Acetobacter ghanensis sp. nov., a novel acetic acid bacterium isolated from traditional heap fermentations of Ghanaian cocoa beans

1 BCCM/LMG Bacteria Collection, Faculty of Sciences, Ghent University, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium 2 Research Group of Industrial Microbiology and Food Biotechnology, Department of Applied Biological Sciences and Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium 3 Laboratory of Microbiology, Faculty of Sciences, Ghent University, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium Correspondence Ilse Cleenwerck Ilse.Cleenwerck{at}ugent.be Twenty-three acetic acid bacteria, isolated from traditional heap fermentations of Ghanaian cocoa beans, were subjected to a polyphasic taxonomic study. The isolates were catalase-positive, oxidase-negative, Gram-negative rods. They oxidized ethanol to acetic acid and were unable to produce 2-ketogluconic acid, 5-ketogluconic acid and 2,5-diketogluconic acid from glucose; therefore, they were tentatively identified as Acetobacter species. 16S rRNA gene sequencing and phylogenetic analysis confirmed their position in the genus Acetobacter , with Acetobacter syzygii and Acetobacter lovaniensis as their closest phylogenetic neighbours. (GTG) 5 -PCR fingerprinting grouped the strains in a cluster that did not contain any type strains of members of the genus Acetobacter . DNA–DNA hybridization with the type strains of all recognized Acetobacter species revealed DNA–DNA relatedness values below the species level. The DNA G+C contents of three selected strains were 56.9–57.3 mol%. The novel strains had phenotypic characteristics that enabled them to be differentiated from phylogenetically related Acetobacter species, i.e. they were motile, did not produce 2-ketogluconic acid or 5-ketogluconic acid from glucose, were catalase-positive and oxidase-negative, grew on yeast extract with 30 % glucose, grew on glycerol (although weakly) but not on maltose or methanol as carbon sources, and did not grow with ammonium as sole nitrogen source and ethanol as carbon source. Based on the genotypic and phenotypic data, the isolates represent a novel species of the genus Acetobacter for which the name Acetobacter ghanensis sp. nov. is proposed. The type strain is R-29337 T (=430A T =LMG 23848 T =DSM 18895 T ). Abbreviations: AAB, acetic acid bacteria The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of strains R-29337 T , 444B and 384 are EF030713 , DQ887337 and DQ887338 , respectively. A maximum-parsimony tree based on 16S rRNA gene sequences of Acetobacter ghanensis sp. nov.