Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2001
Publication Date: N/A
Interpretive Summary: Identification and classification of the filamentous bacteria, or actinomycetes, found in soil is difficult even though these microorganisms are important as producers of most medically and agriculturally important antibiotics. Determination of the sequence of the 16S ribosomal RNA gene provides extremely useful information for this purpose, and predicted that a new genus of actinomycete bacteria existed, to be called Lechevalieria in honor of Hubert and Mary Lechevalier, eminent American actinomycete biologists at the Waksman Institute of Microbiology at Rutgers University. The biochemical composition of strains predicted as members of this new genus based on molecular sequence data was also found to be unique and diagnostic. Certain sequence patterns in the 16S ribosomal RNA gene were found to serve as signatures or fingerprints for these actinomycetes and will be extremely useful for the rapid identification of new isolates from nature, particularly when searching for strains capable of producing new antibiotics or other useful products.
Technical Abstract: The genus Saccharothrix is phylogenetically heterogeneous based on analysis of almost complete 16S rDNA sequences. An evaluation of chemotaxonomic, morphological, and physiological properties in light of the molecular phylogeny data revealed that several species are mis- classified. Saccharothrix aerocolonigenes NRRL B-3298**T and Saccharothrix flava NRRL B-16131**T comprise a lineage distinct from Saccharothrix and separate from Lentzea. The genus Lechevalieria gen. nov. is proposed for these species with Lechevalieria aerocolonigenes comb. nov. as the type species, and S. flava is transferred as Lechevalieria flava comb. nov. Several of the chemotaxonomic characteristics observed for Lentzea albidocapillata DSM 44073**T were not in agreement with the original description of Lentzea Yassin et al. and the description is amended to include galactose, mannose, and traces of ribose as diagnostic whole cell sugars, MK-9(H4) as the principal menaquinone, and lack of tuberculostearic acid in the fatty acid profile. Saccharothrix waywayandensis NRRL B-16159**T, Saccharothrix aerocolonigenes NRRL B-16137, and 'Asiosporangium albidum' IFO 16102 are members of the amended genus Lentzea based on phylogenetic and chemotaxonomic properties. S. waywayandensis is transferred to Lentzea as Lentzea waywayandensis comb. nov., while the new species Lentzea californiensis sp. nov. and Lentzea albida sp. nov. are described for S. aerocolonigenes NRRL B-16137 and 'A. albidum' IFO 16102, respectively. Nucleotide signatures in the 16S rDNA sequences are defined that are diagnostic for the genera Lechevalieria, Lentzea, and Saccharothrix.