Infect Immun, 1991 Aug, 59(8), 2653 - 7 Pathogen-related spirochetes identified within gingival tissue from patients with acute necrotizing ulcerative gingivitis; Riviere GR et al.; The purpose of this investigation was to determine whether monoclonal antibodies against pathogen-restricted antigens of Treponema pallidum subsp . pallidum could be used as probes for spirochetes in diseased gingival tissue from subjects with acute necrotizing ulcerative gingivitis . A biotin-streptavidin system was used to identify spirochetes bound by monoclonal antibodies in cryostat sections of tissue . Twelve of 16 tissue samples from diseased sites, but none of 8 tissue specimens from healthy sites, reacted with pathogen-restricted antibodies . Organisms were found in intact epithelium and connective tissues adjacent to ulcers . Staining intensity was often high in perivascular locations and around vesicular spaces . Monoclonal antibodies to Bacteroides gingivalis and Treponema denticola were each reactive with diseased gingival tissues, but staining was usually restricted to ulcerated areas . These studies extend recent observations that showed that subjects with acute necrotizing ulcerative gingivitis had both pathogen-related spirochetes in dental plaque and serum immunoglobulin G to pathogen-restricted antigens on T . pallidum subspecies, suggesting that pathogen-related spirochetes may be associated with the pathogenesis of certain periodontal diseases. Glycoconj J, 1991 Aug, 8(4), 376 - 80 Single mid-chain GlcNAc beta 1-6Gal beta 1-4R sequences of linear oligosaccharides are resistant to endo-beta-galactosidase of Bacteroides fragilis; Renkonen O et al.; Endo-beta-galactosidase (EC 3.2.1.103) of Bacteroides fragilis, at 250 mU ml-1, did not cleave the internal galactosidic linkage of the linear radiolabelled trisaccharide GlcNAc beta 1-6Gal beta 1-4GlcNAc, or those of tetrasaccharides Gal beta 1-4GlcNAc beta 1-6Gal beta 1-4GlcNAc and Gal beta 1-4GlcNAc beta 1-6Gal beta 1-4Glc . The isomeric glycans which contained the GlcNAc beta 1-3Gal beta 1-4GlcNAc/Glc sequence were readily cleaved. Oral Microbiol Immunol, 1991 Aug, 6(4), 241 - 5 Adherence to experimental pellicle of rough-type lipopolysaccharides from subgingival plaque bacteria; Okuda K et al.; The adherence of lipopolysaccharides (LPSs) from periodontal disease-associated bacteria to saliva-coated hydroxyapatite (S-HA) and serum-coated HA beads was examined by chromogenic Limulus activity (toxicolor test) . Phenol-water extracted LPS preparations from Bacteroides intermedius, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and rough-type LPS from Escherichia coli adhered to S-HA and serum-coated beads and agglutinated human erythrocytes . The adhered LPSs to S-HA and serum-coated HA beads were not removed by vigorous washing with distilled water . LPSs from Bacteroides (Porphyromonas) gingivalis strains and wild-type E . coli did not adhere to S-HA, serum-coated HA beads or show hemagglutinating activity . SDS-PAGE patterns stained with silver stain showed that LPSs adhered to S-HA, and serum-coated HA beads and erythrocytes possessed a distinct fast-migrating band similar to rough-type LPS . B . gingivalis LPSs possessed slow-migrating and repeating ladder bands similar to wild-type LPS. Pharmazie, 1991 Aug, 46(8), 595 - 6 Influence of anticoagulants on growth and vitamin K production of intestinal bacteria; Johanni M et al.; The influence of anticoagulants on growth and vitamin K production of intestinal bacteria was studied . Bacteroides vulgatus and Escherichia coli were grown in vitro in the presence of increasing amounts of warfarin, phenprocoumon and acenocoumarol . It was found that growth of B . vulgatus was inhibited under anaerobic conditions whereas growth of E . coli under aerobic conditions was not inhibited . A specific inhibition of vitamin K biosynthesis was not observed in either case . It is concluded that therapeutic doses of anticoagulants are unlikely to affect growth or vitamin K production of intestinal bacteria. Appl Environ Microbiol, 1991 Aug, 57(8), 2114 - 20 Conjugal transfer of a shuttle vector from the human colonic anaerobe Bacteroides uniformis to the ruminal anaerobe Prevotella (Bacteroides) ruminicola B(1)4; Shoemaker NB et al.; Prevotella ruminicola (formerly Bacteroides ruminicola) is an anaerobic, gram-negative, polysaccharide-degrading bacterium which is found in the rumina of cattle . Since P . ruminicola is thought to make an important contribution to digestion of plant material in rumina, the ability to alter this strain genetically might help improve the efficiency of rumen fermentation . However, previously there has been no way to introduce foreign DNA into P . ruminicola strains . In this study we transferred a shuttle vector, pRDB5, from the colonic species Bacteroides uniformis to P . ruminicola B(1)4 . The transfer frequency was 10(-6) to 10(-7) per recipient . pRDB5 contains sequences from pBR328, a cryptic colonic Bacteroides plasmid pB8-51, and a colonic Bacteroides tetracycline resistance (Tcr) gene . pRDB5 was mobilized out of B . uniformis by a self-transmissible Bacteroides chromosomal element designated Tcr Emr 12256 . pRDB5 replicated in Escherichia coli as well as in Bacteroides spp . and was also mobilized from E . coli to B . uniformis by using IncP plasmid R751 . However, direct transfer from E . coli to P . ruminicola B(1)4 was not detected . Thus, to introduce cloned DNA into P . ruminicola B(1)4, it was necessary first to mobilize the plasmid from E . coli to B . uniformis and then to mobilize the plasmid from B . uniformis to P . ruminicola B(1)4. J Clin Microbiol, 1991 Aug, 29(8), 1645 - 51 Fluorescence immunoassay for detecting periodontal bacterial pathogens in plaque; Wolff LF et al.; A particle concentration fluorescence immunoassay has been modified into a bacterial concentration fluorescence immunoassay (BCFIA) to rapidly detect periodontopathic bacteria in human plaque samples . The BCFIA utilizes fluorescently tagged monoclonal antibodies (MAbs) directed against the lipopolysaccharide of selected gram-negative plaque bacteria . Microorganisms closely associated with periodontal disease that can be identified in plaque with the BCFIA include Porphyromonas gingivalis, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, and Eikenella corrodens . Briefly, the procedure involved mixing a patient's plaque sample or other bacterial preparation with a species-specific fluorescein isothiocyanate-labeled MAb in a specialized microtiter plate . This mixture was incubated to allow binding of the MAb to its homologous bacteria . The bound and unbound fluorescent tagged MAbs were separated by filtration in the modified microtiter plate, and the total bacterial bound fluorescence was determined with a fluorimeter . The number of a specific bacterial species in a given plaque sample or other bacterial suspension was estimated by reference to a primary standard carried through the BCFIA . The lower detection limit of the BCFIA was 10(3) to 10(4) bacterial cells from single cultures of bacteria or 10(4) bacterial cells in mixed cultures . The coefficient of variation within and between plates for each of the five bacterium-specific MAbs in screening plaque for the periodontal pathogens was less than 10% . These results demonstrate that microbes in plaque can be used as the solid phase in the BCFIA to detect and quantitate MAbs associated with specific bacteria quickly and reliably. J Formos Med Assoc, 1991 Aug, 90(8), 796 - 9 In vitro activities of 36 antimicrobial agents against clinically isolated Bacteroides fragilis; Teng LJ et al.; Thirty-six antimicrobial agents were evaluated for in vitro activities against 100 clinical isolates of Bacteroides fragilis . The minimal inhibitory concentration (MIC) of each agent for each isolate was determined by the agar dilution method . Among 25 beta-lactam antibiotics, the most active agent was imipenem with an MIC90 and a geometric mean of 1 and 0.15 micrograms/ml, respectively; followed by ticarcillin-clavulanic acid, and amoxicillin-clavulanic acid . Ampicillin-sulbactam, piperacillin-tazobactam, moxalactam, and flomoxef were the next most active agents . Piperacillin, ticarcillin, ceftizoxime, cefotaxime, cefuzonam, cefoxitin, and cefmetazole were equally active with the MIC50s ranging from 4 to 16 micrograms/ml, and MIC90s ranging from 32 to greater than or equal to 256 micrograms/ml . The remaining 10 beta-lactam antibiotics, ampicillin, amoxicillin, cefazolin, cefuroxime, cefoperazone, cefmenoxime, ceftazidime, cefpirome, aztreonam, and carumonam were less active . All isolates were resistant to cefotiam at a low breakpoint . Among 6 quinolones, ciprofloxacin was the most active agent with an MIC50 and an MIC90 of 4 and 16 micrograms/ml, respectively . All isolates were resistant to nalidixic acid, pipemidic acid, cinoxacin, enoxacin, and norfloxacin . Among 5 frequently used agents, chloramphenicol, ornidazole, and metronidazole were the most effective agents which inhibited 100% of the isolates at 8, 2, and 2 micrograms/ml, respectively; while clindamycin and minocycline had less activity. J Bacteriol, 1991 Aug, 173(16), 5239 - 43 A site-specific DNA inversion in Bacteroides plasmid pBF4 is influenced by the presence of the conjugal tetracycline resistance element; Matthews BG et al.; pBF4 is a 42-kb R plasmid from Bacteroides fragilis which transfers clindamycin resistance (Clr) independently of the chromosomal tetracycline resistance (Tcr) transfer element . We have found that this plasmid exists in two nonequimolar conformations, A and B . These forms differ by an inversion of approximately 11.5 kb which does not involve the repeated DNA sequences previously mapped on the plasmid . The presence of chromosomal tetracycline resistance conjugal elements influences the relative amounts of the two conformations: induction with tetracycline shifts the dominant form from B to A. Biochem Biophys Res Commun, 1991 Jul 15, 178(1), 336 - 42 Characterization of Porphyromonas (bacteroides) gingivalis hemagglutinin as a protease; Nishikata M et al.; A hemagglutinin (HA) was purified to homogeneity from the membrane fraction of the oral bacterium Porphyromonas gingivalis . The HA possessed protease activity hydrolyzing proteins and arginine-containing synthetic substrates . The protease activity was inhibited by thiol-blocking reagents, and hence the HA can be characterized as a cystein protease . The HA functions as an attachment factor and its substrate-binding site is responsible for the attachment to an erythrocyte. J Med Microbiol, 1991 Jul, 35(1), 18 - 22 Early events after intra-abdominal infection with Bacteroides fragilis and Escherichia coli; Verweij WR et al.; Growth of Bacteroides fragilis and Escherichia coli was monitored during early stages of single (mono-) and mixed intra-abdominal infection in a rat fibrin clot model . When B . fragilis and E . coli were together involved in the infection, B . fragilis numbers increased about 6 h after an initial decline . This increase was not found with B . fragilis mono-infections . The numbers of E . coli increased rapidly in both mono- and mixed infections and stayed high for several days, but only mixed infection resulted in abscesses that persisted for more than 7 days . Macrophages, the main component of the peritoneal cellular defence mechanism, were outnumbered by polymorphonuclear leucocytes during the first 6 h of infection . Further characterisation of the macrophage population by means of monoclonal antibodies showed a shift from resident to exudate macrophages as the result of influx of the latter. J Lab Clin Med, 1991 Jul, 118(1), 48 - 55 Effect of systemic fibrinogen depletion on intraabdominal abscess formation; McRitchie DI et al.; Deposition of fibrin within the peritoneal cavity is an integral host response to local infection . To directly assess the role of fibrin deposition in the pathogenesis of intraabdominal abscess formation, the ability to induce abscesses in fibrinogen-depleted mice was examined . We hypothesized that systemic defibrinogenation with ancrod would limit the availability of fibrinogen for deposition within the peritoneal cavity and would therefore impair intraabdominal abscess formation . A gelatin capsule containing 50% sterile feces plus Bacteroides fragilis 1 x 10(9) CFU was inserted IP into control or defibrinogenated mice . System defibrinogenation resulted in alteration of the character of abscess formation, as manifested by reduced abscess size and degree of purulence . Abscesses were significantly smaller (0.18 +/- 0.02 gm {n = 29} vs . 0.09 +/- 0.02 gm {n = 11}, p less than 0.01) and less purulent (p less than 0.001) in the ancrod-treated mice than in control animals, despite equal numbers of bacteria in the abscesses recovered from both groups . The effect of ancrod was specific for defibrinogenation, because IP repletion with fibrinogen reversed the ancrod effect on abscess size . In addition to its local effects, systemic fibrinogen depletion resulted in a significant elevation in mortality following IP infection (1 of 30 control animals vs . 10 of 23 ancrod-treated animals, p less than 0.01) . However, this was not due to an increase in the magnitude of the B . fragilis bacteremia . These studies demonstrate that fibrin deposition contributes to the pathogenesis of purulent abscess formation and that systemic depletion of fibrinogen may alter host susceptibility to the consequences of infection. J Dent Res, 1991 Jul, 70(7), 1052 - 6 Detection of two anaerobic periodontopathogens in children by means of the BANA and ELISA assays; Watson MR et al.; The mouths of young children become colonized by a variety of bacteria, but there have been only a few studies that have sought the presence of periodontopathic species in this population . Almost all of these studies used culturing techniques rather than the newer detection methodologies for various periodontopathogens . Studies in adults have shown that Treponema denticola and Porphyromonas (Bacteroides) gingivalis can be detected in dental plaque by use of the BANA and ELISA diagnostic tests . In the present study, plaque samples from four subgingival sites in each of 157 children (aged from two to 18 years) were tested for BANA hydrolysis with a BANA reagent card, and for T . denticola and P . gingivalis with an ELISA assay . Anaerobic periodontopathogens hydrolyzing the BANA substrate were found to be present in at least one of four plaque samples in 88 children (56%) . T . denticola and/or P . gingivalis were detected by ELISA in at least one plaque sample in each of 135 children (86%) . This study shows that children are widely colonized by these micro-organisms . A higher proportion of Black children than Caucasian children was colonized by these BANA-positive organisms . Also, children having a parent with a documented history of periodontal disease were more likely to be BANA-positive than were children of parents with unknown periodontal status. J Bacteriol, 1991 Jul, 173(14), 4540 - 3 Use of an Escherichia coli beta-glucuronidase gene as a reporter gene for investigation of Bacteroides promoters; Feldhaus MJ et al.; We have constructed transcriptional fusion vectors for use in Bacteroides spp., a genus of gram-negative obligate anaerobes found in high numbers in the human colon . The reporter group in these vectors is a promoterless beta-glucuronidase gene from Escherichia coli (uidA) . Two of the vectors (pMJF-2 and pMJF-3) replicate in Bacteroides spp . The third, pCQW-1, does not replicate in Bacteroides spp . and can be used to introduce E . coli beta-glucuroindase fusions into the Bacteroides chromosome. Infect Immun, 1991 Jul, 59(7), 2427 - 33 Human immunoglobulin G antibody response to iron-repressible and other membrane proteins of Porphyromonas (Bacteroides) gingivalis; Chen CK et al.; The human immunoglobulin G (IgG) immune response against Porphyromonas (Bacteroides) gingivalis A7A1-28 iron-repressible membrane proteins (IRMPs) and other membrane proteins was examined by immunoblot analysis . Thirty sera from patients with adult periodontitis and 30 sera from periodontally healthy subjects were included . Iron limitation of P . gingivalis was achieved by growing bacteria in brain heart infusion broth supplemented with protoporphyrin IX and 250 microM alpha, alpha'-dypyridyl, a ferrous iron chelator . Iron-sufficient growth was achieved by growing bacteria in the same medium without alpha, alpha'-dypyridyl . Human sera, in particular those from patients with periodontitis who exhibited high levels of IgG against whole cells of P . gingivalis A7A1-28 in serum in an enzyme-linked immunosorbent assay (ELISA), commonly reacted with five membrane proteins with apparent molecular masses of 80, 67.5, 51, 40.5, and 28 kDa and four IRMPs of 46, 43, 37.5, and 22 kDa . More than 80% of the sera from patients with periodontitis and high levels of IgG against strain A7A1-28 in serum by ELISA reacted with the 46-, 43-, and 37.5-kDa IRMPs, and 40% of these subjects expressed immunoreactivity against the 22-kDa IRMP . Sera from patients with periodontitis and low levels of IgG against strain A7A1-28 in serum by ELISA and sera from periodontally healthy subjects exhibited less immunoreactivity against IRMPs and the five membrane proteins of P . gingivalis . The present study indicates that P . gingivalis IRMPs are immunogenic and that these proteins are expressed in vivo. Indian J Med Res, 1991 Jul, 93, 236 - 9 Isolation of anaerobes from clinical chancroid associated with fluctuant bubo in men; Kumar B et al.; Microbial flora especially anaerobes were studied in 67 patients with genital ulcers due to chancroid (diagnosed clinically) and 53 controls with genital ulcers due to other causes . The aerobic flora was similar in patients of chancroid with or without associated bubo and in controls . Anaerobes were however, isolated with higher frequency from chancroid ulcers associated with fluctuant bubo compared to those without bubo (P less than 0.01) and with non-fluctuant bubo (P less than 0.05) . Anaerobic bacteria like Bacteroides melaninogenicus, B . fragilis and anaerobic cocci may play a role in the perpetuation of genital ulcers and development of bubo in chancroidPIP: The microbial isolates in 67 men with genital ulcers due to chancroid and 53 controls with genital ulcers due to other causes were investigated . The study subjects comprised 14% of men presenting to a sexually transmitted disease facility in India in 1986 . Bubo was present in 37 of the chancroid patients and was fluctuant in 20 . At least 1 organism was isolated in both subjects and controls . Monomicrobial growth was observed in 20 chancroid patients and 20 controls; the remainder were polymicrobial . Anaerobic cocci were isolated in 44 (66%) of men with chancroid and 25 (47%) of those with ulcers of miscellaneous etiology, while aerobes were present in 52 (77%) men with chancroid and 39 (73%) controls . Finally, anaerobes were isolated in 17 (57%) of ulcers without bubo, 11 (65%) of ulcers with nonfluctuant bubo, and 18 (90%) of chancroid ulcers associated with fluctuant bubo . There was a significant difference in the anaerobe isolation rate in men with fluctuant bubo and those without bubo (pp0.01) and between patients with fluctuant non nonfluctuant bubo (p0.05) . The finding that anaerobes were isolated more frequently, but not at a statistically significant level, from chancroid ulcers than ulcers of other etiology fails to support the hypothesis that anaerobes are a major cause of chancroid . On the other hand, the data do support the view that anaerobes such as anaerobic cocci and Bacteroides melaninogenicus are significant in the perpetuation of chancroid ulcers and the development of fluctuant bubo . Indian J Med Res, 1991 Jul, 93, 232 - 5 Virulence factors in Bacteroides fragilis group; Jotwani R et al.; Attempts were made to study the virulence factors in some strains of B . fragilis group in the rat model . Subcutaneous wound abscesses could be produced by 10(9) CFU/ml of live cells of all the five species of B . fragilis group tested . For determination of virulence factor cellular components (capsular polysaccharide and lipopolysaccharide) of B . fragilis were separated using gel filtration technique and injected in rats . Abscesses could be produced only by capsular polysaccharide fraction suggesting it to be the virulence factor . Studies with transmission electron microscope showed presence of capsular polysaccharide in B . fragilis and B . thetaiotaomicron, it was doubtful in B . distasonis and absent in B . ovatus and B . vulgatus . This suggested that virulence factors other than capsular polysaccharide may be responsible for pyogenic lesions in the noncapsulated species of B . fragilis group . The abscess could not be produced by 10(9) CFU/ml of heat killed cells of non-capsulated B . ovatus and B . vulgatus indicating that in live bacteria, a heat labile factor was responsible for the development of abscess. Rev Infect Dis, 1991 Jul-Aug, 13(4), 633 - 6 Anaerobic bacteremia: decreasing rate over a 15-year period; Dorsher CW et al.; At the Mayo Clinic, the number of cases of anaerobic bacteremia decreased 45% between 1974 and 1988 . In addition, the percentage of blood cultures positive for anaerobes decreased significantly even though the total number of blood cultures performed increased . The number of anaerobic bacteremias per 100,000 patient-days also declined over the 15-year period . Organisms of the Bacteroides fragilis group ranked third in frequency with respect to other organisms that caused aerobic and anaerobic bacteremia in 1974 but ranked only seventh in 1988 and caused slightly less than one-half of the anaerobic bacteremias . The mechanisms responsible for these changes are unclear but might relate to earlier recognition and treatment of localized anaerobic infection, widespread preoperative use of agents prior to bowel surgery, and use of broad-spectrum antimicrobial regimens that include agents with activity against anaerobes. J Clin Periodontol, 1991 Jul, 18(6), 406 - 10 Microbiology in the management of destructive periodontal disease; van Winkelhoff AJ et al.; This paper summarizes the rationale for the application of microbiology in the management of destructive periodontal diseases . The subgingival microbiota in patients with severe periodontitis is complex and contains high numbers of obligate anaerobic bacteria as well as facultative micro-organisms . It has become clear that major differences exist in the composition of the subgingival microflora . These differences are not only quantitative but also qualitative . Difference in plaque composition is the basis for the application of clinical microbiology in the management of periodontal disease . Several bacterial species have emerged as useful indicators for progressive periodontitis . In this respect, the importance of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Bacteroides intermedius has been shown in a number of studies . It has become clear that A . actinomycetemcomitans is not specifically associated with the local form of juvenile periodontitis, but this micro-organism is probably also of importance in severe periodontitis in adult patients . Selection of individuals with an A . actinomycetemcomitans associated periodontitis is essential since successful treatment in these patients needs an adjunctive antibiotic therapy . Microbiological testing can be useful in patients showing a poor response to periodontal treatment (refractory periodontitis) . Factors which may be responsible include poor oral hygiene, poor subgingival debridement, the patient's susceptibility and a subgingival microflora resistant to therapy . In this patient category, microbiological testing is capable of diverting continuing periodontal treatment . Furthermore, microbiology can be useful in evaluating periodontal treatment . Successful elimination of specific periodontopathic microorganisms can be used to determine recall intervals. J Bacteriol, 1991 Jul, 173(14), 4263 - 70 Identification of Porphyromonas gingivalis components that mediate its interactions with fibronectin; Lantz MS et al.; Porphyromonas (Bacteroides) gingivalis W12 binds and degrades human plasma fibronectin . In the presence of the protease inhibitor N-alpha-p-tosyl-L-lysyl chloromethyl ketone, P . gingivalis cells accumulated substantial amounts of 125I-fibronectin as a function of incubation time . Fibronectin binding was specific, reversible, and saturable . The Kd for the reaction was estimated to be on the order of 100 nM, and there was an average of 3.5 x 10(3) fibronectin binding sites per cell . Unlabeled fibronectin inhibited the binding of 125I-fibronectin to bacteria; however, fibrinogen was an even more efficient inhibitor of 125I-fibronectin binding . Unrelated proteins were without effect on fibronectin binding . A fibronectin-binding component (Mr, 150,000) was identified in sodium dodecyl sulfate-solubilized P . gingivalis . Fibronectin was degraded into discrete peptides by P . gingivalis W12 . The degradation of fibronectin was inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone . Two P . gingivalis components (Mrs, 120,000 and 150,000) degraded fibronectin in substrate-containing gels following sodium dodecyl sulfate-polyacrylamide gel electrophoresis . In a previous study (M . S . Lantz, R . D . Allen, T . A . Vail, L . M . Switalski, and M . Hook, J . Bacteriol . 173:495-504, 1991), we found that the same strain of P . gingivalis bound and subsequently degraded human fibrinogen via apparently distinct cell surface components of molecular sizes similar to those of components now implicated in the binding and degradation of fibronectin . These results raise the possibility that the two ligands are recognized and modified by the same components on P . gingivalis W12 . In support of this hypothesis, unlabeled fibrinogen effectively inhibited the binding of 125I-fibronectin to bacteria and blocked 125I-fibronectin binding to a P . gingivalis ligand-binding component (Mr, 150,000 immobilized on a nitrocellulose membrane. J Antimicrob Chemother, 1991 Jul, 28(1), 55 - 60 Comparative susceptibility of cefminox and cefoxitin to beta-lactamases of Bacteroides spp; Soriano F et al.; The susceptibility of the new cephamycin antibiotic, cefminox, to hydrolysis by various types of beta-lactamase produced by organisms of the Bacteroides fragilis group was compared with that of cefoxitin . Several enzymes were able to achieve complete hydrolysis of both drugs during overnight incubation, but no marked difference between the rates of inactivation of cefminox and cefoxitin was observed . Susceptibility of the cephamycins to crude extracts of beta-lactamases from the test strains of Bacteroides spp . did not correlate with the results of conventional minimum inhibitory concentration titrations . Possible reasons for these discrepancies are discussed. J Antimicrob Chemother, 1991 Jul, 28(1), 47 - 53 Lactate dehydrogenase activity as a cause of metronidazole resistance in Bacteroides fragilis NCTC 11295; Narikawa S et al.; Enzymes acting on pyruvate as a parameter of the ATP regeneration system were studied as a cause of metronidazole resistance in Bacteroides fragilis NCTC 11295 . The resistant strain had higher lactate dehydrogenase activity and produced more lactate than susceptible strains, suggesting that the enzyme is more active in lactic acid fermentation . Furthermore, the reaction catalysed by lactate dehydrogenase occurred up to 48 mg/L metronidazole, whereas the reaction catalysed by pyruvate: ferredoxin oxidoreductase reaction stopped at 2 mg/L . The mechanism of metronidazole resistance in B . fragilis NCTC 11295 may be due to the high activity of lactate dehydrogenase which compensates for the decreased activity of pyruvate: ferredoxin oxidoreductase in the presence of metronidazole. J Dent Hyg, 1991 Jul-Aug, 65(6), 289 - 95 The effects of subgingival irrigation with chlorhexidine and stannous fluoride . A preliminary investigation; Krust KS et al.; This pilot study compared the effectiveness of subgingival irrigation with 0.12% chlorhexidine, 1.64% stannous fluoride, and sterile saline, in addition to scaling and root planing, on levels of Bacteroides porphyromonas and the clinical parameters bleeding tendency, probing depth, and attachment level . A convenience sample of eight patients, exhibiting 32 sites with moderate periodontal disease, was randomly assigned to receive all treatments according to a four-quadrant treatment design . Subgingival irrigation was performed at 0, 1, 2, and 3 weeks following scaling and root planing . Clinical and microbial assessments were measured at baseline, 4, 8, and 12 weeks . Data were analyzed using a two-factor repeated measure analysis of variance, and the Newman-Keuls sequential range test or Friedman test and Kruskal-Wallis test revealed statistically significant (p less than .01) improvements in probing depths, attachment levels, and Bacteroides porphyromonas for all groups at 12 weeks when compared to baseline values . No statistically significant differences occurred between any of the treatment groups at any time period . Based on the findings of this investigation, it has been concluded that four weekly irrigations with 0.12% chlorhexidine, 1.64% stannous fluoride, or saline irrigation did not enhance the beneficial effects of scaling and root planing alone. J Chromatogr, 1991 Jun 21, 546(1-2), 273 - 87 Ion chromatographic methods for the detection of starch hydrolysis products in ruminal digesta; Barsuhn K et al.; Dionex high-performance ion chromatographic methods were evaluated for separation and quantitation of plant sugars and starch digestion products in the ruminal digesta of cattle . Mono- and disaccharides were eluted from a Dionex CarboPac PA1 column with sodium hydroxide used isocratically or as a pH gradient . Maltooligosaccharides which had a degree of polymerization (DP) less than 30 glucose residues were eluted in 60 min by a sodium hydroxide eluent containing a sodium acetate gradient . Carbohydrates were detected amperometrically . Responses were linear (r2 greater than 0.99) for glucose, disaccharides and maltooligosaccharides (DP less than 8) . Precipitation and solid-phase extraction methods were evaluated for clean-up of samples of feedstuffs, ruminal contents, and bacterial culture fluids . Perchloric acid precipitation hydrolyzed sucrose but did not affect recoveries of cellobiose, isomaltose or maltose . Ethanol in concentrations of 79 and 86% precipitated maltooligosaccharides having chain lengths larger than 14 and 9 glucose residues, respectively . Maltooligosaccharide recoveries from solid-phase extraction columns varied with maltooligosaccharide size and column packing . Recoveries were greater than 94% for short chains (DP less than 6) eluted from phenyl-substituted columns and variable for all oligosaccharides eluted from C18 columns . Applications of these methods are presented and include: (1) detection of sugars in ruminant feed, (2) monitoring changes in ruminal sugars after feeding and (3) monitoring changes in extracellular sugars and oligosaccharides in the culture fluids of the ruminal bacterium, Bacteroides ruminicola. Postgrad Med, 1991 Jun, 89(8), 221 - 4, 227-30, 233-4 Anaerobic infections . The basics for primary care physicians; Feleke G et al.; Anaerobic bacteria constitute a major portion of the normal human microflora, and some of them can cause disease in contiguous body parts, especially if there is a mucosal break . Most anaerobic infections are polymicrobial . Because anaerobes are difficult to culture, diagnosis is often made on the basis of clinical clues . Thus, knowledge of the common sites, predisposing conditions, and other representative features of anaerobic infections is critical . For anaerobic infections above the diaphragm, where Bacteroides fragilis is not a common isolate, high-dose penicillin G therapy is usually sufficient . Addition of clindamycin (Cleocin) or metronidazole (Flagyl, Metryl, Protostat) may be necessary for serious infections . Cefoxitin sodium (Mefoxin) or clindamycin is adequate for most anaerobic infections occurring outside the central nervous system . Metronidazole, chloramphenicol, imipenem, or beta-lactam antibiotics combined with beta-lactamase inhibitors may be preferable for serious infections . Appropriate coverage for aerobic bacteria must be included in the treatment regimen . Drainage of abscesses, decompression of infected spaces, debridement of necrotic tissue, and removal of foreign bodies are critical in management of many anaerobic infections. Infect Immun, 1991 Jun, 59(6), 2075 - 82 Immunochemical characterization of two surface polysaccharides of Bacteroides fragilis; Pantosti A et al.; Immunochemical analysis of the capsular polysaccharide from Bacteroides fragilis NCTC 9343 revealed a novel structure composed of two distinct polysaccharides . Immunoelectrophoresis of an extract of purified surface polysaccharide from fermenter-grown organisms showed a complex precipitin profile with varying anodal mobility . DEAE-Sephacel anion-exchange chromatography of the polysaccharide extract failed to separate the majority of this aggregate . Disaggregation of this complex was accomplished by very mild acid treatment; purification was achieved by DEAE-Sephacel anion-exchange chromatography . Polysaccharide A had a neutral charge at pH 7.3, a net negative charge at pH 8.6, and an average Mr = 110,000; chemical analysis showed it to contain galactose, galactosamine, and an unidentified amino sugar . Polysaccharide B eluted from the anion-exchange column with increased salt concentration; it had a net negative charge and an average Mr = 200,000, and contained fucose, galactose, quinovosamine, galacturonic acid, and glucosamine . Neither of these polysaccharides contained detectable 3-deoxy-D-manno-octolusonic acid, and both were recognized as distinct antigens on the basis of their reactivity with monoclonal antibodies CE3 and F10, which reacted with the complex before acid treatment . These data indicate that the capsule of B . fragilis NCTC 9343 comprises two discrete, surface-exposed polysaccharides with differing physiochemical properties that are distinct from the lipopolysaccharide of this organism . The finding of two surface polysaccharides has not been described for other bacteria pathogenic to humans. Infect Immun, 1991 Jun, 59(6), 1927 - 31 Immune modulation of Prevotella intermedia colonization in squirrel monkeys; Clark WB et al.; Colonization of the gingival crevice by black-pigmented Porphyromonas or Prevotella spp . (BP/P), including Porphyromonas gingivalis (formerly Bacteroides gingivalis) and Prevotella intermedia (formerly Bacteroides intermedius), is thought to be an important ecological event which may result in the destruction of connective tissues supporting the teeth . Theoretically, periodontal diseases could be prevented if these or other periodontal pathogenic microorganisms did not colonize the subgingival area . The humoral immune response is one mechanism which may modulate bacterial colonization in the gingival crevice . In the present study, we tested the effect of systemic humoral immunity on subgingival colonization by indigenous P . intermedia in squirrel monkeys (Saimiri sciureus) . Animals rendered essentially free of detectable BP/P by a single scaling, 10 days of tetracycline therapy, and toothbrushing three times per week were immunized with P . intermedia 1447 or were sham immunized with phosphate-buffered saline . Subsequently, all oral hygiene procedures were discontinued and five teeth in one quadrant were ligated with bacterium-soaked suture material to facilitate BP/P colonization . Immunization resulted in a significant increase in the level of immunoglobulin G anti-P . intermedia antibody in serum . Two weeks after ligation was initiated, P . intermedia could be detected in five of six sham-immunized and three of six immunized animals . Immunization was associated with a reduction in the emergence of indigenous P . intermedia in the gingival crevice. J Biol Buccale, 1991 Jun, 19(2), 155 - 60 Targetting the production of monoclonal antibodies to the hemagglutinating adhesin of Bacteroides (Porphyromonas) gingivalis by injection of an immunoprecipitate from crossed immunoelectrophoresis; Deslauriers M et al.; This study has demonstrated that the production of monoclonal antibodies (MAbs) can be targetted to a predetermined antigen by immunization with the relevant immunoprecipitate (IP) excised from an agarose gel . The target antigen was the hemagglutinating adhesin HA-Ag2 of Bacteroides (Porphyromonas) gingivalis precipitated from a crude antigen extract with a rabbit antiserum in crossed immunoelectrophoresis . The immunization protocol used included: subcutaneous injection of 1 IP in Freund's complete adjuvant to Balb/c mice on day 0 and of 0.5 IP on day 8, followed by an intravenous booster injection of outer membranes on day 15, 4 days before the fusion . Of the 9 MAbs obtained, 8 were specific for HA-Ag2 since they reacted with its characteristic electrophoretic bands at 43 and 49 kDa . The ninth MAb was specific for the B . gingivalis lipopolysaccharide . The method allows for easy obtention of MAbs of predetermined specificity without purification of the antigen. J Antimicrob Chemother, 1991 Jun, 27(6), 721 - 31 Susceptibility of Bacteroides ureolyticus to antimicrobial agents and identification of a tetracycline resistance determinant related to tetM; de Barbeyrac B et al.; The in-vitro activity of ten antimicrobial agents was evaluated for 28 clinical isolates of Bacteroides ureolyticus, an obligate anaerobe associated with non-gonococcal urethritis . The isolates were characterized by plasmid DNA profile and PAGE protein pattern . All isolates were inhibited at concentrations equal to or lower than the recommended breakpoint concentration for ampicillin (16 mg/l), metronidazole (16 mg/l) and erythromycin (4 mg/l) . Twenty-seven isolates were inhibited by less than or equal to 2 mg/l of ciprofloxacin, pefloxacin and ofloxacin . Four isolates were tetracycline-resistant requiring 2-64 mg/l of tetracycline, minocycline or doxycycline for inhibition . In two tetracycline-resistant isolates tetM was demonstrated by dot-blot and Southern hybridizations . These two isolates did not contain a plasmid and had a PAGE protein pattern type III . These data confirm the spread of the tetM determinant in various bacteria of the genital tract. Antimicrob Agents Chemother, 1991 Jun, 35(6), 1219 - 24 Effect of beta-lactamase inhibitors on the activities of various beta-lactam agents against anaerobic bacteria; Wexler HM et al.; The in vitro activities of several new beta-lactam-beta-lactamase inhibitor combinations (piperacillin plus tazobactam, ceftizoxime and cefonicid with sulbactam and clavulanic acid, and ampicillin plus 8 micrograms of sulbactam per ml) were tested with anaerobic bacteria and compared with known beta-lactam-beta-lactamase inhibitor combinations and other potent antianaerobe agents . All the combinations tested (except for the cefonicid-inhibitor combinations) were active against almost all strains of the Bacteroides fragilis group . This report indicates that beta-lactamase inhibitors may improve the activity of beta-lactam agents with marginal activity against the B . fragilis group. Antimicrob Agents Chemother, 1991 Jun, 35(6), 1214 - 8 Susceptibilities of 394 Bacteroides fragilis, non-B . fragilis group Bacteroides species, and Fusobacterium species to newer antimicrobial agents; Appelbaum PC et al.; The susceptibilities of 374 selected beta-lactamase-producing gram-negative anaerobes (including 22 cefoxitin-resistant strains and 36 strains refractory to the enhancing effect of beta-lactamase inhibitors) and 20 beta-lactamase-negative strains were tested by agar dilution against selected new agents . The organisms included 217 Bacteroides fragilis group strains, 137 non-B . fragilis group Bacteroides spp., and 40 fusobacteria . All strains were susceptible to piperacillin-tazobactam, imipenem, and meropenem . For the B . fragilis group, 96% were susceptible to ampicillin-sulbactam, 95% were susceptible to amoxicillin-clavulanate and cefoperazone-sulbactam, 94% were susceptible to tosufloxacin, 91% were susceptible to cefoxitin, 88% were susceptible to trospectomycin, and 73% were susceptible to cefotetan . For the beta-lactamase-positive non-B . fragilis group Bacteroides spp., greater than or equal to 94% were susceptible to cefoxitin, amoxicillin-clavulanate, ampicillin-sulbactam, cefoperazone-sulbactam, and trospectomycin, 90% were susceptible to cefotetan, and 85% were susceptible to tosufloxacin (the most resistant strains were B . bivius and B . disiens) . For the beta-lactamase-positive fusobacteria, greater than or equal to 97% were susceptible to amoxicillin-clavulanate, ampicillin-sulbactam, cefoperazone-sulbactam, trospectomycin, and cefoxitin, 90% were susceptible to cefotetan, and 89% were susceptible to tosufloxacin . All agents showed excellent activity against beta-lactamase-negative strains (for trospectomycin, 95% were susceptible; for all other drugs, 100% were susceptible) . Overall, both carbapenems and piperacillin-tazobactam were most active . Amoxicillin-clavulanate, ampicillin-sulbactam, and cefoperazone-sulbactam lacked activity against some cefoxitin-resistant B . fragilis group strains but had excellent activity against other organisms . Tosufloxacin, a new quinolone, had very good activity against B . fragilis group strains (94% susceptible), good activity against other beta-lactamase-positive strains (less than or equal 85% susceptible), and excellent activity against beta-lactamase-negative strains (100% susceptible; MIC for 90% of strains, 0.5 microgram/ml) . Trospectomycin was active against >90% of all strains except for B . fragilis group strains (88% susceptible; MIC for 90% of strains, 32 microgram/ml) . Clinical studies are required to delineate the role of newer agents in the therapy of anaerobic infections. J Vet Pharmacol Ther, 1991 Jun, 14(2), 185 - 92 Comparative in vitro susceptibility of Bacteroides and Fusobacterium isolated from footrot in sheep to 28 antimicrobial agents; Piriz Duran S et al.; The agar dilution method was used to determine the bacteriostatic activity of 28 antimicrobial agents against 141 strains to the genus Bacteroides and 29 strains from the genus Fusobacterium . All organisms were isolated from clinical cases of ovine footrot . The strains were isolated from 125 Merino sheep, over a period of 2 years, from January 1987 to December 1988 . The three ureidopenicillins studied (azlocillin, mezlocillin and piperacillin) proved to be the most effective antimicrobial agents . Chloramphenicol, metronidazole and tinidazole effectively inhibited the growth of Bacteroides spp., while phosphomycin was active against Fusobacterium spp. J Gen Microbiol, 1991 Jun, 137 ( Pt 6), 1445 - 52 Multivariate analyses of fatty acid data from whole-cell methanolysates of Prevotella, Bacteroides and Porphyromonas spp; Brondz I et al.; The genus Bacteroides contains a number of biochemically and physiologically heterogeneous groups of organisms and needs taxonomic revision . In this study cellular fatty acids from a number of Bacteroides spp . were identified and quantified using gas chromatography and gas chromatography-mass spectrometry . The chemical data were then subjected to principal components analysis . In B . fragilis, which is the type species of the genus Bacteroides, C3-OH-iso17 was the predominant fatty acid (38.0%) and Cante15 was present in higher amounts (32.7%) than Ciso15 (14.6%) . B . fragilis thus differed from all the other species examined: Prevotella (Bacteroides) buccae, P . (B.) oralis, P . (B.) oris, P . (B.) disiens, P . (B.) veroralis, P . (B.) heparinolytica and Porphyromonas (Bacteroides) endodontalis . Principal components analysis also enabled the closely related P . buccae, P . oralis and P . oris to be differentiated. J Gen Microbiol, 1991 Jun, 137 ( Pt 6), 1431 - 5 A study of the candidate virulence factors of Bacteroides fragilis; Namavar F et al.; Bacteroides fragilis strains were classified as virulent or avirulent on the basis of their clearance from the subcutaneous tissues of mice . To determine the factors which may contribute to the virulence of B . fragilis strains, we studied encapsulation, hydrophobicity, growth rate, serum sensitivity, agglutination with erythrocytes of different origin, and neuraminidase production . The strains of the virulent group displayed a higher growth rate in broth and a lower sensitivity to the bactericidal activity of serum than the strains of the avirulent group . They also agglutinated different types of erythrocytes more strongly than did the avirulent strains . No significant differences were found between the two groups of strains as regards encapsulation, hydrophobicity and neuraminidase activity. Br J Oral Maxillofac Surg, 1991 Jun, 29(3), 180 - 2 British oral and maxillofacial surgeons' views on the aetiology and management of acute pericoronitis; Gill Y et al.; Acute pericoronitis is a common oral infection characterised by a predominance of anaerobic micro-organisms such as peptococci, peptostreptococci, bacteroides and fusobacteria, and also spirochaetes . Penicillins such as amoxycillin, and metronidazole are effective antimicrobials in the treatment of acute pericoronitis . This study presents the views of a group of British Oral and Maxillofacial Surgeons as to the causative microbial agents and the antimicrobial management of acute pericoronitis. J Periodontol, 1991 Jun, 62(6), 377 - 86 Incidence of periodontitis recurrence in treated patients with and without cultivable Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis: a prospective study; Listgarten MA et al.; A total of 98 adults previously treated for moderate to advanced periodontitis and on a trimonthly recall schedule were screened for the presence of critical levels of Actinobacillus actinomycetemcomitans, Prevotella (Bacteroides) intermedia, and Porphyromonas (Bacteroides) gingivalis . Patients with at least 2 positive sites were placed in a positive group and patients without or with low levels of these bacteria in a negative group . During the 30-month study the incidence of disease recurrence was greater in the positive group, but did not reach statistical significance . Positive patients with deeper pockets tended to be at greater risk of developing recurrent disease than those with shallower pockets . In the positive group only, both A . actinomycetemcomitans recovery and antibody levels to A . actinomycetemcomitans strain NCTC 9710 (serotype c) were inversely correlated with disease recurrence . The presence of A . actinomycetemcomitans and P . intermedia above critical levels did not reliably predict future episodes of disease recurrence in this population . The sparse recovery of P . gingivalis did not permit us to assess its diagnostic value . With the exception of P . gingivalis, for which insufficient data were available, the results indicate that the presence or absence of the above bacterial species cannot of itself serve as a reliable predictor of future episodes of recurrent disease in a population of treated patients on a regular trimonthly recall schedule. Infect Immun, 1991 Jun, 59(6), 1972 - 7 Bacteroides (Porphyromonas) gingivalis fimbriae activate mouse peritoneal macrophages and induce gene expression and production of interleukin-1; Hanazawa S et al.; The purpose of this study was to examine whether Bacteroides (Porphyromonas) gingivalis fimbriae, an important structure involved in attachment of the bacteria to periodontal tissues, activate macrophages and subsequently induce gene expression and production of interleukin-1 (IL-1) in the cells . The fimbriae increased glucose consumption and lysozyme activity in BALB/c macrophages, both criteria of macrophage activation of peritoneal macrophages, in a dose-dependent fashion . A marked increase in the mRNA level of the c-myc gene, an oncogene, in the cells was observed after a 1-h treatment with the fimbriae, and the level decreased rapidly after 3 h . The fimbriae (4 micrograms of protein per ml) markedly induced IL-1 alpha and IL-1 beta gene expression in the cells and IL-1 production . The expression of IL-1 alpha and IL-1 beta genes measured in terms of specific mRNA increased 1 h after the start of treatment and peaked at 6 h . Such increased expression of IL-1 beta was also observed in C3H/HeJ mice, a lipopolysaccharide low-responder strain . The fimbriae stimulated transcriptional activity of IL-1 beta in the cells, but not that of IL-1 alpha . We also observed that fimbriae-induced IL-1 gene expression was not regulated by endogenous prostaglandin triggered by the fimbriae . Therefore, these observations suggest that B . gingivalis fimbriae may be involved in the pathogenesis of adult periodontal disease via triggering of IL-1 production by monocytes/macrophages in periodontal diseases. Afr J Med Med Sci, 1991 Jun, 20(2), 115 - 21 Rapid presumptive identification of human black pigmented Bacteroides species; Eke PI et al.; A simple and reliable technique is described for the rapid presumptive identification of black pigmented Bacteroides species of human origin . This method involved a microtitration technique that detected the hydrolysis of specific chromogenic enzyme substrates and haemagglutination of sheep erythrocytes . Pure cultures of black pigmented Bacteroides strains, representing the eight human species, were successfully differentiated and identified within 4 h by the identification scheme developed with this method . This is a highly reproducible method and the scheme should be useful in laboratories lacking the sophisticated equipment often needed for the identification of black pigmented Bacteroides. Appl Environ Microbiol, 1991 Jun, 57(6), 1615 - 23 A Bacteroides ovatus chromosomal locus which contains an alpha-galactosidase gene may be important for colonization of the gastrointestinal tract; Valentine PJ et al.; An alpha-galactosidase gene has been cloned from the human colonic Bacteroides species Bacteroides ovatus 0038 . This alpha-galactosidase appears to be distinct from two previously characterized alpha-galactosidases, I and II, from the same strain and has been designated alpha-galactosidase III . Partially purified alpha-galactosidase III from Escherichia coli EM24 containing pFG61 delta SE had a pI of 7.6, as compared with the reported pI values for the known alpha-galactosidases of 5.6 for I and 6.9 for II . Its molecular weight as estimated on sodium dodecyl sulfate-polyacrylamide gels was 78,000, whereas the molecular weights of alpha-galactosidases I and II were 85,000 and 80,500, respectively . The only substrate hydrolyzed by alpha-galactosidase III was melibiose, whereas the other two alpha-galactosidases were able to degrade melibiose, raffinose, and stachyose and partially degraded guar gum . alpha-Galactosidase III had a pH optimum of 6.7 to 7.2 . Finally, a single crossover insertion which disrupted the gene in the B . ovatus chromosome had no effect on expression of alpha-galactosidases I and II . Although this insertion had no effect on the ability of B . ovatus to grow in laboratory medium on any of the galactoside-containing carbohydrates tested, the insertion mutant was outcompeted by wild type when a combination of mutant and wild type was used to colonize germfree mice . Insertions on either side of the gene had the same effect . Thus, the locus which contains alpha-galactosidase III may be important for colonization in vivo.(ABSTRACT TRUNCATED AT 250 WORDS) J Periodontol, 1991 Jun, 62(6), 394 - 401 Defective neutrophil function in an insulin-dependent diabetes mellitus patients . A case report; Cutler CW et al.; The objective of this study was to evaluate the polymorphonuclear leukocyte (PMN) function in a poorly controlled adult insulin-dependent diabetic patient (IDDM) with severe recurrent periodontitis, while describing the microbiological and clinical findings . Chemotaxis, superoxide production, and phagocytosis and killing of Porphyromonas (Bacteroides) gingivalis by the IDDM PMN were evaluated 1 week before treatment relative to a healthy, matched control . These analyses revealed a significant (P less than .05) depression in the number of IDDM PMNs migrating along an FMLP gradient (Boyden chamber assay) . In addition, a significant (P less than .05) enhancement of IDDM PMN superoxide production in response to opsonized zymosan (cytochrome C reduction) was observed . Phagocytosis and killing (fluorochrome phagocytosis assay) by IDDM PMN of two P . gingivalis strains was also impaired significantly (P less than .05) . The subgingival microflora contained significant levels of P . gingivalis, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and Peptostreptococcus micros . Periodontal treatment consisted of extraction of hopeless teeth, scaling and root planing and 3 weeks of Augmentin therapy . The antibiotic therapy resulted in unrecoverable numbers of the putative pathogens and a reduction in both gingival inflammation and disease progression . The IDDM healing response to previous surgical treatment and extractions was poor, presumably due to a marked thrombocytopenia (91 x 10(3) platelets/mm3). J Med Microbiol, 1991 May, 34(5), 253 - 7 The resolution of bacteroides lipopolysaccharides by polyacrylamide gel electrophoresis; Maskell JP; The lipopolysaccharides (LPS) of the 10 species of the genus Bacteroides (sensu stricto) were extracted by the proteinase K method and their resolution compared by several methods of polyacrylamide gel electrophoresis (PAGE) . These included sodium dodecyl sulphate (SDS)-PAGE with and without urea, polyacrylamide gradient gels and Tricine {N-Tris (hydroxymethyl) methyl glycine}-SDS-PAGE . The original discontinuous system showed good resolution of LPS from B . thetaiotaomicron, B . caccae and B . ovatus and this was enhanced by urea; B . vulgatus showed a typical ladder pattern associated with repeating polysaccharide units of the O side chains . The LPS profiles of the other species, including B . fragilis, were poorly resolved; the majority of components migrated with the leading edge of the wave front . The resolution of the LPS of these species was marginally improved with gradient gels but the majority of components were separated only within the regions of high polyacrylamide concentration . The Tricine-SDS system was consistently superior to the other methods, with excellent resolution of the LPS profiles of all Bacteroides species. Mol Microbiol, 1991 May, 5(5), 1211 - 9 Escherichia coli chromosomal mutations that permit direct cloning of the Bacteroides fragilis metallo-beta-lactamase gene, ccrA; Rasmussen BA et al.; The class B, metallo-beta-lactamase genes ccrA (carbapenem- and cephamycin resistance) from three Bacteroides fragilis isolates--QMCN3, QMCN4, and TAL3636--were cloned and expressed in Escherichia coli . Cloning of the genes, by selecting for ampicillin resistance, was facilitated by two classes of Escherichia coli chromosomal mutations which resulted in at least a 5-10-fold increase in metallo-beta-lactamase enzymatic activity . The observed increase in enzymatic activity is due to either increased translation of the ccrA gene or an effect on localization or stability of the protein . Comparison of the DNA sequences of the three ccrA genes revealed that their protein-coding sequences shared greater than 97% DNA sequence identity . However, the 5' upstream sequence for the TAL3636 ccrA gene was unrelated to that of the other two genes. Indian J Med Res, 1991 May, 93, 171 - 3 Detection of Bacteroides infection by counter immunoelectrophoresis test; Lalitha MK et al.; The counterimmunoelectrophoresis (CIE) test using sonicated antigens of Bacteroides fragilis NCTC 2553 and a B . asaccharolyticus strain, standardised in the laboratory yielded a negative result in the 50 normal sera tested, while it was positive in 24 of 34 (71%) patients with infection due to black pigmented bacteroides and in 10 of 15 (67%) with B . fragilis infection . The microagglutination test (MAT) done in parallel showed a positivity of only 44 and 40 per cent respectively . The CIE test done with B . asaccharolyticus antigen was negative in 87 per cent of patients with infection due to B . fragilis whereas MAT showed cross reactivity to a greater extent. J Clin Immunol, 1991 May, 11(3), 132 - 42 Rheumatoid factor (RF) distribution in periodontal disease; The J et al.; This study investigated the occurrence of an autoantibody, IgM rheumatoid factor, that may result from the chronic inflammation noted in periodontal disease and rheumatoid arthritis . In order to detect IgM-RF, a biotin-avidin ELISA was developed . This assay was found to be sensitive and accurate by testing a rheumatoid arthritis population . The characteristics of this rheumatoid arthritis group were further determined, such that the total serum immunoglobulin concentrations were slightly elevated although within the normal range for IgM, IgG, and IgA; IgG antibody levels were elevated against oral microorganisms of the genus Capnocytophaga, while elevated IgM antibody levels were noted to Bacteroides species . In a population of 260 subjects of which 171 were periodontal disease patients, 16 of 171 (9.4%) were seropositive for IgM-RF, of which the predominant disease types were advanced destructive periodontitis and adult periodontitis . For comparison, a random population of seronegative periodontal disease patients was constructed that was matched for sex and approximate age to the seropositive group . The total immunoglobulin levels of the two groups were not significantly different and the means of both were slightly lower than the rheumatoid arthritis group . When the antibody profiles of the two periodontal disease populations were compared it became evident that the RF-positive group showed IgM and IgG antibody that was significantly elevated to Capnocytophaga species and F . nucleatum . Therefore, the chronic inflammation associated with periodontitis appears to increase significantly the formation of IgM-RF; however, there does appear to be a relationship between IgM-RF and elevated antibody to selected oral microorganisms. J Antimicrob Chemother, 1991 May, 27(5), 599 - 606 Meropenem: in-vitro activity and kinetics of activity against organisms of the Bacteroides fragilis group; Garcia-Rodriguez JA et al.; Meropenem was compared with imipenem and nine other antimicrobial agents, against 101 strains of the Bacteroides fragilis group . Meropenem was active against all strains tested, and its activity was similar to, and in many cases better than, that of imipenem . The activity of meropenem was similar to that of metronidazole, and greater than that of the other antimicrobial agents tested . The bactericidal activity of meropenem against B . fragilis was impressive, since the MBC to MIC ratios were no greater than two . The bactericidal activity was confirmed by time-killing curve assays with two strains which showed that meropenem was rapidly bactericidal and reduced the initial inoculum significantly during the first 4-6 h . The postantibiotic effect of meropenem (2-4 h) and a sub-inhibitory concentration of 1/4 x MIC suggested that meropenem interferes with the normal growth of B . fragilis, even when administered concentrations fall below the MIC . MICs of meropenem were affected minimally by the pH of the medium or by an increase in inoculum size . Meropenem continued to have good activity against a B . fragilis strain that had been induced for the production of cephalosporinase . The in-vitro data presented in this paper indicate that meropenem is a promising antimicrobial agent which may be useful in the treatment of problematic mixed infections. Can J Microbiol, 1991 May, 37(5), 368 - 76 The stability of outer-membrane protein and antigen profiles of a strain of Bacteroides intermedius grown in continuous culture at different pH and growth rates; Bowden GH et al.; The stability of the outer-membrane proteins and antigens of a strain of Bacteroides intermedius (VPI 8944 group genotype II) grown in continuous culture at varying pH and growth rates (D = 0.025-0.2 h-1, pH 6.0-7.3) has been measured . The membranes showed nine major proteins (greater than 67-19.55 kilodaltons) and six major antigens (65-28 kilodaltons) . Membrane proteins and antigens were stable under the conditions tested; the major proteins were detected in all membranes, and the antigen profiles tested with different antisera showed maximum similarities of 82-95% . Differences did occur in the amounts of membrane proteins synthesized; cells at high growth rates and those growing on the surfaces in the chemostat showed increased amounts of two proteins (40 and 32 kilodaltons) and possibly novel proteins of 24 and 25 kilodaltons . In addition, these membranes reflected increased synthesis or a change to increased reactivity of antigens between 20.5 and 24 kilodaltons . The results indicate stability of the expression of outer-membrane proteins and antigens in environments of differing pH and under different growth rates . However, the amount of these molecules synthesized can vary, and increases in certain proteins and antigens occur as the growth rate increases and the organisms grow on surfaces. Am J Vet Res, 1991 May, 52(5), 738 - 41 Identity of Bacteroides isolates and previously named Bacteroides spp in clinical specimens of animal origin; Jang SS et al.; During the years 1984 through 1987 2,574 isolates of obligately anaerobic bacteria were isolated from samples submitted for analysis . The most common anaerobic isolates were members of the genus Bacteroides, representing 44.6% of the isolates . Of these, the most commonly isolated identifiable microorganisms were bile-resistant and nonpigmented, belonging to the B fragilis group of Bacteroides . Importantly, obvious predilections for any one species or group of Bacteroides were not apparent for animal or site (condition), except that the proportion of isolates belonging to the nonpigmented, bile-resistant group obtained from the respiratory tract was significantly (P less than 0.005) higher than that not belonging to this group . On the other hand, the proportion of isolates of the non-pigmented, bile-resistant group obtained from abscesses was significantly lower than that not belonging to this group. J Periodontal Res, 1991 May, 26(3 Pt 1), 184 - 90 Serological studies of Porphyromonas (Bacteroides) gingivalis and correlation with enzyme activity; Nagata A et al.; Porphyromonas gingivalis from the human oral cavity was serologically characterized using absorbed and unabsorbed rabbit antisera . The reference strains were ATCC 33277, W50, W83, 381 and hara 1 . The 432 isolates were from periodontal pockets of 63 patients with adult periodontitis . Using sonicated antigens, four serotypes were identified by immunodiffusion tests and immunoelectrophoresis . Each patient harbored only one serotype of P . gingivalis, and serotypes I and IV predominated . The incidence of serotype I was four times higher than that of serotype II, and approximately seven times higher than that of serotype III . The collagenolytic and some proteolytic enzymes of representatives of each serotype were assessed . Although all strains produced these enzymes to some degree, some differences in their levels were observed . Serotype II strains were more collagenolytic than serotypes I or III, and serotype III exhibited lower activities of N-CBz-glycyl-glycyl-arginyl peptidase than other serotypes . Antibiotic sensitivity was also compared with antimicrobial disks, and serotype IV strains exhibited high sensitivity to the four antibiotics used. J Periodontal Res, 1991 May, 26(3 Pt 1), 167 - 75 Measurement of relative avidity of antibodies reactive with Porphyromonas (Bacteroides) gingivalis in the sera of subjects having adult periodontitis; Lopatin DE et al.; Relative avidities of antibodies to Porphyromonas (Bacteroides) gingivalis in the sera of 15 patients having adult periodontitis and 15 healthy subjects were evaluated using an ammonium thiocyanate-dissociated ELISA . Graded concentrations of ammonium thiocyanate were added to a single dilution of serum in order to dissociate low avidity antibody binding to P . gingivalis . The concentration of thiocyanate resulting in 50% reduction in binding (absorbance) was termed the ID50 for that serum . When IgG-class antibodies were examined, the ID50 of anti-P . gingivalis antibodies in the sera of patients was significantly elevated (0.96M vs 0.71M; p less than 0.01, Student's t-test) . In contrast, when IgM-class antibodies were examined no significant differences in ID50 between patients and controls were found for P . gingivalis (0.54M vs 0.53M) . While the ID50 values of patient antibodies were found to be elevated relative to those of healthy controls, comparison with antibodies from rabbits immunized with P . gingivalis and with ID50 values from other human studies suggests that adult humans, in general, produce very low-avidity antibodies to P . gingivalis . It is suggested that the presence of low-avidity antibodies contributes to the pathology associated with periodontal disease. J Bacteriol, 1991 May, 173(9), 2962 - 8 Characterization of a neopullulanase and an alpha-glucosidase from Bacteroides thetaiotaomicron 95-1; Smith KA et al.; Previously, we constructed a gene disruption in the pullulanase I gene of Bacteroides thetaiotaomicron 5482A . This mutant, designated B . thetaiotaomicron 95-1, had a lower level of pullulanase specific activity than did wild-type B . thetaiotaomicron but still exhibited a substantial amount of pullulanase activity . Characterization of the remaining pullulanase activity present in B . thetaiotaomicron 95-1 has identified an alpha(1----4)-D-glucosidic bond cleaving pullulanase which has been tentatively designated a neopullulanase . The neopullulanase (pullulanase II) is a 70-kDa soluble protein which cleaves alpha(1----4)-D-glucosidic bonds in pullulan to produce panose . The neopullulanase also cleaved alpha(1----4) bonds in amylose and in oligosaccharides of maltotriose through maltoheptaose in chain length . An alpha-glucosidase from B . thetaiotaomicron 95-1 was characterized . The alpha-glucosidase was partially purified to a preparation containing three proteins of 80, 57, and 50 kDa . Pullulan and amylose were not hydrolyzed by the alpha-glucosidase . alpha(1----4)-D-Glucosidic oligosaccharides from maltose to maltoheptaose were hydrolyzed to glucose by the alpha-glucosidase . The alpha-glucosidase also hydrolyzed alpha(1----6)-linked oligosaccharides such as panose (the product of the pullulanase II action on pullulan) and isomaltotriose. Vet Microbiol, 1991 May, 27(3-4), 283 - 93 The effect of dissociation of Bacteroides nodosus pili on their efficacy as a protective antigen against ovine footrot; Stewart DJ et al.; Previous studies have shown that pili from homologous Bacteroides nodosus provide protective immunity in sheep against footrot, whereas denatured pilin subunits are ineffective . The aim of the present study was to examine whether pili that were dissociated into pilin subunits under less vigorous, non-denaturing treatment conditions, would provide an effective level of protective immunity . Using the techniques of gel permeation chromatography, light scattering and susceptibility to proteolysis as measures of disruption, it was shown that pili were dissociated either by the neutral detergents n-octyl-beta-D-glucopyranoside (NOG) and Tween 80 or by lowering the pH with 1 M phosphoric acid to pH 2.2 . Circular dichroic spectra indicated, however that the samples were not denatured by these treatments . Electron microscopic monitoring of detergent dissociated material following exhaustive dialysis showed the presence of protein-detergent micelles and "in-line" aggregates which gave the appearance of short fibres . Within these monitored preparations, there was no evidence of native undissociated pili . Pili dissociated by NOG or acid were tested in protection trials and shown to provide protective immunity, although agglutination titres of serum taken from the vaccinated sheep were significantly lower than those of animals inoculated with intact pili. Biochem Biophys Res Commun, 1991 Apr 15, 176(1), 505 - 10 Effects of a fecapentaene on protein kinase C; Hoshina S et al.; Protein kinase C (PKC) is a Ca2(+)- and phospholipid-dependent serine and threonine protein kinase which binds and is activated by tumor promoters such as the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA) . PKC can be activated in vitro by phosphatidylserine (PS) plus Ca2+ . We report here that the compound fecapentaene-12 can replace the requirement for PS in the activation of PKC by Ca2+ . In addition, at low concentrations fecapentaene-12 can enhance the activation of PKC by Ca2+ and PS . It can also either enhance or inhibit activation of PKC by the tumor promoter teleocidin, depending on the assay conditions . These results are of interest since fecapentaene is known to be a potent mutagen that is produced by Bacteroides species present in the lumen of the human colon . The present studies raise the possibility that this compound might also play a role in colon cancer by altering the activity of PKC. J Dent, 1991 Apr, 19(2), 92 - 6 Evaluation of acrylic strips containing amoxycillin with clavulanic acid for local drug delivery; Abu Fanas SH et al.; The in vitro release of amoxycillin with clavulanic acid from acrylic strips at initial concentrations of 30, 40 and 50 per cent w/w was monitored using a double-beam ultraviolet spectrophotometer and compared with release of tetracycline hydrochloride . Highest levels of the antibacterial agents were released during the first 24 h period . Therapeutic levels of the drugs continued to be released during the subsequent 9 day period and were shown to be biologically active . Furthermore, for amoxycillin with clavulanic acid, an initial concentration of 40 per cent gave the highest level of release on day 10; while, for tetracycline, 50 per cent provided the highest level of release . Local application of 40 per cent amoxycillin with clavulanic acid incorporated into acrylic strips placed in periodontal pockets in patients with established periodontitis produced a marked change in the subgingival microflora as monitored by dark-field microscopy and cultural techniques . These changes in the subgingival flora were concomitant with elimination of bleeding on probing at the treated sites and were still evident 3 weeks after removal of the acrylic strips . The sensitivity of Bacteroides gingivalis (syn . Porphyromonas gingivalis) and Bacteroides intermedius (syn . Prevotella intermedia) isolated before and after treatment to amoxycillin with clavulanic acid remained unchanged. J Periodontol, 1991 Apr, 62(4), 247 - 57 Effects of metronidazole on periodontal treatment needs; Loesche WJ et al.; Periodontitis, a common cause of tooth loss in adult populations, is an inflammatory response to the overgrowth of anaerobic organisms such as spirochetes and bacteroides and, in some cases, micro-aerophilic organisms in the subgingival plaque . In the present investigation, using a double-blind clinical design, we sought to determine whether 1 week of metronidazole treatment plus debridement of the tooth surfaces was superior to 1 week of placebo treatment plus debridement (positive control) in reducing the subsequent amount of periodontal surgery given to the patients . Thirty-nine patients were randomly assigned to either the metronidazole or placebo (positive control) groups . All patients were given the necessary scaling and root planing and were unsupervised in their usage of the medication . After the completion of this treatment, they were reexamined and it was found that the metronidazole regimen caused a significant reduction in surgical needs of about 5 teeth per patient compared to the positive control (difference before and after treatment 8.3 +/- 6.8 teeth metronidazole versus 2.9 +/- 4.8 positive control, P = 0.007) . The difference between groups was maintained during the 2 to 3 years' recall period . Metronidazole had a significant effect on the site specific reduction of spirochetes: 90% of the sites in the metronidazole group versus 64% in the positive-control group had a decrease in the percentage of spirochetes (P less than 0.05) . We conclude that systemic metronidazole given 250 mg tid for 7 days in conjunction with debridement of the tooth surfaces can significantly reduce the need for periodontal surgery compared to the standard regimen which included only debridement. Clin Orthop, 1991 Apr, (265), 297 - 301 Anaerobic osteomyelitis . A new experimental rabbit model; Johansson A et al.; Experimental studies of osteomyelitis have been hampered by methodologic problems . For inducing experimental anaerobic osteomyelitis, the medullary cavity of the proximal tibial metaphysis of five New Zealand white rabbits was excavated and filled with a polyvinyl alcohol sponge . On the right side, 1 ml of a suspension containing Bacteroides fragilis (10(7) colony-forming units/ml) was injected, while on the left side, Ringer's solution was used as a control substance . Within five weeks, all animals developed clinical signs of osteomyelitis . The findings were verified by roentgenograms and bone scans . There was a significant rise in titers against the inoculated B . fragilis strain in every rabbit, and when killed at 18 weeks after the bacterial inoculation cultures containing the inoculated strain were obtained from all animals . No other bacterial strains were isolated . With one exception, cultures were positive in samples from both the inoculated and the control side, indicating hematogenous seeding . In one animal, the cultures from the inoculated side were negative, whereas on the control side, there was significant growth of the inoculated strain . Histologic examination of the infection sites showed low-grade chronic osteitis . In contrast to previous studies, which have indicated severe difficulty in obtaining a single-strain anaerobic osteomyelitis, the present method gives a high infection rate with reproducible immunologic, roentgenographic, and histologic reactions. Infect Immun, 1991 Apr, 59(4), 1255 - 63 A novel mouse model to study the virulence of and host response to Porphyromonas (Bacteroides) gingivalis; Genco CA et al.; We describe here the development of a mouse subcutaneous chamber model that allows for the examination of host-parasite interactions as well as the determination of gross pathology with Porphyromonas (Bacteroides) gingivalis challenge . When inoculated into stainless-steel chambers implanted subcutaneously in female BALB/c mice, P . gingivalis W83, W50, and A7436 (10(8) to 10(10) CFU) caused cachexia, ruffling, general erythema and phlegmonous, ulcerated, necrotic lesions, and death . P . gingivalis W50/BEI, HG405, and 33277 (10(10) CFU) produced localized abscesses in the mouse chamber model with rejection of chambers at the injection site . Analysis of chamber fluid from 33277-, HG405-, and W50/BEI-infected mice by cytocentrifugation revealed inflammatory cell debris, polymorphonuclear leukocytes, and high numbers of dead bacteria . In contrast, fluid from A7436-, W50-, and W83-infected mice revealed infiltration predominantly of polymorphonuclear leukocytes and live bacteria . Bacteria were found primarily associated with polymorphonuclear leukocytes in the fluid from W50-, HG405-, and W83-infected mice but not from A7436-infected mice . Viable isolates were recoverable from the chamber fluid through day 3 for W50/BEI, day 5 for 33277, day 6 for HG405, day 7 for W50, day 14 for W83, and day 26 for A7436 . All strains induced a systemic immunoglobulin G response in serum and chamber fluid samples . The use of this model will allow us to examine the virulence of P . gingivalis as defined by the interaction of host response to localized infection with P . gingivalis. Oral Microbiol Immunol, 1991 Apr, 6(2), 81 - 7 DNA probe detection of Eikenella corrodens, Wolinella recta and Fusobacterium nucleatum in subgingival plaque; Lippke JA et al.; This cross-sectional study used species-specific DNA probes to examine subgingival plaque specimens for the presence of Eikenella corrodens, Wolinella recta, and Fusobacterium nucleatum in adults with untreated periodontitis or gingivitis and in healthy controls . W . recta and F . nucleatum were more prevalent in diseased sites from the periodontitis group when compared with the controls (81% vs 22% and 83% vs 20% respectively) . E . corrodens was detected in 62% of the control sites and 81% of the periodontitis sites . Because the control sites commonly contained this organism, E . corrodens may not be useful in differentiating between health and disease . In addition, the relationship between the prevalence of W . recta and F . nucleatum and the prevalence of the established periodontal pathogens, Actinobacillus actinomycetemcomitans, Bacteroides intermedius and Bacteroides gingivalis, was examined . Positive detection of W . recta and F . nucleatum correlated closely with the presence of A . actinomycetemcomitans, B . intermedius and B . gingivalis . Therefore, W . recta and F . nucleatum do not appear to be unique indicators of periodontal disease. Oral Microbiol Immunol, 1991 Apr, 6(2), 111 - 4 Rapid antimicrobial resistance screening method for Bacteroides intermedius; Calsina G et al.; The purpose of the study was to validate a rapid resistance screening (RRS) method for antimicrobial susceptibility testing of a selected periodontopathic microorganism using the standard broth dilution method as a control . Twenty-five subgingival plaque samples from gingivitis or periodontitis sites were plated on Trypticase soy agar supplemented with 5% rabbit blood with antibiotic discs (RRS method) and without (control) . The antibiotics tested were: Augmentin, clindamycin, erythromycin, metronidazole, penicillin G and tetracycline hydrochloride . Bacteroides intermedius isolated from both groups of plates were placed onto antibiotic supplemented Trypticase soy broth . The antibiotic susceptibilities of B . intermedius isolated from the plates with antibiotic discs and the standard broth method were compared . The results showed high sensitivity and predictability for the RRS method compared with the control . The percentage of agreement was: 100% for Augmentin 30 micrograms, clindamycin 2 micrograms and tetracycline 30 micrograms; 96% for erythromycin 15 micrograms, metronidazole 80 micrograms and penicillin 10 IU; 92% for penicillin 2 IU; 88% for erythromycin 2 micrograms and 84% for tetracycline 5 micrograms . The results of this study document the feasibility of the RRS method for testing antimicrobial resistance of whole samples if its efficacy can be demonstrated for other bacteria . This method may be a quick and useful test for the periodontal practitioner in determining the antibiotic susceptibility of periodontal plaque pathogens. J Bacteriol, 1991 Apr, 173(8), 2581 - 9 Adhesion of Actinomyces viscosus to Porphyromonas (Bacteroides) gingivalis-coated hexadecane droplets; Rosenberg M et al.; Interbacterial adhesion (coadhesion) is considered a major determinant of dental plaque ecology . In this report, we studied several aspects of the adhesion of Porphyromonas (Bacteroides) gingivalis to hexadecane in order to use the liquid hydrocarbon as a convenient substratum for coadhesion assays . Washed suspensions of hydrophobic P . gingivalis 2561 cells were vortexed with hexadecane to yield highly stable cell-coated droplets . Kinetics of coadhesion between Actinomyces viscosus cells and P . gingivalis-coated hexadecane droplets (PCHD) was subsequently studied . Aliquots of PCHD were added to A . viscosus suspensions, and the mixtures were gently rotated . Avid adhesion of A . viscosus cells to the immobilized P . gingivalis layer could be readily measured by the decrease in turbidity in the aqueous phase, following phase separation . Despite the ability of A . viscosus cells to adsorb to hexadecane following vigorous mixing, gentle mixing did not appreciably promote adhesion to bare hexadecane . Moreover, extensive microscopic examinations revealed that A . viscosus cells adhered exclusively to the bound P . gingivalis cells rather than to exposed areas of hexadecane . Coadhesion of A . viscosus to the PCHD appeared to follow first-order kinetics, attaining 80% levels within 30 min . Electron micrographs revealed A . viscosus cells adhering to the P . gingivalis cell layer adsorbed at the hexadecane-water interface . Interestingly, P . gingivalis cells did not appear to penetrate the hexadecane . A viscosus mutants lacking type 1 or type 2 fimbriae or both were still able to bind to the PCHD . No obvious correlation was observed between relative hydrophobicity of A . viscosus strains and their binding to PCHD . However, defatted bovine serum albumin, an inhibitor of hydrophobic interactions, was the most potent inhibitor among those tested . The data suggest that this approach provides a simple, quantitative technique for studying kinetics of bacterial coadhesion which is amenable to both light and electron microscopic observation. J Clin Microbiol, 1991 Apr, 29(4), 723 - 5 Chronic conjunctivitis caused by oral anaerobes and effectively treated with systemic metronidazole plus amoxicillin; van Winkelhoff AJ et al.; In this study, we report on a case of refractory, unilateral anaerobic conjunctivitis . The predominant anaerobic flora consisted of Prevotella intermedia (formerly Bacteroides intermedius) and Peptostreptococcus micros . By using the technique of restriction endonuclease fingerprinting of genomic DNA, it was shown that the P . intermedia likely originated from the oral cavity . Topically applied antibiotics had failed to suppress the infection in the past . Successful treatment was achieved after systemic administration of metronidazole plus amoxicillin. Antonie Van Leeuwenhoek, 1991 Apr, 59(3), 191 - 8 Fermentation of L-tartrate by a newly isolated gram-negative glycolytic bacterium; Janssen PH; Enrichments on L-tartrate from a freshwater lake sediment yielded a pure culture of anaerobic bacterium designated strain 16Lt1 . The rod-shaped organism was motile, did not form spores, and had a gram-negative wall structure . No cytochromes were detected . The mol % G + C of the DNA was 58 . The new strain was microaerotolerant, and grew optimally at 30 degrees C and neutral pH in freshwater medium . A wide range of carbohydrates was fermented, with formate, acetate, ethanol, lactate and succinate being the end-products detected . L-tartrate and citrate were fermented to formate, acetate and CO2 . L-tartrate was fermented by the dehydratase pathway, and glucose by the Embden-Meyerhof-Parnas pathway . Fumarate was reduced, but nitrate, sulfate, sulfur and thiosulfate were not used as terminal electron acceptors . Glucose metabolism was constitutive, whereas L-tartrate-degrading activity was inducible . When glucose and L-tartrate were both present as substrates, growth was diauxic with glucose being metabolized first . The growth rate and growth yield were higher on glucose than on L-tartrate . Strain 16Lt1 has been deposited with the Deutsche Sammlung von Mikroorganismen as 'Bacteroides' sp . DSM6268. Enferm Infecc Microbiol Clin, 1991 Apr, 9(4), 214 - 8 {Evolution of the sensitivity of Bacteroides group fragilis at the Sevilla University Hospital (1983-1987)}; Borobio MV et al.; The evolution of antimicrobial susceptibility of Bacteroides fragilis over a five year period is described . We have studied 30 selected strains isolated each year at the University Hospital of Sevilla (total: 150 strains) . We did not find any resistant strain to chloramphenicol, metronidazole or imipenem . Resistance to piperacillin (8%) and cefoxitin (13%) remain constant over the study period . Resistance to cefmetazole, cefotaxime, mezlocillin, ofloxacin, clindamycin and moxalactam ranges from 24% to 37% . A rise in the percentage of resistant strains to ticarcillin (from 17% to 30%) and ceftizoxime (from 0% to 40%) was also seen during the study period . Bacteroides thetaiotaomicron was the overall more resistant species, and B . fragilis the more sensitive. Roum Arch Microbiol Immunol, 1991 Apr-Jun, 50(2), 95 - 108 Detection of Bacteroides fragilis group by immunofluorescence; Radu I et al.; The following strains: B . fragilis subspecies thetaiotaomicron (A); B . fragilis subspecies fragilis strain E-1, E-2, M, St., Se., Ni., 8, 16; B . fragilis subspecies distasonis 145 (D) were serologically studied by immunofluorescence as compared to agglutination . Anti-B . fragilis sera titration by immunofluorescence (IF) reaction, as compared to agglutination reaction in tube, was more sensitive (2-16 times higher titers), specific and reproducible . Among the organisms from B . fragilis group, species, subspecies and even train specificity was noticed . Also, the possibility for rapid identification of anaerobic organisms, belonging to B . fragilis group, in pathologic products obtained from experimentally infected animals (mice and rats), by IF reaction, in comparison with classic methods (anaerobic cultures and biochemical determinations) was studied . Of 87 studied animals, 61 proved positive by cultures and 59 by IF; 56 animals were shown positive and 23 animals proved negative by both methods (intermethods concordance in 79 cases) . Statistical analysis of IF results provided the following: method sensitivity (detection capacity of real-positive cases)-91.80%; method specificity (detection capacity of real-negative cases)-88.46%; false-positive cases-11.53%; false-negative cases-8.19% . Immunofluorescence proved specific, sensitive, practical and rapid method detection of non-sporulated anaerobic organisms species and subspecies belonging to Bacteroides fragilis group. Can J Vet Res, 1991 Apr, 55(2), 117 - 20 Monoclonal antibodies against pili of serologically distinct Bacteroides nodosus; Gradin JL et al.; Several monoclonal antibodies (McAbs) against pili of Bacteroides nodosus were examined to determine their reactivity with 11 different serotypes . One McAb was identified by enzyme-linked immunosorbent assay (ELISA) analysis that bound to nine of the 11 serotypes and another that bound to the remaining two serotypes tested . In addition, some McAbs demonstrated specificity for a single serotype, while others displayed specificities for up to five other serotypes . Comparison of immunoblot analysis with the ELISA revealed that the former method was not as sensitive in that all McAbs positive by the ELISA, were not positive by immunoblot . Possible explanations of these findings are discussed . There appear to be several antigenic determinants on B . nodosus pili and considerable sharing of these determinants between pili types . The 11 serotypes analyzed by the McAbs in this report are representative of all 20 US serotypes as well as the A-set and D-set categories of Australia . Therefore, the two epitopes recognized by two of the McAbs reported herein encompass all of the currently characterized B . nodosus serotypes and may provide a basis for bivalent vaccines efficacious for all types of B . nodosus induced footrot in sheep. Dig Dis Sci, 1991 Apr, 36(4), 461 - 70 Inflammatory bowel disease induced by combined bacterial immunization and oral carrageenan in guinea pigs . Model development, histopathology, and effects of sulfasalazine; Oestreicher P et al.; A model of experimentally induced inflammatory bowel disease (IBD) featuring colitis, originally devised by Onderdonk and co-workers in guinea pigs, was modified to establish the optimal conditions for ulcer development . Upon varying the time of subcutaneous immunization with Bacteroides vulgatus and concomitant oral administration of acid-degraded iota-carrageenan and viable B . vulgatus, it was found that the optimal times of administering these agents were one to two weeks and five to six days, respectively . Light microscopy of the colon and cecum of the guinea pigs given the optimized treatment for ulcer induction revealed pronounced edema, inflammation, and lesions of the mucosa . Transmission electron microscopy of the mucosa from these animals showed the presence of large numbers of leukocytes in the subepithelial region, the majority being polymorphonuclear neutrophils which possessed large electron-dense granules or rods . Oral administration of 300 mg/kg/day sulfasalazine (salicylazosulfapyridine) for 14 days to guinea pigs given the optimized treatment for ulcer induction failed to reduce the numbers of ulcers or the histopathology gradings and fine structural changes of the mucosal inflammatory changes, but did reduce the symptoms of diarrhea. Oral Microbiol Immunol, 1991 Apr, 6(2), 102 - 6 Variance in recovery of periodontitis-associated bacteria caused by sampling technique and laboratory processing; Wikstrom M et al.; The influence of sampling procedure and of laboratory processing on the recovery of Bacteroides gingivalis, Bacteroides intermedius, and Actinobacillus antinomycetemcomitans from periodontitis sites was evaluated . Thirty-three adult subjects with severe periodontitis participated in the study . In all, 462 samples from 81 sites were examined . The samples were taken using the paper point technique . The cultivations were performed by use of enriched Brucella agar for determination of total colony-forming units and Bacteroides species, and trypticase soy bean agar for determination of A . actinomycetemcomitans . The risk of getting a false negative result was 4% for B . gingivalis, 20% for B . intermedius, and 38% for A . actinomycetemcomitans . It was considerably reduced if duplicate samples were taken . The sampling procedure alone explained up to 98% of the false-negative results. J Am Vet Med Assoc, 1991 Mar 15, 198(6), 1045 - 8 Clinical use of metronidazole in horses: 200 cases (1984-1989); Sweeney RW et al.; Case records of 200 horses treated with metronidazole were reviewed . Horses were treated for respiratory tract infections (90 cases), peritonitis or abdominal abscess (39 cases), celiotomy (49 cases), orthopedic infections (6 cases), and miscellaneous soft tissue infections (16 cases) . Bacteria of the genus Bacteroides were most prevalent (55 of 167 anaerobic isolates) . Metronidazole was always used in combination with other antimicrobial drugs . Only 4 of the 200 horses had signs of adverse effects associated with metronidazole treatment . Those 4 horses had poor appetite that resolved when metronidazole treatment was discontinued. Biochem Biophys Res Commun, 1991 Mar 15, 175(2), 713 - 9 Purification, characterization and immunolocalization of fimbrial protein from Porphyromonas (bacteroides) gingivalis; Sojar HT et al.; Rapid and reproducible method is described here for the purification of the 43 kDa fimbrial protein from P . gingivalis by preferential fractionation in the presence of 1% SDS and 0.2M of a bivalent cation at pH 6.5 . Homogeneity of the purified 43 kDa was confirmed by SDS-PAGE and Western blot analysis using monoclonal and polyclonal antibodies raised against this protein . Amino acid composition and the amino acid sequence of the first 30 amino acid residues of the purified fimbriae are consistent with the composition and sequence predicted from the cloned gene of the fimbrial subunit . Circular dichroism spectra shows high levels of beta-sheet structure . The purified 43 kDa polymer shows fimbriae-like morphology under the electron microscope . Ultrastructural localization of the 43 kDa protein by the immunogold technique revealed specific labeling of the fimbriae with a diameter of approximately 3.5 to 5.0 nm . Localization of this protein suggest that the 43 kDa component is a fimbrial subunit. Tohoku J Exp Med, 1991 Mar, 163(3), 175 - 85 Effect of a platelet activating factor antagonist and antithrombin III on septicemia and endotoxemia in rats; Inoue Y et al.; Disseminated intravascular coagulation (DIC) or renal damage associated with septicemia was induced in rats by ligating the cecum or by injecting endotoxin . In the septicemia model, the number of E . coli and Bacteroides spp in the blood increased concomitantly with an increase of endotoxin . In this model the development of hypercoagulability with mild fibrinolysis was observed . Histopathologic findings in the kidneys, including the formation of microthrombi in the glomeruli and the vacuolization and dilatation of renal tubular cells, suggest the development of mild DIC . In the endotoxin-induced DIC model, both remarkable state of hypercoagulability and fibrinolysis were observed with fibrin thrombi in glomeruli . The administration of the platelet-activating factor antagonist, CV-6209, or of human antithrombin III, ameliorated DIC significantly by limiting the increases in prothrombin time, activated partial thromboplastin time and fibrin degradation products . These agents significantly reduced the deposition of fibrin in the glomeruli and significantly prolonged the survival time of the endotoxin injected rats . These observations suggest that the PAF antagonist CV-6209 and ATIII merit clinical evaluation in the management of DIC caused by septisemia. Infection, 1991 Mar-Apr, 19(2), 101 - 5 Comparative efficacies of ticarcillin, ticarcillin/clavulanic acid, piperacillin and cefoxitin against polymicrobial infections in mice caused by Escherichia coli and Bacteroides fragilis; Beale AS et al.; A model of localised abscess formation was used to establish mixed infections caused by Escherichia coli and Bacteroides fragilis . The beta-lactamase producing, ticarcillin-resistant strains E . coli E96 and B . fragilis VPI 8708 were used to produce one infection, and in another infection, a beta-lactamase hyperproducing strain E . coli 41548 was combined with a ticarcillin-susceptible strain, B . fragilis B3 . Treatment, at doses producing clinically achievable concentrations in mouse serum, began 1 h after inoculation, and continued three times daily for four days . Bacterial numbers in infected tissue were measured at intervals . Against both infections, ticarcillin was ineffective in preventing bacterial growth and abscess formation in all mice . Piperacillin prevented abscess formation in 60% of the mice infected with E . coli E96/B . fragilis VPI 8708, and in 40% of those in the E . coli 41548/B . fragilis B3 group . Therapy with ticarcillin/clavulanic acid or cefoxitin reduced the number of both organisms at the site of infection, and thus prevented abscess formation in 100% treated animals. Int J STD AIDS, 1991 Mar-Apr, 2(2), 102 - 4 Anaerobic vaginosis: study of male sexual partners; Arumainayagam JT et al.; One hundred male sexual partners of women with anaerobic vaginosis (AV) were screened for the presence of sexually transmitted diseases (STD) . Thirty male partners had evidence of non-gonococcal urethritis (NGU), compared to 5 in the control group (P less than 0.05) . Chlamydia trachomatis was isolated from 14 male partners, compared to 3 in the control group . Forty-five male partners required treatment for STDs, compared to 11 in the control group (P less than 0.02) . Nine (40%) male partners with chlamydia-negative NGU were successfully treated with metronidazole alone while 10 required Deteclo in addition . There was no significant association between Bacteroides ureolyticus and chlamydia-negative NGU . Screening of male partners resulted in the treatment of STDs in 62 additional patients who would have otherwise not received treatment . The results suggest that examination of male partners of women with AV results in an increased yield of STD diagnoses. J Appl Bacteriol, 1991 Mar, 70(3), 245 - 52 The hydrolysis of lucerne cell-wall monosaccharide components by monocultures or pair combinations of defined ruminal bacteria; Miron J; The defined ruminal bacterial strains Fibrobacter succinogenes S85, Ruminococcus flavefaciens FD1, Ruminococcus albus 7, Butyrivibrio fibrisolvens D1, and Bacteroides ruminicola GA33 were grown, in monocultures or as combinations of pair strains, on isolated lucerne cell-walls (CW) as the sole carbohydrate substrate . Fibrobacter succinogenes S85 was the dominant strain determining extent of CW hydrolysis in all combinations with S85 . The hydrolysis of cellulose, xylan, hemicellulose side-sugars, and total CW monosaccharides by pure S85 were: 58.8, 47.3, 66.9 and 57.0%, respectively . The strains combination S85 plus D1 comprised the highest complementary effect, increasing significantly the hydrolysis of cellulose and total CW monosaccharides by 16% and 13%, respectively, above the values obtained by pure S85 . This complementation was expressed also in growth pattern of bacteria . The monocultures of FD1, D1 and GA33 had very little hydrolytic effect on lucerne cellulose, but higher effects on xylan and hemicellulose side-sugars . The combinations D1 plus GA33 and 7 plus GA33 were complementary in the hydrolysis of all CW polysaccharides . The combinations FD1 plus D1, FD1 plus GA33, and 7 plus D1 were complementary only with respect to hemicellulose hydrolysis . On the other hand, the cellulolytic combinations S85 plus FD1, S85 plus 7 and FD1 plus 7 demonstrated negative interactions in lucerne CW polysaccharides hydrolysis . Under scanning electron microscopy (SEM), S85 comprised the most dense layer of bacterial cell mass attached to and colonized on CW particles . The cell surface topology of the cellulolytic strains S85, FD1 and 7 attached to CW particles was specified by a coat of characteristic protuberant structures. J Appl Bacteriol, 1991 Mar, 70(3), 216 - 20 Rapid differentiation of the species of the genus Bacteroides sensu stricto by capillary gas chromatography of cellular carbohydrates; Engelhard E et al.; Whole-cell hydrolysates of Bacteroides fragilis, the type species of the genus Bacteroides Castellani and Chalmers 1919, and the genetical closely related species B . vulgatus, B . ovatus, B . eggerthii, B . distasonis, B . uniformis, B . thetaiotaomicron, B . stercoris, B . merdae, and B . caccae were used to determine characteristic carbohydrate patterns by capillary gas chromatography . On the basis of the chemical derivatization of the carbohydrates seven characteristic peaks for peracetylated aldononitriles and nine characteristic peaks for peracetylated o-methyloximes were selected from the carbohydrate fingerprints of the reference strains to prepare a dichotomous identification key . The classification of an unknown strain supposed to belong to the formerly called 'Bacteroides fragilis group' is possible with this key . Some of the advantages of the technique were that the identification of Bacteroides fragilis-like strains requires only 4-5 h after primary isolation and that the bacteria can be exposed to oxygen because viability of the organisms is not necessary . Sophisticated anaerobic techniques can therefore be avoided for identification. J Periodontol, 1991 Mar, 62(3), 197 - 202 A randomized, placebo-controlled trial of doxycycline: effect on the microflora of recurrent periodontitis lesions in high risk patients; Kulkarni GV et al.; Twenty-seven patients with a recent history of periodontal abscesses and/or loss of gingival attachment level (GAL) despite active periodontal therapy were enrolled in a double-blind, randomized, placebo-controlled trial . Clinical measurements and subgingival scaling were performed every 2 months . When a site exhibited greater than or equal to 2 mm loss of GAL or a periodontal abscess, patients were administered either doxycycline at a dosage of 200 mg to start and 100 mg per day for 3 weeks, or a placebo . Clinical measurements of GAL and microbial analysis of subgingival plaque at study and control sites were made at the time of active disease and at intervals of 1 week and 7 months after completion of the drug regime . Plaque samples were screened for the presence of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Bacteroides intermedius (Bi), Eikenella corrodens (Ec) and Fusobacterium nucleatum (Fn) by indirect immunofluorescence antibody technique and for spirochetes (Sp) using Ryu's stain . Based on presence or absence analysis of the sum scores of the 6 pathogens, both the placebo (n = 10) and the doxycycline groups (n = 17) exhibited similar scores at the time of detection of active disease (mean placebo = 2.38 +/- 0.32; mean doxycycline = 2.95 +/- 0.27; P = 0.18) . One week after treatment, the probability of detection was unchanged in the placebo group (mean placebo = 3.14 +/- 0.47), but was significantly reduced in the doxycycline group (mean doxycycline = 1.77 +/- 0.26; P = 0.0002) . Study (active) sites exhibited scores 2 to 3 times higher than control (inactive) sites before doxycycline treatment.(ABSTRACT TRUNCATED AT 250 WORDS) Ann Surg, 1991 Mar, 213(3), 253 - 60 The peritoneal environment during infection . The effect of monomicrobial and polymicrobial bacteria on pO2 and pH; Sawyer RG et al.; Intraperitoneal (IP) abscesses frequently are composed of aerobes and anaerobes, and, in experimental models, a particulate adjuvant . The environmental changes effected by these components, either singularly or in combination, have not been well defined . The IP pO2, pH, and recoverable bacteria from the peritoneum of rats were quantified over 6 hours during simple aerobic and anaerobic infections and during mixed peritonitis with and without a sterile feces-barium sulfate adjuvant (SFA) . Fourteen groups were studied, receiving intraperitoneally, at time of oxygen probe placement, 1 mL normal saline (control), Escherichia coli (EC), Bacteroides fragilis (BF), SFA alone, or a mixture of EC and BF, EC and SFA, BF and SFA, or EC, BF, and SFA . Control animals exhibited a stable IP pO2 and pH during 6 hours . In monomicrobial EC peritonitis, inocula well below the LD50 produced an increased IP pO2 and reduced arterial-peritoneal gradient (APG), with a stable IP pH . By 6 hours lethal doses of EC produced a dramatic decline in IP pO2, with no change in arterial pO2 as well as acidic IP and arterial pHs . Simple BF peritonitis caused no or minor elevations in IP and arterial pO2 with no change in pH . During mixed infections a significant decline in the IP pO2 and pH at 6 hours in those groups infected with both SFA and EC of a moderate, normally sublethal inoculation was observed, while arterial pO2 was unchanged and arterial pH was decreased only slightly . Concomitantly there was a significant increased number of aerobic bacteria in those groups with SFA as adjuvant compared to similar inocula without SFA . This study demonstrates the complex interactions of bacteria, sterile particulate adjuvant (SFA), and the host peritoneum . It suggests that the combination of SFA and aerobic bacteria alter the peritoneal environment to one permitting anaerobic growth and promoting abscess formation. J Infect Dis, 1991 Mar, 163(3), 664 - 7 Preexposure of the peritoneum to live bacteria increases later mixed intraabdominal abscess formation and delays mortality; Sawyer RG et al.; Intraabdominal infections are a major source of morbidity and mortality for the trauma and postoperative patient . Transient peritoneal contamination with bacteria after either intentional or unintentional violation of the gut are common . The effect of this intermittent antigen exposure upon later formation of intraabdominal abscesses is unclear . Previous experiments by others have demonstrated that repeated exposure to Bacteroides fragilis capsular polysaccharide can induce a T lymphocyte-mediated immunity to subsequent induction of pure B . fragilis abscess formation . In a murine mixed intraabdominal abscess model, preexposure to live Escherichia coli, B . fragilis, or both increased the number of later abscesses and in some cases their bacterial composition . Further, immunization with E . coli alone increased late mortality without altering overall mortality . These data suggest that the alterations of immune function produced by live, transient bacteria upon subsequent mixed intraabdominal abscess induction result in fundamentally different consequences from those observed after specific polysaccharide antigen exposure and subsequent monomicrobial abscess induction. Indian J Med Res, 1991 Mar, 93, 98 - 102 Rapid identification of clinically important bacteroides by coagglutination method; Lalitha MK et al.; A coagglutination technique using indigenous reagents was applied for the rapid identification of Bacteroides fragilis and the black pigmented bacteroides group, using colony suspensions . All the 58 strains of B . fragilis and 42 strains of black pigmented bacteroides tested could be correctly identified by this method . The specificity of the coagglutination reagent was confirmed by the absence of cross reactivity with the related species of bacteroides, viz., B . distasonis, B . ovatus, B . vulgatus and B . thetaiotaomicron as well as other anaerobic and aerobic bacteria . A panel of four antisera against B . fragilis was required for correct identification of the strains tested, indicating the presence of multiple serotypes . On the other hand, all 42 strains of black pigmented bacteroides tested could be identified, using a single reagent as these strains appeared to have no antigenic type variants. Zhonghua Kou Qiang Yi Xue Za Zhi, 1991 Mar, 26(2), 70 - 2, 126 {The correlation of black-pigmented bacteroides spp to symptoms associated with apical periodontitis}; Chen H; The quantitative analysis of the incidence of black-pigmented Bacteroides (B.P.B.) spp . in 80 human dental root canal infections (56 with acute symptoms and 24 clinically asymptomatic) in 79 adults were studied . Altogether 101 strains including 7 species of B . P . B . were identified . It was found that the infection rate of B . P . B . in symptomatic group (192.86%) was higher than that in asymptomatic group (41.67%) . The means of quantity of cultivable B . P . B . (CFU/ml) and percentage of B.P.B . (CFU/ml) in total CFU/ml of bacteria were not significant . But the percentage of asacchrolytic B.P.B . species in B.P.B . positive samples in symptomatic group (73.08%) was higher than that in B.P.B . positive samples in asymptomatic group (40%) . These results suggest that there is a close correlation between symptoms and the asacchrolytic species of B . endodontalis and B . gingivalis. Mol Microbiol, 1991 Mar, 5(3), 543 - 60 Organization of the fimbrial gene region of Bacteroides nodosus: class I and class II strains; Hobbs M et al.; The fimbrial subunit genes of Bacteroides nodosus may be divided into two distinct classes, based on the sequence of the major subunit gene fimA (accompanying paper--Mattick et al., 1991) . The genetic organization of the fibrial gene region in these two classes is also distinct . Upstream of fimA in both classes in opposite transcriptional orientation is the gene aroA which encodes amino acid biosynthetic enzyme 5-enolpyruvylshikimate-3-phosphate synthase . However, downstream of fimA the two classes are quite different until homology is restored at a bidirectional transcription termination signal separating the fimbrial operon from a gene clpB, which appears to encode the regulatory subunit of an ATP-dependent protease . Between aroA and clpB class I strains contain, apart from fimA, only one other gene (fimB) . Sequence and polymerase chain reaction analyses indicate that fimB does not have a separate promoter but rather is co-transcribed with fimA at a level attenuated by the strength of the transcription termination signal in the intergenic region . In class II strains fimA is followed by a more extended region containing three genes, which appear to have the same transcriptional arrangement as fimB . The second of these genes (fimD) may represent a functional analogue of fimB although there is no close sequence homology . The first gene (fimC) has no obvious similarity to either fimB or fimD . Beyond fimD, at the 3' end of the class II-specific region, is a variant fimbrial subunit gene (fimZ) which is virtually identical in serogroups D and H and which appears to represent a duplicate, possibly redundant, gene closely related to the progenitor of the more divergent structural subunit fimA gene found in these strains . Comparisons of the predicted fimZ product with those of fimA in class I and class II strains, as well as of the boundaries of the class-specific regions, suggest that the class II sequences evolved in another type 4 fimbriate species and were subsequently substituted in the B . nodosus genome by lateral transfer . Analysis of the sequences flanking fimA in different strains indicates that recombinational exchange of both fimA and the entire operon has also occurred between strains, and is possibly a mechanism for disseminating structural diversity in the population. Gene, 1991 Mar 1, 99(1), 115 - 9 Sequence of fimbrial subunit-encoding genes from virulent and benign isolates of Dichelobacter (Bacteroides) nodosus; Billington SJ et al.; Both virulent and benign isolates of the ovine pathogen Dichelobacter (Bacteroides) nodosus produce polar fimbriae which have been implicated in twitching motility . The fimbrial subunit-encoding genes from two virulent and two benign serogroup-B isolates of D . nodosus were cloned and sequenced . Analysis of the deduced amino acid (aa) sequences of these subunits indicated the presence of substitutions that appeared to correlate with the virulence phenotype . However, these aa substitutions were located in variable regions of the protein where they are unlikely to alter the functional properties of the fimbriae . The aa sequences of the serogroup-B subunits had a very high level (91-95%) of similarity, particularly at the N terminus, where the conserved region extended up to aa 61 . Specific aa substitutions within the subunit of one isolate may reflect its