During a study of endophytic nitrogen-fixing bacteria present in the wild rice species , eight novel isolates were obtained from surface-sterilized roots and classified in the genus on the basis of almost-complete 16S rRNA gene sequence analysis. These strains can nodulate and . The highly similar protein patterns, DNA fingerprint patterns of insertion sequence-based PCR (IS-PCR) and DNA–DNA hybridizations showed that these novel isolates were members of the same species. The closest phylogenetic relatives of the representative strain Alt 505 of the novel group were CFN 42 and CCBAU 71714, with 96.2 and 96.0 % 16S rRNA gene sequence similarity, respectively. Low DNA–DNA relatedness with the type strains of , , , and and differences in IS-PCR fingerprinting patterns, SDS-PAGE of proteins, antibiotic resistance, phenotypic tests and comparison of cellular fatty acids with species indicated that the novel group of isolates were distinct from previously described species. Based on these results, we propose to place them in a novel species, as sp. nov. The type strain is Alt 505 (=LMG 24253 =CGMCC 1.7048).


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Transmission electron micrograph of cells of strain Alt 505 . [PDF](16 KB)


DNA-DNA hybridization results and a list of characteristics of two representative novel isolates. [PDF](97 KB)

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