Abstract A strain (strain IsBd1) of anaerobic bacterium was isolated in pure culture from a sand sample of Lake Kasumigaura using 1,4-butanediol as a sole electron-donor source, and was characterized. The bacterium was motile with a single polar flagellum and stained gram-negative. Spores were never observed. Sulfate, sulfite, thiosulfate, and elemental sulfur were reduced with concomitant growth. Even in the presence of excess sulfate, 1,4-butanediol and 1,5-pentanediol were oxidized stoichiometrically to 4-hydroxybutyrate and 5-hydroxyvalerate, respectively; 2-propanol and 2-butanol were oxidized stoichiometrically to corresponding ketones. Interspecies hydrogen transfer occurred between the isolate and Methanospirillum hungatei with ethanol, 1,3-butanediol, 1,4-butanediol, 1-butanol, 2-butanol, 2-methoxyethanol, 1,5-pentanediol, 1,3-propanediol, 1-propanol, and 2-propanol. Chemolithoheterotrophic growth was possible with formate or hydrogen and acetate in the presence of sulfate. Acetoin was fermented to acetate, 2,3-butanediol, and ethanol. Fumarate and l -malate were fermented to acetate and succinate. S-1,2-Propanediol was fermented to 1-propanol and propionate, but a racemic mixture was not fermented. When formate or hydrogen was supplied, fumarate and l -malate were reduced stoichiometrically to succinate with growth. The DNA base ratio of the isolate was 53 mol% guanine plus cytosine. Strain IsBd1 was identified as a member of the genus Desulfovibrio.