Mucilaginibacter frigoritolerans sp. nov., Mucilaginibacter lappiensis sp. nov. and Mucilaginibacter mallensis sp. nov., isolated from soil and lichen samples

Five cold-adapted bacteria belonging to the genus Mucilaginibacter were isolated from lichen and soil samples collected from Finnish Lapland and investigated in detail by phenotypic and phylogenetic analyses. Based on 16S rRNA gene phylogeny, the novel strains represent three new branches within the genus Mucilaginibacter. The strains were aerobic, chemo-organotrophic, non-motile rods and formed pigmented, smooth, mucoid colonies on solid media. The strains grew between 0 and 33 °C (optimum growth at 25 °C) and at pH 4.5-8.0 (optimum growth at pH 6.0). The main cellular fatty acids were iso-C(15 : 0), summed feature 3 (C(16 : 1)ω7c/iso-C(15 : 0) 2-OH) and iso-C(17 : 0) 3-OH and the major respiratory quinone was MK-7. The DNA G+C contents were 44.0-46.5 mol%. Based on phylogenetic, phenotypic and chemotaxonomic data, the strains represent three novel species of the genus Mucilaginibacter for which the names Mucilaginibacter frigoritolerans sp. nov. (type strain FT22(T) =ATCC BAA-1854(T) =LMG 25359(T)), Mucilaginibacter lappiensis sp. nov. (type strain ANJLI2(T) =ATCC BAA-1855(T) =LMG 25358(T)) and Mucilaginibacter mallensis sp. nov. (type strain MP1X4(T) =ATCC BAA-1856(T) =LMG 25360(T)) are proposed.