Pseudarcicella hirudinis gen. nov., sp. nov., isolated from the skin of the medical leech Hirudo medicinalis

Abstract

A pinkish-pigmented, Gram-stain-negative, rod-shaped, non-spore-forming bacterium, strain E92(T), was isolated from the skin of the medical leech Hirudo medicinalis, on R2A agar. 16S rRNA gene sequence analysis of strain E92(T) showed a relatively low 16S rRNA gene sequence similarity (93.0-93.5 %) to representatives of the genus Arcicella and 91.5-92.0 % to members of the genus Flectobacillus. The polar lipid profile was composed of the major compounds phosphatidylethanolamine, an unidentified aminophospholipid, an unidentified aminolipid and an unidentified polar lipid; glycolipids were not detected. The major quinone was menquinone MK-7, and the major compound in the polyamine pattern was spermidine. The predominant fatty acids were C(16 : 1)ω5c and C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH (detected as summed feature 3). The isolate did not contain C(14 : 0) or the hydroxyl fatty acid iso-C(17 : 0) 3-OH found in all representatives of the genera Arcicella and Flectobacillus, but did produce C(18 : 1)ω7c and 11-methyl C(18 : 1)ω7c which are not found in these two genera. The DNA G+C content of strain E92(T) was 64.4 mol%. The unique 16S rRNA gene sequence, and specific chemotaxonomic and physiological data revealed that strain E92(T) represents a new genus in the family Cytophagaceae for which we propose the name Pseudarcicella hirudinis gen. nov., sp. nov., with the type strain of the type species as E92(T) (= LMG 26720(T) = CCM 7988(T)).