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Biomedical subjects

S S Socransky

Publications and source records attributed to S S Socransky.

At least 91 records · Page 5Linked to original sources
PubMed1993

Characterization of hemolytic bacteria in subgingival plaque.

Three-quarters of the patients with periodontal diseases surveyed in this study had one or more distinct types of hemolytic bacteria in their subgingival plaque. Twelve different species of bacteria were identified, belonging to five genera (Actinomyces, Streptococcus, Staphylococcus, Prevotella, and Actinobacillus). Nine hemolytic isolates, consisting of four Prevotella denticola strains, two Actinomyces naeslundii genospecies 2 strains, and one each of P. melaninogenica, Streptococcus constellatus, and A. naeslundii genospecies 1 strains were characterized. Incorporation of pronase into blood agar medium inhibited hemolysis by all of the isolates, suggesting a proteinaceous component for each of their hemolysins. With one exception, hemolysin production appeared to be regulated by the concentration of environmental iron: exogenous hemin was found to inhibit hemolysin production, and the iron scavenging compound, 2,2'- dipyridyl, was found to promote hemolysin production by all of the strains except for the S. constellatus isolate. Genomic libraries of each of the hemolytic plaque isolates were prepared in Escherichia coli using pBR322. Hemolytic clones were isolated on blood agar medium containing ampicillin at frequencies ranging from 1-6.7 x 10(-4). Extensive restriction mapping revealed regions of homology in the case of clones derived from three P. denticola strains isolated from the same subjects. Two of the P. denticola-derived clones were virtually identical throughout the entrety of their > 5 Kb inserts. The clone derived from the third strain showed good homology to the other two within a 1.3 Kb region, but the flanking DNA showed no homology even though all three P. denticola isolates were shown to be clonally related by ribotyping.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinomyces↗
PubMed1993

Effect of therapy on periodontal infections.

Periodontal disease progression requires the simultaneous presence of high numbers of pathogens, low numbers of compatible or beneficial species, a conductive local environment, and a susceptible host. Effective therapy acts by altering one or more of these factors. Data from an ongoing study were used to examine the biological basis of treatment success or failure. Seventeen subjects showing disease progression were treated by Widman flap surgery at deep sites, scaling at shallow sites, and 1 of 4 randomly-assigned, systemically-administered adjunctive agents including amoxicillin/clavulanate potassium (Au) (n = 3), ibuprofen (n = 3), tetracycline (n = 9), or a placebo (n = 2). Clinical measurements and microbiological samples (enumerated using DNA probes) taken from the mesial aspect of each tooth pre-treatment and 12 months post-treatment were compared and 418 pre- and 418 post-therapy plaque samples were enumerated. Overall, the 4 treatments resulted in pocket depth reduction and "gain" in attachment. After therapy, the percentage of sites colonized by Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Bacteroides forsythus was decreased and counts > 10(6) were less frequent. Large attachment level gains were accompanied by major decreases in these species and were more frequent in subjects receiving antibiotics. A small number of sites in each treatment group became deeper and/or lost attachment. More than half of these sites were detected in 2 subjects who were older (65 vs. 44), had higher serum antibody to Actinobacillus actinomycetemcomitans serotype a (506 vs. 125 ELISA units), A. actinomycetemcomitans serotype b (518 vs. 130), and Campylobacter rectus (39 vs. 18).(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Infections↗
PubMed1992

Enumeration of subgingival species on primary isolation plates using colony lifts.

This study evaluated the feasibility of using a colony lift method and DNA probes to enumerate bacterial species cultured on primary isolation plates. Fourteen digoxigenin-labeled whole chromosomal DNA probes representing 12 subgingival species were validated by hybridization with colony lifts prepared from 249 reference strains of 51 species grown on Trypticase soy agar plates supplemented with 5% sheep blood. Colonies of reference strains were lifted onto Nytran filters from plates and treated to lyse cells, remove cellular proteins, denature and fix microbial DNA to the filters. Positive reactions were detected with an anti-digoxigenin antibody conjugated to alkaline phosphatase and revealed by bromo-chloro-indolyl phosphate and nitroblue tetrazolium. Cross-reactions were not observed for 13/14 probes, but 2 strains of Streptococcus mitis reacted with the probe to Streptococcus sanguis II. Subgingival plaque samples were taken by means of a sterile curette from mesiobuccal surfaces of teeth present in each of 26 subjects with differing periodontal disease states. Samples were dispersed, diluted, plated and incubated anaerobically for 7 d at 35 degrees C. Colonies were lifted as described above. Filters were cut into sections and hybridized with the 14 digoxigenin-labeled DNA probes. The probes were used to enumerate the test species and the total number of isolates was determined in 711 plaque samples. The colony lift method and DNA probes provided a sensitive, economical and quantitative method for enumerating cultivable microbial species in subgingival plaque samples. In addition, the amplification provided by growing the organisms on agar plates facilitated determination of numbers of organisms in small plaque samples, such as those from healthy sites.

Actinomyces↗
PubMed1992

Effect of sampling strategy on the false-negative rate for detection of selected subgingival species.

Subgingival plaque samples were obtained from the mesial surface of each tooth (maximum 28 samples per subject) in 62 subjects with prior evidence of destructive periodontal disease. The resulting 1596 samples were evaluated for their content of 14 selected taxa using a colony lift method and DNA probes. The present investigation compared the ability of 6 sampling strategies to detect a species known to be present in a subject as determined by the 28-site sampling procedure. On average, a species was not detected in 68% of the positive subjects if only the upper right first molar was sampled; 55% of subjects if both upper first molars were sampled; 36% of subjects if the 4 first molars were sampled; 28% of subjects if the 6 Ramfjord teeth were sampled; 60% of subjects if the deepest pocket was sampled and 25% of subjects if the 4 deepest pockets were sampled. The error rate was greatest for species that were infrequently detected in plaque samples such as Actinobacillus actinomycetemcomitans serotype b. This species was not detected in 49% of positive subjects, when the 6 Ramfjord teeth were sampled and 38% of subjects when the 4 deepest pockets were sampled. The data indicated that multiple plaque samples are needed to minimize false-negative rates.

Adolescent↗
PubMed1992

The use of DNA probes to examine the distribution of subgingival species in subjects with different levels of periodontal destruction.

The present investigation examined the distribution of 14 subgingival species at a total of 2299 sites in 90 subjects with different levels of periodontal destruction. Subgingival plaque samples taken from the mesial aspect of each tooth were anaerobically dispersed, diluted and plated on non selective media. After anaerobic incubation, colonies were lifted to nylon filters and specific species detected using digoxygenin-labeled whole chromosomal DNA probes. The mean total viable count for all sites in all subjects was 8.3 x 10(6). The probes accounted for an average of 27.8% of the total viable count. The % of subjects in which each species was detected was as follows; V. parvula, 98; B. intermedius I, 98; S. sanguis II, 96; B. intermedius II, 95; C. ochracea, 94; B. gingivalis, 91; S. sanguis I, 85; W. recta, 83; F. nucleatum ss. vincentii, 82; S. intermedius, 80; B. forsythus, 76; P. micros, 74; A. actinomycetemcomitans serotype a, 62 and A. actinomycetemcomitans serotype b, 52. The % of sites colonized by each of the 14 test species varied considerably within different subjects. The median number of sites colonized by different species ranged from 3.6% for A. actinomycetemcomitans serotype b to 43.5% for V. parvula. In half the subjects, the mean % of the total viable counts for each of the test species was less than 4%. When subjects were divided on the basis of % of sites at baseline with greater than 3 mm attachment loss, the 14 probes accounted for 29.9% of the microbiota in the localized disease group and 25% in the widespread disease group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Subgingival temperature (I). Relation to baseline clinical parameters.

44 subjects ranging in age from 14-71 years were measured at 6 sites per tooth for gingival redness, plaque accumulation, suppuration, bleeding on probing, pocket depth and attachment level. Subgingival temperatures were measured at the same 6 sites per tooth using a periodontal temperature probe (Periotemp, Abiodent, Danvers, MA). This instrument was also used to measure each subject's sublingual temperature in order to compute the differences between sublingual and subgingival temperature. Relationships were sought between the baseline clinical parameters and the temperature variables in subjects and at sites. The mean and standard deviation of the sublingual temperatures for the 44 subjects was 36.6 +/- 0.4 degrees C (range 35.8-37.6 degrees C). The mean of each subject's mean whole mouth subgingival temperature was 1.9 degrees C lower, 34.8 +/- 0.6 degrees C (range 33.4-36.1 degrees C). The differences of the mean subgingival temperature from sublingual ranged from -0.8 to -3.2 degrees C (average -1.9 +/- 0.5 degrees C). Mean temperature difference for a subject correlated with % of sites with plaque (rs = 0.45), redness (rs = 0.33), bleeding on probing (rs = 0.44), % of sites with attachment level greater than 3 mm (rs = 0.44), mean pocket depth (rs = 0.44) and mean attachment level (rs = 0.39). There were higher mean temperatures at sites exhibiting or not exhibiting plaque (35.0, 34.5 degrees C), redness (34.9, 34.6), bleeding on probing (35.1, 34.7) and suppuration (35.4, 34.8). Sites with pockets less than 4, 4-6 and greater than 6 mm had mean temperatures of 34.6, 35.2, 35.8 degrees C, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Subgingival temperature (II). Relation to future periodontal attachment loss.

The purpose of the present investigation was to determine whether subgingival temperature was a risk indicator of periodontal attachment loss (detected in the following 2 months) in a subject or at a site. 29 subjects were measured at 6 sites per tooth for clinical parameters as well as subgingival temperature using a periodontal temperature probe (Periotemp, ABIO-DENT, Danvers, MA). The same instrument was used to measure sublingual temperature in order to compute differences between subgingival and sublingual temperature. Clinical and temperature parameters were measured at 2-month intervals. A total of 49 subject visits which had both baseline temperature and subsequent attachment level change measurements were available for analysis. Attachment level loss greater than 2.5 mm occurred at 1 or more sites at 16 of 49 subject visits. Elevated mean subgingival temperature was related to subsequent attachment loss particularly in individuals who exhibited more than 1 progressing site. The odds ratios of a subject exhibiting new attachment loss at 1 or more sites or at 2 or more sites were 14.5 and 64.0 if the subject's mean subgingival temperature exceeded 35.5 degrees C. Subjects with high mean subgingival temperatures and widespread periodontal destruction appeared to be at greatest risk for new attachment loss. Discriminant analysis using % of sites with suppuration, redness and attachment level greater than 3 mm and mean site temperature correctly "predicted" disease activity with a sensitivity, specificity and overall agreement of 0.75, 0.76 and 0.82 respectively. Of 7243 sites, 43 (0.59%) and 160 (2.2%) showed attachment loss of either 2.5 mm or more or 2 mm or more respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Subgingival temperature (III). Relation to microbial counts.

The present investigation examined the relationship of selected bacterial species and subgingival temperature. 35 subjects were measured at 6 sites per tooth for clinical parameters and subgingival temperature. Measurements were repeated for 21 subjects at 2 month intervals providing a total of 66 subjects visits. At each visit, subgingival plaque samples were taken from the mesial aspect of each tooth and anaerobically dispersed, diluted and plated on non-selective media. After anaerobic incubation, colonies were lifted to nylon filters and specific species detected using digoxigenin-labeled whole chromosomal DNA probes. Species enumerated were; A. actinomycetemcomitans serotypes a and b, B. forsythus, B. gingivalis, B. intermedius I and II, C. ochracea, F. nucleatum ss. vincentii, P. micros, S. intermedius, S. sanguis I and II, V. parvula and W. recta. Total viable counts and counts of Capnocytophaga sp. were determined directly from the primary isolation plates. A total of 1581 samples were evaluated. Subject visits with higher mean subgingival temperatures had significantly higher mean %s of B. intermedius I and P. micros, and lower mean %s of Capnocytophaga sp. Sites with higher subgingival temperatures had elevated proportions of B. intermedius I and II, A. actinomycetemcomitans serotype a and B. gingivalis more frequently than sites with lower temperatures, while Capnocytophaga sp. were elevated more often at cooler sites. 43 of the subject visits had follow up attachment level measurements at 2 months. The 1026 microbial samples and the subgingival temperature measurements from these visits were related to longitudinal attachment change.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Longitudinal monitoring of humoral antibody in subjects with destructive periodontal diseases.

Fifty-one subjects (16-61 years old) with evidence of prior destructive periodontal disease were monitored clinically and immunologically at bi-monthly intervals for up to 5 yr. Periodontal disease activity, determined as new attachment loss, was detected in 33 of these subjects. Only 4 of 51 subjects failed to show an elevated serum antibody level to any of the 18 subgingival species tested. The antibody level threshold established for periodontally healthy subjects was exceeded most often in diseased subjects with serum antibody to Actinobacillus sp., P. gingivalis, E. corrodens, C. concisus, F. nucleatum and P. intermedia in that order. In general, most serum antibody levels to subgingival species remained relatively consistent for periods as long as 5 yr. However, major increases and decreases in antibody could be detected to at most one or two species in individual subjects. In addition, prolonged, steady increases and decreases in antibody to specific species could be detected in certain subjects. These findings suggest that major changes occurring in serum antibody may reflect fluctuations in the nature of the infection. Differences were observed in the antibody level to specific species when subjects were divided into subsets on the basis of clinical criteria. These included high levels of antibody to A. actinomycetemcomitans Y4 in LJP and RPP subjects and to A. actinomycetemcomitans 29523 in LJP and GJP subjects.

Adolescent↗
PubMed1992

The bacterial etiology of destructive periodontal disease: current concepts.

The interpretation of diagnostic tests for the detection of subgingival bacterial species is dependent on knowledge of the microbial etiology of destructive periodontal diseases. Specific etiologic agents of these diseases have been sought for over 100 years; however, the complexity of the microbiota, an incomplete understanding of the biology of periodontal diseases, and technical problems have handicapped this search. Nonetheless, a number of possible pathogens have been suggested on the basis of their association with disease, animal pathogenicity, and virulence factors. The immunological response of the host to a species and the relation of successful therapy to the elimination of the species have also been used to support or refute suspected periodontal pathogens. Current data suggest that pathogens are necessary but not sufficient for disease activity to occur. Factors which influence activity include susceptibility of the individual host and the presence of interacting bacterial species which facilitate or impede disease progression. Recent studies have attempted to distinguish virulent and avirulent clonal types of suspected pathogenic species and seek transmission of genetic elements needed for pathogenic species to cause disease. Finally, the local environment of the periodontal pocket may be important in the regulation of expression of virulence factors by pathogenic species. Thus, in order that disease result from a pathogen, 1) it must be a virulent clonal type; 2) it must possess the chromosomal and extra-chromosomal genetic factors to initiate disease; 3) the host must be susceptible to this pathogen; 4) the pathogen must be in numbers sufficient to exceed the threshold for that host; 5) it must be located at the right place; 6) other bacterial species must foster, or at least not inhibit, the process; and 7) the local environment must be one which is conducive to the expression of the species' virulence properties.

Bacteria↗
PubMed1991

Relation of baseline microbial parameters to future periodontal attachment loss.

The relationship between the level of subgingival species at baseline and subsequent attachment loss in a subject was examined. 38 subjects (14-71 years) with prior evidence of periodontal destruction were monitored 2x for pocket depth and attachment level at 6 sites per tooth at baseline and 2 months. A subject was considered to exhibit new attachment loss if 1 or more sites increased 3 mm or more in attachment level in 2 months. Subgingival plaque samples were taken at the baseline visit from the mesial aspect of each tooth (28 sites) using Gracey curettes. Samples were dispersed, diluted and plated on Trypticase soy agar supplemented with 5% sheep blood. After 7 days of anaerobic incubation, the colonies were lifted onto nylon filters, lysed and the DNA fixed to the filters. Digoxygenin-labeled DNA probes were used to enumerate 14 subgingival species. 17 of 38 subjects (44.7%) exhibited new attachment loss in 2 months. The % of the total viable count of each species was averaged for each subject. The species enumerated and the mean % of the total cultivable microbiota averaged across the active and inactive subjects were as follows; B gingivalis 2.3, 1.2; W. recta 1.3, 0.6; B. intermedius I 2.5, 2.0; B. forsythus 1.5, 1.2; A. actinomycetemcomitans serotype a 1.1, 0.8; F. nucleatum ss vincentii 1.1, 1.0; S. intermedius 2.0, 1.9; P. micros 1.5, 1.5; B. intermedius II 1.6, 1.7; A. actinomycetemcomitans serotype b 0.4, 0.6; S. sanguis I 1.8, 2.1; S. sanguis II 2.7, 3.0; V. parvula 3.9, 4.2; C. ochracea 0.9, 1.8.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Relation of counts of microbial species to clinical status at the sampled site.

The purpose of the present investigation was to relate clinical characteristics at a site to the frequency of detection, absolute counts and proportions of 14 subgingival species. Subgingival plaque samples were removed by curette from the mesial surface of 2299 teeth in 3 healthy and 87 subjects with periodontal attachment loss. Samples were dispersed, diluted and plated on Trypticase soy agar supplemented with 5% sheep blood. After 7 days of anaerobic incubation, colonies were lifted onto nylon filters, lysed and the DNA fixed to the filters. Digoxygenin-labeled DNA probes were used to identify colonies of each test species. Measurements of pocket depth, attachment level, recession, redness, bleeding on probing and suppuration were made at each sampled site. Total viable counts at sites ranged from 10(3) to greater than 10(8) and were strongly related to pocket depth. Mean total counts at sites less than 3 mm averaged 4.6 x 10(6), while mean counts at sites greater than 7 mm averaged 2.0 x 10(7). Species enumerated and % of sites colonized were as follows; V. parvula 44; S. sanguis II 36; B. intermedius I 33; C. ochracea 31; B. intermedius II 30; S. sanguis I 29; B. gingivalis 27; S. intermedius 25; P. micros 24; W. recta 23; F. nucleatum ss vincentii 18; B. forsythus 15; A. actinomycetemcomitans serotype a 10; A. actinomycetemcomitans serotype b 8. Counts of B. intermedius II were higher at sites which exhibited gingival redness while B. intermedius I was higher at sites which bled on probing. A. actinomycetemcomitans serotype b was more frequent and at higher mean % at sites without recession. The opposite was true for S. sanguis II. B. gingivalis was somewhat more prevalent and at higher levels at suppurating sites. B. gingivalis, B. intermedius I and II and B. forsythus were found more frequently and at higher levels at sites with deeper pockets, while V. parvula was less prevalent at sites with pocket depths less than 4 mm. B. gingivalis, B. intermedius I and A. actinomycetemcomitans serotype b increased with increasing pocket depth in both localized and widespread disease subjects, but mean counts were higher in the localized disease subjects at any pocket depth. Only W. recta was found at higher levels at deep sites in widespread disease subjects when compared with similar sites in localized disease subjects. No suspected pathogens were detected in 38% of shallow sites, 31% of intermediate sites and 22% of deep sites, 2/3 of deep pockets, but less than 1/2 of shallow pockets harbored at least 2 of the suspected pathogens.

Aggregatibacter actinomycetemcomitans↗
PubMed1991

Levels of interleukin 1 beta in tissue from sites of active periodontal disease.

Interleukin 1 beta is a potent bone resorptive cytokine which also mediates soft tissue destruction through the stimulation of prostaglandin production, and the induction of collagenase and other proteases. This constellation of activities suggests a role for IL-1 beta in the pathogenesis of human periodontitis. Levels of IL-1 beta were therefore determined in tissue obtained from (1) diseased, active (2) diseased, inactive and (3) healthy sites from 12 patients with destructive adult periodontitis. Disease activity was defined as attachment loss of greater than or equal to 2.5 mm, as determined by sequential probing and the tolerance method. IL-1 beta was extracted from homogenates of tissue biopsies taken at surgery, and levels were quantified by ELISA. IL-1 beta was found to be present in most patient tissue samples, with levels ranging from 0-82 ng/ml. Disease active sites had higher IL-1 beta levels (p less than 0.05) than inactive and healthy sites. Diseased inactive sites were divided into 2 groups, those losing small amounts of attachment (0.5-2.0 mm, worsening sites) and those which showed no change or attachment gain (stable sites). Stable diseased sites had IL-1 beta levels which were comparable to those found in healthy sites, and which were significantly different from active sites (p less than 0.02). Worsening sites had IL-1 beta levels intermediate between the levels in stable and active sites. Detection of disease activity occurred more frequently at sites with IL-1 beta levels greater than 25 ng/ml (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Clinical risk indicators for periodontal attachment loss.

The purpose of the present investigation was to evaluate the association of baseline clinical parameters of periodontal disease with disease progression in the following year. 271 randomly selected subjects from Ushiku Japan were monitored for overt gingivitis and plaque accumulation at 4 sites per tooth and probing pocket depth, probing attachment level and bleeding on probing at 6 sites per tooth for all teeth at baseline and 1 year. A subject was considered to exhibit additional attachment loss if one or more sites increased 3 mm or more in a probing attachment level measurement in one year. The clinical variables included age, sex, number of missing teeth, mean pocket depth and attachment level. In addition, the % of sites which exhibited overt gingivitis, visible plaque, pocket depths, attachment levels or gingival recession over certain mm thresholds or bled on probing were determined. Chi 2 analysis was used to seek significant associations between the baseline clinical variables and subsequent attachment loss in a subject. Only 74 of the 271 subjects (27.3%) exhibited additional attachment loss of 3 mm or more at 1 or more sites after 1 year. Older subjects had a greater risk of disease progression than younger subjects. There were no significant differences in % of individuals exhibiting additional attachment loss when divided on the basis of sex, number of missing teeth or % of sites with overt gingivitis. However, the greater the % of sites with visible plaque or which bled on probing, the greater was the likelihood of subsequent attachment loss. Increasing mean levels of pocket depth or attachment level or increasing %s of sites exhibiting prior attachment loss were strongly related to the proportion of individuals with subsequent attachment loss. Gingival recession exhibited similar but weaker relationships. Log-linear analysis suggested that the association between bleeding on probing, age, or plaque levels with additional attachment loss may be explained by the association of these variables with baseline attachment loss. The analyses were repeated with a positive subject defined as having only 1 active site or 2 or more active sites. 37 subjects fit the 1st criterion and the remaining 37 the 2nd criterion. The associations observed were almost identical to those found when subjects were considered positive on the basis of 1 or more changing sites. Discriminant analysis was used to classify subjects as active or inactive using up to 11 predictor variables.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Tissue levels of bone resorptive cytokines in periodontal disease.

The levels of 3 bone resorptive cytokines, interleukin 1 alpha (IL-1 alpha), IL-1 beta, and tumor necrosis factor alpha (TNF alpha), were assessed in tissues from sites of periodontal disease. As determined by ELISA of tissue extracts, IL-1 beta and TNF alpha were detected in all diseased sites, whereas IL-1 alpha was present in 8/22 sites, IL-1 beta was present in highest concentration (mean +/- SEM: 11,695 +/- 2,888 pg/ml; 672 pM), followed by TNF alpha (434 +/- 135 pg/ml; 26 pM), and IL-1 alpha (342 +/- 160 pg/ml; 20 pM). The levels of all 3 mediators were significantly lower in clinically healthy tissues. There was a highly significant correlation between levels of IL-1 beta and TNF alpha (rs = 0.61, P less than 0.001), suggesting coordinated expression of these 2 mediators. The numbers of cells containing each mediator was also determined by indirect immunofluorescence on frozen tissue sections. Consistent with findings from tissue extracts, IL-1 beta-containing cells were present in approximately 5-fold higher numbers than TNF alpha-containing cells, and 40-fold higher numbers than IL-1-alpha-containing cells. Taken together with previous findings, these results indicate that IL-1 beta is likely to be an important mediator in the pathogenesis of periodontal disease.

Adult↗
PubMed1990

Proposal of three subspecies of Fusobacterium nucleatum Knorr 1922: Fusobacterium nucleatum subsp. nucleatum subsp. nov., comb. nov.; Fusobacterium nucleatum subsp. polymorphum subsp. nov., nom. rev., comb. nov.; and Fusobacterium nucleatum subsp. vincentii subsp. nov., nom. rev., comb. nov.

Heterogeneity among isolates of Fusobacterium nucleatum has been recognized for many years. The phenotypic properties of 340 strains considered to be F. nucleatum were examined. While these strains were phenotypically similar and fit the description of F. nucleatum, they could be differentiated into three groups on the basis of electrophoretic patterns of whole-cell proteins and DNA homology. Strains in groups I and II showed greater than 80% DNA homology within groups and less than 75% similarity between groups. Strains of group III demonstrated greater than 85% DNA homology to each other and less than 65% similarity to strains in groups I and II. We propose that Fusobacterium nucleatum be divided into the following three subspecies: Fusobacterium nucleatum subsp. nucleatum, with type strain ATCC 25586; Fusobacterium nucleatum subsp. polymorphum, with type strain ATCC 10953; and Fusobacterium nucleatum subsp. vincentii, with type strain ATCC 49256.

Bacterial Proteins↗