Prauserella muralis sp. nov., from the indoor environment

Abstract

A novel Gram-stain-positive, mycelium-forming actinobacterium (05-Be-005T) isolated from the wall of an indoor environment was studied for its taxonomic position. The isolated strain formed a substrate mycelium that fragmented into rod-shaped cells and showed an aerial mycelium on medium M79. On the basis of 16S rRNA gene sequence similarity studies, strain 05-Be-005T was shown to belong to the genus Prauserella, closely related to Prauserella rugosa DSM 43194T (96.6?% similarity), Prauserella alba YIM 90005T (95.9%) and Prauserella halophila YIM 90001T (95.4%). The predominant menaquinone was MK-9(H4); whole-cell hydrolysates contained meso-diaminopimelic acid as the diagnostic diamino acid of the cell wall and arabinose and galactose as the main sugars. Mycolic acids were absent. The polar lipid profile consisted of the lipids diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylinositol, phosphatidylserine and an unknown phospholipid. Major fatty acids C16:0 iso, C16:0, C17:1?8c and C17:1?6c supported the affiliation of strain 05-Be-005T to the genus Prauserella. The results of physiological and biochemical tests allowed clear phenotypic differentiation of strain 05-Be-005T from the three known Prauserella species. Strain 05-Be-005T represents a novel Prauserella species, for which we propose the name Prauserella muralis sp. nov., with the type strain 05-Be-005T (=CCUG 57426T =NRRL B-24780T =CCM 7635T=DSM 45305T).