Acinetobacter silvestris sp. nov. discovered in forest ecosystems in Czechia (vol 72, 005383, 2022)

We investigated a taxonomically novel group of the genus Acinetobacter, which included five strains isolated from soil and water samples collected in preserved forest areas in Czechia between 2013 and 2021. The whole-genome sequences of the strains were 3.1-3.2 Mb in size, with G+C contents of 38.0-38.2mol%. Core genome-based phylogenetic analysis showed that they formed a compact and deeply branched Glade within the genus. The genomic average nucleotide identity based on BLAST/digital DNA-DNA hybridization values for the novel strains were 99.2-99.6%/95.2-98.4%, whereas those between the novel strains and the type strains of the known Acinetobacter species reached <78%/<24%. The results of the genus-wide analysis of whole-cell MALDI-TOF mass spectra supported the sharp distinctness of the group. The five strains were non-glucose acidifying. nonhaemolytic, nonproteolytic and growing at 28 degrees C. but not at 32 degrees C; they assimilated acetate, benzoate, ethanol, L-histidine, 4-hydroxybenzoate, DL-lactate and malonate but not 4-aminobutyrate, L-aspartate or 2,3-butanediol; this phenotype is unique among the known Acinetobacter species. We conclude that the five strains represent a novel environmental species, for which the name Acinetobacter silvestris sp. nov. is proposed, with the type strain ANC 4999(T) (=CCM 920(T)=CCUG 7587(T)=CNCTC 8124(T)).