Paenibacillus radicis sp. nov., an endophytic bacterium isolated from maize root

A novel Gram-stain-positive, aerobic, endospore-forming, and rod-shaped strain designated 694 T was isolated from surface-sterilized root tissue of a maize planted in the Fangshan District of Beijing, People's Republic of China. A polyphasic taxonomic study was performed on the new isolate. On the basis of 16S rRNA gene sequence similarity studies, this isolate belongs to the genus Paenibacillus . High levels of 16S rRNA gene sequence similarity were found between strain 694 T and Paenibacillus xinjiangensis DSM 30034 T (98.5 %) and Paenibacillus glycanilyticus (98.1 %), respectively. However, the DNA-DNA hybridization values between strain 694 T and its close relatives P. xinjiangensis 16970 T and Paenibacillus algorifonticola CGMCC 1.10223 T were 30.0 % and 36.7 % respectively. The DNA G+C content of strain 694 T was determined to be 46.9 mol%. The predominant respiratory quinone was identified as menaquinone-7 and the polar lipid profile was found to be composed of the major lipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were found to be anteiso-C 15 : 0 (42.1 %), iso-C 15 : 0 (18.4 %), iso-C 16 : 0 (11.2 %) and C 16 : 0 (12.1 %). The results of physiological and biochemical tests and minor differences in the fatty acid profiles allowed a clear phenotypic differentiation of strain 694 T from the closely related species in the genus Paenibacillus. Strain 694 T is concluded to represent a novel species within the genus Paenibacillus , for which the name Paenibacillus radicis sp. nov. is proposed, with the type strain 694 T ( = CGMCC 1.15286 T  = DSM 100762 T ).