Providencia sneebia sp. nov. and Providencia burhodogranariea sp. nov., isolated from wild Drosophila melanogaster

Abstract

Multiple isolates of the genus Providencia were obtained from the haemolymph of wild-caught Drosophila melanogaster fruit flies. Sixteen isolates were distinguished from the six previously described species based on 16S rRNA gene sequences. These isolates belonged to two distinct groups, which we propose each comprise previously undescribed species. Two isolates, designated A(T) and B(T), were characterized by DNA sequences of the fusA, lepA, leuS, gyrB and ileS housekeeping genes, whole-genome DNA-DNA hybridizations with their nearest relatives and utilization of substrates for metabolism. The closest phylogenetic relatives of strain A(T) are strain B(T) (86.9 % identity for the housekeeping genes) and Providencia stuartii DSM 4539(T) (86.0 % identity). The closest phylogenetic relatives of strain B(T) are strain A(T) (86.9 % identity) and P. stuartii DSM 4539(T) (86.6 % identity). The type strains of described species in this genus shared between 84.1 and 90.1 % identity for these sequences. DNA-DNA hybridization between the strain pairs A(T)-B(T), A(T)-P. stuartii DSM 4539(T) and B(T)-P. stuartii DSM 4539(T) all resulted in less than 25 % relatedness. In addition, patterns of utilization of amygdalin, arbutin, aesculin, salicin, d-sorbitol, trehalose, inositol, d-adonitol and d-galactose distinguish strains A(T) and B(T) from other members of this genus. Strains A(T) and B(T) therefore represent novel species, for which the names Providencia sneebia sp. nov. (type strain A(T) =DSM 19967(T) =ATCC BAA-1589(T)) and Providencia burhodogranariea sp. nov. (type strain B(T) =DSM 19968(T) =ATCC BAA-1590(T)) are proposed.