J Rheumatol, 2002 Jun, 29(6), 1244 - 51 Accelerated alveolar bone loss in HLA-b27 transgenic rats: an adult onset condition; Tatakis DN et al.; OBJECTIVE: Patients with arthritis and Crohn's disease may be more susceptible to periodontitis associated alveolar bone loss (ABL) . HLA-B27 transgenic (TG) rats spontaneously develop arthritis and colitis . Based on the hypothesis that TG rats would also be susceptible to ABL, we compared the naturally occurring ABL in TG and Fischer 344 wild-type (WT) rats . METHODS: Eighteen TG and 18 WT virgin female rats were used . Pairs (I TG, I WT) were housed in suspended wire cages . At age 2.6, 6, and 11 months, 8, 5, and 5 pairs were sacrificed, respectively . ABL was measured as exposed molar root surface area (mm2) . Western blotting was used for analysis of serum reactivity against bacteria associated with arthritis, colitis, and periodontitis development . RESULTS: At 2.6 months of age, there was no difference in ABL between TG and WT rats . At 6 and 11 months ABL was significantly greater in TG animals by 28% and 53%, respectively . For TG rats, ABL was significantly different between the 3 age groups . For WT rats, ABL was not significantly different between 6 and 11 months . Western blotting revealed distinct TG serum reactivity against extracts of Bacteroides vulgatus, B . fragilis, Prevotella intermedia, and to a lesser extent against extracts of B . forsythus . CONCLUSION: The accelerated ABL in HLA-B27 TG rats is an adult onset condition, independent of husbandry conditions or parity status . HLA-B27 rats exhibit strong immunoreactivity against bacteria implicated in arthritis, colitis, and periodontitis. Carbohydr Res, 2002 Jun 12, 337(12), 1095 - 111 Synthesis and utility of sulfated chromogenic carbohydrate model substrates for measuring activities of mucin-desulfating enzymes; Clinch K et al.; A chromogenic substrate, 4-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside 6-sodium sulfate was synthesized and used in combination with beta-N-acetylhexosaminidase for detection of the sulfatase, MdsA, by release of 4-nitrophenol . MdsA was originally isolated from the bacterium Prevotella strain RS2 and is believed to be involved in desulfation of sulfomucins, major components of the mucus barrier protecting the human colon surface . The exo nature of the MdsA sulfatase was indicated by its inability to de-esterify the disaccharide 4-nitrophenyl beta-D-galactopyranosyl-(1-->4)-2-acetamido-2-deoxy-beta-D-glucopyranoside 6-sodium sulfate . This latter compound was prepared from monosaccharide precursors by two different methods, the shorter requiring just six steps from 4-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside and giving an overall yield of 26.4% . The syntheses of 4-nitrophenyl beta-D-galactopyranoside 3-triethylammonium sulfate and 6-triethylammonium sulfate and their use in combination with beta-galactosidase as chromogenic substrates for detecting Bacteroides fragilis sulfatases with different specificities was also demonstrated. Annu Rev Nutr, 2002, 22, 283 - 307 Epub 2002 Apr 04. How host-microbial interactions shape the nutrient environment of the mammalian intestine; Hooper LV et al.; Humans and other mammals are colonized by a vast, complex, and dynamic consortium of microorganisms . One evolutionary driving force for maintaining this metabolically active microbial society is to salvage energy from nutrients, particularly carbohydrates, that are otherwise nondigestible by the host . Much of our understanding of the molecular mechanisms by which members of the intestinal microbiota degrade complex polysaccharides comes from studies of Bacteroides thetaiotaomicron, a prominent and genetically manipulatable component of the normal human and mouse gut . Colonization of germ-free mice with B . thetaiotaomicron has shown how this anaerobe modifies many aspects of intestinal cellular differentiation/gene expression to benefit both host and microbe . These and other studies underscore the importance of understanding precisely how nutrient metabolism serves to establish and sustain symbiotic relationships between mammals and their bacterial partners. Int J Syst Evol Microbiol, 2002 May, 52(Pt 3), 841 - 9 Reclassification of Bacteroides forsythus (Tanner et al . 1986) as Tannerella forsythensis corrig., gen . nov., comb . nov; Sakamoto M et al.; The characteristics of the fusiform species Bacteroides forsythus, isolated from human periodontal pockets, were examined . 165 rDNA sequence analysis confirmed that B . forsythus was not a species within the genus Bacteroides sensu stricto . Although B . forsythus was phylogenetically related to Bacteroides distasonis and Bacteroides merdae in the phylogenetic tree, the ratio of anteiso-15:0 to iso-15:0 in whole-cell methanolysates of B . forsythus was different from those of B . distasonis, B . merdae and other Bacteroides species . B . forsythus did not grow on medium containing 20% bile, but members of the Bacteroides fragilis group did . B . forsythus was the only species tested that was trypsin-positive in API ZYM tests . The dehydrogenase enzyme pattern was of no use for the differentiation of B . forsythus and the B . fragilis group . On the basis of these data, a new genus, Tannerella, is proposed for Bacteroides forsythus, with one species, Tannerella forsythensis corrig., gen . nov., comb . nov . The type strain of Tannerella forsythensis is JCM 10827T (= ATCC 43037T). FEMS Microbiol Lett, 2002 May 21, 211(1), 7 - 11 Altamira cave Paleolithic paintings harbor partly unknown bacterial communities; Schabereiter-Gurtner C et al.; Since it has been reported that microorganisms can affect painting pigments, Paleolithic painting microbiology deserves attention . The present study is the first report on the bacterial colonization of the valuable Paleolithic paintings in the famous Altamira cave (Spain) . One sample taken from a painting area in the Polychromes Hall was analyzed culture-independently . This was the first time microbiologists were allowed to take sample material directly from Altamira paintings . Identification methods included PCR amplification of 16S rRNA genes (16S rDNA) and community fingerprinting by denaturing gradient gel electrophoresis (DGGE) . The applied approach gave insight into a great bacterial taxonomic diversity, and allowed the detection of unexpected and unknown bacteria with potential effects on the conservation of the painting . Regarding the number of 29 visible DGGE bands in the community fingerprint, the numbers of analyzed clones described about 72% of the phylogenetic diversity present in the sample . Thirty-eight percent of the sequences analyzed were phylogenetically most closely related to cultivated bacteria, while the majority (62%) were most closely related to environmental 16S rDNA clones . Bacteria identified in Altamira were related with sequence similarities between 84.8 and 99.4% to members of the cosmopolitan Proteobacteria (52.3%), to members of the Acidobacterium division (23.8%), Cytophaga/Flexibacter/Bacteroides phylum (9.5%), green non-sulfur bacteria (4.8%), Planctomycetales (4.8%) and Actinobacteria (4.8%) . The high number of clones most closely related to environmental 16S rDNA clones showed the broad spectrum of unknown and yet to be cultivated bacteria in Altamira cave. Ned Tijdschr Tandheelkd, 1992 Sep, 99(9), 341 - 2 {Identification of bacteria using DNA probes}; Vanderfaeillie A; Since the microbial specificity of periodontal diseases is well established, having a valid microbial diagnostic test is essential for a correct and a coherent treatment planning . DNA probe will be used to identify and quantify the oral pathogens, most commonly associated with periodontitis . This test utilizes innovative DNA probe technology to identify unique segments of DNA in each of the following bacteria: Bacteroides gingivalis, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Wollinella recta, Fusobacterium nucleatum and the spirochete, Treponema denticola. Biochemistry, 2002 May 28, 41(21), 6615 - 30 Insights into the structure and dynamics of the dinuclear zinc beta-lactamase site from Bacteroides fragilis; Suarez D et al.; Herein, we report quantum chemical calculations and molecular dynamics (MD) simulations of the dinuclear form of the Bacteroides fragilis zinc beta-lactamase . We studied four different configurations which differ in the protonation state of the Asp103 residue and in the presence or absence of a Zn1-OH-Zn2 bridge . The flexibility of the Zn1-OH-Zn2 bridge was studied by means of quantum mechanical (QM) calculations on cluster models while the relative stabilities of the different configurations were estimated from QM linear scaling calculations on the enzyme . Contacts between important residues (Cys104, Asp69, Lys185, etc.), the solvation of the zinc ions, and the conformation of the active site beta-hairpin loop were characterized by the MD analyses . The influence of the buried sodium ion close to the Zn2 position was investigated by carrying out a secondary simulation where the sodium ion was replaced with an internal water molecule . The comparative structural analyses among the different MD trajectories augmented with energetic calculations have demonstrated that the B . fragilis protein efficiently binds the internal Na(+) ion observed crystallographically . Moreover, we found that when Asp103 is unprotonated, a rigid Zn1-OH-Zn2 bridge results, while for neutral Asp103, a fluctuating Zn1-Zn2 distance was possible via the breaking and formation of the Zn1-OH-Zn2 bridge . The mechanistic implications of these observations are discussed in detail. Clin Exp Immunol, 2002 May, 128(2), 238 - 44 Effect of Fusobacterium nucleatum on the T and B cell responses to Porphyromonas gingivalis in a mouse model; Gemmell E et al.; T cell cytokine profiles and specific serum antibody levels in five groups of BALB/c mice immunized with saline alone, viable Fusobacterium nucleatum ATCC 25586, viable Porphyromonas gingivalis ATCC 33277, F . nucleatum followed by P . gingivalis and P . gingivalis followed by F . nucleatum were determined . Splenic CD4 and CD8 cells were examined for intracytoplasmic interleukin (IL)-4, interferon (IFN)-gamma and IL-10 by dual colour flow cytometry and the levels of serum anti-F . nucleatum and anti-P . gingivalis antibodies determined by an ELISA . Both Th1 and Th2 responses were demonstrated by all groups, and while there were slightly lower percentages of cytokine positive T cells in mice injected with F . nucleatum alone compared with the other groups immunized with bacteria, F . nucleatum had no effect on the T cell production of cytokines induced by P . gingivalis in the two groups immunized with both organisms . However, the percentages of cytokine positive CD8 cells were generally significantly higher than those of the CD4 cells . Mice immunized with F . nucleatum alone had high levels of serum anti-F . nucleatum antibodies with very low levels of P . gingivalis antibodies, whereas mice injected with P . gingivalis alone produced anti-P . gingivalis antibodies predominantly . Although the levels of anti-F . nucleatum antibodies in mice injected with F . nucleatum followed by P . gingivalis were the same as in mice immunized with F . nucleatum alone, antibody levels to P . gingivalis were very low . In contrast, mice injected with P . gingivalis followed by F . nucleatum produced equal levels of both anti-P . gingivalis and anti-F . nucleatum antibodies, although at lower levels than the other three groups immunized with bacteria, respectively . Anti-Actinobacillus actinomycetemcomitans, Bacteroides forsythus and Prevotella intermedia serum antibody levels were also determined and found to be negligible . In conclusion, F . nucleatum immunization does not affect the splenic T cell cytokine response to P . gingivalis . However, F . nucleatum immunization prior to that of P . gingivalis almost completely inhibited the production of anti-P . gingivalis antibodies while P . gingivalis injection before F . nucleatum demonstrated a partial inhibitory effect by P . gingivalis on antibody production to F . nucleatum . The significance of these results with respect to human periodontal disease is difficult to determine . However, they may explain in part differing responses to P . gingivalis in different individuals who may or may not have had prior exposure to F . nucleatum . Finally, the results suggested that P . gingivalis and F . nucleatum do not induce the production of cross-reactive antibodies to other oral microorganisms. FEMS Microbiol Lett, 2002 Feb 5, 207(2), 193 - 7 Physical and genetic map of the Bacteroides fragilis YCH46 chromosome; Kuwahara T et al.; The chromosome of Bacteroides fragilis strain YCH46 was shown to be a single circular DNA molecule of about 5.3 Mb having 16 NotI, seven AscI, and six I-CeuI sites . A physical map of the chromosome was constructed by four independent experimental approaches: linking clone analysis, cross-Southern hybridization, partial restriction digestion, and two-dimensional pulsed-field gel electrophoresis . Six rRNA operons and 10 known genes were localized on the physical map. Infect Immun, 2002 May, 70(5), 2463 - 71 Diversity of the metalloprotease toxin produced by enterotoxigenic Bacteroides fragilis; Wu S et al.; Enterotoxigenic Bacteroides fragilis (ETBF) strains produce a 20-kDa zinc metalloprotease toxin (BFT) associated with diarrheal disease of animals, young children, and adults . BFT stimulates secretion in intestinal loops in vivo and modifies epithelial cell morphology in vitro . The B . fragilis toxin (bft) gene from ETBF strain 86-5443-2-2 (piglet; bft-2) revealed significant nucleotide and predicted amino acid differences when compared to the bft gene from ETBF strain VPI 13784 (lamb; bft-1) . This study compares BFT-1 and BFT-2, respectively, produced by ETBF strains VPI 13784 and 86-5443-2-2 purified using the Van Tassell method (38) and a modified purification scheme described herein . Multiple differences in the protein toxins produced by these ETBF strains were identified . First, purified BFT-1 eluted from a high-resolution anion-exchange column (Mono Q) at 0.22 +/- 0.005 M NaC1 versus 0.18 +/- 0.001 M NaC1 for BFT-2 (P < 0.001) . Second, BFT-1 and BFT-2 exhibited different electrophoretic mobilities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and reverse-phase fast protein liquid chromatography . Third, each BFT reacted with greater specificity to homologous rather than heterologous antisera . Fourth, BFT-2 had modest, but consistently, greater biological activity than BFT-1 when tested on HT29/C1 cells (P < or = 0.01) . Together, these data indicate that these ETBF strains produce two distinct isotypes of BFT, termed BFT-1 (VPI 13784 BFT) and BFT-2 (86-5443-2-2 BFT) to recognize the order in which the proteins were purified and genetic sequences identified . The modified purification scheme described in this report yields about two to three times more purified BFT protein than previous protocols and is less time consuming. Lab Anim, 2002 Apr, 36(2), 200 - 8 PCR for the detection of Streptobacillus moniliformis; Boot R et al.; Streptobacillus moniliformis is a Gram-negative bacterium found in various laboratory animal species and is the cause of rat bite fever and Haverhill fever in man . In order to evaluate a polymerase chain reaction (PCR) for the detection of this zoonotic bacterium in animal tissues a set of primers was designed based on the DNA base sequence of part of the 16S rRNA gene from 11 S . moniliformis strains . The PCR detected as few as 2-6 copies of S . moniliformis DNA . A 296 bp DNA fragment was amplified from S . moniliformis strains from rodents, humans and turkeys . Amplicons of about the same size were obtained from Fusobacterium necrogenes and Sebaldella (Bacteroides) termitidis but Bfa I treatment of these amplicons did not result in the S . moniliformis specific 130 bp DNA fragment . The in silico evaluation of 14 additional Fusobacterium spp . and 12 unculturable phytoplasmas indicated that none is likely to give rise to confusing amplicons or DNA fragments . The PCR detected S . moniliformis infection in all four orally- and four intravenously-infected C57BL/6 mice and the bacterium was cultured from all but one mouse . The PCR detected S . moniliformis infection in all 12 orally-infected WU rats, and in five of eight rats exposed to natural infection . Enzyme linked immunosorbent assay (ELISA) and PCR were equally successful in detecting infection in rats but S . moniliformis was not detected by using culture. J Clin Periodontol, 2002 Mar, 29(3), 233 - 9 Clinical, genetic and microbiological findings in a Brazilian family with aggressive periodontitis; Trevilatto PC et al.; BACKGROUND/AIM: Aggressive periodontitis comprises a group of rapidly progressive forms of periodontitis . Besides bacteria, a high level of subject susceptibility must be involved in the expression of disease . In the present study, we report the clinical, microbiological and genetic profile of a 14-individual family with aggressive periodontitis . METHOD: PCR was utilized to detect pathogenic bacteria of affected sites . DNA was obtained from epithelial cells through a mouthwash with 3% glucose and scrapping of the oral mucosa . RFLP-PCR was used to analyze cytokine genetic polymorphisms . RESULTS: Localized aggressive periodontitis was diagnosed for an 18-year-old systemically healthy non-smoking proband, with siblings displaying aggressive periodontitis . Bacteroides forsythus and Treponema denticola were the most frequent pathogens . The proband presented Actinobacillus actinomycetemcomitans and detectable levels of Porphyromonas gingivalis, Bacteroides forsythus and Treponema denticola . Allele 2 of IL-1alpha (-889) polymorphism was found in all individuals as well as allele 1 of the IL-1beta (+3953) gene . Alleles 1 and 2 (50 % each) of IL-1beta (-511), allele 1 of TNF-alpha (-308) and allele 2 (in homo or heterozygosity) of IL-RN (intron 2) gene were present . CONCLUSION: The results show that the present microbiological and genetic parameters were not relevant for the prediction of periodontitis susceptibility in this family. Oral Microbiol Immunol, 2002 Apr, 17(2), 125 - 8 Bacteroides forsythus hemagglutinin is inhibited by N-acetylneuraminyllactose; Murakami Y et al.; Bacteroides forsythus, which has been recognized as a pathogen associated with periodontitis, produces a hemagglutinin . The hemagglutinin was localized in the envelope of B . forsythus . The hemagglutinating activity was inhibited by lactose at concentrations as low as 1 mM, and by L-arginine and L-lysine at concentrations of 100 mM . N-Acetylneuraminyllactose (NeuAc-lactose) was at least 100 times more potent an inhibitor than lactose, as it completely inhibited the hemagglutination at concentrations below 10 microM . This is similar to the Helicobacter pylori hemagglutinin . The hemagglutinin was heat-labile, and resistant to treatment with proteases such as trypsin . A specific antibody raised against one of the S-layer proteins that are major species-specific proteins had no inhibitory effect on the hemmaglutination . These results suggest that the NeuAc-lactose-sensitive adhesin of B . forsythus may play an important role in colonization in the oral cavity. Oral Microbiol Immunol, 2002 Apr, 17(2), 85 - 8 High prevalence of cfxA beta-lactamase in aminopenicillin-resistant Prevotella strains isolated from periodontal pockets; Fosse T et al.; This prospective study was designed to investigate amoxicillin-resistant oral anaerobes, and to identify their beta-lactamase-encoding genes . Three subgingival bacterial samples were collected from 12 patients suffering from periodontitis . One to seven beta-lactamase-producing strains were obtained from each patient, mostly belonging to the Prevotella genus (Bacteroides eggerthii, 2/35 strains; Prevotella sp., 33/35 strains) . PCR assays were used to detect cfxA and cepA/cblA, the genes encoding class A/group2e beta-lactamases previously described in the Bacteroides fragilis group . The present investigation confirmed the role of Prevotella species as beta-lactamase producers in periodontal pockets . Additionally, this PCR screening showed (1): the high prevalence of CfxA beta-lactamase production by aminopenicillin-resistant Prevotella (32/33: 97.0% positive strains) vs . cepA/cblA (1/33: 3.0% positive strains), and (2) the presence of cfxA in the periodontal reservoir in the absence of antimicrobial therapy during the previous 6 months. J Periodontol, 2002 Mar, 73(3), 283 - 8 Periodontopathic bacteria in young healthy subjects of different ethnic backgrounds in Los Angeles; Sirinian G et al.; BACKGROUND: The present study determined risk indicators for oral colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola in 150 children and adolescents, 4 to 16 years of age, living in Los Angeles, California . METHODS: Fifty Caucasians, 50 Hispanics, and 50 Asian-Americans completed a questionnaire on demographic characteristics . 16S rRNA-based polymerase chain reaction identification was employed to determine the presence of test bacteria in unstimulated saliva . Step-wise logistic regression analysis identified explanatory variables (risk indicators) accounting for the salivary presence of periodontopathic bacteria . RESULTS: A . actinomycetemcomitans occurred in 15%, P . gingivalis in 15%, B . forsythus in 14%, and T . denticola in 18% of all subjects . Two or more pathogens were detected in 20% of Hispanic subjects and in 12% of Asian-American subjects but not in any Caucasians (P = 0.0005, chi square test) . However, no stable multivariate model including ethnicity was found for multiple pathogens . Risk for harboring any pathogens increased with the length of time lapse from last dental visit (odds ratio {OR}, 4.46; 95% confidence interval {CI}, 1.83 to 12.21), and decreased with higher education level of the mother (OR, 0.258; 95% CI, 0.052 to 0.875) . Risk for harboring 2 or more periodontal pathogens decreased with the years the parents had resided in the United States (OR, 0.95; 95% CI, 0.901 to 0.992) . Risk for harboring A . actinomycetemcomitans decreased as the number of years the parents had resided in the United States increased (OR, 0.91; 95% CI, 0.86 to 0.95), and decreased with higher income level of the father (OR, 0.201; 95% CI, 0.038 to 0.948) . Girls were at higher risk for harboring P . gingivalis (OR, 2.55; 95% CI, 1.02 to 7.03), but at lower risk for carrying T . denticola (OR, 0.42; 95% CI, 0.17 to 0.98) . CONCLUSIONS: This study showed that salivary occurrence of periodontopathic bacteria in young individuals was related to the length of time the parents had lived in the United States, education level of the mother, length of time since last dental visit, and gender, but apparently not to ethnicity per se. J Clin Periodontol, 2002 Feb, 29(2), 152 - 8 Distribution of erm(F) and tet(Q) genes in 4 oral bacterial species and genotypic variation between resistant and susceptible isolates; Chung WO et al.; BACKGROUND: Bacteroides forsythus, Porphyromonas gingivalis and Prevotella intermedia are Gram-negative anaerobic bacteria that are currently considered potential periopathogens . Prevotella nigrescens has recently been separated from P . intermedia and its role in periodontitis is unknown . The erm(F) gene codes for an rRNA methylase, conferring resistance to macrolides, lincosamides and streptogramin B (MLSB), and the tet(Q) gene for a ribosomal protection protein, conferring resistance to tetracycline . The presence of these resistance genes could impair the use of antibiotics for therapy . PURPOSE: The aim of this study was to determine the carriage of erm(F) and tet(Q), and genetic variability of 12 Porphyromonas gingivalis, 10 Prevotella intermedia, 25 Prevotella nigrescens and 17 Bacteroides forsythus isolates from 9 different patient samples . METHODS: We used polymerase chain reaction (PCR) for detecting antibiotic resistance genes, and pulsed-field gel electrophoresis (PFGE) for detecting genetic variability among the isolates . RESULTS: Thirty-one (48%) isolates were resistant to both erythromycin and tetracycline and carried the erm(F) and tet(Q) genes, eight (13%) were tetracycline resistant and carried the tet(Q) gene, 9 (14%) were erythromycin resistant and carried the erm(F) gene, and 12 (19%) isolates did not carry antibiotic resistance genes . PFGE was used to compare isolates from the same patient and isolates from different patient samples digested with XbaI . No association was found between antibiotic resistance gene carriage and PFGE patterns in any species examined . All isolates of the same species from the same patient had highly related or identical PFGE patterns . Isolates of same species from different patients had unique PFGE pattern for each species tested . CONCLUSION: All isolates of the same species from any one patient were genetically related to each other but distinct from isolates from other patients, and 66% of the patients carried antibiotic resistant isolates, which could impair antibiotic therapy. J Bacteriol, 2002 Apr, 184(7), 1895 - 904 Isolation and characterization of cLV25, a Bacteroides fragilis chromosomal transfer factor resembling multiple Bacteroides sp . mobilizable transposons; Bass KA et al.; Horizontal DNA transfer contributes significantly to the dissemination of antibiotic resistance genes in Bacteroides fragilis . To further our understanding of DNA transfer in B . fragilis, we isolated and characterized a new transfer factor, cLV25 . cLV25 was isolated from B . fragilis LV25 by its capture on the nonmobilizable Escherichia coli-Bacteroides shuttle vector pGAT400DeltaBglII . Similar to other Bacteroides sp . transfer factors, cLV25 was mobilized in E . coli by the conjugative plasmid R751 . Using Tn1000 mutagenesis and deletion analysis of cLV25, two mobilization genes, bmgA and bmgB, were identified, whose predicted proteins have similarity to DNA relaxases and mobilization proteins, respectively . In particular, BmgA and BmgB were homologous to MocA and MocB, respectively, the two mobilization proteins of the B . fragilis mobilizable transposon Tn4399 . A cis-acting origin of transfer (oriT) was localized to a 353-bp region that included nearly all of the intergenic region between bmgB and orf22 and overlapped with the 3' end of orf22 . This oriT contained a putative nic site sequence but showed no significant similarity to the oriT regions of other transfer factors, including Tn4399 . Despite the lack of sequence similarity between the oriTs of cLV25 and Tn4399, a mutation in the cLV25 putative DNA relaxase, bmgA, was partially complemented by Tn4399 . In addition to the functional cross-reaction with Tn4399, a second distinguishing feature of cLV25 is that predicted proteins have similarity to proteins encoded not only by Tn4399 but by several Bacteroides sp . transfer factors, including NBU1, NBU2, CTnDOT, Tn4555, and Tn5520. Indian J Med Sci, 2001 Jul, 55(7), 371 - 5 Incidence of anaerobes in throat infections and their sensitivity pattern in Ludhiana; Verma V et al.; Of 175 throat swabs processed, anaerobes were isolated from 16 (9.14%) patients . Isolation of anaerobes from healthy controls was 2 out of 25 (8%) . Peptostreptococci and Bacteroides species were the commonest isolates followed by Peptococci and Propioni-bacterium . All of these isolates were sensitive to Metronidazole . Clindamycin, Erythromycin and Tetracycline also showed good response. Ulus Travma Derg, 2002 Jan, 8(1), 3 - 5 {The effect of antibiotic therapy on lung pathology in experimental models of sepsis}; Mihmanli A et al.; AIMS: In this study, the effect of an extra-lung sepsis model on lung histopathology is evaluated . METHODOLOGY: In this study 20 Wistar-Albino rats were used . Following the ether anesthesia laparotomy was done . Caecum was ligated by a silk thread and was perforated by 18 gauge needle . It is squeezed until feces emerged . Abdominal wall is closed . By this method peritoneal sepsis was performed . The rats are divided into two groups (n:10) . 0.5 ml of serum physiologic is applied to the control group, and imipenem is applied to the antibiotic group as 15 mg/kg/tid . 48 hours later rats were sacrificed by extreme ether anesthesia . Relaparatomy was done and diaphragm was open . Multiple biopsies were made from the lung . Biopsy materials was cultured and examined histopathologically . RESULTS: In control group; rats died in 48 hours (%100), but antibiotic group were alive (%0) . The results of lung biopsy cultures are; in all rats in control group, Escherichia coli (E . coli) and Bacteroides fragilis (B . fragilis) were cultured (%100) . Whereas in antibiotic group there is no bacteria cultured (p < 0.001) . Histopathologic results are: in control group there was wide spread edema and congestion and inflammatory reaction . In antibiotic group there was slight edema, congestion and inflammatory reaction . CONCLUSION: In septic condition sings of adult respiratory distress syndrome occurs . Large spectrum antibiotics can prevent bacterial translocation in lungs and could minimize the lung injury. J Clin Microbiol, 2002 Mar, 40(3), 821 - 5 Association of Bacteroides forsythus and a novel Bacteroides phylotype with periodontitis; Leys EJ et al.; Chronic periodontitis is a common infectious disease in the adult population . The etiology is clearly bacterial, and a small number of bacterial species have been consistently associated with periodontitis, including Bacteroides forsythus and Porphyromonas gingivalis . Comparatively little attention has been paid to the identification of health-associated and potentially beneficial bacterial species that may reside in the gingival sulcus . The purpose of the present study was to examine the relationship of the presence of B . forsythus and a newly identified Bacteroides phylotype, oral clone BU063, to periodontal health status . The study was accomplished with a set of samples that were collected from subjects with periodontitis and healthy controls . These samples had previously been analyzed for the presence of P . gingivalis . An oral sampling strategy that included every tooth and a PCR-based detection method were used to maximize detection sensitivity . The presence of B . forsythus in the oral cavity was strongly associated with periodontitis, and its nearest genetic neighbor, oral clone BU063, was associated with oral health (P < 0.0001 for both) . Colonization with P . gingivalis was independent of the presence of either Bacteroides species, but the two Bacteroides species were found together less often than would be expected by chance (P < 0.0001) . This suggests the presence of a specific exclusionary mechanism between the two Bacteroides species . Comparisons between these two organisms may prove useful for studies that determine how B . forsythus functions in the disease process . In addition, oral clone BU063 deserves further study as a possible preventive or therapeutic intervention for periodontitis. J Vet Pharmacol Ther, 2002 Feb, 25(1), 33 - 8 Pharmacokinetics of ceftiofur in plasma and uterine secretions and tissues after subcutaneous postpartum administration in lactating dairy cows; Okker H et al.; A study was conducted to measure concentrations of potentially active ceftiofur derivatives, in plasma, in uterine tissues (endometrium and caruncles) and in uterine secretions at different time points after a single subcutaneous administration of ceftiofur hydrochloride (Excenel RTU Sterile Suspension) at the dose of 1 mg/kg body weight in Holstein-Friesian dairy cows . The animals (n=4) were injected within 24 h of calving, after expulsion of the foetal membranes . Plasma, lochial fluid, caruncles and endometrium were collected before ceftiofur hydrochloride administration and at 1, 2, 4, 8, 12 and 24 h after treatment . For each cow the concentrations of ceftiofur in the biological matrices were quantified using an high-performance liquid chromatography (HPLC) assay . The limit of quantification of the method was 0.1 microg/mL for plasma and 0.1 microg/g for lochial fluid, caruncles and endometrium . The concentrations of potentially active ceftiofur derivatives detected in plasma reached a maximum of 2.85 +/- 1.11 microg/mL at 2 h and decreased to 0.64 +/- 0.14 microg/mL at 24 h after administration . In lochial fluid, these concentrations reached a maximum of 0.97 +/- 0.25 microg/g at 4 h and decreased to 0.22 +/- 0.21 microg/g at 24 h after administration . In endometrium, these concentrations reached a maximum of 2.23 +/- 0.82 microg/g at 4 h and decreased to 0.56 +/- 0.14 microg/g at 24 h following the injection, whereas these levels in caruncles were 0.96 +/- 0.45 and 0.60 +/- 0.39 microg/g obtained at 8 and 24 h, respectively . At the dose of 1 mg/kg body weight in healthy dairy cows, subcutaneous administration of ceftiofur (as ceftiofur hydrochloride) after parturition results in concentrations of ceftiofur derivatives in uterine tissues and in lochial fluid that exceed the reported minimal inhibitory concentrations (MICs) for the common pathogens (Escherichia coli, Fusobacterium necrophorum, Bacteroides spp., and Arcanobacterium pyogenes) associated with acute puerperal metritis. Gene, 2002 Jan 23, 283(1-2), 95 - 105 Characterization of omp200, a porin gene complex from Bacteroides fragilis: omp121 and omp71, gene sequence, deduced amino acid sequences and predictions of porin structure; Wexler HM et al.; The high MW porin protein complex (Omp200, composed of Omp121 and Omp71) from Bacteroides fragilis ATCC 25285 was purified and tryptic peptide sequences were used to design degenerate oligonucleotide primers which were then used as a first step in amplification, identification and sequencing of the omp121 gene (GenBank Accession Number AF357210) . Sequence analysis revealed an open reading frame of 3378 bases . The deduced amino acid sequence (which contained the experimentally determined peptide sequences) has 1125 or 1116 amino acids (depending on which start codon is used); the mature protein consists of 1096 amino acids, has a predicted MW of 121.4 and a theoretical pI of 6.32 . It is preceded by a 29 or 18 amino acid signal peptide which includes a typical hydrophobic region near the N-terminus (VLVLVL) . Hydropathy plots of the deduced amino acid sequence of B . fragilis Omp121 display striking similarity with those of Escherichia coli OmpC (a 16-stranded porin) and FepA (a 22-stranded ligand-gated transport protein) . Three-dimensional modeling of B . fragilis Omp121 (based on 1D and 3D sequence profiles, coupled with secondary structure and solvation potential information) indicated that the closest homologues in terms in fold conservation were the E . coli 16-stranded porins (e.g . OsmA) and 22-stranded ligand gated transport proteins (e.g . FepA) . The omp71 gene sequence was identified using the tryptic peptides to search the published Bacteroides genome data base . We found that omp71 is located immediately downstream of omp121 and confirmed this with PCR analysis . Omp71 has no known homologues but does share some characteristics with the Porphyromonas RagB antigen. Clin Microbiol Infect, 1996, 2(2), 115 - 122 Evaluation of the Rapid ID 32A system for the identification of the Bacteroides fragilis group; King A et al.; OBJECTIVE: To evaluate the use of a rapid identification system, Rapid ID 32A (bioMerieux), for the identification of clinically important species in the B . fragilis group . METHODS: The use of Rapid ID 32A was validated on 249 clinical isolates, all of which were tested by conventional techniques, and in selected instances API 20A . Rapid ID 32A (and API 20A as appropriate) was then applied in a central laboratory to the identification of 1289 B . fragilis group clinical isolates from 22 laboratories in 15 European countries . RESULTS: Improvements in the initial database permitted the accurate identification of isolates of B . fragilis, B . thetaiotaomicron and B . vulgatus, but further tests, especially for catalase production, were required to distinguish between B . ovatus and B . uniformis, while an identification of B . distasonis could be accepted only after careful review of results . There were too few isolates of B . caccae, B . merdae and B . stercoris for us to reach satisfactory conclusions, but further tests are clearly necessary . CONCLUSIONS: The study emphasizes the importance of including sufficient numbers of isolates of different species in the validation of identification methods . Rapid ID 32A is a reliable system for the identification of the common species in the B . fragilis group, especially B . fragilis and B . thetaiotaomicron. Clin Microbiol Infect, 1995 Sep, 1(1), 44 - 47 Endocarditis Caused by Multiply Resistant Bacteroides fragilis: Case Report and Review; Lortholary O et al.; A 78-year-old woman developed fatal endocarditis of her prosthetic aortic valve, caused by Bacteroides fragilis fragilis, and associated with ovarian carcinoma . The strain showed multiple antibiotic resistance, including resistance to beta-lactam agents and combinations with beta-lactamase inhibitors . Seventeen previously described cases of endocarditis caused by Bacteroides spp . have been found in the literature . The mean age of the 18 patients was 50.3 years, the gastro-intestinal tract was the most common site of associated disease, embolism occured in ten cases and eight patients died . Previous isolates showed the antibiotic susceptibility customarily associated with the B . fragilis group. Biosci Biotechnol Biochem, 2002 Jan, 66(1), 78 - 84 Diverse bacteria related to the bacteroides subgroup of the CFB phylum within the gut symbiotic communities of various termites; Ohkuma M et al.; Phylogenetically diverse clones of the partial 16S rDNA (ca . 850 bp) of bacteria belonging to the bacteroides subgroup of the cytophaga-flavobacter-bacteroides phylum were collected from the symbiotic microbial communities in the guts of six termite species without cultivation . Combined with the sequences reported previously, a total of thirty phylotypes of the subgroup were identified and classified into five phylogenetic clusters . One that was comprised of the phylotypes from a single termite species was related to the genus Rikenella . Two were clustered each with some cultured strains, genera of which have not been clearly defined yet . The remaining two clusters had no culturable representatives, suggesting the presence of yet-uncultivated genera within the termite guts . From these sequence data, we designed a specific primer for the bacteroides subgroup, which was successful in the terminal-restriction fragment length polymorphism analysis to detect the phylotypes of the subgroup in the termite gut. Clin Microbiol Infect, 1997 Feb, 3(1), 82 - 88 Postantibiotic effects with Bacteroides fragilis determined by viable counts and CO2 generation; Valdimarsdottir M et al.; OBJECTIVE: To study the postantibiotic effect (PAE) for Bacteroides fragilis after exposure to common anaerobic antimicrobials with two different methods, by viable counting and by measuring CO2 generation in a BACTEC(R) blood culture system . METHODS: Four strains of B . fragilis were exposed for 1, 2 and 4 h to cefoxitin, chloramphenicol, clindamycin, imipenem or metronidazole at concentrations from 1 to 16 x MIC . The drugs were removed by dilution into BACTEC 7A(R) vials and growth determined with viability counts and CO2 production . RESULTS: The durations of the PAEs determined by the two methods correlated well (r=0.913, p<0.005) . PAEs of up to 4-5 h were induced by imipenem and metronidazole with achievable concentrations and exposure durations . Chloramphenicol induced short or no PAEs, but cefoxitin and clindamycin induced PAEs up to 2 h with high AUC values . The imipenem PAEs and the short cefoxitin and clindamycin PAEs were dependent on AUC . CONCLUSIONS: Significant PAEs against B . fragilis were induced by imipenem and metronidazole . Determining PAE by measuring CO2 production is an accurate and less time-consuming alternative to the conventional method of viable counts. J Med Microbiol, 2002 Feb, 51(2), 123 - 30 RecA and glnA sequences separate the bacteroides fragilis population into two genetic divisions associated with the antibiotic resistance genotypes cepA and cfiA; Gutacker M et al.; The sequences of part of the glutamine synthetase-encoding gene (glnA) and of the RecA-encoding gene (recA) were determined and aligned for 45 Bacteroides fragilis isolates from different clinical and geographical origin . The patterns of sequence divergence of glnA and recA were very similar . The sequences of a 303-bp fraction of recA showed 45 nucleotide substitutions, 40 of which allowed the separation of B . fragilis into two major divisions, which were not found when the deduced amino acid sequences were considered . The 687-bp sequences analysed for the glnA gene showed 112 nucleotide substitutions, 96 of which separated the population into the same two divisions as those described for recA . In this case, the deduced amino acid sequences showed this subdivision as well: three of the six observed amino acid substitutions were division-specific . Within the two divisions, both genes presented a high degree of sequence conservation . Each B . fragilis division was associated with the presence of a different antibiotic resistance gene: cepA encoding a serine-beta-lactamase (division I) and cfiA encoding a metallo-beta-lactamase (division II) . No particular clusters associated with geographical or clinical origin, or with the production of an enterotoxin were observed . Sequencing of the cfiA gene allowed identification of two different alleles in division II . However, no association of these different cfiA alleles with the expression of imipenem resistance was observed . In conclusion, the phylogenetic patterns observed by sequencing recA and glnA are in agreement with those obtained previously by MLEE (multilocus enzyme electrophoresis) . Thus, it appears that the evolution of recA and glnA genes is similar to that of the whole chromosome of B . fragilis . Horizontal gene transfer between divisions I and II seems to be low, at best . However, the results of the present study could not clarify definitively whether divisions I and II should be considered as two different B . fragilis genospecies. Oral Microbiol Immunol, 2002 Feb, 17(1), 55 - 9 Periodontal pathogen detection in gingiva/tooth and tongue flora samples from 18- to 48-month-old children and periodontal status of their mothers; Yang EY et al.; Few studies have detected periodontal pathogens in young children, and when detected the prevalence has been relatively low . In this epidemiological study, we determined the prevalence of periodontal pathogen colonization in young children and examined the relationship between periodontitis in mothers and detection of periodontal pathogens in their children aged 18-48 months . Children were selected and enrolled randomly into the study; tongue and gingival/tooth plaque samples were harvested and analyzed by DNA probe checkerboard assay for Porphyromonas gingivalis and Bacteroides forsythus . Clinical measurements included a gingival bleeding score in the children and a periodontal screening and recording (PSR) score in the mothers . Mothers having one or more periodontal sites with probing depths > 5.5 mm were classified as having periodontitis . In this population, 71% (66/93) of the 18- to 48-month-old children were infected with at least one periodontal pathogen . Detection rates for children were 68.8% for P . gingivalis and 29.0% for B . forsythus . About 13.8% (11/80) of children had gingival bleeding in response to a toothpick inserted interproximally . Children in whom B . forsythus was detected were about 6 times more likely to have gingival bleeding than other children . There was no relationship between bleeding and detection of P . gingivalis . 17.0% (16/94) of the mothers had periodontitis . When all mother-child pairs were considered, the periodontal status of the mother was found not to be a determinant for detection of periodontal pathogens in the floral samples from the children . However, the odds ratio that a daughter of a mother with periodontitis would be colonized was 5.2 for B . forsythus . A much higher proportion of children in this population were colonized by P . gingivalis and/or B . forsythus than has been previously reported for other populations . A modest level of association between manifestations of periodontitis in mothers and detection of B . forsythus in their daughters was observed. J Periodontal Res, 2002 Feb, 37(1), 75 - 8 Dialister pneumosintes, a new putative periodontal pathogen; Ghayoumi N et al.; Recent studies have implicated Dialister pneumosintes as a candidate periodontal pathogen . This study determined the association of subgingival D . pneumosintes with demographic variables (age and gender) and the presence of subgingival periodontopathic Bacteroides forsythus and Porphyromonas gingivalis . Microbial identification by established PCR techniques was performed in samples from 149 periodontitis patients . Subgingival D . pneumosintes occurred with significantly higher prevalence in older individuals and was closely associated with subgingival B . forsythus . D . pneumosintes may play an important role in the microbial complex responsible for destructive periodontal disease. Curr Issues Mol Biol, 2002 Jan, 4(1), 13 - 8 Analysis of specific bacteria from environmental samples using a quantitative polymerase chain reaction; Brunk CF et al.; This article describes the use of quantitative PCR for measuring bacterial abundance in environmental samples . The two approaches discussed are: 1) The use of an internal PCR standard constructed to be the same size and have the same sequence as the primary amplification target, but differing from the primary target by 2-3 bases, corresponding to a unique restriction site . This allows the amount of target amplicon to be compared with the internal standard and circumvents the problem of differential amplification efficiencies when using dissimilar targets and standard amplicons . 2) The use of Taqman technology (Applied Biosystems, Foster City, California) with a dual labeled oligonucleotide probe which binds internal to the PCR primers . The detection of Bacteroides is used as an example for both approaches. J Endod, 2002 Feb, 28(2), 90 - 3 Stimulation of matrix metalloproteinases by black-pigmented Bacteroides in human pulp and periodontal ligament cell cultures; Chang YC et al.; Matrix metalloproteinases (MMPs) are a group of proteolytic enzymes capable of degrading most components of the extracellular matrix . Recently, evidence has shown that MMPs may play a role in tissue degradation in inflamed dental pulp . To date very little is known regarding the mechanism of extracellular matrix destruction at the site of bacterial infection . The purpose of this study was to determine the effects of the supernatants from Porphyromonas endodontalis and Porphyromonas gingivalis on the production and secretion of MMPs by primary human pulp and periodontal ligament (PDL) cell cultures in vitro . The results were evaluated by substrate gel zymography from long-term cultures . The main gelatinase secreted by human pulp and PDL cells migrated at 72 kDa and represented MMP-2 . Minor gelatinolytic bands were also observed at 92 kDa regions that correspond to MMP-9 . After an 8-day culture period, P . endodontalis and P . gingivalis were found to elevate MMP-2 production both in human pulp and PDL cell cultures . In addition, the stimulation was in a dose- and time-dependent manner . Both human pulp and PDL cells, however, treated with either P . endodontalis or P . gingivalis had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions . These results indicate that black-pigmented Bacteroides species play an important role in tissue destruction and disintegration of extracellular matrix in pulpal and periapical diseases . Thus, activation of MMPs may be one of the distinct host degradative pathways in the pathogenesis of microbial-induced pulpal and periapical lesion . An understanding of the actions of these black-pigmented Bacteroides species on pulp and PDL cells may result in new therapies to augment current treatment of pulpal and periapical lesions. Risk Anal, 2001 Dec, 21(6), 1097 - 108 Modeling virus inactivation on salad crops using microbial count data; Petterson SR et al.; Microbial counts of the persistent Bacteroides fragilis bacteriophage B40-8 from a virus decay experiment conducted under glasshouse conditions were used to model the decay of viruses on wastewater-irrigated lettuce and carrot crops . The modeling approach applied gave specific consideration to the discrete nature of microbial count data . The experimental counts were best fit by a negative binomial distribution indicating highly dispersed distribution of viruses on lettuce and carrot crops following irrigation with wastewater . In addition, there was evidence for biphasic inactivation of viruses, signifying the presence of a persistent subpopulation of viruses that decayed slowly, resulting in virus accumulation on the crop surface over subsequent irrigations . Maximum likelihood estimates of initial and persistent subpopulation inactivation rates were 2.48 day(-1) and 0.51 day(-1) for lettuces and 0.84 day(-1) and 0.046 day(-1) for carrots . Maximum likelihood estimates of the persistent virus subpopulation size were 0.12% and 2% for lettuce and carrots, respectively. Appl Environ Microbiol, 2002 Feb, 68(2), 673 - 90 Culture-independent analysis of gut bacteria: the pig gastrointestinal tract microbiota revisited; Leser TD et al.; The phylogenetic diversity of the intestinal bacterial community in pigs was studied by comparative 16S ribosomal DNA (rDNA) sequence analysis . Samples were collected from a total of 24 pigs representing a variety of diets, ages, and herd health status . A library comprising 4,270 cloned 16S rDNA sequences obtained directly by PCR from 52 samples of either the ileum, the cecum, or the colon was constructed . In total, 375 phylotypes were identified using a 97% similarity criterion . Three hundred nine of the phylotypes (83%) had a <97% sequence similarity to any sequences in the database and may represent yet-uncharacterized bacterial genera or species . The phylotypes were affiliated with 13 major phylogenetic lineages . Three hundred four phylotypes (81%) belonged to the low-G+C gram-positive division, and 42 phylotypes (11.2%) were affiliated with the Bacteroides and Prevotella group . Four clusters of phylotypes branching off deeply within the low-G+C gram-positive bacteria and one in the Mycoplasma without any cultured representatives were found . The coverage of all the samples was 97.2% . The relative abundance of the clones approximated a lognormal distribution; however, the phylotypes detected and their abundance varied between two libraries from the same sample . The results document that the intestinal microbial community is very complex and that the majority of the bacterial species colonizing the gastrointestinal tract in pigs have not been characterized. Appl Environ Microbiol, 2002 Feb, 68(2), 505 - 18 Phylogenetic composition of bacterioplankton assemblages from the Arctic Ocean; Bano N et al.; We analyzed the phylogenetic composition of bacterioplankton assemblages in 11 Arctic Ocean samples collected over three seasons (winter-spring 1995, summer 1996, and summer-fall 1997) by sequencing cloned fragments of 16S rRNA genes . The sequencing effort was directed by denaturing gradient gel electrophoresis (DGGE) screening of samples and the clone libraries . Sequences of 88 clones fell into seven major lineages of the domain Bacteria: alpha(36%)-, gamma(32%)-, delta(14%)-, and epsilon(1%)-Proteobacteria; Cytophaga-Flexibacter-Bacteroides spp . (9%); Verrucomicrobium spp . (6%); and green nonsulfur bacteria (2%) . A total of 34% of the cloned sequences (excluding clones in the SAR11 and Roseobacter groups) had sequence similarities that were <94% compared to previously reported sequences, indicating the presence of novel sequences . DGGE fingerprints of the selected samples showed that most of the bands were common to all samples in all three seasons . However, additional bands representing sequences related to Cytophaga and Polaribacter species were found in samples collected during the summer and fall . Of the clones in a library generated from one sample collected in spring of 1995, 50% were the same and were most closely affiliated (99% similarity) with Alteromonas macleodii, while 50% of the clones in another sample were most closely affiliated (90 to 96% similarity) with Oceanospirillum sp . The majority of the cloned sequences were most closely related to uncultured, environmental sequences . Prominent among these were members of the SAR11 group . Differences between mixed-layer and halocline samples were apparent in DGGE fingerprints and clone libraries . Sequences related to alpha-Proteobacteria (dominated by SAR11) were abundant (52%) in samples from the mixed layer, while sequences related to gamma-proteobacteria were more abundant (44%) in halocline samples . Two bands corresponding to sequences related to SAR307 (common in deep water) and the high-G+C gram-positive bacteria were characteristic of the halocline samples. Medicina (B Aires), 2001, 61(6), 855 - 9 {Septic thrombophlebitis of the portal vein associated with reversible portal hypertension}; Gnocchi CA et al.; Septic thrombophlebitis of the portal vein is an unusual and serious complication of abdominal infection . We present a patient with thrombophlebitis of the portal vein of unknown origin, suffering from fever, abdominal pain, jaundice, abnormal liver test function and bacteremia related to Bacteroides fragilis . Ultrasonography, with doppler of the portal vein, was performed which showed thrombosis of the portal vein together with signs of portal hypertension . The patient underwent six weeks of antibiotic treatment . The evolution was favourable, the infection was overcome and the portal vein was de-obstructed as a consequence of which the signs of portal hypertension disappeared. J Bacteriol, 2002 Feb, 184(4), 895 - 903 Aerobic-type ribonucleotide reductase in the anaerobe Bacteroides fragilis; Smalley D et al.; Bacteroides fragilis, a component of the normal intestinal flora, is an obligate anaerobe capable of long-term survival in the presence of air . Survival is attributed to an elaborate oxidative stress response that controls the induction of more than 28 peptides, but there is limited knowledge concerning the identities of these peptides . In this report, RNA fingerprinting by arbitrarily primed PCR identified five new genes whose expression increased following exposure to O2 . Nucleotide sequence analysis of the cloned genes indicated that they encoded an outer membrane protein, an aspartate decarboxylase, an efflux pump, heat shock protein HtpG, and an NrdA ortholog constituting the large subunit of a class Ia ribonucleotide reductase (RRase) . Attention was focused on the nrdA gene since class I RRases are obligate aerobic enzymes catalyzing the reduction of ribonucleoside 5'-diphosphates by a mechanism that requires molecular oxygen for activity . Sequence analysis of the nrd locus showed that two genes, nrdA and nrdB, are located in the same orientation in a 4.5-kb region . Northern hybridization and primer extension experiments confirmed induction of the genes by O2 and suggested they are an operon . The B . fragilis nrdA and nrdB genes were overexpressed in Escherichia coli, and CDP reductase assays confirmed that they encoded an active enzyme . The enzyme activity was inhibited by hydroxyurea, and ATP was shown to be a positive effector of CDP reductase activity, while dATP was an inhibitor, indicating that the enzyme was a class Ia RRase . A nrdA mutant was viable under anaerobic conditions but had decreased survival following exposure to O2, and it could not rapidly resume growth after O2 treatment . The results presented indicate that during aerobic conditions B . fragilis NrdAB may have a role in maintaining deoxyribonucleotide pools for DNA repair and growth recovery. J Bacteriol, 2002 Feb, 184(3), 728 - 38 Isolation and characterization of BTF-37: chromosomal DNA captured from Bacteroides fragilis that confers self-transferability and expresses a pilus-like structure in Bacteroides spp . and Escherichia coli; Vedantam G et al.; We report the isolation and preliminary characterization of BTF-37, a new 52-kb transfer factor isolated from Bacteroides fragilis clinical isolate LV23 . BTF-37 was obtained by the capture of new DNA in the nonmobilizable Bacteroides-Escherichia coli shuttle vector pGAT400DeltaBglII using a functional assay . BTF-37 is self-transferable within and from Bacteroides and also self-transfers in E . coli . Partial DNA sequencing, colony hybridization, and PCR revealed the presence of Tet element-specific sequences in BTF-37 . In addition, Tn5520, a small mobilizable transposon that we described previously (G . Vedantam, T . J . Novicki, and D . W . Hecht, J . Bacteriol . 181:2564-2571, 1999), was also coisolated within BTF-37 . Scanning and transmission electron microscopy of Tet element-containing Bacteroides spp . and BTF-37-harboring Bacteroides and E . coli strains revealed the presence of pilus-like cell surface structures . These structures were visualized in Bacteroides spp . only when BTF-37 and Tet element strains were induced with subinhibitory concentrations of tetracycline and resembled those encoded by E . coli broad-host-range plasmids . We conclude that we have captured a new, self-transferable transfer factor from B . fragilis LV23 and that this new factor encodes a tetracycline-inducible Bacteroides sp . conjugation apparatus. Med Dosw Mikrobiol, 2001, 53(3), 259 - 67 {Adhesion of human granulocytes and T lymphocytes to vascular endothelial cells after stimulation with Bacteroides fragilis endotoxin and enterotoxin}; Rokosz A et al.; The aim of presented study was to estimates the number of human granulocytes and T lymphocytes adhering to 1 mm2 of vascular endothelial cell culture stimulated by Bacteroides fragilis endotoxins (LPS) and enterotoxin (BFT) . HMEC-1 cells were activated with bacterial preparations at the concentration of 10 (micrograms/ml for 4 and 24 hours . Granulocytes and T lymphocytes were isolated from peripheral blood of healthy blood donors . The adhesion tests of granulocytes and adhesion tests of resting and activated with PMA (at the concentration of 10 ng/ml) T lymphocytes to the non-stimulated and stimulated by B . fragilis compounds (LPS and BFT) vascular endothelium were performed . The number of viable leukocytes, which adhered to the endothelium, was determined using inverted microscope (magnification 200x) . The results were presented as the number of viable cells adhering to 1 mm2 of the endothelial cell culture . The results of experiments indicate that granulocytes and T lymphocytes (resting and after activation with PMA even in greater number) adhere to the endothelial cells stimulated by B . fragilis endotoxins and enterotoxin . B . fragilis toxins are weaker stimulants of human leukocyte adhesion to the HMEC-1 cells than E . coli O55:B5 LPS . B . fragilis LPS and BFT preparations stimulate endothelial cells to the adhesion of granulocytes in similar manner, whereas the activation of vascular endothelium to the adhesion of T lymphocytes is differentiated. Clin Diagn Lab Immunol, 2002 Jan, 9(1), 54 - 9 Bacteroides ovatus as the predominant commensal intestinal microbe causing a systemic antibody response in inflammatory bowel disease; Saitoh S et al.; To clarify what bacterial species of commensal intestinal microbes are recognized as the antigens that induce a serum antibody response in patients with inflammatory bowel disease (IBD), 72 subjects consisting of 12 Crohn's disease patients, 30 ulcerative colitis patients, and 30 healthy volunteers were examined for their titers of serum antibody to these intestinal bacteria . In IBD patients, as a result, significant elevations of both the immunoglobulin G (IgG) and IgA titers to Bacteroides ovatus were found . Immunoblotting showed that a definite 19.5-kDa band of B . ovatus was bound to the serum antibody raised in IBD patients . It was thus concluded that B . ovatus causes serum antibody responses in IBD patients, and a 19.5-kDa molecule of this bacterium appears to be the responsible antigen, although the role of this event in pathogenesis remains unclear. Vet Res, 2001 Nov-Dec, 32(6), 611 - 6 Possible misidentification of Bacteroides sp., probably B . ureolyticus as Taylorella equigenitalis: implications for the laboratory diagnosis of CEM; Moore JE et al.; A wild-type isolate with similar morphological and phenotypic properties to Taylorella equigenitalis, the causative bacterial agent of contagious equine metritis (CEM), was referred for molecular identification by PCR amplification of the 16S rRNA gene . A species-specific PCR failed to yield a product compatible with that of T . equigenitalis . The direct sequencing of the universal 16S rRNA PCR amplicon suggested the presence of a Bacteroides sp., probably Bacteroides ureolyticus, with no consequent effects on the movement and transportation of the animal . Adoption of such a molecular means of identification through sequencing may aid in the identification of the atypical forms of Taylorella equigenitalis, as recently described, as well as differentiating this species from Taylorella asinigenitalis. J Periodontal Res, 2001 Dec, 36(6), 398 - 403 Bacteroides forsythus prtH genotype in periodontitis patients: occurrence and association with periodontal disease; Tan KS et al.; Bacteroides forsythus has been described as a periodontopathogen and its presence in the subgingival plaque can lead to periodontal disease . Recently, a cysteine protease designated as prtH was isolated and characterized from B . forsythus ATCC 43037 . The purpose of this study was to determine the prevalence and the association of the prtH gene of B . forsythus with periodontal disease . A total of 160 subgingival plaque samples were assayed with the polymerase chain reaction method using oligonucleotide primers targeting the prtH and the 16S rDNA genes of B . forsythus . Primers targeting the 16S rDNA gene of B . forsythus were used to determine the occurrence of the bacteria in the subgingival plaque samples at baseline . At baseline, B . forsythus was detected in 78 out of 86 (91%) diseased sites and 33 out of 74 (45%) healthy sites studied . Among the 86 diseased sites examined, 73 sites (85%) were colonized by the bacteria with the prtH genotype . In sites of the periodontally healthy, 7 out of 73 (10%) possessed B . forsythus with the prtH genotype . The results obtained suggested strong association of the prtH gene of B . forsythus with adult periodontitis . Although this bacterial species was detected from about half of the periodontally healthy samples, only a fraction of these subjects possess the bacteria strain with the prtH genetic subtype . We propose the use of the prtH gene as an alternative to the more widely used 16S rDNA gene of B . forsythus, for a more accurate determination of the prevalence of periodontal health and disease in epidemiological studies and clinical screening. J Chemother, 2001 Oct, 13(5), 510 - 8 Influence of in-vivo endotoxin liberation on anti-anaerobic antimicrobial efficacy; Rotimi VO et al.; The ability of cefoxitin, clindamycin, imipenem, meropenem, metronidazole and piperacillin-tazobactam to cause gram-negative anaerobic bacteria to release endotoxin and the influence of such liberated endotoxin on antibiotic efficacy were investigated in in-vivo experiments in animal models . Experimental infections in various animal models (mice, hamster and infant rats) with cultures of wild and reference strains of Bacteroides fragilis group and Fusobacterium spp . were carried out by injecting these animals with different inocula (10(6), 10(7) and 10(8) cfu/ml) of the bacterial suspension, Appropriate doses of the test antibiotics were then injected and the plasma lipopolysaccharide (endotoxin) release measured by the Limulus Amoebocyte Lysate (LAL) Assay . Evidence of worsening of the outcome of the infections post-therapy was assessed, including histopathological changes in the internal organs . Infection with generalized septicemia was established with F . nucleatum in the mice and hamster models while with the B . fragilis group, infections only led to intra-abdominal abscess formation . Plasma endotoxin release was higher in animals infected with F . nucleatum than B . fragilis and was unrelated to the bacterial inoculum . Imipenem, meropenem and cefoxitin, in that order, induced the highest levels of endotoxin activities in the animal model, particularly following F . nucleatum infection . Histological examination of the internal organs of various animals showed variation in the pattern of histopathological changes; grades 3-4 inflammatory changes in the liver were observed in the Fusobacterium-infected animals that were treated with the carbapenems and cefoxitin . Therapy with the other antibiotics did not exacerbate anaerobic sepsis . In this study, bacteremia did not lead to massive endotoxin release and antibiotic therapy appeared not to have negatively influenced the outcome of most of the gram-negative anaerobic infections, except for infections caused by Fusobacterium spp . However, it is conceivable that if the gastrointestinal tract is the source of the endotoxin in patients with systemic inflammatory response syndrome, then the obligate anaerobes like Bacteroides and Fusobacterium species, which are members of the gut flora, may play a major role in the unfavorable outcome of antibiotic therapy in some of these infections. Med Dosw Mikrobiol, 2001, 53(2), 177 - 83 {Analysis of fatty acids from lipopolysaccharides of Bacteroides thetaiotaomicron and Bacteroides fragilis}; Rokosz A et al.; The aim of this study was to determine and to compare fatty acids occurring in lipopolysaccharides (LPS) isolated from B . thetaiotaomicron and B . fragilis strains of different origin . Lipopolysaccharides of three B . thetaiotaomicron strains and four B . fragilis strains were isolated by phenol-water extraction according to the procedure of Westphal and Jann (1965) . Water-phase LPS fractions were then treated with nucleases and purified by ultracentrifugation as described by Gmeiner (1975) . Fatty acid methyl esters, obtained by methanolysis of LPS, were analysed in gas-liquid chromatography combined with mass spectrometry (GLC-MS) . Trimethylsilylated hydroxyl groups of fatty acid methyl esters were identified with GLC-MS using a method of selective ion monitoring (SIM) . Lipopolysaccharides of B . thetaiotaomicron and B . fragilis strains contained long-chain (15-18 carbon atoms) fatty acids . The broad spectrum of simple long-chain and branched-chain fatty acids as well as 3-hydroxy fatty acids were detected . The main fatty acid of analyzed bacterial species was 3-hydroxy-hexadecanoic acid (3OH C16:0) . Several 3-hydroxy fatty acids were detected in LPS of examined strains . Fatty acids occurring in LPS of B . thetaiotaomicron and B . fragilis strains appeared to be qualitatively similar . Quantitative differences in fatty acids composition of lipopolysaccharides isolated from strains of different origin were observed. Med Dosw Mikrobiol, 2001, 53(2), 161 - 6 {Enterotoxin-producing Bacteroides fragilis strains isolated from horses}; Obuch-Woszczatynski P et al.; Seven Bacteroides fragilis strains were cultured from samples collected from horses . From all the tested strains, as well as from the reference B . fragilis strains: enterotoxigenic NCTC 11925 and nonenterotoxigenic IPL 323 strain, DNA was isolated using Genomic DNA PREP PLUS isolation kit manufactured by A&A Biotechnology (Poland) . To detect the enterotoxin (fragilysin) gene, polymerase chain reaction (PCR) was applied, using the following starters: 404 (GAG CCG AAG ACG GTG TAT GTG ATT TGT) and 407 (TGC TCA GCG CCC AGT ATA TGA CCT AGT) . DNA obtained from bacterial cells was amplified in a thermocycler (Techne) . The temperature profile was as follows: 1 cycle (4 min . 94 degrees C), 40 cycles (1 min . 94 degrees C, 1 min . 52 degrees C, 1 min . 74 degrees C) . Amplification products were detected by electrophoresis in agarose gel (1%) with ethidium bromide added . The presence of the fragilysin gene was detected in two strains . Among the strains isolated from horses enterotoxin gene-possessing Bacteroides fragilis strains (ETBF) can be detected. Med Dosw Mikrobiol, 2001, 53(2), 151 - 60 {Effect of clindamycin on stimulation of cell adhesion molecules by endotoxins and enterotoxin of Bacteroides fragilis strains}; Meisel-Mikolajczyk F et al.; The influence of clindamycin on expression of B . fragilis endotoxins (LPS) and enterotoxin stimulated cell adhesion molecules: ICAM-1, VCAM-1 and E-selectin on HMEC-1 (human microvascular endothelial cell line) was tested . Lipopolysaccharides from four Bacteroides fragilis strains: one nonenterotoxigenic (NTBF) and three enterotoxigenic (ETBF) were extracted by hot phenol-water method and purified . B . fragilis enterotoxin was prepared according to the method described by van Tassel et al . (1992) . All bacterial preparations were used for stimulation at concentration 10 micrograms/ml . Clindamycin was used in concentration of 2 micrograms/ml . The influence of antimicrobial agent on the endotoxins and enterotoxin stimulation and expression of adhesion molecules was tested by ELISA, using monoclonal mouse anti-human antibodies (Genzyme, USA) . Peroxidase-conjugated rabbit anti-mouse immunoglobulins (DAKO A/S Denmark) and OPD (Sigma USA) were used . The coloured reaction product was measured by reading the absorbance at 492 nm in SPECTRA II reader (SLT, Austria) . It was observed that clindamycin influenced the expression of cell adhesion molecules on resting cell line . HMEC-1 cells stimulated with Bacteroides fragilis LPS preparations have suppressive effect on ICAM-1 expression . ICAM-1 expression was augmented when stimulated with Tox 1 and Tox 2 preparations . Clindamycin augmented the VCAM-1 expression in tests with all bacterial preparations . All used bacterial preparations of Bacteroides fragilis LPS and enterotoxin enhanced the expression of E-selectin with exception of LPS of NTBF strain. Med Dosw Mikrobiol, 2001, 53(1), 53 - 61 {The effect of metronidazole on stimulation of adhesion molecule expression on the surface of vascular endothelial cells by Bacteroides fragilis endotoxins and enterotoxin}; Meisel-Mikolajczyk F et al.; The influence of metronidazole on the level of expression of adhesion molecules ICAM-1, VCAM-1 and E-selectin on the surface of vascular endothelial cells activated with B . fragilis endotoxins and enterotoxin was examined . Three enterotoxigenic (ETBF) strains and one nonenterotoxigenic (NTBF) strain were used for lipopolysaccharide extraction . Enterotoxin was prepared from the culture supernatant of the reference B . fragilis ATCC 43858 strain . Expression of adhesion molecules on vascular endothelial cells (HMEC-1 cell line) was determined after their stimulation with bacterial compounds at the concentration of 10 micrograms/ml in the presence of metronidazole at the concentration of 4 micrograms/ml . Endothelial cells were activated for 4 hours (E-selectin expression) and for 24 hours (ICAM-1 and VCAM-1 expression) . Adhesion molecules were detected in immunoenzymatic test (ELISA) with mouse, monoclonal antibodies against human ICAM-1, VCAM-1 and E-selectin . The results of experiments suggest, that metronidazole enhances the expression of examined adhesion molecules on endothelial cells . This antimicrobial agent causes some changes in the expression of endothelial ICAM-1, VCAM-1 and E-selectin stimulated by B . fragilis endotoxins and enterotoxin. Antimicrob Agents Chemother, 2002 Jan, 46(1), 203 - 10 Pharmacodynamics of trovafloxacin and levofloxacin against Bacteroides fragilis in an in vitro pharmacodynamic model; Peterson ML et al.; An in vitro pharmacodynamic investigation was conducted to explore whether the area under the concentration time curve from 0 to 24 h (AUC(0-24))/MIC ratio could predict fluoroquinolone performance against Bacteroides fragilis . An in vitro model was used to generate kill curves for trovafloxacin (TVA) and levofloxacin (LVX) at AUC(0-24)/MIC ratios of 1 to 406 against three strains of B . fragilis (ATCC 25285, ATCC 23745, and clinical isolate M97-117) . TVA and LVX were bolused prior to the start of experiments to achieve the corresponding AUC(0-24)/MIC ratio . Experiments were performed in duplicate over 24 h and in an anaerobic environment . Analyses of antimicrobial performance were conducted by comparing the rates of bacterial kill (K) using nonlinear regression analysis with 95% confidence intervals . Statistical significance was defined as a lack of overlap in the 95% confidence limits generated from the slope of each kill curve . For both TVA and LVX, K was maximized once an AUC(0-24)/MIC ratio of > or =40 was achieved and was not further increased despite a 10-fold increase in AUC(0-24)/MIC from approximately 40 to 400 against all three strains of B . fragilis . No significant differences were found in K between AUC(0-24)/MIC ratios of approximately 40 to 200 . In experiments where AUC(0-24)/MIC ratios that were > or = 5 and < or = 44 were conducted, 64% demonstrated regrowth at 24 h . Resistant strains were selected in 50% of those experiments, demonstrating regrowth, which resulted in increased MICs of two- to 16-fold for both TVA and LVX . Regrowth did not occur, nor were resistant strains selected in any studies with an AUC/MIC that was > 44 . Our findings suggest that fluoroquinolones provide antibacterial effects against B . fragilis in a concentration-independent manner associated with an AUC(0-24)/MIC ratio of > or =40 . Also, the potential for the selection of resistant strains of B . fragilis may increase with an AUC(0-24)/MIC ratio of < or =44. Infect Immun, 2002 Jan, 70(1), 5 - 10 Escherichia coli hemoglobin protease autotransporter contributes to synergistic abscess formation and heme-dependent growth of Bacteroides fragilis; Otto BR et al.; Intra-abdominal infections (IAI) continue to be a serious clinical problem . Bacterial synergism is an important factor that influences the shift from contamination to IAI, leading to the development of lesions and abscess formation . Escherichia coli and Bacteroides fragilis are particularly abundant in IAI . The underlying molecular mechanisms of this pathogenic synergy are still unclear . The role of the hemoglobin protease (Hbp) autotransporter protein from E . coli in the synergy of IAI was investigated . Hbp is identical to Tsh, a temperature-sensitive hemagglutinin associated with avian pathogenic E . coli . Clinical isolates from miscellaneous extraintestinal infections were phenotypically and genotypically screened for Hbp . The presence of Hbp was significantly associated with E . coli isolated from IAI and other extraintestinal infections . In a murine infection model, Hbp was shown to contribute to the pathogenic synergy of abscess development . Mice immunized with Hbp were protected against mixed infections and did not develop abscess lesions . Furthermore, an E . coli wild-type strain that did not induce abscess formation in the synergy model was transformed with a plasmid encoding the hbp gene, and mixed infections with this strain lead to increased growth of B . fragilis and induction of abscess lesions . Growth-promoting studies showed that purified Hbp is able to deliver heme to B . fragilis strain BE1 . In conclusion, results suggest the synergy of abscess formation by E . coli and B . fragilis can be partly explained by the capacity of B . fragilis to intercept Hbp and iron from heme to overcome the iron restrictions imposed by the host. Oral Microbiol Immunol, 2001 Dec, 16(6), 376 - 82 Supragingival and subgingival microbiota of adult patients with Down's syndrome . Changes after periodontal treatment; Sakellari D et al.; In this longitudinal study, five adult Down's syndrome patients with periodontitis were placed on a frequent recall visit schedule (every 6 weeks) after treatment, in order to investigate: 1) the microbiological status, both supragingivally and subgingivally, and the changes that occurred after treatment and 2) the effect of frequent professional supragingival plaque control on the subgingival microbiota and clinical variables in these patients . The clinical variables recorded were probing pocket depth, probing attachment level, bleeding on probing and presence of plaque (full mouth, six surfaces per tooth) . Microbiological examination was performed separately for supragingival and subgingival samples from the same site for 14 species, using whole genomic DNA probes and the "checkerboard" DNA-DNA hybridization technique . The findings indicate that, although a reduction of periodontal indices was noticed, plaque levels remained high (60%) even at the end of the experimental period . Periodontal pathogens including Porphyromonas gingivalis, Bacteroides forsythus and Actinobacillus actinomycetemcomitans were frequently detected both supragingivally and subgingivally (>30%) . The presence of a species supragingivally and the presence at the same time points subgingivally were correlated . This finding suggested that supragingival plaque acts as a reservoir for reinfection of treated sites . A reduction of the percentages of detection of these species was noticed 1 month after an oral hygiene period as well as at 3 and 6 months after treatment . Inadequate oral hygiene as performed by these patients probably affected supragingival, and consequently subgingival, plaque composition. J Clin Periodontol, 2001 Dec, 28(12), 1151 - 7 Sulfate-reducing bacteria in relation with other potential periodontal pathogens; Langendijk-Genevaux PS et al.; BACKGROUND, AIMS: Oral sulfate-reducing bacteria are involved in several clinical categories of periodontitis . The aim of this cross-sectional study was to compare the presence of sulfate-reducing bacteria (SRB) with other putative pathogens including spirochetes, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis, and Treponema denticola in periodontal lesions . METHOD: Periodontal SRB were detected by enrichment culture and compared with a microscopic spirochete count (n=168) . Species-specific oligonucleotide probes directed against the 16S rRNA were employed to determine the presence of A . actinomycetemcomitans, P . gingivalis, B . forsythus, and T . denticola (n=55) . RESULTS: A significant positive correlation was observed between the presence of SRB and the proportions of spirochetes in subgingival plaque, although the 2 bacterial groups also occurred separately . SRB tended to be negatively correlated with the presence of A . actinomycetemcomitans . In contrast, all pockets with SRB harbored either T . denticola, or both T . denticola and B . forsythus (12/14) before therapy . Interestingly, the combination of SRB with P . gingivalis occurred in 32% of the periodontal pockets before treatment . After initial periodontal therapy, the prevalence of this combination was reduced to 2% of the sites, and to 25% of the sites in recall patients . CONCLUSION: The presence of SRB was positively correlated with T . denticola, B . forsythus, and P . gingivalis in periodontal lesions . These suspected pathogens form a complex strongly associated with destructive periodontitis. Plasmid, 2001 Nov, 46(3), 202 - 9 Transfer region of a Bacteroides conjugative transposon contains regulatory as well as structural genes; Bonheyo GT et al.; Conjugative transposons (CTns) are integrated elements that excise themselves from the chromosome to form a circular transfer intermediate that is transferred by conjugation to a recipient . In an earlier paper, the excision step was shown to be regulated by tetracycline and to be dependent on the regulatory gene, rteC . In this paper, we report that genes involved in conjugal transfer are also regulated by tetracycline but that regulation is more complex . Genes contained within a 20-kbp region that is sufficient for conjugal transfer were disrupted by single crossover integration events . Most of the disruptions abolished transfer of the CTn . None of them abolished excision . Antibodies to two of the proteins encoded in this region (TraG and TraN) were obtained and used to show that production of these proteins was dependent on tetracycline stimulation . Both TraG and TraN were membrane proteins . A surprising finding was that a disruption in the gene traQ increased transfer of CTnERL over 100-fold . Thus, TraQ may be a repressor protein that controls expression of transfer genes . If so, TraQ is not the only protein that controls expression of transfer genes because production of TraG and TraN in the traQ disruption mutant was still dependent on tetracycline stimulation . Nature, 2001 Nov 29, 414(6863), 555 - 8 Extensive surface diversity of a commensal microorganism by multiple DNA inversions; Krinos CM et al.; The dynamic interactions between a host and its intestinal microflora that lead to commensalism are unclear . Bacteria that colonize the intestinal tract do so despite the development of a specific immune response by the host . The mechanisms used by commensal organisms to circumvent this immune response have yet to be established . Here we demonstrate that the human colonic microorganism, Bacteroides fragilis, is able to modulate its surface antigenicity by producing at least eight distinct capsular polysaccharides-a number greater than any previously reported for a bacterium-and is able to regulate their expression in an on-off manner by the reversible inversion of DNA segments containing the promoters for their expression . This means of generating surface diversity allows the organism to exhibit a wide array of distinct surface polysaccharide combinations, and may have broad implications for how the predominant human colonic microorganisms, the Bacteroides species, maintain an ecological niche in the intestinal tract. J Bacteriol, 2001 Dec, 183(24), 7224 - 30 Biochemical analysis of interactions between outer membrane proteins that contribute to starch utilization by Bacteroides thetaiotaomicron; Cho KH et al.; An early step in the utilization of starch by Bacteroides thetaiotaomicron is the binding of starch to the bacterial surface . Four starch-associated outer membrane proteins of B . thetaiotaomicron that have no starch-degrading activity have been identified . Two of these, SusC and SusD, have been shown by genetic analysis to be required for starch binding . In this study, we provide the first biochemical evidence that these two proteins interact physically with each other . Both formaldehyde cross-linking and nondenaturing gel electrophoresis experiments showed that SusC and SusD interact to form a complex . Two other proteins encoded by genes in the same operon, SusE and SusF, proved not to be essential for starch utilization and actually decreased starch binding when they were present along with SusC and SusD . Consistent with this, nondenaturing gel analysis revealed that in a strain producing SusC, SusD, and SusE, the SusCD complex was partially destabilized . The strain producing SusC, SusD, and SusE also grew more slowly on starch than a strain producing SusC, SusD, SusE, and SusF (mu(max), 0.29 and 0.37/h, respectively) . Thus, SusE appears to interact with the SusCD complex . SusE also interacts with SusF, because SusE was less susceptible to proteinase K digestion when SusF was present, and nondenaturing gel analysis detected a complex formed by these two proteins . Our results indicate that SusC, SusD, SusE, and SusF form a protein complex in the outer membrane but that SusE and SusF are dispensable members of this complex. J Bacteriol, 2001 Dec, 183(24), 7198 - 205 New regulatory gene that contributes to control of Bacteroides thetaiotaomicron starch utilization genes; Cho KH et al.; Bacteroides thetaiotaomicron uses starch as a source of carbon and energy . Early steps in the pathway of starch utilization, such as starch binding and starch hydrolysis, are encoded by sus genes, which have been characterized previously . The sus structural genes are expressed only if cells are grown in medium containing maltose or higher oligomers of glucose . Regulation of the sus structural genes is mediated by SusR, an activator that is encoded by a gene located next to the sus structural genes . A strain with a disruption in susR cannot grow on starch but can still grow on maltose and maltotriose . A search for transposon-generated mutants that could not grow on maltose and maltotriose unexpectedly located a gene, designated malR, which regulates expression of an alpha-glucosidase not controlled by SusR . Although a disruption in susR did not affect expression of the malR controlled gene, a disruption in malR reduced expression of the sus structural genes . Thus, MalR appears to participate with SusR in regulation of the sus genes . Results of transcriptional fusion assays and reverse transcription-PCR experiments showed that malR is expressed constitutively . Moreover, multiple copies of malR provided on a plasmid (5 to 10 copies per cell) more than doubled the amount of alpha-glucosidase activity in cell extracts . Our results demonstrate that the starch utilization system of B . thetaiotaomicron is controlled on at least two levels by the regulatory proteins SusR and MalR. Pesqui Odontol Bras, 2001 Jan-Mar, 15(1), 47 - 50 {Bacteroides forsythus: sensitivity to antimicrobial agents in samples from patients with periodontitis}; Lotufo RF et al.; An in vitro antimicrobial sensitivity test (technique of agar dilution) was carried out for 105 clinical isolates of B . forsythus from patients with periodontitis . Metronidazole and amoxicillin were the most efficient drugs and, thus, are indicated for the treatment of periodontal infections in which this microorganism is the most prevalent pathogen. South Med J, 2001 Oct, 94(10), 1021 - 2 Bacteroides peritonitis associated with colon cancer in a continuous ambulatory peritoneal dialysis patient; Nachimuthu S et al.; Peritonitis is not an uncommon complication of continuous ambulatory peritoneal dialysis (CAPD) . We report a case of Bacteroides fragilis-induced bacterial peritonitis, probably due to clinically occult malignancy, in a 76-year-old woman on CAPD. Am J Nephrol, 2001 Sep-Oct, 21(5), 410 - 2 Psoas abscess with osteomyelitis in a patient undergoing long-term hemodialysis; Kato A et al.; We describe a 69-year-old male patient on maintenance hemodialysis for 24 years who developed a fatal left psoas abscess with osteomyelitis at the hip joint following acute enterocolitis . He had systemic beta(2)-microglobulin amyloid deposition in colon epithelium and psoas muscle . Cultures from abscess fluid and femoral bone marrow yielded Bacteroides fragilis . To our knowledge, this is the first case on hemodialysis having a psoas abscess following acute gastrointestinal infection . This rare case suggested that a secondary psoas abscess could be one of the occult infections in patients undergoing long-term maintenance hemodialysis . Toxicon, 2001 Nov, 39(11), 1737 - 46 The toxins of Bacteroides fragilis; Sears CL; Bacteroides fragilis are both key commensals and important human pathogens . Particular strains of B . fragilis, termed enterotoxigenic B . fragilis (ETBF), are recently identified enteric pathogens of children and adults . These strains are distinguished by secretion of a 20kDa metalloprotease toxin (B . fragilis toxin or BFT), the first recognized and only established toxin to date for B . fragilis . Three isotypes of BFT are encoded by distinct bft loci contained within a 6kb chromosomal region unique to ETBF strains termed the B . fragilis pathogenicity island (BfPAI) . Experimental studies have suggested that the cellular target for BFT is E-cadherin, the primary protein of the zonula adherens . It is postulated that BFT cleavage of E-cadherin is critical in precipitating the intracellular events culminating in the two established activities for BFT; namely, stimulation of secretion in ligated intestinal segments in several animal species and alteration of cellular morphology only in epithelial cells that retain the ability to polarize and form a tight junctional complex . Future studies will be directed to characterizing in greater detail both the molecular genetics of the BFT toxin and the precise steps in its cellular mechanism of action. J Bacteriol, 2001 Nov, 183(21), 6335 - 43 Production of two proteins encoded by the Bacteroides mobilizable transposon NBU1 correlates with time-dependent accumulation of the excised NBu1 circular form; Wang J et al.; NBU1 is a mobilizable transposon that excises from the Bacteroides chromosome to form a double-stranded circular transfer intermediate . Excision is triggered by exposure of the bacteria to tetracycline . Accordingly, we expected that the expression of NBU1 genes would be induced by tetracycline . To test this hypothesis, antibodies that recognized two NBU1-encoded proteins, PrmN1 and MobN1, were used to monitor production of these proteins . PrmN1 is essential for excision, and MobN1 is essential for transfer of the excised circular form . At first, expression of the genes encoding these two proteins appeared to be regulated by tetracycline, because the proteins were detectable on Western blots only after the cells were exposed to tetracycline . However, when the prmN1 gene and/or the mobN1 gene was cloned on a multicopy plasmid, production of the protein was constitutive . Initially, we assumed that the constitutive expression was due to loss of a repressor protein that was encoded by one of the other genes on NBU1 . Deletions or insertions in the other genes (orf2 and orf3) on NBU1 and various integrated NBU1 derivatives abolished production of PrmN1 and MobN1 . This is the opposite of what should have happened if one or both of these genes encoded a repressor . A second possibility was that when NBU1 excised, it replicated transiently, increasing the gene dosage of prmN1 and mobN1 and thereby producing enough PrmN1 and MobN1 for these proteins to become detectable . In fact, after the cells entered late exponential phase the copy number of NBU1 increased to 2 to 3 copies per cell . Production of PrmN1 and MobN1 showed a similar pattern . Any mutation in NBU1 that decreased or prevented excision also prevented elevated production of these two proteins . Our results show that the apparent tetracycline dependence of the production of PrmN1 and MobN1 is due to a growth phase- or time-dependent increase in the number of copies of the NBU1 circular form. Clin Microbiol Rev, 2001 Oct, 14(4), 727 - 52, table of contents Periodontal disease as a specific, albeit chronic, infection: diagnosis and treatment; Loesche WJ et al.; Periodontal disease is perhaps the most common chronic infection in adults . Evidence has been accumulating for the past 30 years which indicates that almost all forms of periodontal disease are chronic but specific bacterial infections due to the overgrowth in the dental plaque of a finite number of mostly anaerobic species such as Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola . The success of traditional debridement procedures and/or antimicrobial agents in improving periodontal health can be associated with the reduction in levels of these anaerobes in the dental plaque . These findings suggest that patients and clinicians have a choice in the treatment of this overgrowth, either a debridement and surgery approach or a debridement and antimicrobial treatment approach . However, the antimicrobial approach, while supported by a wealth of scientific evidence, goes contrary to centuries of dental teaching that states that periodontal disease results from a "dirty mouth." If periodontal disease is demonstrated to be a risk factor for cardiovascular disease and stroke, it will be a modifiable risk factor since periodontal disease can be prevented and treated . Since the antimicrobial approach may be as effective as a surgical approach in the restoration and maintenance of a periodontally healthy dentition, this would give a cardiac or stroke patient and his or her physician a choice in the implementation of treatment seeking to improve the patient's periodontal condition so as to reduce and/or delay future cardiovascular events. Oral Microbiol Immunol, 2001 Oct, 16(5), 311 - 5 Immune response to Bacteroides forsythus in a murine model; Bird PS et al.; A murine skin abscess model was used to study the immune response to an acute infection with Bacteroides forsythus . BALB/c mice were given subcutaneous injections of either viable or heat-killed B . forsythus, while a third sham-immunized control group received phosphate-buffered saline . Weights and lesion sizes were measured . Blood was collected from the heart and specific antibodies to B . forsythus measured by an ELISA . Swabs taken from the lesions and also from pooled blood were cultured anaerobically for viable B . forsythus . Viable B . forsythus-induced lesions reached maximum size at day 7 . B . forsythus cells were recovered from lesions up to day 4 although none were cultured from blood samples . Heat-killed bacteria induced much smaller lesions . Serum antibody levels increased during the 9-day study period, being significantly higher in mice injected with viable compared with heat-killed B . forsythus . Antibody levels in sham control mice were significantly lower than those seen in the other two groups . These results showed that a subcutaneous injection of viable cells of B . forsythus elicited a pronounced abscess formation and induce higher levels of specific antibodies compared with that produced by an injection of dead bacteria . This suggests that, as with other periodontopathic organisms, this mouse model can be used to study the immune response to B . forsythus. J Oral Pathol Med, 2001 Oct, 30(9), 553 - 9 Salivary albumin, total protein, IgA, IgG and IgM concentrations and occurrence of some periodontopathogens in HIV-infected patients: a 2-year follow-up study; Mellanen L et al.; HIV infection reduces oral defensive mechanisms and may affect mucosal integrity . Differences in salivary protein concentrations and periodontopathogenic bacteria were studied in 56 HIV-infected patients with respect to their disease phase . Thirty-three patients were followed up for 2 years . Fifty-three healthy subjects of corresponding age and sex were studied as controls . At baseline, salivary albumin, total protein, IgA, and IgM levels were significantly higher (P<0.05-0.0001) in all phases of HIV infection, except the asymptomatic (ASX) phase, when compared with the control group . IgG levels were significantly increased in all phases except the ASX phase (P<0.05) . After 2 years, salivary total protein, IgG, and IgM levels were still higher (P<0.05-0.005) in all HIV phases when compared with the control group (P<0.05-0.005) . The albumin level was significantly higher in the ASX phase (P<0.005) and in the AIDS-related complex phase (ARC) (P<0.05), while the increase in IgA level was significant only in the ARC phase (P<0.005) . Periodontopathogenic bacteria analyzed by PCR were detected both in the patients and the non-infected, but a statistically significant difference in the carriage percentage between the follow-up lymphadenopathy syndrome phase (LAS) and the control group was found only in Porphyromonas gingivalis (P<0.05) and Bacteroides forsythus (P< 0.0001) . Thus, HIV infection appeared to cause a significant increase in the studied salivary proteins, suggesting leakage of serum components into the mouth. Infect Immun, 2001 Oct, 69(10), 6044 - 54 Molecular cloning of a Bacteroides caccae TonB-linked outer membrane protein identified by an inflammatory bowel disease marker antibody; Wei B et al.; Commensal enteric bacteria are a required pathogenic factor in inflammatory bowel disease (IBD), but the identity of the pertinent bacterial species is unresolved . Using an IBD-associated pANCA monoclonal antibody, a 100-kDa protein was recently characterized from an IBD clinical isolate of Bacteroides caccae (p2Lc3) . In this study, consensus oligonucleotides were designed from 100-kDa peptides and used to identify a single-copy gene from the p2Lc3 genome . Sequence analysis of the genomic clone revealed a 2,844-bp (948 amino acid) open reading frame encoding features typical of the TonB-linked outer membrane protein family . This gene, termed ompW, was detected by Southern analysis only in B . caccae and was absent in other species of Bacteroides and gram-negative coliforms . The closest homologues of OmpW included the outer membrane proteins SusC of Bacteroides thetaiotaomicron and RagA of Porphyromonas gingivalis . Recombinant OmpW protein was immunoreactive with the monoclonal antibody, and serum anti-OmpW immunoglobulin A levels were elevated in a Crohn's disease patient subset . These findings suggest that OmpW may be a target of the IBD-associated immune response and reveal its structural relationship to a bacterial virulence factor of P . gingivalis and periodontal disease. Minerva Stomatol, 2001 Jun, 50(6), 219 - 28 {Systemic antimicrobial treatment of prosthesis related infections: a comparative study of ornidazole and minocycline . A microbiological evaluation and experimental protocol}; Stellini E et al.; BACKGROUND: The aim of this study was to evaluate the efficacy of two chemotherapeutic agents against bacterial forms responsible for prosthesis-related infections . METHODS: The evaluation was made on the basis of a count using optical microscope 1000x after GRAM staining of the main bacterial forms found in periprosthetic inflammatory exudate both before and after treatment . Two drugs used: ornidazole and minocycline . A group of 20 patients were studied (12 women and 8 men) aged between 42 and 71 years old with an advanced stage of periprosthetic inflammatory pathology . The pharmacological protocol was administered to the two groups of patients for a period of approximately 15 days . RESULTS: At the end of treatment there was a marked reduction in all the bacterial forms involved in periprosthetic pathology in both groups, with a gradual recovery of normal bacterial flora (gram forms) coupled with a clinical improvement in the implant sites examined . CONCLUSIONS: Given the specificity of action shown by ornidazole against pathogenic anaerobic, gram-; bacteroides and sporigenic forms, it is recommended for systemic use against prosthesis-related inflammatory disease. Plasmid, 2001 Jul, 46(1), 47 - 56 Analysis of a Bacteroides conjugative transposon using a novel "targeted capture" model system; Smith CJ et al.; Large conjugative transposons (CTn's) are widespread among Bacteroides spp . and they are responsible for the high rates of Bacteroides tetracycline resistance, which is mediated by the tetQ gene . These elements are self-transmissible and conjugation can be induced up to 1000-fold by the addition of tetracycline to cultures prior to mating . In addition to self-transfer, the Bacteroides CTn's, such as CTn341, are able to mobilize unlinked genetic elements such as plasmids and mobilizable transposons in a tetracycline-inducible manner . To study the molecular properties of these unique elements, a vector was designed to capture CTn's for analysis in heterologous hosts . This plasmid, pFD670, consisted of the low-copy vector pWSK29, the RK2 oriT, an ermF gene, and a tetQ gene fragment containing the N-terminus and promoter . The vector was transferred into Bacteroides recipients containing CTn341 where it integrated into the tetQ gene by homologous recombination . This integrated construct then was transferred back into an Escherichia coli host where it replicated as a plasmid, pFD699, about 56 kb in size . Further analysis showed that pFD699 could be transferred into Bacteroides hosts where it displayed the same tetracycline-inducible properties as the native CTn341 . The captured element appeared to utilize a circular intermediate in both transfer and transposition, and integration into the chromosome seemed to be random . Hybridization studies with a range of Bacteroides CTn's encoding tetracycline resistance revealed a great deal of homology between most of the CTn's but there was much variation seen in the restriction patterns of these elements, suggesting great diversity among this group . Mol Microbiol, 2001 Aug, 41(3), 625 - 32 Identification of genes required for excision of CTnDOT, a Bacteroides conjugative transposon; Cheng Q et al.; Integrated self-transmissible elements called conjugative transposons have been found in many different bacteria, but little is known about how they excise from the chromosome to form the circular intermediate, which is then transferred by conjugation . We have now identified a gene, exc, which is required for the excision of the Bacteroides conjugative transposon, CTnDOT . The int gene of CTnDOT is a member of the lambda integrase family of recombinases, a family that also contains the integrase of the Gram-positive conjugative transposon Tn916 . The exc gene was located 15 kbp from the int gene, which is located at one end of the 65 kbp element . The exc gene, together with the regulatory genes, rteA, rteB and rteC, were necessary to excise a miniature form of CTnDOT that contained only the ends of the element and the int gene . Another open reading frame (ORF) in the same operon and upstream of exc, orf3, was not essential for excision and had no significant amino acid sequence similarity to any proteins in the databases . The deduced amino acid sequence of the CTnDOT Exc protein has significant similarity to topoisomerases . A small ORF (orf2) that could encode a small, basic protein comparable with lambda and Tn916 excision proteins (Xis) was located immediately downstream of the CTnDOT int gene . Although Xis proteins are required for excision of lambda and Tn916, orf2 had no effect on excision of the element . Excision of the CTnDOT mini-element was not affected by the site in which it was integrated, another difference from Tn916 . Our results demonstrate that the Bacteroides CTnDOT excision system is tightly regulated and appears to be different from that of any other known integrated transmissible element, including those of some Bacteroides mobilizable transposons that are mobilized by CTnDOT. J Periodontal Res, 2001 Aug, 36(4), 237 - 43 Mixed infection of Porphyromonas gingivalis and Bacteroides forsythus in a murine abscess model: involvement of gingipains in a synergistic effect; Yoneda M et al.; Several microorganisms including Porphyromonas gingivalis and Bacteroides forsythus have been implicated to be etiologically important agents of periodontal disease . In this study, we determined the ability of combinations of periodontopathogenic microorganisms to cause tissue destruction in a murine abscess model . Although all bacterial combinations used in this study produced larger abscesses than did monoinfection of each bacterium, the combination of P . gingivalis and B.forsythus showed a synergistic effect on abscess formation . Since these two bacteria have been frequently found together in lesions of periodontitis, these results suggest the significance of their co-infection in the progression of periodontitis . P . gingivalis produces extracellular and cell-associated cysteine proteinases (gingipains) which appear to be involved in its virulence . The rgpA rgpB double and kgp mutants induced significantly smaller abscesses than the wild type . Moreover, the rgpA rgpB kgp triple (gingipain-null) mutant hardly showed lesion formation at all with the experimental conditions used in this study, indicating that these genes encoding gingipains are important for virulence of P . gingivalis . Mixed infection of these P . gingivalis mutants with B . forsythus showed an additive effect on abscess formation, indicating that the gingipains of P . gingivalis may play an important role in the pathological synergism between P . gingivalis and B . forsythus. J Periodontal Res, 2001 Aug, 36(4), 227 - 32 Humoral immune response in early-onset periodontitis: influence of smoking; Mooney J et al.; Sixty-five patients with generalised early-onset periodontitis (G-EOP) (age range 16-42 years, 32 smokers and 33 non-smokers) were assessed for antibody titres and avidity to a panel of five suspected periodontal pathogens (Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Treponema denticola and Bacteroides forsythus) . Thirty-four of these patients were untreated (17 smokers and 17 non-smokers), and thirty-one were in the maintenance phase of periodontal therapy (15 smokers and 16 non-smokers) . Previous studies have investigated the effect of smoking on IgG levels in periodontitis patients in the context of the more extensive periodontal destruction seen in smokers . Based on this literature our hypothesis was that smokers would have depressed serum IgG levels directed against recognised periodontal pathogens compared with non-smokers . Antibody titres were measured by ELISA deploying fixed whole cells as coating . The IgG response was detected with biotin-anti-human IgG and avidin-peroxidase; avidity was determined by elution with ammonium thiocyanate . Median titres to A . actinomycetemcomitans, P . intermedia and T . denticola were significantly lower in maintenance patient smokers (p= 0.02, 0.02 and 0.002 respectively) but not in untreated patients . Avidity to P . gingivalis was also lower in smoking maintenance patients (p = 0.003) but not in untreated patients . These findings may imply some interruption of immune maturation in smokers following periodontal treatment. Int J Antimicrob Agents, 2001 Aug, 18(2), 129 - 34 Antimicrobial resistance of strains of the Bacteroides fragilis group isolated from the intestinal tract of children and adults in Brazil; Avelar KE et al.; The results of this study show that there is a high frequency of resistant species in the Bacteroides fragilis group in the intestinal tract of children and adults in Brazil . B . fragilis was not studied . Of the 73 strains examined, B . distasonis was the most resistant species to penicillin, cefoxitin, cefotaxime and clindamycin . High rates of multiresistance were found, most commonly to penicillin and clindamycin (18 of 36 strains) . High levels of beta-lactamase production were detected in isolates showing high resistance to penicillin and multiresistance to the cephamycins, suggesting a widespread dissemination of such resistance. Folia Microbiol (Praha), 2001, 46(1), 79 - 82 Isolation and characterization of rabbit caecal pectinolytic bacteria; Sirotek K et al.; Two hundred and thirty colonies from the caecal contents of six rabbits were picked up and, after a 2-d incubation, were microscopically characterized using Gram staining . Large Gram-negative (34%) and small Gram-negative (30%) irregular rods, Gram-negative (27%) and Gram-positive (8%) cocci were found . Eleven isolates (Bacteroides ovatus (6 strains), B . thetaiotamicron, B . caccae, B . stercoris, B . capillosus and Capnocytophaga ochracea) were identified using commercial tests for measuring their catalase activity, metabolite production, etc., and testing their growth in 20% bile . Bacteria belonging to the genus Bacteroides were demonstrated to be the principal pectinolytic organisms in the rabbit caecum. Folia Microbiol (Praha), 2001, 46(1), 40 - 4 Systematics and evolution of ruminal species of the genus Prevotella; Avgustin G et al.; Bacterial species of the genus Prevotella represent a numerically dominant microbial population in the rumen of cattle . They belong to the phylogenetic division Cytophaga-Flexibacter-Bacteroides (CFB) which is a large group of ecologically diverse bacteria with only a few shared traits . The phylogenetic descent from a common ancestor seems to be unquestionable, however, as judged from the small subunit ribosomal RNA analysis . Only 4 ruminal Prevotella species have been described to date, even though the sequence analysis of directly retrieved 16S rRNA genes indicates a large genetic diversity within this group of rumen bacteria . The closest relatives of ruminal Prevotella spp . are not surprisingly other species of the genus Prevotella, typically inhabiting the gastrointestinal tract, oral cavity and genital areas of other animals and man . The previous phylogenetic analysis showed that species of the genus Prevotella can be split into two groups or superclusters, the "ruminal" and the "non-ruminal prevotellas" . One of 4 currently described ruminal Prevotella spp., i.e . P . albensis, has been placed outside the supercluster containing ruminal Prevotella spp . and within the supercluster containing the non-ruminal Prevotella spp . However, the number of available small subunit rRNA sequences from this species represents only a fraction of all known ruminal Prevotella sequences. Spine, 2001 Aug 15, 26(16), E377 - 8 Bacteroides fragilis vertebral osteomyelitis secondary to anal dilatation; Chazan B et al.; STUDY DESIGN: A case report of anaerobic vertebral osteomyelitis after anal dilatation . OBJECTIVES: To present a patient with monomicrobial anaerobic vertebral osteomyelitis secondary to a previously undescribed source of infection . SUMMARY OF BACKGROUND DATA: A 17-year-old boy presented with low back pain 3 months after anal dilatation . METHODS: Physical examination, technetium-99m bone scan, plain radiograph, CT, and MRI studies of the lumbar spine were used to clinically diagnose lumbar osteomyelitis . Culture material from the involved disc was positive for Bacteroides fragilis . RESULTS: The patient recovered after 8 weeks of treatment with oral metronidazole . CONCLUSIONS: Bacteroides<