Corynebacterium matruchotii has been the subject of numerous dental pathogenesis studies. The purpose of the present study was to resolve concerns about diversity within the reference strains of C. Analysis of whole-cell fatty acid profiles with the library generation software of Microbial ID Inc. These three groups of organisms were also distinguishable by DNA-DNA dot blot hybridization, by sequences of two hypervariable regions of the 16S rRNA gene, and by the pyrrolidonyl arylamidase test.
|Published (Last):||4 October 2004|
|PDF File Size:||8.41 Mb|
|ePub File Size:||13.24 Mb|
|Price:||Free* [*Free Regsitration Required]|
Corynebacterium matruchotii has been the subject of numerous dental pathogenesis studies. The purpose of the present study was to resolve concerns about diversity within the reference strains of C.
Analysis of whole-cell fatty acid profiles with the library generation software of Microbial ID Inc. These three groups of organisms were also distinguishable by DNA-DNA dot blot hybridization, by sequences of two hypervariable regions of the 16S rRNA gene, and by the pyrrolidonyl arylamidase test. These studies indicate that two C. The colonial morphology and biochemical reactions of the C. Strain ATCC is unique and represents a novel species.
The seminal paper by Gilmour et al. Based on chemotaxonomic characteristics, Bacterionema matruchotii was assigned to the genus Corynebacterium by Collins et al. Since the database included most other recognized Corynebacterium species of human origin, we suspected that the developers had encountered some unresolvable discrepancies with representative strains of this species. To explore this possibility, we purchased all strains of C.
Because a large body of work has been published on the possible role of C. The present study was designed to examine the taxonomic relatedness of commercially available and other reference strains of C. The question was addressed on the basis of whole-cell fatty acid analyses, DNA-DNA dot blot hybridizations, sequencing of two hypervariable regions of the 16S rRNA gene, and biochemical reactions. Takazoe, Tokyo, Japan. Bernard, were also studied because they are similar to the C.
Louis, Mo. Conventional biochemical tests were done as described by Krech and Hollis 18 , including enteric fermentation media with Andrade indicator. As previously described by Gavin et al. For confirmation of h results, the carbohydrate reactions in the strip also were read after incubation for 48 h. API profile numbers were referenced to the version 2 database. Whole-cell fatty acid analyses were performed as previously described 7. The organisms were grown on TSBA. MIDI system, and data were analyzed with the library generation software of MIDI, which is a program that provides two-dimensional cluster plots as well as dendrograms based on cluster analysis.
The two-dimensional plots were based on principal component analysis. Principal Component 1 is the component responsible for the greatest degree of variability among the samples tested and is represented on the horizontal axis.
Principal Component 2 is responsible for the second greatest degree of variability and is displayed on the vertical axis. The scale for both axes is the Euclidean distance.
The DNA extraction procedure was described previously 6. In order to select hypervariable regions likely to be unique for each taxon, the 16S rRNA gene sequences in nine Corynebacterium species were compared using the Baylor College of Medicine search launcher ClustalW version 1.
Two regions of over 40 bp in length were chosen and termed hypervariable region 1, corresponding to Escherichia coli 16S rRNA positions to , and hypervariable region 2, corresponding to positions to After amplification, mineral oil was removed by the addition of chloroform J.
Baker, Phillipsburg, N. Microcon microconcentrators Amicon, Inc. Fatty acid profiles of all strains were analyzed with the library generation software of MIDI, resulting in the two-dimensional plot shown in Fig. A dental clinical isolate of C. The major fatty acid peaks of the group A true C. The remaining fatty acids detected by the MIDI system not listed are believed to be the products of mycolic acid degradation, which occurs at the high temperature in the system's injection port Circles, group A C.
Data from repeat analyses are included. Numbers on the axes indicate the Euclidean distance. Representative lumigraphs of DNA dot blots for 11 of the 12 strains in this study are shown in Fig. The DNA dot blot results were in complete agreement with the groupings indicated by the MIDI cluster analysis from cellular fatty acid profiles.
Probe and target DNAs are indicated. For four of the five strains in group B, the sequences of the two variable regions were almost identical to that published for C.
Alignment of sequences of two variable regions in the 16S rRNA gene. GenBank sequences of C. Bold bases for C. The first and last nucleotides of regions 1 and 2 correspond to E. Four of the six true C. Colonies of strains ATCC and Richardson's 13 had a crinkled surface and lifted as a single dry colony when touched by a wire loop.
When grown in the presence of CO 2 , these two strains produced distinct pits in the agar. The C. When C. When grown in a CO 2 -enriched atmosphere, the C. Colonies of strain ATCC were pinpoint to 0. During the first 6 months of this study, the three taxa had distinct Gram stain morphologies that showed little variance with time and growth media.
The six true C. The five C. In an aerobic atmosphere the novel strain, ATCC , produced very short but relatively broad gram-positive rods in diphtheroid-like clusters.
In the presence of CO 2 , this strain produced pleomorphic rods in a variety of sizes. Following multiple serial subcultures during a 2-year period, the C. The Gram stain morphology of C. Arrows indicate whip handle morphology.
All the strains in this study grew better in 0. The greatest growth enhancement in 0. The production of pyrrolidonyl arylamidase was the only trait that consistently distinguished C.
The atypical strain, ATCC , was unique in its failure to reduce nitrate and its production of alkaline phosphatase. The conventional esculin test was negative for all strains, whereas it was positive in the CORYNE strip for 9 of the 12 strains. Two of the five C. With the exception of one isolate, repeat testing of C.
The group corresponding to the C. Gilmour and Turner described C. They described a rough-to-intermediate-to-smooth morphological variation. When our biochemical results are examined, it is apparent that the true C. The API system, which does not include C. Biochemical tests do not readily distinguish C.
This difference is consistent with two earlier studies that tested a total of 63 C. Within isolates from 58 cultures of healthy throats, von Graevenitz et al. Riegel et al. However, when we tested our C. Using the in-house peptone water fermentation broth with Andrade indicator that the Centers for Disease Control and Prevention recommends for testing coryneforms 18 , we did repeat tests with mannitol and galactose.
Two of the C. Four of the C. An additional study of these strains' reactions on both mannitol and galactose in peptone water broth from two providers revealed differences in the frequency of positive results data not shown. The differences in urease activity and esculin hydrolysis observed between the Rapid CORYNE system and conventional tests might be attributed to the different basal media in these two systems. It was surprising to find that our strains of C.
Our C. The differences between our strains and Riegel's strains of C. Furthermore, the original specimens for our strains and the Riegel strains were quite different. In contrast to the five C.
ATCC strains and were from a gingival margin and subgingival plaque, respectively, and LCDC strains and were isolated from blood and a foot abscess, respectively.
Within the true C. All but one of the C. However, the sequence of hypervariable region 1 in C. Because this strain was consistent with the species C.
The organism has provided valuable information regarding calcification of bioprostheses 17 , dental plaque 10 , and the principles of membrane-mediated proteolipid-dependent calcification in vertebrate systems 2. It is important to note that the diversity found in this study does not affect the conclusions of pathogenesis studies with C. We thank Marion N.
Corynebacterium matruchotii has been the subject of numerous dental pathogenesis studies. The purpose of the present study was to resolve concerns about diversity within the reference strains of C. Analysis of whole-cell fatty acid profiles with the library generation software of Microbial ID Inc. These three groups of organisms were also distinguishable by DNA-DNA dot blot hybridization, by sequences of two hypervariable regions of the 16S rRNA gene, and by the pyrrolidonyl arylamidase test. These studies indicate that two C.
Type strain:. Culture col. Note that changes will be reviewed and judged. If your changes are legitimate, changes will occur within the next Bac Dive update. Only proposed changes supported by the according reference will be reviewed. The Bac Dive team reserves the right to reject proposed changes.