Identification of Acetobacter strains isolated from Indonesian sources, and proposals of Acetobacter syzygii sp nov., Acetobacter cibinongensis sp nov., and Acetobacter orientalis sp nov.

Forty-six strains of acetic acid bacteria newly isolated from flowers, frui ts, and fermented foods collected in Indonesia were taxonomically studied. They were Gram-negative rods, produced acetic acid from ethanol, oxidized a cetate and lactate to CO2 and H2O, and had 0-9 as the major ubiquinone syst em. On the basis of DNA-DNA similarity, all strains studied, including type strains and reference strains of the genus Acetobacter, were separated int o eleven groups (Groups I to XI). Of the 46 isolates, two isolates were inc luded in Group II and identified as Acetobacter pasteurianus, five in Group IV as A. orleanensis, 16 in Group V as A. lovaniensis, five in Group VII a s A. indonesiensis, and three in Group VIII as A. tropicalis. The remaining 15 isolates constituted three new groups based on DNA-DNA similarity; four isolates were included in Group IX, two in Group X, and nine in Group XI. No isolates were identified as A. aceti (Group I), A. peroxydans (Group III ), and A. estunensis (Group VI). Phylogenetic analysis based on 16S rDNA se quences of representative strains of the Groups indicated belonging to the strains of the genus Acetobacter. On the basis of DNA base composition, DNA -DNA similarity, and 16S rDNA sequences, three new species of the genus Ace tobacter are proposed: Acetobacter syzygii sp. nov. for Group IX, Acetobact er cibinongensis sp. nov. for Group X, and Acetobacter orientalis sp. nov. for Group XI. The distribution of Acetobacter strains in Indonesia is discu ssed in light of isolation sources.