Evidence of multiple taxa within commercially available reference strains of Corynebacterium xerosis.
Attempts to identify coryneform isolates resembling Corynebacterium xerosis can lead clinical microbiologists to identification schemes with conflicting descriptions which result in confusing C. xerosis with Corynebacterium striatum. For the present study we purchased all available American Type Culture Collection and National Collection of Type Cultures reference cultures of C. xerosis (n = 10) and C. striatum (n = 4) and analyzed them as follows: (i) analysis of biochemical reactions in conventional tests and in the Rapid CORYNE system, (ii) whole-cell fatty acid analysis by using the gas-liquid chromatography research software of Microbial ID, Inc., and (iii) analysis of DNA homology in dot blot hybridizations. Three C. xerosis strains were indistinguishable from the C. striatum strains in whole-cell fatty acid analyses and DNA hybridizations and shared very similar biochemical reactions. The remaining seven strains of C. xerosis clustered into five groups on the basis of fatty acid patterns, DNA hybridizations, and biochemical tests. No reference strain of C. striatum fit the species description in Bergey's Manual of Systematic Bacteriology. The type strains of both C. striatum and C. xerosis fit their respective descriptions by the Centers for Disease Control and Prevention. This study suggests that the 10 commercially available reference strains of C. xerosis represent six different taxa which should be assigned to new species.
Coyle
M B
MB
Department of Laboratory Medicine, Harborview Medical Center, University of Washington, Seattle 98104.
Leonard
R B
RB
Nowowiejski
D J
DJ
Malekniazi
A
A
Finn
D J
DJ
D015373:Bacterial Typing Techniques; D003352:Corynebacterium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D003354:Corynebacterium Infections / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D006801:Humans; D009693:Nucleic Acid Hybridization; D009894:Opportunistic Infections / Q000382:microbiology; D012015:Reference Standards; D013045:Species Specificity
D004269:DNA, Bacterial; D005227:Fatty Acids