial strain, designated as MAH-34 ^T was isolated from rhizospheric soil of magnolia tree. The colonies were creamy white, smooth, circular, and 0.9-2.0 mm in diameter when grown on R2A agar. Strain MAH-34 ^T was found to be able to grow at 10-37 °C, at pH 6.0-9.5, and at 0-1% NaCl. The strain showed activity for both catalase, and oxidase tests, and was able to rapid synthesis of AgNPs. The TEM image revealed the spherical shape of biosynthesized AgNPs, and the size was 5 to 15 nm. Based on 16S rRNA gene sequence comparisons, the isolate was shown to be a member of genus Paenibacillus, and the close type strains were Paenibacillus chondroitinus DSM 5051 ^T (98.3%), Paenibacillus aceris KUDC4121^T (98.2%), Paenibacillus nebraskensis JJ-59 ^T (97.8%), Paenibacillus alginolyticus DSM 5050 ^T (97.6%), Paenibacillus ferrarius CY1^T (97.4%), Paenibacillus frigoriresistens YIM 016 ^T (97.3%), and Paenibacillus pocheonensis Gsoil 1138 ^T (97.3%). Strain MAH-34 ^T had a genome size of 8,647,010 bp. The genomic G + C content was 46.0 mol %. The major isoprenoid quinone was determined as menaquinone-7 (MK-7). The major cellular fatty acids were determined as C_{15:0 anteiso}, and C_{16:0 iso}. Based on the DNA-DNA hybridization results, genotypic analysis, chemotaxonomic, and physiological data, strain MAH-34 ^T represents a novel species, for which the name Paenibacillus anseongense sp. nov. is proposed, with MAH-34 ^T as the type strain (= KACC 19974 ^T = CGMCC1.16610 ^T).