Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0519030 (Klebsiella)
 21,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The different mechanisms of Klebsiella pneumoniae resistance to complement-mediated killing were investigated by using different strains and isogenic mutants previously characterized for their surface components. We found that strains from serotypes whose K antigen masks the lipopolysaccharide (LPS) molecules (such as serotypes K1, K10, and K16) fail to activate complement, while strains with smooth LPS exposed at the cell surface (with or without K antigen) activate complement but are resistant to complement-mediated killing. The reasons for this resistance are that C3b binds far from the cell membrane and that the lytic final complex C5b-9 (membrane attack complex) is not formed. Isogenic rough mutants (K+ or K-) are serum sensitive because they bind C3b close to the cell membrane and the lytic complex (C5b-9) is formed.
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PMID:Mechanisms of Klebsiella pneumoniae resistance to complement-mediated killing. 158 19

Surface exposure of the O1 serotype lipopolysaccharide in encapsulated Klebsiella pneumoniae strains belonging to different serotypes was examined by using the O1 antigen-specific bacteriophages FC3-1 and FC3-2 in conjunction with immunogold electron microscopy and enzyme immunoassays with specific antisera. Despite the presence of the capsular polysaccharide, the O1 antigen was exposed at the cell surface in strains producing K2, K7, K8, K12, K19, K21, K22, K34, K35, K42, K45, K55, K57, K62, K66, K69, and K70 capsular polysaccharides. However, in strains producing K1, K10, and K16 capsular polysaccharides, the O1 antigen was masked by the K antigen. These results suggest that, since the O1 antigen is surface exposed in many different strains of K. pneumoniae with different capsular serotypes and is also able to immunoprotect, its potential as a useful vaccine component should not be overlooked.
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PMID:Surface exposure of O1 serotype lipopolysaccharide in Klebsiella pneumoniae strains expressing different K antigens. 170 19

Examination of 278 newborn infants, parturients, and medical personnel in two maternity hospitals revealed a high level of Klebsiella colonization of all examined biotopes of infants (the nasal cavity in up to 36.5% of cases) and the skin of the mammary glands of nursing mothers (in 36.2% of cases). In the intestine and the nasal cavity of parturient women and medical personnel Klebsiella could be detected 3-10 times more often than in the same biotopes of nonhospitalized pregnant women. From 254 objects of the hospital environment Klebsiella were isolated in 9.05% of cases. The possibility of the transmission of Klebsiella in hospitals by patients with inflammatory processes in their genitals were established. The diversity of the serological picture of strains of most K-serovars and a short period of their isolation were shown. In one hospital serovar K10 with some features of a "hospital" strain was isolated. The strains under study were sensitive to aminoglycosides, cephamesine, chlorhexidine, but resistant to semisynthetic penicillins and chloramine.
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PMID:[The spread of Klebsiella in obstetrical hospitals and the biological properties of the isolated strains]. 183 34

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.
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PMID:A re-investigation of the structure of the capsular polysaccharide of Klebsiella K10. 261 80

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.
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PMID:Chromotropic character of bacterial acidic polysaccharides: Part II--Induction of metachromasy in cationic dye pinacyanol chloride by Klebsiella K10 capsular polysaccharide. 277 22

Klebsiella vaccines were isolated by mild diafiltration techniques from culture filtrates of nine capsular types of K. aerogenes (K1, K2, K3, K15, K20, K35, K36, K44 & K63). The bacteria were grown in a chemically defined medium in standardized conditions in a fermenter. The vaccines had a molecular weight of more than 20 000, a carbohydrate content of 40-89%, a protein content of between less than 1 and 16% and small amounts (0.6-1.2%) of lipopolysaccharide. Antisera raised in rabbits to the nine klebsiella vaccines were standardized by passive haemagglutination, immunoglobulin G enzyme-linked immunosorbent assay and by autologous passive protection tests. Each rabbit antiserum when passively transferred to mice showed a variable capacity to passively protect mice against lethal infections by a panel of ten capsular types of K. aerogenes (K1-K10). Seven of the rabbit antisera protected mice against more than half of the challenge strains. A pool of six rabbit antisera (anti-K1, K2, K3, K20, K35 & K44) passively protected mice against lethal infections from strains of bacteria representing each of 77 capsular types of K. aerogenes.
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PMID:Passive immunization of mice against Klebsiella aerogenes. 351 39

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)
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PMID:Structural investigation of Klebsiella serotype K10 capsular polysaccharide. 383 Jan 82

A polyvalent Klebsiella vaccine composed of six serotypes of capsular polysaccharides (K2, K3, K10, K21, K30, and K55) was developed and its safety and immunogenicity evaluated in humans. Highly purified capsular antigens were treated in 0.1 N NaOH in 95% ethanol to detoxify trace amounts of contaminating lipopolysaccharide (LPS). The vaccine was nontoxic and nonpyrogenic for animals. A total of 40 individuals received either 25 or 50 micrograms of each represented antigen subcutaneously. Reactions to vaccination, where noted, were transient and mild in nature. An immunizing dose of 50 micrograms of each antigen (300 micrograms total) elicited a fourfold or greater immunoglobulin G (IgG) response to all vaccine antigens in greater than 80% of vaccinees. Generally, the serospecificity of the antibody response was limited to those capsular antigens included in the vaccine. IgG isolated from the serum of vaccinees was found to be highly protective against fatal experimental Klebsiella K2 burn wound sepsis indicating that the functional antibody is elicited following vaccination.
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PMID:Safety and immunogenicity of a polyvalent Klebsiella capsular polysaccharide vaccine in humans. 396 47

457 Klebsiella strains isolated from newborns and young children with different clinical manifestations of infections, as well as from adults having contacts with them and from various objects of the environment in the foci of these infections, have been studied. All the isolated cultures, with the exception of one strain isolated from the pus of a gluteal abscess and identified as K. ozaenae K4, have been identified as K. pneumoniae. The use of experimental Klebsiella K-sera has allowed one to establish the presence of 27 K-antigen varieties in K. pneumoniae; among them K2, K9, K10, K13, K18, K20, K24, K33, K46, K47 have been found to occur most frequently . In group diseases of infants serovars K2, K9, K10, K18, K20, K24, K33 have been identified, serovars K9, K10 and K20 being detected for the first time in such cases. The data confirming the etiological role of the isolated Klebsiella organisms point out to the necessity of maintaining the constant microbiological control of Klebsiella infection in maternity homes and children's somatic hospitals.
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PMID:[Results of identifying Klebsiella in various diseases of newborn and young infants]. 712 10

The capsular polysaccharide (CPS) of Klebsiella pneumoniae is an important virulence factor. Salicylate, which inhibits CPS production, was used to expose subcapsular antigens and components that may play an important role in host defense. Salicylate treatment greatly increased phagocytosis of five O1 serotypes by human polymorphonuclear leukocytes with normal rabbit serum and rabbit antisera against purified O1 lipopolysaccharide (O1LPS) as opsonins (p < 0.01 or < 0.05). Similar results were obtained with rabbit antiserum against a non-encapsulated isogenic strain. To further determine how salicylate increases susceptibility to phagocytosis, the binding of monoclonal antibodies against O1LPS or the LPS core and the binding of complement component C3b were measured by ELISA. The data indicate that salicylate reduced the barrier of CPS in serotypes O1:K1, O1:K10, and O1:K16 and unmasked subcapsular antigenic components in serotypes O1:K2 and O1:K66 so that bound opsonins could react with receptors on phagocytes. Serum bactericidal assays supported this conclusion. Therefore, decapsulating agents such as salicylate accentuate phagocytosis of K. pneumoniae by making subcapsular antigens and components accessible to immune and nonimmune host defences and vaccination with subcapsular antigens may exhibit optimal protection against lethal infection when combined with salicylate therapy.
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PMID:Salicylate-enhanced exposure of Klebsiella pneumoniae subcapsular components. 865 9


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