Descriptions of Prevotella tannerae sp. nov. and Prevotella enoeca sp. nov. from the human gingival crevice and emendation of the description of Prevotella zoogleoformans.

Prevotella tannerae sp. nov. and Prevotella enoeca sp. nov. from the human gingival crevice are described. These organisms are obligately anaerobic, non-spore-forming, nonmotile, gram-negative, rod-shaped bacteria that ferment carbohydrates and produce succinic and acetic acids. Bile inhibits growth. Some strains (38%) of P. tannerae produce colonies with a tan to black pigment when they are grown on rabbit blood agar. The type strains are P. tannerae ATCC 51259 and P. enoeca ATCC 51261. In addition, the description of Prevotella zoogleoformans is emended to exclude strains now recognized as members of Prevotella heparinolytica.

Oribaculum catoniae gen. nov., sp. nov.; Catonella morbi gen. nov., sp. nov.; Hallella seregens gen. nov., sp. nov.; Johnsonella ignava gen. nov., sp. nov.; and Dialister pneumosintes gen. nov., comb. nov., nom. rev., Anaerobic gram-negative bacilli from the human gingival crevice.

The following four new species of anaerobic gram-negative bacilli isolated from the human gingival crevice are described: Oribaculum catoniae, with ATCC 51270 as the type strain; Catonella morbi, with ATCC 51271 as the type strain; Hallella seregens, with ATCC 51272 as the type strain; and Johnsonella ignava, with ATCC 51276 as the type strain. C. morbi is associated with periodontitis. H. seregens and J. ignava are associated with gingivitis and periodontitis. O. catoniae has been isolated from healthy and diseased gingiva. Dialister pneumosintes (Olitsky and Gates 1921) gen. nov., comb. nov., nom. rev., associated with gingivitis, is proposed to accommodate organisms formerly classified as Bacteroides pneumosintes.

Comparative distribution and taxonomic value of cellular fatty acids in thirty-three genera of anaerobic gram-negative bacilli.

Cellular fatty acid profiles were determined for species in 33 genera of anaerobic gram-negative bacilli and were confirmed to be a useful taxonomic tool. Most of the genera could be differentiated by visual inspection of their profiles. The three genus pairs that were most difficult to distinguish visually (Bacteroides and Prevotella, Pectinatus and Megamonas, and Serpulina and Bilophila) and the species of these genera were differentiated by the MIDI (Microbial ID, Inc.) identification system. Similarities in cellular fatty acid profiles may be correlated with similarities in other phenotypic characteristics, but more often there is no other obvious phenotypic relationship. Although medium components may not change the constituents detected or the ratios among the constituents detected for some species, identical medium changes may result in vast differences in the profiles obtained with other species. Thus, if a worker wishes to compare profiles of various taxa, it is essential that the same cultural and analytical conditions be used.

Investigation of the influences of puberty, genetics, and environment on the composition of subgingival periodontal floras.

The classical twin model was utilized in this study in an attempt to determine the importance of host genetics to the composition of the subgingival flora. Simultaneously, the effect of puberty on the flora composition was assessed. The compositions of the floras were significantly different at ages 11 and 14 in the same people, indicating that transition to an adult flora composition may be initiated during puberty. However, the numbers of subjects who had prepubertal and postpubertal testosterone levels in this study were too small to demonstrate significant differences based solely on testosterone level (P = 0.053 and 0.11 for tests of unrelated members, i.e., all twins "a," the first twin of each pair, and all twins "b," the second twin of each pair). Sixteen unrelated 11-year-old subjects had prepubertal levels of less than 30 ng of testosterone per dl of serum, and only six of these unrelated subjects had levels above 300 ng/dl by age 14. Of their twin siblings, who formed the second group of unrelated individuals, 15 had prepubertal levels and only 5 reached postpubertal levels. Unpaired t tests indicated that Veillonella atypica, Prevotella denticola, and Prevotella melaninogenica were among the species that contributed most to changes in flora composition during puberty. The compositions of subgingival floras of 11-year-old monozygous and dizygous male twins were significantly more similar than those of unrelated subjects in the study (P = 0.004 and 0.009, respectively). At 12.5 years of age, the floras of monozygous twins remained more similar than those of unrelated subjects (P = 0.001), but the dizygous-twin floras were not significantly more similar than those of unrelated people. This difference corresponded with moderate and varied testosterone levels within dizygous-twin pairs at age 12.5. By age 14 both monozygous and dizygous twins again had floras with compositions more similar than those of unrelated people (P = 0.008 and 0.002, respectively). Estimates of the genetic contributions to the increased similarity of the floras of twins as compared with floras of unrelated people indicated that the concentrations of several species in the flora may be influenced by host genetic factors. The prevalence of certain other species appeared to be controlled primarily by environment.

The influence of race and gender on periodontal microflora.

Previous studies have demonstrated that demographic characteristics of subject populations influence both the incidence of periodontal diseases and various aspects of host responses to periodontal bacteria. In this study we analyzed the components of the subgingival microflora from individuals with adult periodontitis, early onset periodontitis, gingivitis, and periodontal health as a function of gender and race (black and white). Clinical categories were analyzed individually so that there were no differences in the clinical characteristics of the sampled sites. No significant differences were noted in the subgingival microflora between males and females. When either the first two bacterial samples from each subject or all bacterial samples taken from each subject were included in the analysis, it was found that Porphyromonas gingivalis was more significantly associated with black subjects in the adult periodontitis group. When all samples were considered in the analysis, it was found that Peptostreptococcus anaerobius was associated with black subjects in the adult periodontitis group, while Fusobacterium nucleatum was associated with white subjects in both the adult periodontitis and early onset periodontitis groups. Thus a limited number of important bacterial components of the subgingival microflora are influenced by the race and diagnosis of the subject group.

Periodontal microflora of HIV positive subjects with gingivitis or adult periodontitis.

The subgingival microflora of 39 HIV+ subjects with gingivitis or adult periodontitis was cultured quantitatively anaerobically for bacteria, spirochetes, and mycoplasma and aerobically for yeasts. Isolates were characterized by conventional biochemical tests, polyacrylamide gel electrophoresis of soluble proteins, cellular fatty acid profiles, immunofluorescence, and immunodiffusion. In general, the same types of bacteria were isolated from the subgingival crevice of HIV+ subjects as we previously had isolated from the subgingival crevice of non-HIV subjects. A statistically significant difference was found between the composition of the flora of HIV+ subjects with adult periodontitis (AP) and concurrent studies of a non-HIV+ AP population. Mycoplasma salivarium was significantly elevated in the HIV+ subjects examined. Yeasts were isolated from only 10% of the samples and from 13% of the HIV-positive subjects at 0.05 to 0.0002% of the total cultivable count when present.

Emended descriptions of Prevotella denticola, Prevotella loescheii, Prevotella veroralis, and Prevotella melaninogenica.

During studies of human periodontal disease, a number of bacterial strains were encountered that, on the basis of results of standard biochemical tests, appeared to be Prevotella buccalis, Prevotella denticola, Prevotella melaninogenica, or Prevotella loescheii. However, use of the standard biochemical tests, cellular fatty acid analyses, and the polyacrylamide gel electrophoresis patterns of soluble proteins resulted in conflicting identifications of these strains. The results of tests for cellobiose fermentation, inulin fermentation, and pigment production were responsible for most of the discordant results. Cellular fatty acid analyses in which the Microbial Identification System was used did not differentiate these strains from validly described species, even though separate library entries were created for them. DNA reassociation determinations in which the S1 nuclease procedure was used showed that cellobiose fermentation and pigment production are variable among strains of P. melaninogenica and P. denticola and that fermentation of xylan is not a reliable characteristic for differentiating P. buccalis from Prevotella veroralis. In contrast to previous indications, most strains of P. veroralis do not ferment xylan. These species can be differentiated by DNA-DNA reassociation and by cellular fatty acid analysis, using the Microbial Identification System, but differentiation by currently described phenotypic characteristics is not reliable. Similarly, P. loescheii and the genetically distinct (but closely related) D1C-20 group cannot be distinguished reliably from each other or from P. veroralis, P. denticola, and P. melaninogenica on the basis of currently described phenotypic tests other than cellular fatty acid composition or, for some species, electrophoretic patterns of soluble whole-cell proteins.

Identification of Clostridium botulinum, Clostridium argentinense, and related organisms by cellular fatty acid analysis.

On the basis of 686 analyses of 285 strains of Clostridium botulinum, Clostridium argentinense (formerly C. botulinum type G), and phenotypically related organisms, 14 cellular fatty acid (CFA) groups of toxic organisms and 6 CFA groups of nontoxic organisms were delineated. The CFA groups of toxic strains included two of type A, three of proteolytic strains of type B, two of proteolytic strains of type F, one each of nonproteolytic strains of types B, E, and F, and one each of types C alpha, C beta, and D and C. argentinense. The groups of phenotypically similar nontoxic strains included Clostridium sporogenes, Clostridium putrificum, nontoxic strains with phenotypic characteristics similar to those of nonproteolytic strains of C. botulinum types B, E, and F (BEF-like), two groups of nontoxigenic organisms with phenotypic characteristics similar to those of C. botulinum types C and D and Clostridium novyi (CDN-like), and Clostridium subterminale, which has phenotypic characteristics similar to those of C. argentinense. Within the toxin types, 89 to 100% of the strains were correctly identified by CFA analysis, and 74 to 100% of the analyses were correct. Of 36 strains of C. sporogenes, 30 (83%) were correctly identified; 17% of the strains of C. sporogenes were incorrectly identified as C. botulinum type A or B. All analyses of C. putrificum and C. subterminale were correctly identified. There was no significant level of similarity between strains of C. botulinum and phenotypically similar organisms and 85 other species of clostridia or 407 other taxa of gram-positive and gram-negative bacteria. Additionally, the one strain each of Clostridium baratii and Clostridium butyricum previously reported to produce C. botulinum toxin could be differentiated from C.botulinum types as well as from strains of C. baratii and C. butyricum that did not produce neurotoxin.

Lactobacillus uli sp. nov. and Lactobacillus rimae sp. nov. from the human gingival crevice and emended descriptions of lactobacillus minutus and Streptococcus parvulus.

Lactobacillus uli sp. nov. and Lactobacillus rimae sp. nov. are described. These organisms are short, gram-positive, strictly anaerobic, rod-shaped bacteria that have DNA G+C contents of 53 and 45 mol%, respectively, produce major amounts of lactic acid, and have been isolated from human gingival crevices and periodontal pockets. The major cellular fatty acid derivatives for both species are C18:1 cis-9 fatty acid methyl ester and C18:1 cis-9 dimethylacetyl. The type strain of L. uli is strain VPI D76D-27C (= ATCC 49627), and the type strain of L. rimae is strain D140H-11A (= ATCC 49626). Emended descriptions of Lactobacillus minutus (based on selected strains) and Streptococcus parvulus (based on many additional strains) also are given.

Intrageneric coaggregation among strains of human oral bacteria: potential role in primary colonization of the tooth surface.

Of the 122 human oral bacterial strains tested from 11 genera, only streptococci and a few actinomyces exhibited coaggregation among the strains within their respective genera. Eight of the ten streptococci showed multiple intrageneric coaggregations, all of which were inhibited by galactosides. The widespread intrageneric coaggregation among the streptococci and the less extensive coaggregation among the actinomyces offers an explanation for their accretion on cleaned tooth surfaces and their dominance as primary colonizers.

Actinomyces georgiae sp. nov., Actinomyces gerencseriae sp. nov., designation of two genospecies of Actinomyces naeslundii, and inclusion of A. naeslundii serotypes II and III and Actinomyces viscosus serotype II in A. naeslundii genospecies 2.

DNAs of type strains and representative members of Actinomyces groups from the human periodontal flora and from other habitats were compared by using the S1 nuclease procedure to determine their genetic relatedness. One rather common group from the human periodontal flora, previously called "Actinomyces D08," is phenotypically distinct from, and genetically unrelated to, previously described species. We propose the name of Actinomyces georgiae for this organism; the type strain is strain ATCC 49285. Another common group from the human periodontal flora is Actinomyces israelii serotype II, which was found genetically distinct from the type strain of A. israelii (serotype I) and from other previously described species of Actinomyces. We propose the name Actinomyces gerencseriae for this organism; the type strain is strain ATCC 23860. A. naeslundii serotype I strains were distinct from the other strains studied. A separate genospecies which included strains of A. naeslundii serotypes II and III and A. viscosus serotype II was delineated. Strains of Actinomyces serotype WVA 963 constitute an additional distinct genospecies. Because there are no reliable phenotypic tests, other than serological analyses, to differentiate Actinomyces serotype WVA 963 and the two genospecies of A. naeslundii, no taxonomic changes are proposed for these three genospecies.

Coaggregation of Fusobacterium nucleatum, Selenomonas flueggei, Selenomonas infelix, Selenomonas noxia, and Selenomonas sputigena with strains from 11 genera of oral bacteria.

Twenty-eight strains of Fusobacterium nucleatum and 41 Selenomonas strains, including S. sputigena (24 strains), S. flueggei (10 strains), S. infelix (5 strains), and S. noxia (2 strains), were tested for their ability to coaggregate with each other and with 49 other strains of oral bacteria representing Actinobacillus, Actinomyces, Bacteroides, Capnocytophaga, Gemella, Peptostreptococcus, Porphyromonas, Propionibacterium, Rothia, Streptococcus, and Veillonella species. Selenomonads coaggregated with fusobacteria and with Actinomyces naeslundii PK984 but not with any of the other bacteria, including other selenomonads. In contrast, fusobacteria coaggregated with members of all genera, although not with all strains of each species tested. Each fusobacterium strain appeared to have its own set of partners and coaggregation properties, unlike their partners, whose coaggregation properties in earlier surveys delineated distinct coaggregation groups. Coaggregations of fusobacteria with the 63 gram-negative strains were usually inhibited by EDTA, whereas those with the 27 gram-positive strains were usually not inhibited. Likewise, lactose-inhibitable coaggregations were common among some strains of fusobacteria and some strains from each of the genera containing gram-negative partners but were rarely observed with gram-positive partners. Heating the fusobacteria at 85 degrees C for 30 min completely prevented coaggregation with most partners, suggesting the involvement of a protein on the fusobacteria. Heat treatment of many of the gram-negative partners not only enhanced their coaggregation with the fusobacteria but also changed lactose-sensitive coaggregations to lactose-insensitive coaggregations. Although fusobacteria coaggregated with a broader variety of oral partner strains than any other group of oral bacteria tested to date, each fusobacterium exhibited coaggregation with only a certain set of partner strains, and none of the fusobacteria adhered to other strains of fusobacteria, indicating that recognition of partner cell surfaces is selective. The strains of F. nucleatum are heterogeneous and cannot be clustered into distinct coaggregation groups. Collectively, these results indicate that coaggregation between fusobacteria and many gram-negative partners is significantly different from their coaggregation with gram-positive partners. The contrasting variety of partners for fusobacteria and selenomonads supports the concept of coaggregation partner specificity that has been observed with every genus of oral bacteria so far examined.

Bacteroides species from the oral cavity and oral-associated diseases of cats.

One hundred and sixty-seven strains of Bacteroides were isolated from 71 subcutaneous fight-wound abscesses of cats, 21 cases of feline pyothorax, normal gingival margins from 10 cats and 6 cases of feline gingivitis. Bacteroides species constituted (as a proportion of all anaerobic isolates examined) 44.5% from subcutaneous abscesses, 33.7% from pyothoraxes, 37.5% from normal gingiva and 27.7% from diseased gingiva. Bacteroides tectum comprised 43.7% or 73 of 167 strains, followed by the black- or brown-pigmented asaccharolytic feline species of B. gingivalis, B. salivosus and Group B, comprising 32.3% or 54 of 167 strains. B. heparinolyticus (some 10% or 17 of 167 strains) was the next most common species described. The remainder consisted of two strains of B. fragilis and 21 unspeciated strains. Bacteroides tectum was frequently isolated from subcutaneous abscesses (43.7%) and pyothoraxes (46.6%), and it constituted some 33% of anaerobic isolated from normal gingiva. Bacteroides heparinolyticus was more commonly encountered in purulent lesions (abscesses and pyothoraxes) than in the oral cavity.

Coaggregation properties of human oral Veillonella spp.: relationship to colonization site and oral ecology.

The primary habitats of oral veillonellae are the tongue, dental plaque, and the buccal mucosa. Isolates were obtained from each habitat and tested for coaggregation with a battery of other oral bacterial strains. All 59 tongue isolates tested for coaggregation were Veillonella atypica or Veillonella dispar. All but one of them coaggregated with strains of Streptococcus salivarius, a predominant inhabitant of the tongue surface but not subgingival dental plaque. These tongue isolates were unable to coaggregate with most normal members of the subgingival flora such as Actinomyces viscosus, Actinomyces naeslundii, Actinomyces israelii, and Streptococcus sanguis. In contrast, 24 of 29 Veillonella isolates, of which 20 were Veillonella parvula from subgingival dental plaque samples, coaggregated strongly with the three species of Actinomyces, S. sanguis, and other bacteria usually present in subgingival plaque, but they did not coaggregate with S. salivarius. The majority of isolates from the buccal mucosa (42 of 55) has coaggregation properties like those from the tongue. These results indicate that the three human oral Veillonella species are distributed on oral surfaces that are also occupied by their coaggregation partners and thus provide strong evidence that coaggregation plays a critical role in the bacterial ecology of the oral cavity.

Effect of high-fiber and high-oil diets on the fecal flora of swine.

Six pairs of pigs were fed a basal diet, a high-fiber diet, and a diet high in corn oil in different sequences to minimize the carry-over effect of diet. After 2 months on each diet, a fecal specimen from each pig was cultured on nonselective medium in roll tubes. Fifty colonies were randomly selected from each fecal sample, and isolates were characterized to identify a representative cross section of the fecal flora. The bacterial composition of the fecal flora differed between basal and high-fiber diets (P = 0.002) and between high-fiber and high-oil diets (P = 0.015). However, the floras were not significantly different between the basal and the high-oil diets (P = 0.135), nor were the floras of the 12 individual pigs (each on all three diets) statistically different (P = 0.103). Only 14 of the 160 observed taxa have been detected in the human fecal flora, and only 159 of 1,871 total isolates (8.5%) were members of described species. The most common isolate was a Streptococcus species similar to that reported by Robinson et al. (I. M. Robinson, S. C. Whipp, J. A. Bucklin, and M. J. Allison, Appl. Environ. Microbiol. 48:964-969, 1984), which was found in 34 of 36 samples and which represented 27.5% of all isolates. Lactobacillus, Fusobacterium, Eubacterium, Bacteroides, and Peptostreptococcus species were the next most common bacteria. Escherichia coli represented 1.7% of all fecal isolates, which is somewhat higher than the 0.1 to 0.6% observed in human feces cultured similarly with prereduced anaerobically sterilized media.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteriology of human gingivitis.

The subgingival bacterial floras of naturally occurring gingivitis in adults and children were characterized and compared with the floras of other periodontal conditions previously studied. The composition of the gingivitis floras was found to be distinct from that of floras associated with health or with moderate, severe, or juvenile periodontitis. There were no major differences between the floras of naturally-occurring gingivitis and the floras of the human experimental gingivitis model. Data indicated that the flora of healthy sites within a mouth is influenced by the number of inflamed sites, which argues against independence of sites bacteriologically. Proportions of ten bacterial species increased in both gingivitis and periodontitis, as compared with health, in both adults and children. These species were found in both affected and unaffected sites of people with gingivitis. The numbers of five other cultivable species and the "large treponeme", which was not cultivated, increased in gingivitis and periodontitis of adults only. Significant differences in non-spirochetal floras between children and adults were not found, although they were in the experimental gingivitis model studied previously. Cultivable spirochetes did differ between children and adults. Children had fewer samples positive for spirochetes, and children's positive samples contained greater proportions of T. socranskii subsp. paredis. Some species that predominate in periodontitis, but which are absent from healthy gingivae, were found as a small percentage of the flora in gingivitis. This suggests that increased serum and blood in the gingival crevice encourage species that relate to periodontitis.

Role of porins in intrinsic antibiotic resistance of Pseudomonas cepacia.

The measured outer membrane permeability of Pseudomonas cepacia to the beta-lactam nitrocefin was low: approximately 10 times less than that of Escherichia coli and comparable to that of Pseudomonas aeruginosa. The purified P. cepacia porin demonstrated an average single channel conductance in 1 M KCl of 0.23 nS.