Brevundimonas halotolerans sp. nov., Brevundimonas poindexterae sp. nov. and Brevundimonas staleyi sp. nov., prosthecate bacteria from aquatic habitats.

Eight strains of Gram-negative, bacteroid-shaped, prosthecate bacteria, isolated from brackish water (MCS24T, MCS17 and MCS35), the marine environment (CM260, CM272 and CM282) and activated sludge (FWC40T and FWC43T), were characterized using a polyphasic approach. Analysis of 16S rRNA gene sequences determined that all strains were affiliated to the alphaproteobacterial genus Brevundimonas, forming three distinct phyletic lineages within the genus. The strains grew best with 5-30 g NaCl l(-1) at 20-30 degrees C. DNA G+C contents for strains MCS24T, FWC40T and FWC43T were between 65 and 67 mol%, in accordance with values reported previously for other species of the genus. Moreover, chemotaxonomic data and physiological and biochemical tests allowed the phenotypic differentiation of three novel species within the genus Brevundimonas, for which the names Brevundimonas halotolerans sp. nov. (type strain MCS24T =LMG 25346T =CCUG 58273T), Brevundimonas poindexterae sp. nov. (type strain FWC40T =LMG 25261T =CCUG 57883T) and Brevundimonas staleyi sp. nov. (type strain FWC43T =LMG 25262T =CCUG 57884T) are proposed.