Acinetobacter legionensis sp. nov. and Acinetobacter psychrotolerans sp. nov. isolated from different types of retail meat.

Twelve isolates representing two novel Acinetobacter species were isolated from various fresh meat and meat preparation samples collected from supermarkets in León, Spain. These isolates were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and GTDB-Tk software as members of the genus Acinetobacter. Phylogenomic analysis based on the core genome showed that these isolates formed two separate branches (1 including 11 isolates: ULE_I046T, ULE_I001, ULE_I024, ULE_I037, ULE_I053, ULE_I057, ULE_I064, ULE_I068, ULE_I075, ULE_I080 and ULE_I092; and the other only one, ULE_I010T) separated from all known Acinetobacter species. Average nucleotide identity and digital DNA-DNA hybridization values of all isolates with closely related type strains of species of the genus Acinetobacter supported their status as new species. The names Acinetobacter legionensis sp. nov. (comprising 11 isolates) and Acinetobacter psychrotolerans sp. nov. (comprising one strain) were proposed for the two novel taxa. Additional phylogenomic and phenotypic analyses showed that strain LMG 10606 (=RUH 2236), originally assigned to Acinetobacter guillouiae, belongs to A. legionensis sp. nov. Other two strains from the original description of A. guillouiae (LUH 5606 and LUH 6980) may also represent members of A. legionensis sp. nov., as indicated by a rpoB gene phylogenetic tree analysis. The phenotypic characteristics most useful for the differentiation of the novel species described in the present study from known Acinetobacter species were the assimilation of malonate and the inability to grow on histamine and phenylacetate of A. legionensis sp. nov., and the inability of A. psychrotolerans sp. nov. to grow over 30 °C. The type strain A. legionensis ULE_I046T (=CECT 31169T=CCP 535T) has a genome size of 4.58 Mb and a G+C content of 37.7 mol%. The type strain A. psychrotolerans ULE_I010T (=CECT 31168T=CCP 534T) has a genome size of 3.56 Mb, with a G+C content of 37.2 mol%.