Seven novel species of Acinetobacter isolated from activated sludge

Thirteen isolates of Acinetobacter were obtained from activated sludge plants in Victoria, Australia. Earlier 16S-23S rDNA genomic fingerprinting and partial 16S rDNA sequence data had suggested that these isolates might contain previously undescribed species. This view was confirmed here. A polyphasic taxonomic approach involving phenotypic characterization, near-complete 16S rDNA sequence data and DNA-DNA hybridization analyses support the view that seven novel genomic species can be differentiated in this group of isolates. However, when fluorescence in situ hybridization (FISH) studies were performed with a 16S-rRNA-targeted probe specific for the genus Acinetobacter, used to identify Acinetobacter in activated sludge plants, all these strains responded positively. This suggests that these isolates would not have been missed in earlier FISH studies where their role as polyphosphate-accumulating bacteria has been questioned. This report describes these isolates and proposes that they be named Acinetobacter baylyi (type strain B2(T) = DSM 14961(T) = CIP 107474(T)), Acinetobacter bouvetii (type strain 4B02(T) = DSM 14964 (T) = CIP 107468(T)), Acinetobacter grimontii (type strain 17A04(T) = DSM 14968(T) = CIP 107470(T)), Acinetobacter tjernbergiae (type strain 7N16(T) = DSM 1497(T) = CIP 107465(T)), Acinetobacter towneri (type strain AB1110(T) = DSM 14962(T) = CIP 107472 T), Acinetobacter tandoii (type strain 4N13(T) = DSM 14670(T) = CIP 107469(T)) and Acinetobacter gerneri (type strain 9A01(T) = DSM 14967(T) = CIP 107464(T)).