Acidiphilium aminolytica sp. nov.: An acidophilic chemoorganotrophic bacterium isolated from acidic mineral environment.

Acidiphilium aminolytica is proposed for a species of the genusAcidiphilium. Acidiphilium aminolytica can be phenotypically differentiated from all other species of the genusAcidiphilium. The seven strains of this species that have been studied are Gram-negative, aerobic, mesophilic, non-sporeforming, motile, and rod-shaped bacteria. They grow between pH 3.0 and 6.0, but not at pH 6.5. They yield positive results in tests for hippuric acid hydrolysis, catalase and urease production. Oxidase, esculin hydrolysis, and β-galactosidase tests are negative. They can useD-glucose,D-galactose, inositol, sorbitol,L-lysine,L-glutamate,L-arginine, β-alanine,DL-4-aminobutyrate,DL-5-aminovalerate, sperimine, or diaminobutane as a sole carbon source, but cannot use elemental sulfur and ferrous iron as an energy source. The DNA base composition is 58.7-59.2 G+C mol%. The major isoprenoid quinone is ubiquinone with ten isoprene unit (Q-10). The major fatty acid is the C18:1 fatty acid. Two ornithine amide lipids, the C18:1 fatty acid esters of α-N-3-hydroxystearylornithyltaurine and α-N-3-hydroxystearylornithine, are detected as the polar aminolipid. DNA relatedness between this species and the other species ofAcidiphilium, the generaAcidomonas, andAcidobacterium was 29 to 2%. These results indicate, that this new species should be placed in the genusAcidiphilium. The type strain (strain 101) ofA. aminolytica is JCM 8796.