Listeria in sheep water trough

In the context of a study on the occurrence of Listeria species in an animal farm environment in Valencia, Spain, six Listeria -like isolates could not be assigned to any known species.

Phylogenetic analysis based on the 16S rRNA gene and on 231 Listeria core genes grouped these isolates in a monophyletic clade within the genus Listeria , with highest similarity to Listeria thailandensis .

Whole-genome sequence analyses based on in silico DNA–DNA hybridization, the average nucleotide blast and the pairwise amino acid identities against all currently known Listeria species confirmed that these isolates constituted a new taxon within the genus Listeria . Phenotypically, these isolates differed from other Listeria species mainly by the production of acid from inositol, the absence of acidification in presence of methyl α-d-glucoside, and the absence of α-mannosidase and nitrate reductase activities.

The name Listeria valentina sp. nov. is proposed for this novel species, and the type strain is CLIP 2019/00642T (=CIP 111799T=DSM 110544T).

Listeria valentina sp. nov., isolated from a water trough and the faeces of healthy sheep

International Journal of Systematic and Evolutionary Microbiology

Juan J. Quereda1​Alexandre Leclercq2​,3Alexandra Moura2​,3​,4​Guillaume Vales2​,3​Ángel Gómez-Martín1​Ángel García-Muñoz1​Pierre Thouvenot2​,3​Nathalie Tessaud-Rita2​,3​Hélène Bracq-Dieye2​,3​Marc Lecuit2​,3​,4​,5​

https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.004494