Clin Infect Dis, 1993 Jun, 16 Suppl 4, S339 - 43 Bactericidal activity of selected antimicrobial agents against Bilophila wadsworthia and Bacteroides gracilis; Baron EJ et al.; Bactericidal assays of Bacteroides gracilis (six strains) and Bilophila wadsworthia (12 strains) in brucella broth with appropriate supplements were performed by the time-kill kinetic method . Antimicrobial agents tested were ampicillin/sulbactam (final concentrations, 16/8 micrograms/mL), ticarcillin/clavulanate (128/2 micrograms/mL), imipenem (8 micrograms/mL), cefoxitin (32 micrograms/mL), chloramphenicol (16 micrograms/mL), clindamycin (4 micrograms/mL), and metronidazole (16 micrograms/mL) . Although all antimicrobial agents tested inhibited growth of all Bilophila strains during the first 24 hours, bactericidal activity was variable; only metronidazole was uniformly bactericidal . Most strains of Bilophila showed 1-2 log increases in growth at 6 hours with clindamycin and chloramphenicol . With chloramphenicol, some Bilophila strains tested showed regrowth starting at 30 hours . B . gracilis strains were generally more susceptible to all agents tested . Metronidazole, ticarcillin/clavulanate, chloramphenicol, and imipenem were most active . Several strains of B . gracilis were not killed by ampicillin/sulbactam, clindamycin, or cefoxitin . Activity was variable among strains and antimicrobial agents. Clin Infect Dis, 1993 Jun, 16 Suppl 4, S256 - 62 Bacteriology of anaerobic pleuropulmonary infections: preliminary report; Marina M et al.; A retrospective bacteriologic study of anaerobic pleuropulmonary infections diagnosed at the Wadsworth Veterans Affairs Medical Center between 1976 and 1991 was performed . There were 116 specimens from 110 patients . Available strains were reexamined using the latest tests and taxonomic schemes . Pleural fluid was believed to provide the most reliable specimen; cultures yielded an average of 3.0 anaerobes and 0.6 nonanaerobes per specimen . The most commonly encountered anaerobes were pigmented Prevotella species, nonpigmented Prevotella species, Fusobacterium nucleatum, Peptostreptococcus species, and Bacteroides species . Thirty percent of the anaerobic gram-negative rods were beta-lactamase producers. Clin Infect Dis, 1993 Jun, 16 Suppl 4, S248 - 55 Anaerobic bacterial infections of the lung and pleural space; Bartlett JG; In 193 reviewed cases of pleuropulmonary infections involving anaerobic bacteria, the predominant clinical syndromes were aspiration pneumonia, lung abscess, and empyema . Most patients had an indolent infection with tissue necrosis (abscess or bronchopulmonary fistula) at initial presentation . Nevertheless, many had a more fulminant disease course resembling that of pneumococcal pneumonia . Transtracheal aspiration was the procedure most commonly used to obtain uncontaminated specimens for anaerobic culture; since this procedure now is seldom employed, pulmonary infections due to anaerobes rarely have an etiologic diagnosis at present . The dominant pathogens are Peptostreptococcus, Bacteroides, Prevotella, and Fusobacterium species . Although clindamycin is widely considered to be the antibiotic of choice, proper therapeutic trials would probably prove many antibiotics to be effective for the treatment of anaerobic pleuropulmonary infections. Clin Infect Dis, 1993 Jun, 16 Suppl 4, S200 - 2 Stimulation of B lymphocytes by lipopolysaccharides from anaerobic bacteria; Hofstad T et al.; Lipopolysaccharides (LPSs) from anaerobic gram-negative bacteria, including those of low endotoxic activity that are isolated from Bacteroides, Prevotella, and Porphyromonas are potent inducers of DNA replication and polyclonal immunoglobulin production in murine B lymphocytes . The activation is dose-dependent and T cell-independent . Replication of DNA and production of immunoglobulins were also stimulated by lipid A and by the LPS heteropolysaccharide that were isolated by mild acid hydrolysis of the LPSs of Bacteroides fragilis and Fusobacterium nucleatum . Combinations of LPS, lipid A, and acid-degraded polysaccharide amplified the blastogenic response . Antibodies that react with the polysaccharide part of LPSs isolated from members of the Bacteroidaceae are present in healthy human serum. Clin Infect Dis, 1993 Jun, 16 Suppl 4, S190 - 4 Interactions between leukocytes and anaerobic bacteria in polymicrobial surgical infections; Rotstein OD; Anaerobic bacteria are frequent isolates from the mixed bacterial flora of surgical infections . Recent studies have defined an important role for these microorganisms in determining the overall virulence of these infections . One mechanism underlying this effect is the ability of anaerobes to interact with leukocytes, resulting in impairment of host defense mechanisms . This review will address two such mechanisms . First, short-chain fatty acids generated by Bacteroides species during the stationary phase of culture have been shown to cause global impairment of the microbicidal activity of neutrophils . The observation that inhibition was maximal at low extracellular pH led to the finding that the fatty acids mediated this effect by shuttling protons from the extracellular to cytoplasmic space, thereby causing intracellular acidification with resultant cell dysfunction . Second, local fibrin deposition at the site of infection appears to impair bacterial clearance . Interaction between Bacteroides species and peritoneal macrophages has been shown to induce cell-associated procoagulant activity . This may represent another potential mechanism by which anaerobes impair leukocyte function and predispose to abscess formation. Minerva Stomatol, 1993 Jun, 42(6), 301 - 9 Clinical aspects and microbiology of HIV-associated periodontal lesions; Piluso S et al.; This study examines the clinical aspects of HIV-associated periodontal lesions and the prevalence of periodontal pathogens . Subgingival plaque samples were taken from 55 subjects in six study groups: 1) HIV-seropositive patients with gingivitis, 2) necrotizing gingivitis, 3) periodontitis or 4) with health periodontium, 5) patients with rapidly progressive periodontitis or 6) periodontally healthy in whom there was no evidence of HIV infection . Among HIV-positive patients there was a majority (66%) of intravenous drug users . We detected more Bacteroides intermedius, B . buccae and B . oralis in HIV-infected patients with periodontal lesions and in HIV-negative subjects with rapidly progressive periodontitis than in the other groups . High levels of Spirochetes were recovered in both HIV associated necrotizing gingivitis and periodontitis . The results indicate that there is a similarity in the microbiological profile of HIV-associated gingivitis, necrotizing gingivitis, periodontitis and rapidly progressive periodontitis of HIV-negative subjects although significant differences in the clinical aspects of the lesions and in the immune status of the host have been observed. Mikrobiol Z, 1993 Jun-Aug, 55(4), 64 - 8 {The body's nonspecific resistance factors in a localized experimental infection caused by Bacteroides}; Tyshko AG et al.; Under local experimental infection induced by bacteroides of Fragilis group the factors of nonspecific organism resistance take an active part in the inflammation process . Phase changes of the state of monocytic-phagocytic and complement systems were observed . Peripheral blood leukocyte phagocytic activity decreased at the primary stage, then followed the complement activation by the alternative pathway mainly . The increase of phagocytic and metabolic activities of those phagocytes taking part in the inflammation, the complement at this stage is activated due to the classical pathway while being at the stage of clinic manifestation . Levels of antibody titres are also increasing. Curr Microbiol, 1993 Jun, 26(6), 333 - 6 Breakdown of different peptides by Prevotella (Bacteroides) ruminicola and mixed microorganisms from the sheep rumen; Wallace RJ et al.; Several di-, tri-, and oligopeptides were incubated individually in vitro with rumen fluid from two sheep receiving a mixed grass hay/concentrate diet and with washed cells of Prevotella (formerly Bacteroides) ruminicola M384 and P . ruminicola B(1)4 . The rates of breakdown of most peptides were similar in the rumen fluid from the two sheep . Acidic and proline-containing peptides tended to be more slowly degraded than neutral or basic peptides . The dipeptide at the N-terminus of higher peptides was observed as an early product of hydrolysis, confirming that a dipeptidyl aminopeptidase type of activity was present . The relative rates of breakdown of dipeptides by P . ruminicola were different from that of rumen fluid, but the hydrolysis of higher peptides followed a similar pattern, and dipeptides from the N-terminus were detected as early products. Clin Infect Dis, 1993 Jun, 16 Suppl 4, S160 - 7 Ecophysiology and taxonomy of Bacteroides and related taxa; Shah HN et al.; Recent taxonomic changes among Bacteroides and related species has led to a clearer insight into the site specificity of these taxa . Two recently described centers of variation within the genus Bacteroides sensu stricto and Prevotella intermedia are reported . However, considerable taxonomic problems still remain unresolved within this large and complex group of microorganisms . These bacteria are metabolically diverse, and this is reflected in their colonization sites . In the rumen, gastrointestinal tract, or the oral cavity, specific members of this group contribute significantly to the initial attack on both simple and complex carbohydrates, and by doing so, obtain carbon and energy for their survival . Depletion of carbohydrates from the milieu results in a gradual change in microbial activity to proteolysis . In some sites, such as the periodontal pocket, potent proteinases produced by species such as Porphyromonas gingivalis may facilitate degradation of available proteins to their constituent peptides and amino acids . These products are not only likely to affect the growth of these species, but must profoundly affect the nutrient network of this ecosystem. Antimicrob Agents Chemother, 1993 May, 37(5), 997 - 1000 In vivo efficacies of quinolones and clindamycin for treatment of infections with Bacteroides fragilis and/or Escherichia coli in mice: correlation with in vitro susceptibilities; Brook I; Therapy with ofloxacin, ciprofloxacin, and lomefloxacin (alone or in combination with clindamycin) and therapy with sparfloxacin, clinafloxacin, and temafloxacin alone were given to mice with subcutaneous abscesses . The abscesses were caused by two Bacteroides fragilis isolates, one of which was susceptible and one of which was resistant to ofloxacin, ciprofloxacin, and lomefloxacin, alone or in combination with Escherichia coli . The abscesses were examined 5 days after inoculation . Numbers of B . fragilis organisms reached log10 10.2 to 11.8 per abscess, and numbers of E . coli organisms reached log10 10.6 to 11.8 per abscess . All of the quinolones reduced the number of susceptible B . fragilis isolates (log10 3.6 to 6.9) and E . coli isolates (log10 5.7 to 6.8) . However, ciprofloxacin and lomefloxacin failed to reduce the number of resistant B . fragilis organisms in single-organism or mixed infections . The addition of clindamycin to either ofloxacin, ciprofloxacin, or lomefloxacin reduced the numbers of both susceptible and resistant B . fragilis organisms (log10 3.8 to 7.8) . In contrast, sparfloxacin, clinafloxacin, and temafloxacin were effective as single therapy in eradicating B . fragilis resistant to ofloxacin, ciprofloxacin, and lomefloxacin . These in vivo data confirm the in vitro activity of these quinolones and suggest that although ofloxacin, ciprofloxacin, and lomefloxacin are occasionally effective as single agents in eradicating mixed infection by susceptible strains of B . fragilis and E . coli, addition of an agent with activity against anaerobic organisms will ensure their efficacy . Quinolones with good efficacy against B . fragilis may be effective as single-agent therapy of mixed infections. Antimicrob Agents Chemother, 1993 May, 37(5), 1028 - 36 Genetic and biochemical analysis of a novel Ambler class A beta-lactamase responsible for cefoxitin resistance in Bacteroides species; Parker AC et al.; A clinical isolate of Bacteroides vulgatus was resistant to tetracycline, clindamycin, ampicillin, cephaloridine, cefoxitin, and other beta-lactam antibiotics except imipenem . beta-Lactam resistance was mediated by a membrane-associated, clavulanate-sensitive cephalosporinase capable of degrading cephalosporins and penicillins . Cefoxitin also was degraded but at a slow rate . The cefoxitin resistance (Fxr) determinant was cloned from B . vulgatus genomic libraries that were prepared in Escherichia coli and then mated with Bacteroides fragilis for the identification of Fxr strains . Analysis of B . fragilis strains with the cloned Fxr determinant revealed the presence of a new beta-lactamase protein with the physical and enzymatic properties of the beta-lactamase found in the original B . vulgatus isolate . The beta-lactamase gene (cfxA) was subcloned on a 2.2-kb DraI-HindIII fragment, and the nucleotide sequence was determined . These results showed that cfxA encoded a protein of 321 amino acids and 35,375 molecular weight . Mutant strains in which the cfxA structural gene was disrupted by insertional inactivation lost both Fxr and beta-lactamase activity . Comparison of CfxA with other beta-lactamases showed a relationship with the active-site serine beta-lactamases in the Ambler molecular class A, although CfxA had apparently diverged significantly . This was exemplified by the substitution in CfxA at 13 of 25 amino acid residues previously identified as being invariant in class A beta-lactamases . These results suggest that CfxA may represent a new class A homology group which diverged very early. J Appl Bacteriol, 1993 May, 74(5), 542 - 8 Transfer of hybrid plasmids based on the replicon pRRI7 from Escherichia coli to Bacteroides and Prevotella strains; Bechet M et al.; New shuttle vectors based on a Prevotella ruminicola 9.5 kb cryptic plasmid (pRRI7) inserted within the Escherichia coli vector pKC71, carrying the Ccr/Emr Bacteroides marker, were constructed . These constructs (pKBR23-1 and pKBR23-2) were transferred into Bacteriodes distasonis, Bacteroides thetaiotaomicron, Bacteroides uniformis and into P . ruminicola NCFB 2202 either by conjugal mobilization or by electroporation . Another pRRI7 derivative based on pKC72, pKBR23-3, was smaller (13.1 kb) and non-mobilizable . By electroporation, it was transferred to Bact . distasonis and P . ruminicola . Being derived from pRRI7 which is compatible with the shuttle plasmid pRRI207, the host/vector combination involving P . ruminicola NCFB 2202 and pKBR23-3 offers new possibilities for genetic investigations in rumen anaerobic bacteria after further introduction of a second readily selectable marker within pRRI207 or pKBR23-3. J Bacteriol, 1993 May, 175(9), 2682 - 91 Identification of a circular intermediate in the transfer and transposition of Tn4555, a mobilizable transposon from Bacteroides spp; Smith CJ et al.; Transmissible cefoxitin (FX) resistance in Bacteroides vulgatus CLA341 was associated with the 12.5-kb, mobilizable transposon, Tn4555, which encoded the beta-lactamase gene cfxA . Transfer occurred by a conjugation-like mechanism, was stimulated by growth of donor cells with tetracycline (TC), and required the presence of a Bacteroides chromosomal Tcr element . Transconjugants resistant to either FX, TC, or both drugs were obtained, but only Fxr Tcr isolates could act as donors of Fxr in subsequent matings . Transfer of Fxr could be restored in Fxr Tcs strains by the introduction of a conjugal Tcr element from Bacteroides fragilis V479-1 . A covalently closed circular DNA form of Tn4555 was observed in donor cells by Southern hybridization, and the levels of this circular transposon increased significantly in cells grown with TC . Both the cfxA gene and the Tn4555 mobilization region hybridized to the circular DNA, suggesting that this was a structurally intact transposon unit . Circular transposon DNA purified by CsCl-ethidium bromide density gradient centrifugation was used to transform Tcs B . fragilis 638, and Fxr transformants were obtained . Both the circular form and the integrated Tn4555 were observed in transformants, but the circular form was present at less than one copy per chromosomal equivalent . Examination of genomic DNA from Fxr transformants and transconjugants revealed that Tn4555 could insert at a wide variety of chromosomal sites . Multiple transposon insertions were present in many of the transconjugants, indicating that there was no specific barrier to the introduction of a second transposon copy. Bratisl Lek Listy, 1993 May, 94(5), 267 - 71 {Bacterial flora in the appendix in rabbits with artificially induced acute appendicitis}; Hudac A et al.; The authors present the results of bacteriological analysis of scrapings from the appendical mucosa of 24 rabbits with appendicitis induced by obstruction of the appendix lumen and of 5 rabbits with healthy appendices (controls) . In dependence on the duration of inflammation, the recovery of aerobic bacteria was decreasing and that of anaerobic nonsporulating bacteria was increasing . In the group of anaerobic bacteria, gram-negative rods were predominant (number of isolated colonies: 2973 = 79.9%, variation range of occurrence: 10(5)-10(8) per 1 gram of material) with a remarkable prevalence of the genus Bacteroides and particularly of the species Bacteroides fragilis . Compared to the occurrence in appendices with inflammation, the recovery of bacteria in controls was minimal . The work served as model in studying pathogenesis of acute appendicitis in human medicine . (Tab . 3, Ref . 12.) Biochem Biophys Res Commun, 1993 Apr 30, 192(2), 826 - 32 N-acetyl-D-galactosamine inhibits TNF-alpha gene expression induced in mouse peritoneal macrophages by fimbriae of Porphyromonas (Bacteroides) gingivalis, an oral anaerobe; Murakami Y et al.; Adherence to host cells is an essential step in the initiation of most infectious diseases . It is well known that bacterial fimbriae may be involved in the adherence . Porphyromonas (Bacteroides) gingivalis is a pathogenic organism of adult periodontitis which is a chronic inflammatory disease . Using an experimental system for fimbria-induced TNF-alpha gene expression in mouse peritoneal macrophages, we examined the role of sugar moieties in the adhesion of P . gingivalis fimbriae to these cells . The fimbriae strongly induced TNF-alpha gene expression in the macrophages, and marked TNF activity toward fibroblasts was observed in culture supernatants of the fimbria-treated cells . The potent expression of TNF-alpha was inhibited by N-acetyl-D-galactosamine, but not inhibited by D-mannose, alpha-lactose, and alpha-L-rhamnose, D-galactose, and N-acetyl-D-glucosamine. Dtsch Med Wochenschr, 1993 Apr 23, 118(16), 582 - 6 {The thrombolysis of a septic portal vein thrombosis with ultrahigh-dosage streptokinase}; Dahm JB et al.; Eight days after an appendicectomy a 40-year-old man developed a fever of up to 40.5 degrees C . The concentration of the transaminases was elevated (GOT 61 U/l, GPT 115 U/l, gamma-GT 226 U/l) . Operative revision discovered no unusual wound conditions . Ultrasonography revealed splenomegaly (15 x 7 cm) and dilatation of the portal vein (diameter of 19 mm) . The portal vein contained echo-dense constituents indicating thrombosis . Colour Doppler duplex sonography recorded only minimal residual flow around the thrombus . The fever gradually subsided under antibiotic treatment (metronidazole, 500 mg twice daily; mezlocillin, 2 g three times daily; later also gentamicin, 80 mg three times daily) . Blood culture grew Bacteroides fragilis . 14 days after the wound revision ultra-high short-term lysis with streptokinase was instituted (9 mill IU over 6 hours), followed by heparin i.v . 25,000-30,000 i.v . daily for 5 days . 12 hours after the start of thrombolysis treatment the portal vein thrombus had been dissolved, and after 8 days the size of the spleen was normal. J Biol Chem, 1993 Apr 15, 268(11), 7935 - 42 Purification and characterization of a potent 70-kDa thiol lysyl-proteinase (Lys-gingivain) from Porphyromonas gingivalis that cleaves kininogens and fibrinogen; Scott CF et al.; We isolated an enzyme from a major periodontal pathogen, Porphyromonas gingivalis (also called Bacteroides gingivalis), that is capable of initially increasing the coagulant activity of high molecular weight kininogen (HK), releasing bradykinin from HK and low molecular weight kininogen (LK), and destroying the light chain (coagulant portion) of HK . This enzyme, a membrane-bound thiol proteinase that preferentially cleaves the P1-Lys position of tripeptide substrates, is also able to rapidly render fibrinogen nonclottable . We will refer to this enzyme as lys-gingivain because of its origin from P . gingivalis, its classification as a thiol proteinase, and its action as a lysyl-amidase . The activity of lys-gingivain is enhanced by beta-mercaptoethanol, and the enzyme has a molecular mass of 68-70 kDa, a pH optimum of 7.4, and is not inactivated by plasma protease inhibitors . The second-order rate constant for the destruction of the coagulant activity of the HK light chain (surface-binding domain) at 23 degrees C is 2.3 x 10(7) M-1 s-1, and, for cleavages that render fibrinogen unclottable, is 2.05 x 10(6) M-1 s-1 . These data suggest that lys-gingivain is a very potent proteinase that would be fully functional in anaerobic periodontal crevices and might participate in the pathogenesis of periodontitis . Lys-gingivain appears to be the most potent kininogenase and fibrase to be described to date. Clin Infect Dis, 1993 Apr, 16(4), 561 - 6 Antimicrobial susceptibility patterns and resistance transferability among Bacteroides fragilis group isolates from patients with appendicitis in Bali, Indonesia; Suata K et al.; Patterns of antimicrobial susceptibility were determined for 155 clinical isolates of the Bacteroides fragilis group from patients with acute appendicitis in Bali, Indonesia . The transfer of drug resistance was also studied, and plasmid analyses were undertaken . Metronidazole and chloramphenicol were the most active drugs against these isolates (resistance rate, < or = 0.6%) . Among the beta-lactam drugs, cefoxitin was the most active (resistance rate, 2%) . Rates of resistance to tetracycline were high (16%) . Resistance to clindamycin (rate, 10%) increased during the 2-year study period . Except in the case of beta-lactam agents, overall susceptibility patterns were comparable to those reported from other countries . Tetracycline resistance was more frequently transferred after tetracycline induction than without such induction (P < .05, chi 2 test) . Resistance to tetracycline and clindamycin was co-transferred by five of 12 donor strains . In one of these five strains, transferability was constitutive, with a high transfer frequency (10(-5) per input donor) . Plasmid analysis indicated that the transfer of resistance to tetracycline and clindamycin among the strains studied was not plasmid mediated. J Appl Bacteriol, 1993 Apr, 74(4), 490 - 6 A simple, rapid and sensitive presence/absence detection test for bacteriophage in drinking water; Armon R et al.; A rapid, simple and sensitive direct bacteriophage presence detection method for 500 ml drinking water samples has been developed . The method includes a glass device consisting of a jar containing the water sample and an immersible probe filled with solidified soft agar containing bacterial host cells . Host bacteria in logarithmic phase were added to the experimental volume and the probe was submerged . The entire device was incubated in a water bath at 36 degrees C . Plaques of somatic bacteriophage infecting Escherichia coli strain CN13, could be detected within 3 h . Male-specific bacteriophages infecting E . coli F+ amp were detected within 6 h . Bacteriophage infecting the anaerobe Bacteroides fragilis subsp . fragilis HSP40 were detected after 8 h . Application of this device and the associated technique, enabled a one-step detection of 1 pfu of E . coli or Bact . fragilis specific bacteriophage in 500 ml drinking water samples. Am Rev Respir Dis, 1993 Apr, 147(4), 962 - 6 Intrapleural streptokinase in experimental empyema; Strange C et al.; Intrapleural streptokinase has been used in multiloculated empyemas to enhance pleural space drainage, presumably by causing fibrinolysis of the interlocular septae . We evaluated the efficacy and safety of daily administration of 10,000 U intrapleural streptokinase or equal volumes of saline to enhance resolution of experimental empyema in the rabbit pleural space . Seventy-two hours after intrapleural turpentine, 10(8) colony-forming units each of Escherichia coli, Peptostreptococcus anaerobius, and Bacteroides fragilis were injected into the sterile pleural effusion of all animals . Immediately after bacterial inoculation, and daily for 3 days, animals received 10,000 U streptokinase or saline intrapleurally . Animals that achieved a pleural fluid pH < 7.30 and either glucose < 50 mg/dl or LDH > 500 IU/L were included for data analysis . At Day 4 after bacterial inoculation, the streptokinase-treated empyemic rabbits had more pleural fluid (18.8 +/- 5.1 ml) (mean +/- SEM) than did saline-treated control animals (4.8 +/- 1.7 ml) (p = 0.015), fewer interpleural adhesions (8.2 +/- 2.7) than did saline-treated control animals (25.1 +/- 3.6) (p = 0.002), and comparable amounts of visceral and parietal pleural plaque than did saline-treated control animals (p = NS) . No evidence of systemic fibrinolysis was observed at 1 h after intrapleural streptokinase administration . We conclude that intrapleural streptokinase decreases interpleural adhesion numbers but fails to reduce the amount of pleural plaque observed in experimental empyema in rabbits . The increases in pleural fluid volume observed after streptokinase administration may be due to mechanisms other than fibrinolytic activity. J Clin Microbiol, 1993 Apr, 31(4), 941 - 6 Identification of Bacteroides forsythus in subgingival plaque from patients with advanced periodontitis; Gersdorf H et al.; Bacteroides forsythus has been associated with destructive adult periodontitis . Up to now, detailed analysis by classical means was hampered by the fastidious nature of the organism . There is hope that the application of molecular detection methods such as indirect immunofluorescence or in situ hybridization (ISH) will allow for more rapid and accurate identification . Here we describe a B . forsythus-specific probe (BFV530), complementary to 16S rRNA, which correctly identified all B . forsythus isolates as confirmed by biochemical, protein, or fatty acid analysis . To assess whether this probe might be suitable for direct identification of B . forsythus in clinical specimens, a total of 92 subgingival plaque samples were analyzed . Fifty-five specimens were tested in parallel by culture, light microscopy, and filter hybridization . Unfortunately, the overall agreement between results of filter hybridization and conventional methods was 70.9% only . We therefore examined 37 new specimens by ISH and indirect immunofluorescence by using fluorescently labeled probe BFV530 or B . forsythus-specific monoclonal antibody 116BF1.2 (kindly provided by R . Gmur, Zurich, Switzerland), respectively . Agreement between these methods was 100%, indicating that ISH with probe BFV530 might be used to accurately identify B . forsythus directly in subgingival plaque samples. FEMS Microbiol Lett, 1993 Mar 15, 108(1), 75 - 9 Chemical structure of the 2-keto-3-deoxyoctonate region of lipopolysaccharide isolated from Porphyromonas (Bacteroides) gingivalis; Kumada H et al.; Structural analysis of the 2-keto-3-deoxyoctonate region of lipopolysaccharide (LPS) isolated from Porphyromonas (Bacteroides) gingivalis was carried out . The substitution of the polysaccharide portion on the KDO was determined by gas chromatography/mass spectrometry of the product obtained by sequential derivatization of the LPS, including dephosphorylation, permethylation, carboxyl reduction, partial hydrolysis, carbonyl reduction, complete hydrolysis and O-acetylation . It was revealed that the KDO carries the polysaccharide on its position C5 and is phosphorylated on either position C7 or C8, although its exact position is not determined . The structure of the KDO region of P . gingivalis LPS in Gram-negative bacterial LPS had not hitherto been elucidated. FEMS Immunol Med Microbiol, 1993 Mar, 6(2-3), 103 - 8 Occurrence of plasmids in black-pigmented gram-negative anaerobes; Hohne C et al.; Black-pigmented Gram-negative anaerobes are causative agents of pyogenic infections and are closely linked to various forms of periodontal diseases . Whereas many studies have shown a high incidence of plasmids in intestinal Bacteroides spp., there have been only a few reports of plasmid analyses in pigmented Gram-negative anaerobes . According to previous reports and confirmed in this study, plasmids can be present in Porphyromonas asaccharolytica, Prevotella intermedia, Pr . melaninogenica, and B . levii but have not been detected in P . gingivalis or other black-pigmented species . There were no correlations between plasmids and phenotypes such as resistance to antibiotics or bacteriocinogenicity . The highest carriage rate was found in isolates from cases of chronic otitis media, but the relationship between this site of infection and a high incidence of plasmids could be incidental . The size of plasmids ranged from 1.5 to 29 MDa . Plasmids with molecular weight > 10 MDa were described for the first time in these organisms . Repeated plasmid analyses showed that the plasmid patterns were generally stable. ASDC J Dent Child, 1993 Mar-Apr, 60(2), 99 - 103 The relationship between alveolar bone loss and proximal caries in children: prevalence and microbiology; Bimstein E et al.; The present study describes the prevalence of alveolar bone loss (ABL) in children in relation to caries, contact and space loss . In addition, the microbial composition of the subgingival plaque of 20 sites, from 5 children, is presented . Bite-wing radiographs from 500 children were examined . ABL was evident in: 99 sites from 60 children; > 1 site in 27 children; the maxilla only in 34 children; the mandible only in 17 children; both arches in 9 children; 37 sites with no caries; 4.9 percent of all sites with proximal caries; 15.8 percent of all sites with contact loss; and 20.5 percent of all sites with mesial drift . Anaerobic bacteria were cultured from all 20 sites . No significant differences in the percentages of colony forming units of Actinobacillus actinomycetemcomitans and black pigmented Bacteroides were found among sites with/without bone loss, with/without caries or probing depths smaller/equal or larger than 2.5 mm. J Antimicrob Chemother, 1993 Mar, 31(3), 393 - 401 In-vitro susceptibility and in-vivo efficacy of antimicrobials in the treatment of intraabdominal sepsis in mice; Brook I et al.; Cefoxitin, cefotetan, cefmetazole, ceftizoxime, imipenem plus cilastatin, ampicillin plus sulbactam and clindamycin alone or combined with gentamicin, ciprofloxacin, ofloxacin or aztreonam were compared in the therapy of intraabdominal infection in mice caused by Escherichia coli in combination with either Bacteroides fragilis or Bacteroides thetaiotaomicron . Mortality in the control group was 45%, and no animal receiving either imipenem, gentamicin, ciprofloxacin, ofloxacin or aztreonam died . Mortality in mice receiving cefoxitin, cefotetan, cefmetazole, or ceftizoxime was below 7% (P < 0.05%) and mortality following treatment with ampicillin-sulbactam was 23-27% (P > 0.05) . The abscesses were examined ten days after inoculation . No abscesses were observed in mice treated with clindamycin or imipenem . Therapy with gentamicin, ciprofloxacin, ofloxacin, aztreonam or ceftizoxime alone did not prevent abscess formation by both Bacteroides sp . A significant reduction in abscess formation and number of E . coli and B . fragilis was observed with combination therapy of clindamycin with either ciprofloxacin, ofloxacin, aztreonam, or gentamicin and single agent therapy with either imipenem, cefoxitin, cefotetan, cefmetazole and ampicillin-sulbactam alone . However, cefotetan and cefmetazole did not reduce abscess formation or the number of B . thetaiotaomicron . These in-vivo data confirm the in-vitro activity of these antimicrobials. Mol Microbiol, 1993 Mar, 7(5), 765 - 76 Cloning and identification of a two-component signal-transducing regulatory system from Bacteroides fragilis; Rasmussen BA et al.; A DNA fragment was cloned from Bacteroides fragilis that bestowed low-level tetracycline resistance to Escherichia coli strains harbouring the cloned fragment on a multicopy plasmid . The tetracycline resistance determinant was localized to a 4.3kb Bg/II-PstI subfragment of the original clone . DNA sequence analysis of this fragment revealed that it contained an operon encoding two proteins: one of 519 amino acids, RprX, and a second of 236 amino acids, RprY . Protein sequence analysis revealed that the two proteins shared sequence identity with a family of multicomponent signal-transducing regulatory proteins identified from many diverse bacterial genera . RprX shared identity with the first component of the regulatory system, the histidine protein kinase receptor (for example EnvZ, PhoR, CheA, and VirA) . RprY shared identity with the second member of the regulatory protein pair, the regulatory response protein (for example OmpR, PhoB, CheY, and VirG) . Expression of these proteins from a multicopy plasmid vector in E . coli resulted in a decrease in the level of the outer membrane porin protein OmpF and an increase in the level of the outer membrane porin protein OmpC . The decrease in OmpF levels correlates with, and may be the cause of, the increased tetracycline resistance . Regulation of the levels of OmpF and OmpC is normally controlled by a multicomponent signal-transducing regulatory pair of proteins, EnvZ and OmpR . The effect RprX and RprY have on OmpF expression is mediated at the level of transcription . Thus, RprX and RprY may be interfering with the normal regulation of OmpF by OmpR and EnvZ. Chemotherapy, 1993 Mar-Apr, 39(2), 124 - 7 In vitro activity of a new antibacterial drug, trospectomycin sulphate (U-63,366F), against Bacteroides strains isolated from the vagina; Testore GP et al.; The antibacterial activity of trospectomycin, clindamycin, metronidazole, imipenem, cefoxitin, and piperacillin was tested against 72 Bacteroides spp . strains isolated from the vagina of women with vaginitis by determining the minimal inhibitory concentration using the agar dilution method . Trospectomycin shows a good activity which is comparable to that of imipenem and metronidazole . Its expanded spectrum of activity makes trospectomycin suitable for the use in single-drug therapy of pelvic infections in women. FEMS Immunol Med Microbiol, 1993 Mar, 6(2-3), 83 - 8 Classification and typing methods of black-pigmented gram-negative anaerobes; van Steenbergen TJ et al.; Until recently, black-pigmented Gram-negative anaerobes were classified as 'black-pigmented Bacteroides' . At present, 11 distinct species are recognized in this group . Because of major differences with Bacteroides fragilis, the type species of the genus Bacteroides, new genera have been proposed: Porphyromonas for three asaccharolytic species, and Prevotella for the saccharolytic species . Typing methods have been developed for some species of black-pigmented Gram-negative anaerobes . These include biotyping and serotyping, but relatively few types can be distinguished with these methods . Recently, DNA restriction endonuclease analysis has been used for typing of P . gingivalis, Pr . intermedia and P . endodontalis strains . Great heterogeneity was observed within all three species . This typing method can be useful for epidemiological studies. J Nihon Univ Sch Dent, 1993 Mar, 35(1), 22 - 7 Cytotoxicity versus antibacterial activity of some antiseptics in vitro; Alacam T et al.; Through the development of new techniques for bacterial growth and isolation, obligate anaerobes have been shown to be more prevalent than previously thought in the pathogenesis of periapical and pulpal diseases . A follow-up study was conducted to examine the germicidal effect of 0.05% NaOCl, 10 mg/ml metronidazole and supernatant of Ca (OH)2 (0.025 ml) on four anaerobic microorganisms commonly found in root canals, and to compare the toxicity of these substances on cell cultures . In vitro testing revealed that 0.05% NaOCl and Ca (OH)2 were both equally effective on these anaerobes . Also, metronidazole was found to be germicidally effective against Bacteroides melaninogenicus, Bacteroides oralis and Peptostreptococcus anaerobius, but ineffective against Veillonella alcalescens . Furthermore, it was found that NaOCl and Ca (OH)2 had a very destructive effect on cell cultures compared with their antimicrobial effect, whereas metronidazole was less toxic among the agents tested. Infect Immun, 1993 Mar, 61(3), 1040 - 7 Generation and purification of recombinant fimbrillin from Porphyromonas (Bacteroides) gingivalis 381; Washington OR et al.; Fimbrillin is the major subunit protein of fimbriae from the human periodontal pathogen Porphyromonas (Bacteroides) gingivalis . We describe here the generation and initial characterization of recombinant fimbrillin (r-fimbrillin) isolated from P . gingivalis 381 . A fragment of DNA encoding the gene for fimbrillin was generated by polymerase chain reaction and cloned into the expression vector pET11b . Plasmids containing the recombinant gene were transfected into Escherichia coli . Clones were selected on plates for ampicillin resistance and individually screened by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein production after activation with IPTG (isopropyl-beta-D- thiogalactopyranoside) . One clone, OW0.2, produced significant amounts of a 42-kDa protein after induction with IPTG . This clone contained the pET11b plasmid with a 1-kb insert that had sequence homology to the gene encoding fimbrillin . The majority of recombinant protein from clone OW0.2 was found in the cytoplasm within inclusion bodies . Protein aggregates were solubilized in 8 M urea, and SDS-PAGE analysis showed two major protein bands, one at 42 kDa and the other at 17 kDa . These two proteins coeluted from a DEAE-Sepharose column at 0.15 M NaCl and were reactive to rabbit antiserum to fimbrillin in a Western blot (immunoblot) . A preparation giving a single protein band at 42 kDa in SDS-PAGE was obtained by size fractionation by using continuous-elution electrophoresis . Lymph node cells from animals immunized with either fimbrillin from P . gingivalis or r-fimbrillin showed antigen-specific proliferation to both P . gingivalis fimbrillin and r-fimbrillin in an in vitro recall assay . Therefore, it appears that r-fimbrillin is chemically, antigenically, and serologically identical to fimbrillin isolated from P . gingivalis 381. FEMS Immunol Med Microbiol, 1993 Mar, 6(2-3), 109 - 14 Fluorescence in situ hybridization for direct visualization of gram-negative anaerobes in subgingival plaque samples; Gersdorf H et al.; Fluorescent oligonucleotide probes complementary to variable regions of Porphyromonas gingivalis and Bacteroides forsythus 16S ribosomal RNA were used to identify these organisms in smears of formaldehyde-fixed subgingival plaque samples from patients suffering from periodontitis . Fluorescence in situ hybridization represents a useful method for assessing the microbial ecology of the periodontal flora. J Antimicrob Chemother, 1993 Feb, 31(2), 303 - 11 Comparative chemotherapeutic activity of temafloxacin, cefoxitin, clindamycin, imipenem and ampicillin/sulbactam against Bacteroides fragilis in a mouse subcutaneous abscess model; Alder J et al.; The new fluorinated 4-quinolone temafloxacin was compared with cefoxitin, clindamycin, imipenem (with or without cilastatin) and ampicillin/sulbactam in a mouse subcutaneous abscess model of Bacteroides fragilis infection . Based upon in-vitro susceptibility data, temafloxacin may represent an effective oral and parenteral alternative to standard oral and parenteral anti-anaerobic agents currently in use . Temafloxacin therapy with dosage regimens of < 200 mg/kg/day typically yielded 2-3 x log10 reductions in cfu/abscess, similar to ampicillin/sulbactam, while cefoxitin and clindamycin were generally unable to produce similar reductions at doses up to 400 mg/kg/day . Imipenem (with or without cilastatin) was unable to produce a 1 x log10 reduction at doses of 400 mg/kg/day . This study suggests that temafloxacin has potential for the treatment of anaerobic or mixed aerobic-anaerobic infections in man. Pharm Res, 1993 Feb, 10(2), 258 - 63 In vitro evaluation of calcium pectinate: a potential colon-specific drug delivery carrier; Rubinstein A et al.; Calcium pectinate (CaP)--the insoluble salt of pectin--can potentially be used as a colon-specific drug delivery system . The use of CaP as a carrier was based on the assumption that, like pectin, it can be decomposed by specific pectinolytic enzymes in the colon but that it retains its integrity in the physiological environment of the small bowel . The biodegradation of the carrier was characterized by monitoring the percent cumulative release of the insoluble drug indomethacin, incorporated into pectin or CaP matrices . Compressed tablets of pectin and indomethacin were analyzed for degradation in the presence of Pectinex 3XL, a typical pectinolytic enzyme mixture, and in the presence of the human colonic bacterium Bacteroides ovatus . The degradation of CaP-indomethacin tablets was assessed in the presence of Pectinex 3XL and in rat cecal contents . The release of indomethacin was significantly increased (end-time percentage cumulative release vs control) in the presence of Pectinex 3XL (89 +/- 20 vs 16 +/- 2 for CaP tablets), Bacteroides ovatus (12 and 22 vs 5.2 for pectin tablets), and rat cecal contents (61 +/- 16 vs 4.9 +/- 1.1 for CaP tablets) . The weight loss of tablet mass was significantly higher (end-time dry weight vs control) in the presence of Pectinex 3XL (0 vs 75 +/- 6% of initial weight for CaP tablets) . These findings indicate the potential of CaP, compressed into tablets with insoluble drug, to serve as a specific drug delivery system to the colon. Am J Obstet Gynecol, 1993 Feb, 168(2), 714 - 8 Endotoxin-induced fetal growth retardation in the pregnant guinea pig; Beckmann I et al.; OBJECTIVES: Our purpose was to test the hypothesis that bacterial endotoxin may reduce fetal growth and to assess some of the pathophysiologic mechanisms of such an effect . STUDY DESIGN: Two randomly selected groups of nine guinea pigs at 30 days' gestation were treated with a solution of endotoxin isolated from Bacteroides fragilis or with solvent alone . Antibody titers, glucose, triglycerides, and 6-keto-prostaglandin F1 alpha were determined in maternal or fetal blood samples . Fetal weight was determined at 61 days' gestation . RESULTS: Endotoxin-treated guinea pigs showed positive antiendotoxin antibody titers, reduced weight gain, and significantly higher serum levels of triglycerides and 6-keto-prostaglandin F1 alpha, but not of glucose, than did sham-treated controls . Fetuses of endotoxin-treated animals had significantly lower birth weights and serum glucose concentrations and significantly higher triglyceride levels than did control fetuses . CONCLUSIONS: Bacteroides fragilis endotoxin causes fetal growth retardation in the pregnant guinea pig, which may be due to alterations in carbohydrate and fat metabolism mediated by cytokine action. Oral Microbiol Immunol, 1993 Feb, 8(1), 57 - 61 The effect of incubation temperature on the specificity of the BANA (N-benzoyl-DL-arginine-naphthylamide) test; Feitosa AC et al.; The hydrolysis of BANA by subgingival plaque samples is associated with the presence of either Treponema denticola, Porphyromonas gingivalis, and/or Bacteroides forsythus . A protocol in which pure cultures were incubated for 15 min at 55 degrees C detected about 5 x 10(5) CFU of P . gingivalis and 1 x 10(6) CFU of T . denticola . Clinical studies indicated that the BANA test in this configuration will detect about 10(4) organisms in vivo as compared with the 10(5) to 10(6) organisms found with in vitro grown cells . The BANA test can be made less sensitive by decreasing the time and/or temperature of incubation, which could improve the specificity of the test . In the present study we determined the incubation parameters that would give optimal specificity when the plaque samples were removed from sites of gingival health . Twenty-six approximal plaque samples were taken from each of 90 clinically healthy subjects and incubated with the BANA substrate on PerioScan cards (Oral-B Laboratories) for 5 and 15 min at 35 degrees, 45 degrees, and 55 degrees C . Subjects were randomly assigned to the various temperatures . Wooden toothpicks were inserted interproximally in all sites anterior to distal of the first molars and then each side of the toothpick was wiped onto the PerioScan card . The specificity of the BANA test relative to clinical health was 96% when the cards were incubated for 5 min at 35 degrees C, but decreased to 50-70% when the cards were incubated for 15 min at 35 degrees C or for 5 and 15 min at 45 degrees C and 55 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS) Arch Microbiol, 1993, 159(5), 465 - 71 Pentose utilization and transport by the ruminal bacterium Prevotella ruminicola; Strobel HJ; Plant cell wall polysaccharides are primarily composed of hexose or hexose derivatives, but a significant fraction is hemicellulose which contains pentose sugars . Prevotella ruminicola B14, a predominant ruminal bacterium, simultaneously metabolized pentoses and glucose or maltose, but the organism preferentially fermented pentoses over cellobiose and preferred xylose to sucrose . Xylose and arabinose transport at either low (2 microM) or high (1 mM) substrate concentrations were observed only in the presence of sodium and if oxygen was excluded during the harvest and assay procedures . An artificial electrical potential (delta psi) or chemical gradient of sodium (delta pNa) drove transport in anaerobically prepared membrane vesicles . Because (i) transport was electrogenic, (ii) a delta pNa drove uptake, and (iii) the number of sodium binding sites was approximately 1, it appeared that P . ruminicola possessed pentose/sodium support mechanisms for the transport of arabinose and xylose at low substrate concentrations . Pentose uptake exhibited a low affinity for xylose or arabinose (> 300 microM), and transport of xylose exhibited bi-phasic kinetics which suggested that a second sodium-dependent xylose transport system was present . Little study has been made on solute transport by Prevotella (Bacteroides) species and this work represents the first use of isolated membrane vesicles from these organisms. J Antimicrob Chemother, 1993 Jan, 31(1), 57 - 64 Impact of different statistical methodologies on the evaluation of the in-vitro MICs for Bacteroides fragilis of selected cephalosporins and cephamycins; White RL et al.; The purpose of this study was to assess the effect of different MIC statistics on the in-vitro evaluation of cefoxitin, cefotetan, ceftizoxime, cefotaxime, desacetylcefotaxime, and cefotaxime:desacetylcefotaxime (1:1 ratio) against clinical isolates of Bacteroides fragilis from the Medical University of South Carolina . MICs were determined by the agar dilution method following NCCLS guidelines . Statistical analyses included arithmetic and geometric means, median, mode, MIC50, MIC90, and range . Differences between antimicrobial agents were determined using parametric and nonparametric methods . Consistent with previous in-vitro studies on anaerobes with these agents, a wide range in the MICs was observed . The arithmetic mean MIC was lowest for cefotetan, but the geometric mean MIC was lowest for ceftizoxime . Using the MIC90, cefotetan was at least a two-fold dilution more active than the other agents . After natural logarithmic transformation of the MIC data, analysis of variance with the Scheffe post-hoc test demonstrated that the MICs of ceftizoxime were significantly lower than those of cefoxitin (P < 0.001), cefotetan (P < 0.05), cefotaxime (P < 0.05), and desacetylcefotaxime (P < 0.001) . Median and mode MICs were lowest for ceftizoxime and cefotaxime:desacetylcefotaxime . Using published breakpoints, cumulative percent susceptibility was similar for all agents studied . In this analysis of the antimicrobial susceptibility of B . fragilis in our institution, the in-vitro activity of the cephalosporins and cephamycins tested appeared to be very similar when all statistical data were evaluated . Since apparent in-vitro activity may be influenced by the statistic evaluated, we suggest that all MIC data be reported to allow for a more complete analysis of microbiological potency. Arch Surg, 1993 Jan, 128(1), 73 - 7; discussion 77-8 Anti-tumor necrosis factor antibody reduces mortality in the presence of antibiotic-induced tumor necrosis factor release; Sawyer RG et al.; The systemic tumor necrosis factor (TNF) response has been extensively studied during infection . In addition, antibiotics that cause cell-wall lysis have been associated with endotoxinemia and, therefore, could trigger TNF release . We studied the effects of pretreatment with cefoxitin and/or anti-TNF antibody on mortality and early (90 minutes) and delayed (6 hours) serum TNF levels in a murine model of mixed Escherichia coli/Bacteroides fragilis peritonitis . At low and intermediate inocula levels, cefoxitin, but not anti-TNF antibody, prevented death, and low serum TNF levels were noted in all groups . At the highest inoculum level, mortality was uniform in control, cefoxitin, and anti-TNF antibody groups, and a significant elevation in serum TNF levels was seen only at the 6-hour point in animals receiving cefoxitin . The addition of anti-TNF antibody to cefoxitin at this inoculum level abrogated the 6-hour rise in serum TNF levels and reduced mortality to 40% . These results emphasize that the cytokine response in disease is dependent on both the nature of the insult and other forms of therapeutic interventions. J Med Microbiol, 1993 Jan, 38(1), 13 - 8 In-vitro activity of peritoneal cells from rats after intra-abdominal infection with Bacteroides fragilis and Escherichia coli; Verweij WR et al.; Peritoneal cells from rats infected intraperitoneally with Escherichia coli and Bacteroides fragilis, alone or in combination were examined in vitro . Cells were harvested 6 h after implantation of fibrin clots infected with E . coli or B . fragilis, separately or containing both species, and assayed for their bactericidal capacities, chemiluminescence and production of cidal metabolites . Peritoneal cell populations from rats with implants of any of the infected clots showed similar distribution of different subpopulations . Bactericidal activity of peritoneal cells did not differ with the bacterial species used . Chemiluminescence values of peritoneal cells from rats with mono-infected B . fragilis or mixed-infected implanted clots, after stimulation with either particles or chemical stimuli, were significantly higher than those of rats with mono-infected E . coli or sterile clots . The same tendency was seen with regard to the production of cidal metabolites such as hydrogen peroxide and superoxide anions although no significant differences were found. Microbios, 1993, 75(302), 45 - 56 Polar lipids of strains of Prevotella, Bacteroides and Capnocytophaga analysed by fast atom bombardment mass spectrometry; Drucker DB et al.; The polar lipid composition of representative strains of Bacteroides fragilis, Prevotella intermedia, P . melaninogenica and Capnocytophaga ochracea was determined . Samples were analysed by FAB-MS . Forty major peaks had m/z values expected for known carboxylate anions, ranging from m/z 211 (tridecenoate) to m/z 381 (pentacontanoate) . A further fifty-five major peaks were studied between m/z 561 and m/z 722 . Forty-five anionic phospholipids of several series were identified . The Pearson coefficient of linear correlation revealed the similarity of the P . intermedia spectra from repeat experiments (r = 0.98), as opposed to inter-species comparisons (0.55, 0.22, 0.20) . Thus, FAB-MS rapidly yields data on molecular species within phospholipid families not readily obtained by other means . The data obtained may have chemotaxonomic potential. Pneumonol Alergol Pol, 1993, 61(3-4), 144 - 7 {Aerobic and anaerobic bacterial flora as a cause of lower respiratory tract infection}; Rylski M et al.; Bronchial aspirates collected from a group of 100 patients with respiratory infections undergoing broncho-fiberscopic examination have been tested bacteriologically . Twenty five patients was suffered from bronchopneumonia, 35 patients have had acute bronchitis, and 40 patients chronic bronchitis . Aerobic bacterial flora has been detected in 15% of patients, anaerobic flora in 13%, an mixed bacterial flora in 20%, totally in 48% of cases . Aerobic bacteria predominated in pneumonia . Bacteroides melaningogenicus prevailed in anaerobic flora . The tests of bacterial sensitivity to antibiotics have shown high sensitivity to cefotaxime, cefamandole, metronidazole, and rifampicin. Scand J Infect Dis, 1993, 25(3), 347 - 51 Significant decrease of gram-negative anaerobic bacteremia in a major hospital from 1967-73 to 1981-89: an effect of the introduction of metronidazole? Siboni A, Graversen K, Olsen H. Declining rates of anaerobic bacteremia are reported from medical centres all over the world . At Odense University Hospital the frequency of Gram-negative anaerobic bacteremia decreased from 1.62% in 1967-73 to 0.83% in 1981-89 (p < 0.001) . Metronidazole prophylaxis prior to bowel surgery seems to be the most important explanation, as the association of Bacteroides bacteremia with surgery decreased from 80% to 48% (p < 0.01) and no cases of Bacteroides bacteremia occurred during metronidazole treatment without the presence of abscess or gangrene . A contributory factor may be improved methods for abscess localization and drainage . Other drugs having an effect on anaerobes seem of minor importance . A new category of patients seems to be those who have undergone aorto-femoral bypass operation for aneurysm of the aorta . They contract anaerobic Gram-negative bacteremia from infected hematomas or intestinal gangrene. Biol Neonate, 1993, 63(3), 191 - 200 Postnatal changes in selected bacterial groups of the pig colonic microflora; Swords WE et al.; The importance of the colonic microflora in health and nutrition is well known, but how they colonize and become established in the colon is not well understood . We therefore characterized the quantitative and qualitative changes of the colonic microflora during the first 120 days of postnatal development . Unlike previous studies, changes were defined for individual pigs using in situ samples collected anaerobically and aseptically from the distal colon . Although the colons were sterile at birth, they were rapidly colonized, and within 12 h bacterial densities had stabilized at 10(-9)-10(10) bacteria/g colonic content . Facultative anaerobes, notably coliforms, initially dominated the microflora, but were supplanted within 48 h after birth by obligate anaerobes, which constituted greater than 90% of the microflora thereafter . Bacteroides spp., the predominant anaerobes in the adult colon, did not markedly increase in abundance until after weaning and were still increasing by postnatal day 120 . Shifts in the relative abundances of different bacterial populations throughout the first 120 days after birth confirm previous reports that the establishment of the adult colonic microflora is a gradual, sequential process, and highlight the need to focus research on anaerobic groups. Rev Inst Med Trop Sao Paulo, 1993 Jan-Feb, 35(1), 107 - 10 Antimicrobial resistance and plasmid detection in strains of the Bacteroides fragilis group; Avila-Campos MJ et al.; Resistant populations of the Bacteroides fragilis group bacteria (two reference ones and two isolated from human and Callithrix penicillata marmoset) were obtained by the gradient plate technique, to clindamycin, penicillin G, metronidazole and mercuric chloride . All the four tested strains were originally susceptible to the four antimicrobial drugs at the breakpoint used in this study . MICs determination for the four cultures gave constant values for each antimicrobial, on the several steps by the gradient plate technique . The intestinal human B . fragilis strains showed three DNA bands, that could be representative of only two plasmids in the closed covalently circular (CCC) form with molecular weights of approximately 25 and 2.5 Md . The results do not permit an association between the presence of plasmid in the human strain with the susceptibility to the studied drugs . The four strains were beta-lactamase negative in the two methods used, and no particular chromosomal genetic resistance marker was demonstrated . The resistance (MIC) observed, after contact with penicillin G and mercuric chloride, were two-fold in the four tested strains. Microbios, 1993, 75(305), 233 - 40 Influence of short-chain fatty acids produced by anaerobic bacteria on procoagulant activity produced by Escherichia coli and Bacteroides fragilis-stimulated leucocytes: possible role in intra-abdominal abscess formation; Miragliotta G et al.; The effect of selected short-chain fatty acids (SCFA) produced by anaerobic bacteria on the production in vitro of procoagulant activity (PCA) by human mononuclear cells stimulated by either Escherichia coli or Bacteroides fragilis which are common pathogens in intra-abdominal infections was investigated . In particular, acetic, propionic, succinic, butyric, and isobutyric acids were evaluated . Acetic, butyric, and isobutyric acids were able to inhibit significantly the production of PCA by bacteria-stimulated mononuclear cells . Since the production of PCA leads to the deposition of fibrin which is considered critical to the establishment of intra-abdominal abscesses, the inhibitory effect exerted by SCFA present in the inflammatory environment might play an important modulating role in the development of abscesses complicating intra-abdominal infections. Med Dosw Mikrobiol, 1993, 45(3), 345 - 8 {Biological activity of Bacteroides fragilis}; Leszczynski P et al.; The investigation was performed with 9 strains of B . fragilis isolated from pregnant women in their 38th week of pregnancy, strain IPLE 323 obtained from France, strains BE17 and BE61 obtained from Netherlands and a strain 210 isolated from a case of appendicitis . The strains were identified by indirect immunofluorescence method and by API 32 ATB test . Ability to adhere to epithelium of oral cavity and vaginal mucosa and sheep and human erythrocytes was investigated . Susceptibility to antibiotics was also measured . It was found that strains isolated from vagina easier adhere to epithelial cells of vagina than to cheek epithelium and erythrocytes. Egypt Dent J, 1993 Jan, 39(1), 381 - 6 Antibacterial action of natural honey on anaerobic bacteroides; Elbagoury EF et al.; Two samples of natural Honey were tested for their antibacterial effect on Bacteroides, mainly the pathogenic black pigmented B . melaninogenicus isolated from ten cases of dental infections (dental abscesses and chronic osteomyelitis) . These organisms were subjected to the effect of natural and diluted honey (50%), in broth and solid cultures . The results were compared with those of the same organisms incubated with saturated glucose solution, which showed less inhibition, indicating that the inhibitory effect of honey was not due to its high sugar content nor to its acidic PH, when using Schaedler's broth adjusted to the same PH as control . The local therapeutic value of natural honey was illustrated with an attempt to correlate between the microbial findings and the clinical implications. Nippon Jibiinkoka Gakkai Kaiho, 1992 Dec, 95(12), 1901 - 5 {A case of Bezold's abscess associated with cholesteatoma}; Furukawa K et al.; Since the advent of antibiotics, otogenic complications have decreased considerably . However, incomplete antibiotic therapy has altered the clinical course of middle ear disease so as to be more insidious . This paper reports a case of Bezold's abscess associated with cholesteatoma . A 48-year-old man visited our hospital presenting with a 4-day history of right otorrhea and a tender swelling in the right neck . Physical examination showed a febrile patient (38.8 degrees C) with right facial paresis and trismus . A hyperemic, hard and tender swelling was observed in his right neck from the lateral cervical to the mental region . The tympanic membrane was invisible because of granulation and swelling of the posterior wall of the external auditory canal . Intravenous clindamycin and ceftazidime therapy was started immediately . A CT-scan revealed a diffuse shadow with bony destruction in the right mastoid cortex . Extensive abscess formation was also found in the right sternocleidomastoid muscle, in the anterior neck and in the posterior neck . He was diagnosed as having Bezold's abscess associated with cholesteatoma . Radical mastoidectomy and drainage of the neck abscess was performed on the third day under general anesthesia . The mastoid cavity was found to be filled with pus and cholesteatoma debris . A small area of defective bone was found at the mastoid tip, through which there were communications between the mastoid cavity and the abscesses in the neck . Bony destruction was also found in the horizontal and vertical portion of the facial canal . Bacteroides and three kinds of gram-negative rods were cultured from the mastoid cavity.(ABSTRACT TRUNCATED AT 250 WORDS) FEMS Microbiol Lett, 1992 Dec 1, 78(2-3), 137 - 43 Distribution of xylanase genes and enzymes among strains of Prevotella (Bacteroides) ruminicola from the rumen; Avgustin G et al.; The distribution of two xylanase genes was examined by Southern hybridization among 26 strains of the rumen anaerobic bacterium Prevotella (Bacteroides) ruminicola . Hybridization with a xylanase/endoglucanase gene from the type strain 23 was found in six strains while hybridization with a xylanase gene from strain D31d was found in 14 strains . Sequences related to both genes were present, on different restriction fragments, in six strains, whereas no hybridization to either gene was detected in five other strains capable of hydrolysing xylan, or in seven strains that showed little or no xylanase activity . Zymogram analyses of seven xylanolytic strains of P . ruminicola demonstrated interstrain variation in the apparent molecular masses of the major xylanases and carboxymethylcellulases that could be renatured following SDS polyacrylamide gel electrophoresis. Oral Microbiol Immunol, 1992 Dec, 7(6), 349 - 56 Expression of Porphyromonas gingivalis proteolytic activity in Escherichia coli; Madden TE et al.; Porphyromonas gingivalis (formerly Bacteroides gingivalis) degrades numerous protein substrates including collagen, fibrinogen, fibronectin, gelatin, casein, immunoglobulins and complement components . In order to clone one or more of these protease genes, a genomic library was constructed with Sau3A1 restriction fragments of chromosomal DNA from P . gingivalis ATCC 33277 ligated into the temperature-regulated vector pCQV2, and expressed in Escherichia coli DH5 alpha mcr . The electro-transformants (3 x 10(4)) were screened for general protease activity on Luria broth agar containing ampicillin (50 mg/l) and sodium caseinate (2%) . One casein-hydrolyzing clone was detected and subcultured, and the activity of the cell extracts was characterized . We were able to show that the protease-positive clone, (pTEM1), had broad substrate specificity . Colorimetric assays indicated the hydrolysis of azocoll, azocasein, collagen, elastin-congo red and artificial substrates . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to confirm that collagen, casein, fibrinogen and fibronectin were degraded by the clone. Kansenshogaku Zasshi, 1992 Dec, 66(12), 1660 - 9 Aerobic and anaerobic bacterial interactions in the development of anaerobic bacterial pneumonia; Goto J; The interactions between aerobic and anaerobic bacteria in the development of anaerobic bacterial pneumonia were studied by introducing Bacteroides fragilis and Escherichia coli alone or in combination into guinea pigs by tracheal infusion . The lung lesions induced by B . fragilis were mainly located near the pleura, unlike those induced by E . coli, and were accompanied by pneumonia, lung abscess, and pleuritis . The lung lesions produced by mixed infection with B . fragilis (10(9) cfu) and E . coli (10(7) cfu) were significantly more severe than those induced by either microbe alone, and the redox potentials at the foci of inflammation were markedly reduced (max: -330 mV) . Analysis of lung lesions after treatment with aztreonam and clindamycin and neutrophil phagocytic activity suggested that E . coli was primarily responsible for the lung lesions and that B . fragilis promoted the accompanying inflammation, resulting in increased pathogenicity of the mixed infections. J Antimicrob Chemother, 1992 Dec, 30(6), 811 - 20 Antimicrobial susceptibility of anaerobic bacteria in Australia; Chen SC et al.; The susceptibilities of 900 clinical isolates of anaerobic bacteria to 14 antimicrobial agents were determined by an agar dilution technique . Chloramphenicol, imipenem and metronidazole were found to be active against virtually all of the strains; only a single Bacteroides fragilis isolate was resistant to both imipenem and metronidazole . The addition of clavulanic acid to amoxycillin and ticarcillin potentiated the activities of these agents against all anaerobes including members of the B . fragilis group . Ampicillin/sulbactam and clindamycin were the next most active agents, 91 and 89% of isolates respectively being susceptible . Seventy-three per cent of the bacteria tested were susceptible to cefoxitin and 65% to cefotetan, with the MICs of almost 50% of the isolates clustering between 16 and 32 mg/L . There was also clustering around the breakpoint (64 mg/L) of piperacillin . Azithromycin exhibited poor activity against the B . fragilis group; only 18% of isolates were susceptible to < or = 4 mg/L . However, 92% of non-B . fragilis Bacteroides group strains were susceptible to this agent . We conclude that imipenem, metronidazole, chloramphenicol, ticarcillin/clavulanate, co-amoxiclav and, to a lesser extent, ampicillin/sulbactam are suitable as empirical therapy for infections caused by anaerobic bacteria. Biochem Biophys Res Commun, 1992 Nov 30, 189(1), 524 - 9 Purification and characterization of a sialidase from Bacteroides fragilis SBT3182; Tanaka H et al.; A sialidase from Bacteroides fragilis SBT3182 was purified 2,240-fold to apparent homogeneity by ammonium sulfate precipitation and sequential chromatographies on DEAE-Toyopearl 650M, Hydroxyapatite, MonoS and Superose6 columns . The N-terminal amino acid sequence of this sialidase, Ala-Asp-X-Ile-Phe-Val-Arg-Glu-Thr-Arg-Ile-Pro-, was determined . Substrate specificity of this enzyme using a variety of sialoglycoconjugates showed a 1.5- and 2.2-fold preference for sialyl alpha 2-8 linkages when compared with alpha 2-3 and alpha 2-6 bound sialic acids, respectively . The native sialidase had a molecular weight of 165kDa, as determined by Superose6 gel filtration chromatography and consisted of three subunits each of 55kDa by SDS-polyacrylamide gel electrophoresis . This enzyme had optimal activity at pH6.1 with colominic acid as substrate. J Periodontal Res, 1992 Nov, 27(6), 615 - 22 The mechanisms of Eikenella corrodens aggregation by salivary glycoprotein and the effect of the glycoprotein on oral bacterial aggregation; Ebisu S et al.; The mechanism of aggregation of Eikenella corrodens 1073 with E . corrodens aggregating factor (EcAF) which was purified from submandibular-sublingual (SM-SL) saliva was investigated . Heating (100 degrees C, 10 minutes) or protease treatment of E . corrodens cells abolished the aggregating activity . The aggregation was inhibited by adding N-acetyl-D-galactosamine (GalNAc) and saccharides which contain a galactose residue at the non-reducing end . The aggregating activity was sensitive to EDTA and was restored by Ca2+ but not by Mn2+ or Mg2+ . Neuraminidase treatment of EcAF increased their ability to aggregate . E . corrodens, suggesting that the sialic acids on EcAF interfere with aggregation . These data suggest that the aggregation of E . corrodens 1073 with EcAF is mediated by specific interactions between a bacterial cell surface lectin-like substance and a complementary GalNAc-like receptor . EcAF also aggregated 16 strains of oral bacteria including periodontopathic bacteria such as Porphyromonas (Bacteroides) gingivalis 381 and Actinobacillus actinomycetemcomitans ATCC29522; however, those aggregations were not inhibited by GalNAc . Therefore, EcAF appears to have more than two types of bacterial binding site and plays important roles in accumulation of dental plaque by forming a complex network of plaque bacteria including periodontopathic strains. Clin Infect Dis, 1992 Nov, 15(5), 771 - 3 Anaerobic osteomyelitis in patients with Gaucher's disease; Finkelstein R et al.; Bone involvement in patients with Gaucher's disease is common, and some of its clinical manifestations may resemble acute osteomyelitis . In addition, many studies have emphasized the high risk of secondary infection when surgical procedures are performed at the site of the involved bone . Nevertheless, these infections have never been well documented in the literature . Presentation of a patient with Gaucher's disease and osteomyelitis due to Prevotella (Bacteroides) melaninogenica provided us the opportunity to review 10 other similar case reports documented in the literature since 1966 . This review suggests that acute hematogenic osteomyelitis is an uncommon complication of Gaucher's disease, but it is of interest that in most cases it is due to unusual organisms, particularly anaerobes. Oral Surg Oral Med Oral Pathol, 1992 Nov, 74(5), 648 - 51 Complement activation by lipopolysaccharides purified from gram-negative bacteria isolated from infected root canals; Horiba N et al.; The purpose of the present study was to investigate the complement activation by lipopolysaccharides purified from Porphyromonas (Bacteroides) endodontalis, Veillonella parvula, and Fusobacterium nucleatum isolated from infected root canals . The rate of consumption of the C3T component of the complement increased remarkably when lipopolysaccharides of more than 10 micrograms were added. J Hosp Infect, 1992 Nov, 22 Suppl A, 75 - 87 The management of acute, serous and chronic otitis media: the role of anaerobic bacteria; Brook I et al.; Otitis media (OM) is a common childhood disease and one which can cause significant morbidity . A knowledge of the pathogens responsible for OM enables the most appropriate treatment regimen to be selected and thus minimizes further complications which may require hospital admission and surgery . The microbiology of acute, serous and chronic OM is reviewed, with particular regard to the role of anaerobic bacteria . Anaerobes, mainly Gram-positive cocci, have been recovered from 25% of the ear aspirates of patients with acute otitis media . In a study of serous OM, anaerobic bacteria were recovered in 12% of the culture-positive aspirates . The predominant anaerobes were Gram-positive cocci and pigmented Prevotella . Several studies have reported the recovery of anaerobes from about 50% of patients with chronic OM and those with cholesteatoma . The predominant anaerobes were Gram-positive cocci, pigmented Prevotella, Porphyromonas sp., Bacteroides spp . and Fusobacterium spp . Many of these organisms produce beta-lactamase which might have contributed to the failure of the patients to respond to penicillins . The appropriate antimicrobial therapy for acute, serous and chronic otitis media is discussed. J Infect, 1992 Nov, 25(3), 251 - 7 Encapsulation and pilus formation of Bacteroides spp . in normal flora abscesses and blood; Brook I et al.; The presence of encapsulated and piliated Bacteroides spp . (mostly Bacteroides fragilis and melaninogenicus groups was investigated in isolates from blood, abscesses and normal flora . Of the strains of Bacteroides spp . isolated 45 of 54 (83%) recovered from blood and 31 of 40 (78%) found in abscesses were encapsulated . In contrast, only seven of 71 (10%) similar strains isolated from the faeces or pharynx of healthy persons were encapsulated (P < 0.001) . Pili were observed in three of 54 (6%) of strains isolated from blood, 30 of 40 (75%) of those recovered from abscesses (P < 0.001), and 49 of 71 (69%) of those found in normal flora (P < 0.001) . The predominance of encapsulated forms in all strains of B . fragilis and B . melaninogenicus in blood as well as in abscesses suggests an increased virulence of these compared with non-encapsulated isolates . In contrast, the presence of pili in Bacteroides spp . recovered mostly from abscesses and normal flora suggests that this structure may play a role in the ability of these organisms to adhere to mucous membranes and may interfere with their ability to spread systemically . These findings illustrate the morphological differences that may be observed in Bacteroides spp . from various anatomical sites. Eur J Clin Microbiol Infect Dis, 1992 Nov, 11(11), 1094 - 9 Survey of the susceptibility patterns of Bacteroides fragilis group strains in France from 1977 to 1992; Dubreuil L et al.; Rates of antibiotic resistance within the Bacteroides fragilis group were monitored over a 15-year period in France by examining studies that employed the same methodology to test susceptibility of anaerobic bacteria . Chloramphenicol, metronidazole, beta-lactam/beta-lactamase inhibitor combinations and imipenem remained very active against Bacteroides fragilis . There was little or no change in rates of resistance to these antibiotics . Resistance to clindamycin increased from 1% in 1977 to a peak of 19% in 1987, and since then has remained at 8 to 12% . There was some evidence that resistance to most beta-lactam agents increased during the same period . These results emphasize the need for periodic surveys of resistance patterns of the Bacteroides fragilis group in each country. Eur J Clin Microbiol Infect Dis, 1992 Nov, 11(11), 1069 - 73 In vitro susceptibility of clinical isolates of Bacteroides fragilis and Bacteroides thetaiotaomicron in Japan; Watanabe K et al.; A nationwide survey of the susceptibility of 433 isolates of Bacteroides fragilis and 149 isolates of Bacteroides thetaiotaomicron was conducted from December 1986 through November 1989 in Japan . These strains were collected from 16 university hospitals and one metropolitan hospital . Metronidazole was the most active drug against both species, with no resistant isolates found . The activity of imipenem and sulbactam-cefoperazone was good, with very low resistance rates determined in Bacteroides fragilis (1.4% and 1.6%, respectively) and in Bacteroides thetaiotaomicron (3.4% for both drugs), and was comparable to that of metronidazole . Cefoxitin, cefmetazole, cefotetan, cefbuperazone, latamoxef and ceftizoxime were found to be more active against Bacteroides fragilis, for which resistance rates were 3.2 to 9.5%, than against Bacteroides thetaiotaomicron, for which resistance rates were 18.1 to 21.8% . Rates of piperacillin resistance in the two species were 12.9% and 26.8%, respectively . Clindamycin was very active at a low concentration (MIC50 of 0.39 to 1.56 mg/l), but 24% and 27.5% of Bacteroides fragilis and Bacteroides thetaiotaomicron isolates, respectively, were resistant to this agent. Oral Microbiol Immunol, 1992 Oct, 7(5), 267 - 72 Periodontal pathogens in the shallow pockets of immigrants from developing countries; McNabb H et al.; The aim of this study was to examine the distribution of typical periodontitis-associated microorganisms in refugees arriving from non-industrialized countries, and to relate the presence of these organisms to the periodontal condition of the subjects . Thirty males between 35-44 years of age were surveyed . Dental plaque, calculus, gingivitis, loss of attachment, and probing depths were recorded for all surfaces . A total of 90 microbiological samples were taken with paper points from mesial sites of teeth 16, 36 and 41 . Microbiological test sites were grouped by probing depths and loss of attachment . Only 16.8% of all surfaces had probing depths > 3 mm, although 90.7% of surfaces had loss of attachment > 1 mm . Twenty-one sites with obvious periodontal destruction (PD > 3 mm, LA > 2 mm) showed the greatest recovery of Porphyromonas gingivalis (66.7%) . However, 51 sites with minimal periodontal disease (PD < or = 3 mm, LA < 2 mm) and with no gingival recession also showed a relatively high detection frequency of P . gingivalis (34.1%) . Twenty-four of these samples came from 12 patients with no pockets > 5 mm and with less than 10% of all sites yielding pockets > 3 mm . The detection frequencies of Prevotella intermedia (91.6%), Bacteroides forsythus (25.0%), Wolinella spp . (33.3%) and Actinobacillus actinomycetemcomitans (50.0%) were similar in these sites compared with periodontitis sites . Morphologically distinct isolates, from 19 individuals positive for A . actinomycetemcomitans, were serotyped by indirect immunofluorescence.(ABSTRACT TRUNCATED AT 250 WORDS) J Chemother, 1992 Oct, 4(5), 271 - 5 Hepatic and intestinal effects of flurithromycin and erythromycin in the rat; Benoni G et al.; The effects of flurithromycin (30-100 mg/kg p.o.), a fluorinated macrolide, on rat hepatic enzymes and intestinal microflora have been compared with those of equal doses of erythromycin . This latter drug significantly decreases cytochrome b5, cytochrome P-450 and aminopyrine N-demethylase and moderately influences intestinal microbial flora . Flurithromycin showed almost opposite characteristics, with no hepatic interaction and marked effects on some bacterial species (e.g . Bacteroides) known to facilitate the colonization of pathogenetic bacteria. J Clin Periodontol, 1992 Oct, 19(9 Pt 2), 702 - 7 The effect of topical metronidazole therapy on experimentally-induced periodontitis in the beagle dog; Klinge B et al.; The present study was performed to assess the effect of topical metronidazole therapy on ligature-induced periodontitis in beagle dogs . 6 beagle dogs with experimentally-induced periodontitis on the mandibular 2nd, 3rd and 4th premolars were treated with metronidazole 10% dental paste 2 x daily for 4 weeks in an open placebo-controlled study using a split-mouth design . Recordings of probing pocket depth, bleeding on probing and gingival index were performed before commencement of treatment and repeated weekly during the 4-weeks treatment period . Concurrently, samples for microbiological analysis were collected from 2 of the dogs . The results demonstrated that probing pocket depth, bleeding on probing and gingival index had improved significantly in the metronidazole-treated side compared with the placebo-treated side . Black pigmented Bacteroides spp . and Spirochetes, present in all samples before treatment, were eliminated from the metronidazole-treated side after the 1st week of treatment and throughout the treatment period, whereas they were present in all samples from the placebo-treated side . The result of the present study demonstrates that topical application of metronidazole in a dental paste, improves the clinical features of the experimentally-induced periodontitis and eliminates some of the micro-organisms associated with the disease. Surg Neurol, 1992 Oct, 38(4), 287 - 90 Acute intramedullary spinal cord abscess: case report; Erlich JH et al.; We report the first case of an acute pyogenic intramedullary cervical spinal cord abscess, brain abscesses and meningitis due to an unusual anerobe, Bacteroides disiens . The importance of spinal magnetic resonance imaging for establishing the diagnosis is emphasized. Scand J Gastroenterol, 1992 Oct, 27(10), 845 - 51 Proliferative activity of bile duct epithelium after bacterial infection in dogs; Ohta T et al.; To clarify the relationship between proliferative activity in bile duct epithelia and bacterial infection in the dog, we induced obstructive cholestasis with a bacterial infection in two lobes of the liver . The bile duct branch draining the left lateral lobes of the liver was cannulated in all mongrel dogs . The dogs were divided into three groups and treated as follows: in group 1 the cannula was clamped after the injection of 10(7) Escherichia coli (aerobic bacteria) and 10(7) Bacteroides fragilis (anaerobic bacteria) cells; in group 2 the cannula was clamped after the injection of 10(7) E . coli cells; and in group 3 the cannula was clamped without the injection of any bacteria . Three months and 9 months later dogs from each group were killed, and their livers were examined . In the group 1 dogs papillary hyperplasia and severe dysplasia were noted in association with chronic cholangitis at 3 months and 9 months, respectively, after operation . In the group 2 dogs periductal fibrosis was severe, but epithelial papillary hyperplasia was less pronounced than in the group 1 dogs at each period . In the group 3 dogs no periductal fibrosis or epithelial papillary hyperplasia was seen at either 3 or 9 months postoperatively . These findings suggest that papillary hyperplasia and/or severe dysplasia of the bile duct epithelium may be caused by aerobic and anaerobic bacterial infection of the biliary tract in combination with bile stasis. J Clin Invest, 1992 Oct, 90(4), 1313 - 22 Degradation of endogenous bacterial cell wall polymers by the muralytic enzyme mutanolysin prevents hepatobiliary injury in genetically susceptible rats with experimental intestinal bacterial overgrowth; Lichtman SN et al.; Jejunal self-filling blind loops with subsequent small bowel bacterial overgrowth (SBBO) induce hepatobiliary injury in genetically susceptible Lewis rats . Lesions consist of portal tract inflammation, bile duct proliferation, and destruction . To determine the pathogenesis of SBBO-induced hepatobiliary injury, we treated Lewis rats with SBBO by using several agents with different mechanisms of activity . Buffer treatment, ursodeoxycholic acid, prednisone, methotrexate, and cyclosporin A failed to prevent SBBO-induced injury as demonstrated by increased plasma aspartate aminotransferase (AST) and elevated histology scores . However, hepatic injury was prevented by mutanolysin, a muralytic enzyme whose only known activity is to split the beta 1-4 N-acetylmuramyl-N-acetylglucosamine linkage of peptidoglycan-polysaccharide (PG-PS), a bacterial cell wall polymer with potent inflammatory and immunoregulatory properties . Mutanolysin therapy started on the day blind loops were surgically created and continued for 8 wk significantly diminished AST (101 +/- 37 U/liter) and liver histology scores (2.2 +/- 2.7) compared to buffer-treated rats (228 +/- 146 U/liter, P < 0.05, 8.2 +/- 1.9, P < 0.001 respectively) . Mutanolysin treatment started during the early phase of hepatic injury, 16-21 d after surgery, decreased AST in 7 of 11 rats from 142 +/- 80 to 103 +/- 24 U/liter contrasted to increased AST in 9 of 11 buffer-treated rats from 108 +/- 52 to 247 +/- 142 U/liter, P < 0.05 . Mutanolysin did not change total bacterial numbers within the loop, eliminate Bacteroides sp., have in vitro antibiotic effects, or diminish mucosal PG-PS transport . However, mutanolysin treatment prevented elevation of plasma anti-PG antibodies and tumor necrosis factor-alpha (TNF alpha) levels which occurred in buffer treated rats with SBBO and decreased TNF alpha production in isolated Kupffer cells stimulated in vitro with PG-PS . Based on the preventive and therapeutic activity of this highly specific muralytic enzyme, we conclude that systemic uptake of PG-PS derived from endogenous enteric bacteria contributes to hepatobiliary injury induced by SBBO in susceptible rat strains. J Clin Periodontol, 1992 Oct, 19(9 Pt 1), 667 - 71 Occurrence of periopathogens in smoker and non-smoker patients; Preber H et al.; The aim of the present study was to elucidate the interrelationship between cigarette smoking and the occurrence of periopathogens, i.e., Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Bacteroides intermedius . The study was based on 145 patients with clinically severe periodontitis, 52 men (age range 32-73 years) and 93 women (age range 32-74 years) . 83 patients were smokers (> or = 15 cigarettes/day) and 62 non-smokers . Bacterial samples were collected from one site with a probing depth > or = 6 mm for each individual . There were no statistically significant differences in bacterial counts between smokers and non-smokers (p > 0.05) . The relative frequencies of smokers and non-smokers positive for A . actinomycetemcomitans were 31% and 31%, for B . gingivalis 42% and 44%, and for B . intermedius 65% and 53%, respectively . The differences between smoking groups were not statistically significant (p > 0.05) . The occurrence in different combinations of these bacteria was also determined . There were no statistically significant differences between smoking and combinations of periopathogens (p > 0.05) . The results suggest that smoker and non-smoker patients do not differ with regard to occurrence, relative frequency or different combinations of A . actinomycetemcomitans, B . gingivalis and B . intermedius. Zentralbl Bakteriol, 1992 Oct, 277(3), 320 - 8 Species specific monoclonal antibodies to Bacteroides fragilis lipopolysaccharide protect mice from severe infection; Brake B et al.; Four monoclonal antibodies which reacted in a species specific manner with Bacteroides fragilis were isolated . They recognised at least two different epitopes of B . fragilis lipopolysaccharide . The monoclonal antibodies protected non-immune mice from longlasting bacteraemia and abscess formation induced by the intraperitoneal administration of B . fragilis in combination with an infection-potentiating agent . The monoclonal antibodies were as efficient as an anti-B . fragilis hyperimmune serum . Only antibodies administered intraperitoneally or intramuscularly were protective. J Biol Chem, 1992 Sep 15, 267(26), 18902 - 7 Activation of complement components C3 and C5 by a cysteine proteinase (gingipain-1) from Porphyromonas (Bacteroides) gingivalis; Wingrove JA et al.; Complement components C3 and C5 are susceptible to limited proteolysis by an arginine-specific cysteine proteinase isolated from Porphyromonas gingivalis . This bacterium is an anaerobe commonly associated with severe periodontal disease . Infection by P . gingivalis is accompanied by an acute inflammatory response, complete with extensive neutrophil involvement . This prompted us to investigate a possible direct role for complement in periodontitis evoked by P . gingivalis . Exposure of C3 and C5 to the cysteine proteinase at molar ratios between 1:25 and 1:100 (enzyme to substrate ratios) resulted in a time-dependent, limited degradation of each component . C3 was converted in a stepwise manner to C3a-like and C3b-like fragments with evidence of extensive further degradation of the C3a-like portion of the molecule . We were unable to demonstrate C3a activity in the C3 digestion mixtures . C3 degradation appears to involve primarily the alpha-chain . Proteolysis of C5 also progresses in a stepwise manner producing an initial internal cleavage of the alpha-chain to generate 30- and 86-kDa fragments . Further digestion of the 86-kDa amino-terminal fragment of the alpha-chain leads to the release of C5a or a C5a-like fragment that is biologically active for neutrophil activation . The fact that a potent chemotactic factor, i.e . C5a, can be generated from C5 by a proteinase derived from P . gingivalis suggests a recruiting mechanism for attracting neutrophils to the gingival lesion site in periodontal disease. J Biol Chem, 1992 Sep 5, 267(25), 18230 - 5 The capsular polysaccharide of Bacteroides fragilis comprises two ionically linked polysaccharides; Tzianabos AO et al.; Recently, we have shown that the capsular polysaccharide of Bacteroides fragilis NCTC 9343 is composed of an aggregate of two discrete large molecular weight polysaccharides (designated polysaccharides A and B) . Following disaggregation of this capsular complex by very mild acid treatment, high resolution NMR spectroscopy demonstrated that polysaccharides A and B consist of highly charged repeating unit structures with unusual substituent groups (Baumann, H., Tzianabos, A . O., Brisson, J.-R., Kasper, D.L., and Jennings, H.J . (1992) Biochemistry 31, 4081-4089) . Presently, we report that the capsular polysaccharide of B . fragilis represents a complex structure that is formed as a result of ionic interactions between polysaccharides A and B . Electron microscopy of immunogold-labeled organisms (with monoclonal antibodies specific for polysaccharides A and B) demonstrated that the two polysaccharides are co-expressed on the cell surface of B . fragilis . We have shown that the purified capsule complex is made up exclusively of polysaccharide A and polysaccharide B (no other macromolecular structure was detected) in a 1:3.3 ratio and that disaggregation of this complex into the native forms of the constituent polysaccharides could be accomplished by preparative isoelectric focusing . Structural analyses of the native polysaccharides A and B showed that they possessed the same repeating unit structures as the respective acid-derived polysaccharides . The ionic nature of the linkage between polysaccharides A and B was demonstrated by reassociation of the native polysaccharides to form an aggregated polymer comparable to the original complex . The distinctive composition of this macromolecule may provide a rationale for the unusual biologic properties associated with the B . fragilis capsular polysaccharide. J Bacteriol, 1992 Sep, 174(17), 5609 - 16 Location and characterization of genes involved in binding of starch to the surface of Bacteroides thetaiotaomicron; Tancula E et al.; Previous studies of starch utilization by the gram-negative anaerobe Bacteroides thetaiotaomicron have demonstrated that the starch-degrading enzymes are cell associated rather than extracellular, indicating that the first step in starch utilization is binding of the polysaccharide to the bacterial surface . Five transposon-generated mutants of B . thetaiotaomicron which were defective in starch binding (Ms-1 through Ms-5) had been isolated, but initial attempts to identify membrane proteins missing in these mutants were not successful . We report here the use of an immunological approach to identify four maltose-inducible membrane proteins, which were missing in one or more of the starch-binding mutants of B . thetaiotaomicron . Three of the maltose-inducible proteins were outer membrane proteins (115, 65, and 43 kDa), and one was a cytoplasmic membrane protein (80 kDa) . The genes encoding these proteins were shown to be clustered in an 8.5-kbp segment of the B . thetaiotaomicron chromosome . Two other loci defined by transposon insertions, which appeared to contain regulatory genes, were located within 7 kbp of the cluster of membrane protein genes . The 115-kDa outer membrane protein was essential for utilization of maltoheptaose (G7), whereas loss of the other proteins affected growth on starch but not on G7 . Not all of the proteins missing in the mutants were maltose regulated . We also detected two constitutively produced proteins (32 and 50 kDa) that were less prominent in all of the mutants than in the wild type . Both of these were outer membrane proteins. Minerva Stomatol, 1992 Sep, 41(9), 391 - 9 {Diabetic disease and periodontal disease . Diabetes and periodontopathy}; Gensini GF et al.; Diabetic patients have been reported to be more susceptible to gingivitis and periodontitis than healthy subjects, and these diseases are commonly considered to be oral complications of diabetes . The influence of diabetes on the onset and development of periodontal disease has been studied for many years but clear agreement is still lacking on the nature of the relationship between diabetes and these oral disorders . In fact recent observational epidemiological studies suggest that diabetes should not be considered as the direct cause of periodontal disease but rather as a systemic promoting factor, able to produce conditions suitable for local agents producing gingivitis and periodontitis . The overriding oral problem in diabetes is infection, like with any of the dermal lesions in the diabetic . In fact periodontal disease is caused by specific bacteria (Bacteroides Gingivalis, Actinobacillus actinomycetemcomitans) growing in the periodontal pocket so that the bacterial products such as histolytic enzymes, endotoxins or exotoxins may exert a direct effect . Particular attention has been directed to the neutrophils and to their role in antibacterial defense . In fact a reduced phagocytosis, leukotaxis and leucocyte index have been reported in neutrophils from diabetics . The careful metabolic control was reported by most of the Authors to lower the incidence and to reduce the severity of periodontal disease . This may be related both to the improvement in leukocyte function and to a change in gingival fluid rendering it less suitable for bacterial growth . In diabetics also local factors, such as decreased pH of salivary fluid and a reduced salivary flow, seem to play an important role.(ABSTRACT TRUNCATED AT 250 WORDS) J Antimicrob Chemother, 1992 Sep, 30(3), 295 - 301 Antibiotic sensitivity of ribosomes from wild-type and clindamycin resistant Bacteroides vulgatus strains; Jimenez-Diaz A et al.; The sensitivity to different antibiotics of in-vitro polyuridylic acid-dependent polypeptide synthesizing system from Bacteroides vulgatus RYC18F6 and two clindamycin-resistant derivatives was studied . The ribosomes from the resistant strains were not affected by concentrations of up to 0.1 mM clindamycin and lincomycin . In contrast, streptogramin B was found to cause strong stimulation of the clindamycin-resistant polymerizing systems . The modified ribosomes from the resistant strains were more sensitive to other antibiotics like sparsomycin and chloramphenicol . The data indicate that resistance in these B . vulgatus mutant strains is due to alteration of the ribosome structure. Rehabil Nurs, 1992 Sep-Oct, 17(5), 244 - 5, 255 Metronidazole use in malodorous skin lesions; Rice TT; Malodorous skin lesions (primarily fungating tumors and decubitus ulcers) can be extremely resistant to efforts to control their odors . The offending bacteria appear to be anaerobes, specifically the Bacteroides species . Topical metronidazole has shown promise for odor control without the cost or side effects of a systemic drug . In various anecdotal reports, lesions in patients treated with topical metronidazole were virtually free of odor within 24 hours, and in some cases, slight improvements in wound appearance and pain also were noted . The encouraging results of these initial experiences with topical metronidazole warrant further study for its efficacy in reducing skin lesion odor. Appl Environ Microbiol, 1992 Sep, 58(9), 2764 - 70 Genetic analysis of a locus on the Bacteroides ovatus chromosome which contains xylan utilization genes; Weaver J et al.; Bacteroides ovatus, a gram-negative obligate anaerobe found in the human colon, can utilize xylan as a sole source of carbohydrate . Previously, a 3.8-kbp segment of B . ovatus chromosomal DNA, which contained genes encoding a xylanase (xylI) and a bifunctional xylosidase-arabinosidase (xsa), was cloned, and expression of the two genes was studied in Escherichia coli (T . Whitehead and R . Hespell, J . Bacteriol . 172:2408-2412, 1990) . In the present study, we have used segments of the cloned region to construct insertional disruptions in the B . ovatus chromosomal locus containing these two genes . Analysis of these insertional mutants demonstrated that (i) xylI and xsa are probably part of the same operon, with xylI upstream of xsa, (ii) the true B . ovatus promoter was not cloned on the 3.5-kbp DNA fragment which expressed xylanase and xylosidase in E . coli, (iii) there is at least one gene upstream of xylI which could encode an arabinosidase, and (iv) xylosidase rather than xylanase may be a rate-limiting step in xylan utilization . Insertional mutations in the xylI-xsa locus reduced the rate of growth on xylan, but the concentration of residual sugars at the end of growth was the same as that with the wild type . Thus, a slower rate of growth on xylan was not accompanied by less extensive digestion of xylan . Mutants in which xylI had been disrupted still expressed some xylanase activity . This second activity was associated with membranes and produced xylose from xylan, whereas the xylI gene product partitioned primarily with the soluble fraction and produced xylobiose from xylan. J Infect, 1992 Sep, 25(2), 211 - 4 Metronidazole-resistant Bacteroides fragilis wound infection; O'Donoghue MA et al.; We report the isolation of metronidazole-resistant Bacteroides fragilis from a post-operative wound abscess in a 72-year-old woman who had not been treated with metronidazole during the preceding 9 months . The case illustrates the need for caution when identifying anaerobes on the basis of metronidazole sensitivity. Antimicrob Agents Chemother, 1992 Sep, 36(9), 2051 - 3 Susceptibilities of members of the Bacteroides fragilis group to 11 antimicrobial agents; Horn R et al.; The susceptibilities of 200 clinical isolates of the Bacteroides fragilis group to 11 antimicrobial agents were determined by the broth microdilution method of the National Committee for Clinical Laboratory Standards . All isolates were susceptible to imipenem and ticarcillin-clavulanic acid . The rates of resistance to cefoxitin and clindamycin were low (4 and 6%, respectively), while those to ceftizoxime and cefotetan were higher (10.5 and 24%, respectively). J Clin Microbiol, 1992 Sep, 30(9), 2408 - 14 Restriction endonuclease analysis and ribotyping differentiate genital and nongenital strains of Bacteroides ureolyticus; Akhtar N et al.; Thirty-three clinical isolates from male nongonococcal urethritis and 28 isolates from soft tissue infections and ulcers were identified as Bacteroides ureolyticus by conventional bacteriological tests and were compared with five reference strains of the species . Whole-cell proteins from these clinical isolates and the reference strains were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) . The majority of the strains from the two sources could be divided into five different groups, named phenons I to V; phenons I to IV have been described previously by others, while phenon V has been described recently by us . Digestion of chromosomal DNA from 16 of the clinical isolates (including strains representative of each of the five SDS-PAGE phenons) and the five reference strains was attempted with restriction endonucleases EcoRI, PstI, SmaI, and HindIII . After electrophoresis in agarose gels, good digestion was observed with HindIII only, and 12 different banding patterns (restriction endonuclease analysis {REA} profiles) were obtained for the 19 strains digested; one nongonococcal urethritis isolate and one reference strain did not show any digestion . From the agarose gels, HindIII-digested fragments of DNA were transferred to nylon membranes by use of vacuum blotting and subjected to hybridization with 32P-labelled 16S-23S rRNA from Escherichia coli . The resultant pattern of bands (ribotypes), which depends on the restriction fragment length polymorphisms in the rRNA genes, was used as a measure of genomic variation within the species . In total, 13 different ribotypes were obtained for the 19 strains . For some strains, good correlation was achieved among the SDS-PAGE phenons, REA profiles, and ribotypes . However, for others, REA analysis and ribotyping were able to discriminate between strains which shared the same SDS-PAGE phenon . Interestingly, these two techniques of DNA characterization were able to differentiate between isolates from the genital tract and those associated with soft tissue infections and ulcers. J Appl Bacteriol, 1992 Sep, 73(3), 243 - 50 Two beta-glucosidase activities in Fibrobacter succinogenes S85; Buchanan CJ et al.; Few bacteria are capable of degrading crystalline cellulose but there is considerable interest in the properties of enzyme systems with this capability . In the bovine and ovine rumen the principal cellulolytic bacterium is Fibrobacter (formerly Bacteroides) succinogenes . The cellulase system of this organism is composed of multiple enzyme components, including a constitutive and cell-associated beta-glucosidase active against cellobiose . The properties of the beta-glucosidase activity have been investigated with the chromogenic substrate p-nitrophenyl beta-D-glucoside (pNPG) . Hydrolytic activity against pNPG was located primarily in the cytoplasm and the cytoplasmic membrane but showed a gradual migration to the periplasm during growth on either glucose or cellobiose . Activity against cellobiose was found in the periplasm in significant amounts in all growth phases . Of the beta-glucosides tested, only cellobiose and pNPG were hydrolysed by crude cell extracts . In the presence of cellobiose, however, the rate of hydrolysis of pNPG was stimulated up to 10-fold, and extracts hydrolysed methylumbelliferyl beta-D-glucoside, 5-bromo-4-chloro-3-indolyl beta-D-glucoside, arbutin and aesculin . Activities against pNPG in the presence and absence of cellobiose displayed similar instability in the presence of oxygen; both were stabilized by dithiothreitol and the temperature and pH optima were identical . A significant proportion of the membrane-associated beta-glucosidase was released by treatment with 0.3 mol/1 KCl, and fractionation by chromatography on CM-cellulose showed the presence of two activities against pNPG, only one of which was stimulated by cellobiose. J Med Microbiol, 1992 Sep, 37(3), 165 - 75 The isolation and characterisation of a major outer-membrane protein from Bacteroides distasonis; Wexler HM et al.; An outer-membrane protein (OMP) was isolated from a clinical strain of Bacteroides distasonis . Changes in growth media did not appreciably affect the appearance of this protein in crude outer-membrane preparations examined by SDS-PAGE . However, the proportion of the protein relative to other OMPs was greater in 24-h cultures than in 48-h cultures . The protein could not be readily solubilised by various conventional detergent extraction techniques but treatment of the insoluble material at 100 degrees C with SDS released the protein, as did overnight extraction at 37 degrees C with SDS . This OMP was heat-modifiable, and thus was similar to the OmpA protein of Escherichia coli, with a faster mobility on SDS-PAGE when solubilised at 25 degrees C than at 100 degrees C . The critical temperature for conversion was between 80 degrees C and 90 degrees C . Because of the characteristic heat-modifiability, the protein was called B . distasonis HMP-1 (heat modifiable protein-1) . Overnight exposure to EDTA or NaCl at 37 degrees C favoured conversion of the 25 degrees C form to the 100 degrees C form . In intact cells, the protein was labelled by a cell-surface radio-iodination procedure, and thus is at least partially exposed at the cell surface . No reactions between the B . distasonis HMP-1 and antibodies to either E . coli OmpA or E . coli porin were found by Western blot analysis . A B . distasonis OM preparation containing predominantly HMP-1 had pore-forming ability in a liposome assay . This study is the first report of the isolation and characterisation of a heat-modifiable OMP in Bacteroides, and it is the first description of pore-forming activity in a Bacteroides OM fraction. Infect Immun, 1992 Sep, 60(9), 3579 - 85 Humoral response to Porphyromonas (Bacteroides) gingivalis in rats: time course and T-cell dependence; Katz J et al.; In this study, we describe the time course and T-cell dependence of the serum antibody response to the periodontopathogen Porphyromonas (Bacteroides) gingivalis in an experimental rat model . Normal Fischer rats were challenged by a local injection of P . gingivalis (2 x 10(8) bacteria) into gingival tissue or by the administration of a similar number of bacteria by the intravenous (i.v.) route on days 0, 2, and 4 . Serum antibody activity was detected within 1 week and peaked at 8 weeks after gingival challenge . A similar but lower response was seen for rats challenged by the i.v . route . The response in both groups of rats was mainly of the immunoglobulin G (IgG) isotype; some IgM but no IgA antibody activity was detected . Analysis of the IgG subclass revealed mainly IgG2c in animals challenged locally in the gingiva with P . gingivalis, whereas IgG2b predominated in rats challenged by the i.v . route . The importance of T cells in the response was established by demonstrating the absence of serum IgG antibodies in nude rats after a local challenge of gingival tissue with P . gingivalis . Nude rats given purified splenic T cells from normal rats immunized systemically with P . gingivalis prior to a local gingival challenge showed a rapid appearance of serum antibody activity that peaked between 4 and 6 weeks . This initial peak occurred 2 to 4 weeks earlier than that seen in normal animals . Fluorescence-activated cell sorter analysis of splenic lymphoid cells from these nude rats revealed a helper T-cell population . The levels of serum IgG antibodies in nude rats given nonimmune T cells rose slowly, and the antibodies were mainly of the IgG2a and IgG2b subclasses . Nude rats given immune T cells showed a rapid increase primarily in IgG2b antibody levels following a local gingival challenge . These findings suggest that the immune helper T-cells contributed to the rapid development of the response to P . gingivalis . Furthermore, it is likely that the IgG subclass response to P . gingivalis in these nude rats was related to the splenic origin of the T cells used for adoptive transfer. FEMS Microbiol Lett, 1992 Aug 15, 74(2-3), 207 - 12 Isolation of a ferritin from Bacteroides fragilis; Rocha ER et al.; A ferritin was isolated from the obligate anaerobe Bacteroides fragilis . Estimated molecular masses were 400 kDa for the holomer and 16.7 kDa for the subunits . A 30-residue N-terminal amino acid sequence was determined and found to resemble the sequences of other ferritins (human H-chain ferritin, 43% identity; Escherichia coli gen-165 product, 37% identity) and to a lesser degree, bacterioferritins (E . coli bacterioferritin, 20% identity) . The protein stained positively for iron, and incorporated 59Fe when B . fragilis was grown in the presence of {59Fe}citrate . However, the isolated protein contained only about three iron atoms per molecule, and contained no detectable haem . This represents the first isolation of a ferritin protein from bacteria . It may alleviate iron toxicity in the presence of oxygen. FEMS Microbiol Lett, 1992 Aug 15, 74(2-3), 133 - 6 Characterization of restriction endonuclease BfrBI from Bacteroides fragilis strains BE3 and AIP 10006; Azeddoug H et al.; A new type II restriction endonuclease, named BfrBI, was detected in two strains of Bacteroides fragilis, BE3 and AIP 10006 (NCTC 9343T) . The enzyme BfrBI, an isoschizomer of NsiI and AvaIII, recognized the hexanucleotide sequence {5'-ATG decreases CAT-3'}, with a cleavage site generating blunt ends. FEMS Microbiol Lett, 1992 Aug 15, 74(2-3), 163 - 8 Application of polymerase chain reaction with arbitrary primer (AP-PCR) to strain identification of Porphyromonas (Bacteroides) gingivalis; Menard C et al.; Several molecular methods are currently available for identification and discrimination of bacterial strains within the same species, which vary in efficiency and required labour . Here we applied a novel method for fingerprinting genomes, called arbitrarily primed PCR (AP-PCR), to the delineation of strains within the species Porphyromonas gingivalis . Using a single primer on a set of nine strains, nine simple distinct banding patterns, indicative of genetic polymorphism, were observed . Common amplicons and amplicons shared by only some strains were also observed, the latter suggesting that AP-PCR can be used to generate polymorphic markers . Genomic fingerprinting obtained by AP-PCR was independent of the quality of DNA . Assays performed directly using whole cells as a source of DNA template indicated that AP-PCR from colony is a quick, simple and accurate procedure. FEMS Microbiol Lett, 1992 Aug 1, 74(1), 1 - 5 Cloning of a Bacteroides fragilis chromosomal determinant coding for 5-nitroimidazole resistance; Haggoud A et al.; Strain BF8 is a plasmid-free Bacteroides fragilis, resistant to 5-nitroimidazole (5-Ni) antibiotics (metronidazole, ornidazole and tinidazole) . The resistance was transferable by conjugation into Bacteroides fragilis BF638R . The total DNA of a Nir transconjugant was used for the construction of a Sau3A genomic library in a B . fragilis cloning vector pFK707 delta H1 (4.2 kb) . By electrotransformation of strain BF638R, a recombinant plasmid containing an insert of 5.4 kb was obtained which conferred to the host strain the resistance to 5-Ni . The physic