A Gram-stain-negative, non-spore-forming, rod-shaped bacterium, designated strain 1GBT, was isolated from anodic biofilms of a glucose-fed microbial fuel cell. Strain 1GBT was facultatively anaerobic and chemo-organotrophic, having both a respiratory and a fermentative type of metabolism, and utilized a wide variety of sugars as carbon and energy sources. Cells grown aerobically contained Q-8 as the major quinone, but excreted Q-9 and a small amount of Q-10 when cultured with an electrode serving as the sole electron acceptor. The G+C content of the genomic DNA of 1GBT was 54.5 mol%. Multilocus sequence typing (MLST) analysis showed that strain 1GBT represented a distinct lineage within the genus Raoultella (98.5–99.4 % 16S rRNA gene sequence similarity and 94.0–96.5 % sequence similarity based on the three concatenated housekeeping genes gyrA, rpoB and parC. Strain 1GBT exhibited DNA–DNA hybridization relatedness of 7–43 % with type strains of all established species of the genus Raoultella. On the basis of these phenotypic, phylogenetic and genotypic data, the name Raoultella electrica sp. nov. is proposed for strain 1GBT. The type strain is 1GBT ( = NBRC 109676T = KCTC 32430T).
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Funding
This study was supported by the:
Japanese Science and Technology Agency (JST
Japanese Society for the Promotion of Science
(Award 23656324)
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