Ulceraçöes aftosas recorrentes bucais: estudo microbiológico / Recurrent aphthous oral ulcers: a microbiologic study

Realizamos estudo microbiológico, coletando amostras de ulceraçöes aftosas recorrentes (UAR) bucais, em 30 pacientes, 18 mulheres e 12 homens, através de "swabs", buscando verificar a participaçäo de bactérias gram-negativas nessas lesöes. Outros 30 pacientes pareados por idade, sexo e estado de saúde bucal, mas com história negativa de UAR foram utilizados como populaçäo controle. Apenas três pacientes do grupo estudo mostraram culturas positivas para gram-negativos (Klebsiella e Enterobacter), enquanto seis pacientes do grupo controle abrigavam enterobactérias. Todas as amostras, tanto do grupo estudo quanto do controle apresentaram crescimento de estreptococos alfa-hemolíticos. Conclui-se que as bactérias gram-negativas näo desempenham papel relevante na expressäo das UAR, uma vez que näo foi possível estabelecer qualquer relaçäo entre as culturas positivas e as características clínicas dos pacientes ou das lesöes em particular. Os estudos devem se aprofundar quanto aos aspectos de identificaçäo, aderência e virulência dos estreptococos alfa-hemolíticos isolados

Hemagglutinins of Klebsiella pneumoniae and K. oxytoca isolated from different sources.

482 Klebsiella pneumoniae and K. oxytoca strains isolated from different sources (human clinical material, feces of healthy subjects, sewage) were investigated for expression of MS-(mannose-sensitive) and MR/K-(mannose-resistant, Klebsiella-like) hemagglutinins. Regardless of the source of isolation, the majority of K. pneumoniae strains induced mannose-sensitive hemagglutination, but very few K. oxytoca isolates produced this type of hemagglutinin. In both species, most strains induced MR/K-hemagglutination. In general, environmental isolates showed a lesser incidence in production of each hemagglutinin and a higher percentage of non-hemagglutinating strains than fecal and clinical strains. These results suggest clinical isolates to be phenotypically more related to fecal than to environmental strains.

Comparison of SDS-PAGE protein patterns with other typing methods for investigating the epidemiology of 'Klebsiella aerogenes'.

Twenty-four cultures comprising 20 clinical isolates of 'Klebsiella aerogenes' from two hospitals, a reference strain of 'K. aerogenes' and the type strains of three other Klebsiella species, were characterized by one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell proteins. The protein patterns were highly reproducible and were used as the basis of a numerical analysis which divided the clinical isolates into 12 protein types. Comparison with established typing methods indicated that the level of discrimination of SDS-PAGE was similar to that achieved with conventional typing methods but the strains were grouped differently. Protein typing subdivided five serotype K3 isolates that could also be distinguished by phage typing. Conversely, three strains of protein type 11 were clearly distinguishable by both serotyping and phage typing. We conclude that high-resolution SDS-PAGE of proteins provides an effective adjunct to other methods for typing isolates of 'K. aerogenes'.

The use of bacteriophage-mediated depolymerisation in investigations of the structure of the capsular polysaccharide from Klebsiella serotype K71.

The structure (1) of the heptasaccharide repeating-unit of the capsular polysaccharide from Klebsiella serotype K71 follows from methylation analysis and n.m.r. and mass-spectrometric studies of the oligosaccharides obtained on depolymerisation of the polysaccharide with a bacteriophage-borne endo-rhamnosidase. [formula; see text].

Cytotoxic component(s) of Klebsiella oxytoca on HEp-2 cells.

A cytotoxic component(s) was detected in culture filtrates of Klebsiella oxytoca isolated from patients with antibiotic-associated hemorrhagic colitis. Eleven of 12 isolates exhibited cytotoxicity on HEp-2 cells. The cytotoxic activity of K. oxytoca strain MH43-1 was stable for the treatment of 60 C for 30 min, but inactivated by the treatment of 100 C for 15 min. This cytotoxicity was not destroyed by the treatment with trypsin or pronase, and the component was filtrable through a membrane filter which cut off molecular weight 5,000.

A re-investigation of the structure of the capsular polysaccharide of Klebsiella K10.

The capsular polysaccharide of Klebsiella K10 was investigated by methylation analysis and 1H-n.m.r. spectroscopy, and the deacetylated bacteriophage-degraded polysaccharide by 1D- and 2D-n.m.r. spectroscopy. The repeating unit was shown to be a branched hexasaccharide (see text). OAc substituents were located on the terminal and 2-linked galactopyranosyl residues by Prehm methylation of a low-molecular-weight fraction obtained by bacteriophage degradation.

Structural studies of an extracellular polysaccharide (K21b) elaborated by Klebsiella type 21b.

The capsular polysaccharide from a new capsular serotype of Klebsiella, K21b, has been investigated, using n.m.r. spectroscopy, methylation analysis, and specific degradations as the main methods. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text)

Proof of the occurrence of 5,6-O-(1-carboxyethylidene)-D-galactofuranose units in the capsular polysaccharide of Klebsiella K12.

The 13C-n.m.r. spectra of the capsular polysaccharide of Klebsiella K41 and phage-derived oligosaccharides K41-P1 and K41-P2 were compared with spectra from the structurally similar polysaccharide of Klebsiella K12 and oligosaccharides K12-P1 and K12-P2. This led to the conclusion that K41 and K12 contain one and two galactofuranose residues per repeating unit, respectively, and that the terminal, lateral residue in K12 has the 5,6-O-(1-carboxyethylidene)-D-galactofuranose structure rather than that of a 4,6-acetal of D-galactopyranose as originally stated. This is the first reported occurrence in Nature of such a structural unit.

Chromotropic character of bacterial acidic polysaccharides: Part II--Induction of metachromasy in cationic dye pinacyanol chloride by Klebsiella K10 capsular polysaccharide.

The acidic capsular polysaccharide isolated from Klebsiella K10 exhibited chromotropic character with respect to induction of metachromasy in the cationic dye pinacyanol chloride (1-ethyl-2-[3-(1-ethyl-2(1H)-quinolylidene)propenyl]quinolinium chloride). Klebsiella K10 polymer consists of hexasaccharide repeating units containing one residue of glucuronic acid along with other neutral sugars in each repeating unit. It induces a metachromatic blue shift in the visible absorption spectrum of the dye from 600 nm to 500 nm. The spectral changes have been studied during interaction of the dye cations with the polyanions at different polymer/dye molar ratios. The polyanion-dye compounds are formed with polymer/dye stoichiometry of 1:1, indicating formation of stacking conformation. The complete reversal of polymer-induced metachromasy has also been observed by the addition of ethanol and urea.

Escherichia coli serotype-39 capsular polysaccharide: primary structure and depolymerisation by a bacteriophage-associated glycanase.

The acidic capsular polysaccharide isolated from Escherichia coli O9:K39:H9 was investigated, using n.m.r. spectroscopy, methylation analysis, uronic acid degradation of the native and methylated polysaccharides, and bacteriophage-associated enzyme degradation. The structure of the repeating unit, which is shown below, is identical to that reported for Klebsiella serotype-61 capsular polysaccharide. (formula; see text)

Enzyme-linked immunosorbent assay to evaluate the immunogenicity of a polyvalent Klebsiella capsular polysaccharide vaccine in humans.

A highly sensitive enzyme-linked immunosorbent assay was developed for Klebsiella capsular polysaccharide (CPS) and used to evaluate the immunoglobulin G (IgG) antibody response to a 24-valent CPS vaccine in seven adult volunteers. The median rise in titer to all vaccine antigens in samples from the volunteers was significant (twofold or greater). Significant IgG responses to 11 immunologically related serotypes not included in the vaccine were also noted. The mean cross-reacting IgG titer of 127.2 was only slightly lower than the mean titer of 175.7 to the serotypes in the vaccine (P less than 0.05). The mean 29.9-fold increase in titer to the serotypes in the vaccine was significantly higher than the mean 13.5-fold increase in titer to the additional antigens (P less than 0.001). The difference was partly because of the significantly lower (P less than 0.01) natural antibody titers in the preimmune sera to the serotypes in the vaccine, compared with those to serotypes not included in the vaccine. The selection of vaccine serotypes was based on the frequency of serotype isolation from cases of Klebsiella bacteremia. The above findings, which show low levels of natural antibody to these serotypes, support the hypothesis that anti-CPS antibody is protective against bacteremic disease.

Primary structure of Klebsiella serotype K22 capsular polysaccharide: another glycan containing 4-O-[(S)-1-carboxyethyl]-D-glucuronic acid.

The primary structure of the acidic capsular polysaccharide isolated from Klebsiella serotype K22 has been investigated using methylation analysis, hydrolysis, bacteriophage-borne enzyme degradation, and n.m.r. spectroscopy. The repeating unit comprises the chain disaccharide----3)-beta-D-Galp-(1----4)-beta-D-Glcp-(1---- substituted by 4-O-[(S)-1-carboxyethyl]-beta-D-GlcpA-(1----6)-alpha-D-Glcp-(1---- at O-4 of the galactose. The galactose carries an O-acetyl group on position 6.

The structural repeating-unit of the capsular polysaccharide from Klebsiella serotype K48.

Investigation of the structure of the capsular polysaccharide from Klebsiella K48, using methylation analysis, periodate oxidation, Smith degradation, and 1H- and 13C-n.m.r. spectroscopy, indicated the repeating unit to be the pentasaccharide (formula; see text)

Anti-Klebsiella K30 phospholipid antibodies in systemic lupus erythematosus: antigen cross-reactions and idiotypic sharing with antibodies to DNA and Klebsiella K30 polysaccharide.

Patients with systemic lupus erythematosus were examined for the presence of serum antibodies reactive with phospholipids (PL) extracted from the membranes of Klebsiella K30 (K30PL). Affinity-purified anti-K30PL antibodies were tested for their ability to cross-react with other PL antigens or DNA and for the presence of idiotypic markers known to be associated with anti-DNA antibodies or antibodies to Klebsiella K30 polysaccharide (K30p). Affinity-purified antibodies to K30PL, phosphatidylserine (PS), or phosphatidylinositol (PL) uniformly cross-reacted with each other. Analysis of the PL preparations by thin-layer chromatography and reversed-phase high-performance liquid chromatography (HPLC) showed the presence of several components. Lupus sera reacted with one component mainly in the HPLC-fractionated K30PL preparation, although this component appeared to be present in the other PL preparations. Direct-binding and inhibition studies showed that affinity-purified antibodies to the K30PL extract, PS, or PI reacted poorly with DNA. However, the anti-K30PL antibodies possessed a prominent anti-DNA idiotypic marker (AM Id) in 61% of the patients and an anti-K30p idiotypic marker (SP Id) in 94% of the patients. The results thus show that anti-K30PL antibodies are idiotypically related to anti-DNA and anti-K30p antibody subpopulations, although they do not share the same antigen-binding characteristics.

Structural investigation of Klebsiella serotype K10 capsular polysaccharide.

The primary structure of Klebsiella serotype K10 capsular polysaccharide has been investigated using mainly the techniques of methylation, partial hydrolysis, and 1H and 13C NMR spectroscopy. The polysaccharide was found to consist of hexasaccharide repeating units having the following structure: (formula; see text)

Studies of the primary structure of the capsular polysaccharide from Klebsiella serotype K15.

The capsular polysaccharide of Klebsiella serotype K15 has been investigated mainly by methylation analysis, characterisation of the oligosaccharides obtained by partial acid hydrolysis, periodate oxidation, enzymic degradation, and 1H- and 13C-n.m.r. spectroscopy, and shown to have the hexasaccharide repeating-unit 1. The glycan does not contain any pyruvic acetal or O-acetyl substituents. (formula; see text)

Detection of acetoin by head-space gas-liquid chromatography for rapid identification of bacteremia caused by Klebsielleae.

Head-space gas-liquid chromatographic (HS-GLC) detection of acetoin in 223 blood cultures of gram-negative bacilli was compared with results obtained from the conventional identification method. Seventy-three out of 76 cultures of Klebsielleae, including Klebsiella pneumoniae, Klebsiella oxtytoca, Enterobacter cloacae, Enterobacter agglomerans and Serratia marcescens, were identified by the acetoin detection method with HS-GLC. One hundred and forty-six out of 147 blood cultures of other gram-negative aerobic and anaerobic bacilli did not produce acetoin. The findings indicate that the HS-GLC technique is a useful method with high sensitivity and specificity for identification of bacteremia caused by Klebsielleae.

Structural studies on the capsular polysaccharide of Klebsiella serotype K40.

The capsular polysaccharide of Klebsiella serotype K40 contained D-mannose, D-glucuronic acid, D-galactose, and L-rhamnose in the approximate molar ratios 1:1:1:2. The primary structure of the capsular polysaccharide has been investigated mainly by methylation analysis, periodate oxidation, characterization of oligosaccharides, base degradation reaction, and 1H and 13CNMR spectroscopy. The polysaccharide does not contain any pyruvic acetal or O-acetyl substitution. It has a pentasaccharide repeating unit of the following primary structure: alpha-D-Manp 1----4 ----4)-beta-D-GlcpA-(1----2)-alpha-L-Rhap-(1----3)-beta-D-Ga lp-(1----2)-alpha- L-Rhap-(1----.

Structural investigation of the capsular polysaccharide from Klebsiella K19 by chemical and N.M.R. analyses.

Sugar analysis of the capsular antigen K19 from Klebsiella and of the carboxyl-reduced derivative confirmed its classification into the chemotype containing rhamnose, galactose, glucose, and glucuronic acid residues. Partial acid hydrolysis and phage depolymerization of K19 provided respectively a modified, linear form of the polysaccharide and oligosaccharides of the repeating unit, these were used for the structural elucidation of the original polymer. Methylation analysis, Smith degradation, and 1H- and 13C-n.m.r. spectroscopy of the polysaccharide and derivatives permitted formulation of the following structure for K19: (formula; see text)

Depolymerization of the capsular polysaccharide from Klebsiella K19 by the glycanase associated with particles of Klebsiella bacteriophage luminal diameter 19.

The site of cleavage of the capsular polysaccharide from Klebsiella K19 by the endoglycanase associated with particles of Klebsiella bacteriophage luminal diameter 19 was determined. The specific cleavage of the bond Rhap-(1----2)-Rhap provided a series of oligosaccharides having rhamnose at the reducing end. The enzyme is thus an alpha-rhamnosidase. Structural studies on the oligomers confirmed the sequence of the repeating unit of the polysaccharide from K19. The 1H- and 13C-n.m.r. spectra of the homologous series of oligosaccharides corresponding to one, two, three, and four repeat-units exhibit important differences that denot variation of conformation with chain length. The bacteriophage acted on modified forms of K19 polysaccharide to provide a series of linear oligomers, and emphasized the essential role of the negative charge on the uronic acid in the action of the glycanase.