Abstract
Phylogenetic analysis of the genera within the suborder Pseudonocardineae based on almost complete sequences of 16S rDNA showed that Saccharothrix cryophilis NRRL B-16238(T) was misplaced within the genus Saccharothrix. Saccharothrix cryophilis NRRL B-16238(T) appeared to be phylogenetically closest to Streptoalloteichus, but is morphologically distinct from this genus because sporangia with motile spores are not observed. The aerial mycelium fragments into rod-shaped elements and sclerotium-like bodies are observed occasionally in the substrate mycelium. The cell wall contains meso-diaminopimelic acid, whole-cell hydrolysates contain galactose, rhamnose and ribose, the phospholipid pattern is type PIV and the principal menaquinone is MK-9(H(4)). A new genus to accommodate Saccharothrix cryophilis is proposed, Crossiella gen. nov., in recognition of the contributions of Thomas Cross, a distinguished actinomycete biologist at the University of Bradford, UK. The type species is Crossiella cryophila gen. nov., comb. nov.