Paenibacillus rhizosphaerae sp. nov., isolated from the rhizosphere of Cicer arietinum

Abstract

Two sporulating bacterial strains designated CECAP06(T) and CECAP16 were isolated from the rhizosphere of the legume Cicer arietinum in Argentina. Almost-complete 16S rRNA gene sequences identified the isolates as a Paenibacillus species. It was most closely related to Paenibacillus cineris LMG 18439(T) (99.6 % sequence similarity), Paenibacillus favisporus LMG 20987(T) (99.4 % sequence similarity) and Paenibacillus azoreducens DSM 13822(T) (97.7 % sequence similarity). The cells of this novel species were motile, sporulating, rod-shaped, Gram-positive and strictly aerobic. The predominant fatty acids were anteiso-C(15 : 0), C(16 : 0) and iso-C(16 : 0). The DNA G+C content of strains CECAP06(T) and CECAP16 was 51.3 and 50.9 mol%, respectively. Growth was observed from many carbohydrates, but gas production was not observed from glucose. Catalase and oxidase activities were present. The isolates produced beta-galactosidase and hydrolysed aesculin. Gelatinase, caseinase and urease were not produced. The results of DNA-DNA hybridization showed that the strains from this study constitute a novel species of the genus Paenibacillus, for which the name Paenibacillus rhizosphaerae sp. nov. is proposed. The type strain is CECAP06(T) (=LMG 21955(T) = CECT 5831(T)).