|Budget Amount *help
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥1,600,000 (Direct Cost: ¥1,600,000)
Acidophilic heterotrophic bacteria were detected in and isolated from strongly acid mine drainage waters at the Matsuo sulfur and iron-sulfide mine in Iwate Prefecture. These bacteria (66 isolates) were compared morphologically, nutritionally, and chemotaxonomically. Viable bacterial numbers counted by dilution plate method (basal salts medium+ various organic nutrients, pH 3-4) were very small although total counts were very large (10^4-10^6 cells/ml). All of the strains isolated were gram negative, rod shaped, strictly aerobic, mesophilic, strictly acidophilic (optimum growth pH, 3-4), hydrogen sulfide production positive, catalase positive, indole production negative, not heat-tolerant (not spore-forming). Oxidase activities were varied among strains. They utilized various carbon sources, including glucose, citrate, malate, and glutamic acid, and could utilize urea as source of nitrogen. Acetate inhibited the growth of all strains. NaCl tolerance (3-7.5%) and utilization of glucose (0.5-15%), yeast extract (0.1-0.5%) and trypticase soy broth (0.1-5%) were examined and found to be variable among strains. The isolates were classified into three large groups based on many phenotypical characteristics and further into two large groups based on cellular fatty acid composition. We describe the taxonomical position of these acidophilic heterotrophic bacteria and the relationship of them to other acidophilic heterotrophs (Acidiphilium sp.) hitherto reported.