Correspondence

A yellow-pigmented bacterial isolate, strain G1-2T, obtained from the surface of an air humidifier, was characterized taxonomically. 16S rRNAgene sequence analysis, physiological characterization and estimation of the ubiquinone and polar lipid patterns and fatty acid composition revealed that strain G1-2T was similar toSphingomonas yabuuchiae and Sphingomonas sanguinis, but also showed pronounced differences. On the basis of these results, a novel species of the genus Sphingomonas is described, for which the name Sphingomonas pseudosanguinis sp. nov. is proposed. The type strain is G1-2T (=CCUG 54232T=CIP 109431T). The genus Sphingomonas, proposed by Yabuuchi et al. (1990), contains Gram-negative, non-fermentative rods that are characterized chemotaxonomically by the presence of ubiquinone Q-10, sym-homospermidine as the key poly-amine, a lipid pattern consisting of phosphatidylethanol-amine (with the exception of Sphingomonas echinoides DSM 1805T; Denner et al., 1999), phosphatidylglycerol, diphosphatidylglycerol, sphingoglycolipid and phospha-tidylcholine as the major lipids and by the presence of 2-hydroxymyristic acid (2-OH 14: 0) and the absence of 3-hydroxy fatty acids in their fatty acid profiles (Busse et al.