Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Muramic Acids”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed1976

Chemical structure of the peptidoglycan of Vibrio parahaemolyticus A55 with special reference to the extent of interpeptide cross-linking.

The chemical structure of the cell wall peptidoglycan of Vibrio parahaemolyticus A55 was studied. Estimation of cross linkages between peptide subunits in the peptidoglycan by dinitrophenylation showed that about 30% of the total 2,6-diaminopimelic acid (A2pm) residues were involved in cross linkages. The presence of interpeptide bridges was also demonstrated by isolating bisdisaccharide peptide subunit dimers from Chalaropsis muramidase digests of the cell wall peptidoglycan by gel filtration followed by ion-exchange column chromatography, although most of the building blocks obtained were uncross-linked disaccharide peptide monomers. The chain length of a glycan moiety of the peptidoglycan obtained by treatment with the L-11 enzyme and gel filtration of the digest was also studied. The chain length varied from 7 to 44, but 30% of the glycan fragments had muramic acid at the reducing end and a chain length of 28 to 44. In conformity with the above structural study it was demonstrated that a particulate enzyme fraction obtained by differential centrifugation of a sonicated preparation of V. parahaemolyticus catalyzed a penicillin-sensitive transpeptidation reaction, using UDP-MurNAc-14C-pentapeptide and UDP-GlcNAc as substrates.

Amino Acids↗
PubMed1977

Lack of peptidoglycan in the cell walls of Methanosarcina barkeri.

Neither muramic acid and glucosamine nor D-glutamic acid or other amino acids typical of peptidoglycan were found in cell walls of two strains of Methanosarcina barkeri. The main components are galactosamine, neutral sugars and uronic acids. Therefore, the structural component of the cell wall most likely consists of an acid heteropolysaccharide, resembling that of Halococcus morrhuae. It is, however, not sulfated.

Bacteria↗
PubMed1990

Simultaneous determination of neutral and amino sugars in biological materials.

A method is described for the simultaneous analysis of nine neutral and three amino sugars. Mixtures of standard sugars and biological samples were acid hydrolyzed with a two step Saeman procedure, neutralized with BaCO3, reduced with sodium borohydride, acidified, evaporated and alditol acetates prepared. Baseline resolution was achieved on a glass-capillary SP-2340 column in ca. 52 min. Reproducibility, response factors and hydrolysis losses were determined. Quantitation was linear over the range of 10-20 micrograms/ml to 2000 micrograms/ml. Conditions were defined for the reproducible quantitation of muramic acid.

Amino Sugars↗
PubMed2004

Identification of the namH gene, encoding the hydroxylase responsible for the N-glycolylation of the mycobacterial peptidoglycan.

The peptidoglycan of most bacteria consists of a repeating disaccharide unit of beta-1,4-linked N-acetylmuramic acid and N-acetylglucosamine. However, the muramic acid moieties of the mycobacterial peptidoglycan are N-glycolylated, not N-acetylated. This is a rare modification seen only in the peptidoglycan of mycobacteria and five other closely related genera of bacteria. The N-glycolylation of sialic acids is a unique carbohydrate modification that has been studied extensively in eukaryotes. However, the significance of the N-glycolylation of bacterial peptidoglycan is unknown. The goal of this project was to identify the gene encoding the hydroxylase responsible for the N-glycolylation of the mycobacterial peptidoglycan. We developed a novel assay for the mycobacterial UDP-N-acetylmuramic acid hydroxylation reaction and demonstrated that Mycobacterium smegmatis has an enzyme activity that can convert UDP-N-acetylmuramic acid to UDP-N-glycolylmuramic acid. We identified the gene namH encoding the mycobacterial UDP-N-acetylmuramic acid hydroxylase by computer data base searching and motif comparisons with the eukaryotic enzymes responsible for the N-glycolyation of sialic acids. The namH gene is not essential for in vitro growth as we were successful in deleting the gene in M. smegmatis. The M. smegmatis mutant is devoid of UDP-N-acetylmuramic acid hydroxylase activity and synthesizes only N-acetylated muropeptide precursors. Furthermore, the mutant exhibits increased susceptibility to beta-lactam antibiotics and lysozyme. Our studies suggest that the N-glycolylation of mycobacterial peptidoglycan may play a role in lysozyme resistance or may contribute to the structural stability of the cell wall architecture.

Amino Acid Sequence↗
PubMed1963

Location and composition of spore mucopeptide in Bacillus species.

Spore integuments of Bacillus coagulans were prepared containing nearly all the hexosamine and alpha, epsilon-diaminopimelic acid (DAP) present in intact spores. Subsequent autolytic action resulted in the destruction and removal of the residual cortical structure and "cortical membrane" leaving the appearance of the inner and outer spore coats unchanged in electron micrographs. Concurrently, all the hexosamine and DAP in the preparation was released mainly as non-diffusible mucopeptide containing alanine, glutamic acid, DAP, and all the glucosamine and muramic acid. Some diffusible peptides containing alanine, glutamic acid, and DAP were also present but there was little protein or carbohydrate. Lysozyme digestion of integument preparations from heated spores of Bacillus 636, B. subtilis, B. coagulans, and B. stearothermophilus specifically removed the residual cortex and cortical membrane with the release of the mucopeptide. In B. cereus T, only the residual cortex and part of the mucopeptide were solubilized by lysozyme. The effect of several reagents and enzymes upon the appearance and removal of hexosamine from B. coagul ans spore integuments is reported. The results show that spore mucopeptide is mainly located in the residual cortex and cortical membrane and suggest that these structures consist essentially of mucopeptide. The implications of these results in relation to the "contractile cortex" theory of heat resistance in spores are discussed.

Bacillus↗
PubMed1962

Isolation and properties of a surface antigen of Staphylococcus aureus.

A technique is described for the isolation and purification of an antigen released into the culture medium by Staphylococcus aureus strain Smith. The antigen was found to be homogeneous when examined by free electrophoresis and analytic ultracentrifugation. Immunologic homogeneity was established by immunoelectrophoresis and quantitative precipitin tests using high titer antiserum prepared against the homologous organism. Chemical analysis showed that the antigen contained 70 per cent carbohydrate, of which approximately 30 to 35 per cent was believed to be glucosamine. The analytic data suggested that another amino sugar, probably carboxylated, was also present, but extreme lability of this compound to mild hydrolytic procedures has thus far precluded further identification. The remainder of the antigen was composed of alanine, glutamic acid, aspartic acid, lysine, glycine, serine, and threonine. No muramic acid was found. The chemical and physical data indicate that the antigen described herein is a previously unrecognized component of Staphylococcus aureus. The purified compound was capable of absorbing agglutinating antibody from antiserum prepared against S. aureus Smith, indicating that it was a surface component of this encapsulated staphylococcus. It is proposed that the antigen be known as the Smith surface antigen (SSA). The injection of SSA into rabbits did not produce precipitating antibodies. However, SSA did precipitate at low concentrations (0.5 microg/ml) with antiserum prepared against S. aureus Smith and one other strain of S. aureus tested. Antiserum against two other aureus strains reacted only with high concentrations of SSA. SSA did not react with S. albus antiserum or with normal sera from several animal species. Experiments are in progress to define further the distribution of SSA. Intradermal injection of small quantities of SSA into rabbits immunized with S. aureus Smith evoked a reaction of cutaneous hypersensitivity, which was maximal in 8 to 12 hours. SSA appeared to be the substance responsible for the ability of S. aureus Smith to resist engulfment by phagocytes, since absorption of Smith antiserum with SSA effectively removed opsonizing antibodies. SSA induced protection in mice against experimental staphylococcal disease. The subcutaneous injection of 0.1 microg resulted in protection against a subsequent intraperitoneal challenge with 50 to 100 LD(50)'s of S. aureus Smith suspended in mucin. Increasing as well as decreasing the immunizing dose resulted in significantly less protection.

Animals↗
PubMed2000

Hongia gen. nov., a new genus of the order Actinomycetales.

An aerobic, nocardioform actinomycete, named LM 161T, was isolated from a soil sample obtained from a gold mine in Kongiu, Republic of Korea. This organism formed well-differentiated aerial and substrate mycelia and produced branched hyphae that fragmented into short or elongated rods. The cell wall contains major amounts of LL-diaminopimelic acid, alanine, glycine, glutamic acid, mannose, glucose, galactose, ribose and acetyl muramic acid. The major phospholipids of this isolate are phosphatidylcholine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol, and the major isoprenologue is a tetrahydrogenated menaquinone with nine isoprene units. The whole-cell hydrolysate of strain LM 161T contains 12-methyltetradecanoic and 14-methylpentadecanoic acids as the predominant fatty acids, but does not contain mycolic acids. The G+C content of the DNA is 71.3 mol%. The phylogenetic position of the test strain was investigated using an almost complete 16S rDNA sequence. The isolate formed the deepest branch in the clade encompassing the members of the suborder Propionibacterineae Rainey et al. 1997. On the basis of chemical, phenotypic and genealogical data, it is proposed that this isolate be classified within a new genus as Hongia koreensis gen. nov., sp. nov. in the order Actinomycetales. The type strain is LM 161T (= IMSNU 50530T).

Actinomycetales↗
PubMed2006

Millisia brevis gen. nov., sp. nov., an actinomycete isolated from activated sludge foam.

The taxonomic position of two mycolic-acid-producing actinomycetes, isolates J81T and J82, which were recovered from activated sludge foam, was clarified. Comparative 16S rRNA gene sequence studies indicated that the organisms formed a distinct lineage within the Corynebacterineae 16S rRNA gene tree. The taxonomic integrity of this group was underpinned by a wealth of phenotypic data, notably characteristic rudimentary right-angled branching. In addition, isolate J81T contained the following: meso-diaminopimelic acid, arabinose and galactose; N-glycolated muramic acid residues; a dihydrogenated menaquinone with eight isoprene units as the predominant isoprenologue; a fatty acid profile rich in oleic and palmitoleic acids and with relatively small proportions of myristic, stearic and tuberculostearic acids; mycolic acids with 44-52 carbons; and diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides as major polar lipids. Strain J81T was found to have a chemotaxonomic profile that serves to distinguish it from representatives of all of the other taxa classified as belonging to the suborder Corynebacterineae. In the light of these data, it is proposed that the two isolates be classified in a novel monospecific genus. The name proposed for this taxon is Millisia brevis gen. nov., sp. nov.; strain J81T (=DSM 44463T = NRRL B-24424T) is the type strain of Millisia brevis.

Actinobacteria↗
PubMed1976

Quantitative chemical analyses and antigenic properties of peptidoglycans from Clostridium botulinum and other clostridia.

The cell wall peptodoglycans were isolated from Clostridium botulinum and some other species of the genus Clostridium by hot formamide extraction and their quantitative chemical composition and antigenic properties were determined. The petidoglycan of C. botulinum type E was found to be a diaminopimelic acid (DAP)-containing type composed of glucosamine, muramic acid, glutamic acid, alanine and DAP in the molar ratio of 0.76:0.78:1.00:1.88:0.81. All other types of C. botulinum and Clostridium sporogenes also belonged to the same peptidoglycan type. The peptidoglycans of Clostridium bifermentans and Clostridium histoloyticum contained DAP but they differed from those of C. botulinum in the molar ratio of alanine to glutamic acid. The peptidoglycan of Clostridium perfringens was composed of glutamic acid, alanine, DAP and glycine in the molar ratio of 1.00:1.64:0.94:0.90. On the other hand, the peptidoglycan of Clostridium septicum was found to contain lysine instead of DAP and the molar ratio was 1.00:1.41:0.96 for glutamic acid, alanine and lysine. In spite of the difference in amino acid composition of peptidoglycans among the clostridia, the quantitative precipitin test demonstrated that antiserum against C. botulinum type E peptidoglycan cross-reacted with the peptidoglycans from other clostridia as well as various types of C. botulinum.

Alanine↗
PubMed1979

Chemical composition of Streptococcus mutans cell walls and their susceptibility to Flavobacterium L-11 enzyme.

The susceptibility to a cell wall lytic L-11 enzyme from Flavobacterium sp. and the quantitative and/or qualitative composition of the cell walls of some strains of cariogenic Streptococcus mutans and a non-cariogenic strain of Streptococcus mitis were determined. The purified cell walls of S. mutans strains HS-1 (serotype a), BHT (b), NCTC10449 (c), C67-1 (c), C67-25 (c), OMZ 176 (d), MT703 (e), MT557 (f), OMZ65 (g), and AHT (g), and S. mitis CHT contained glutamic acid, alanine, and lysine as well as muramic acid and glucosamine as a peptidoglycan component. Besides these amino acids, significant amounts of threonine were detected in strains HS-1, OMZ65, and AHT cell walls, and considerable amounts of aspartic acid and/or threonine as well as several other amino acids in OMZ176, OMZ65, and CHT cell walls. Rhamnose was a common special component of the cell walls of S. mutans strains BHT, NCTC10449, MT703, B2 (e), MT557, and AHT, and S. mitis CHT. An additional sugar component, glucose, was detected in the cell walls of all of these strains except BHT, and galactose was found in BHT, AHT, and CHT cell walls. Galactosamine was present in S. mitis CHT cell walls. Varying amounts of phosphorus were detected in the cell walls of all the strains examined. The cell walls of all these streptococcal strains except MT703, 6715, and AHT were susceptible to the lytic action of the L-11 enzyme to various extents. No consistent relationship was observed between the amino acid and sugar composition of these cell walls and their susceptibility to the L-11 enzyme. The chemical composition of these cell walls is discussed in terms of the serological classification of S. mutans.

Amino Acids↗
PubMed1976

Cell-wall lipopolysaccharide of the 'Shigella-like' Escherichia coli 0124. Structure of the polysaccharide chain.

From Escherichia coli 0124 two lipopolysaccharide preparations were obtained with phenol/water extraction and cetavlon precipitation. Polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate and chemical analysis showed that the two preparations from E. coli 0124 and the corresponding preparations from Shigella dysenteriae type 3 reacted alike. The O-specific polysaccharide moiety was characterized with proton magnetic resonance spectroscopy, optical rotation and paper electrophoresis. The constituents were determined by gas chromatography and ion-exchange chromatography. The polysaccharide contained glucose (Glc), galactose (Gal), galactosamine (GalN) and 4-O-(1'-carboxyethyl)-D-glucopyranose (glucolactilic acid, GlcLA) in the molar ratios of 1:2:1:1. Glucolactilic acid, which has a structure similar to muramic acid, was first found in Sh. dysenteriae. The polysaccharide from E. coli 0124 and oligosaccharides obtained from it by partial acid hydrolysis were subjected to methylation analysis using the method of combined gas chromatography--mass spectrometry. The results indicated that the pentasaccharide repeating unit of the polysaccharide is (see article). In the polysaccharide the repeating units are joined through galactofuranosidic linkages. This structure is identical with that of the somatic polysaccharide of Sh. dysenterae type 3.

Cell Wall↗
PubMed1972

Isolation, characterization, and ultrastructure of the peptidoglycan layer of a marine pseudomonad.

The peptidoglycan layer of a marine pseudomonad was observed by electron microscopy in thin sections of plasmolyzed intact cells and mureinoplasts but not in untreated intact cells. Only fragments of this layer could be isolated by sodium lauryl sulfate (SLS) treatment of mureinoplast envelopes. Sacculus-like peptidoglycan structures were obtained from growing cells by immediate heat inactivation of cellular autolytic enzymes and subsequent SLS, trypsin, and nuclease treatments. Recently, similar peptidoglycan sacculus-like structures have been obtained by adding SLS to the growing culture and treating the isolated particulate material with nucleases. Thin-sectioned and negatively stained preparations of whole cell peptidoglycan showed compressed profiles of cell-shaped sacculi. Peptidoglycan prepared by SLS treatment of mureinoplast envelopes had a similar composition to that prepared from whole cells. The major amino sugars and amino acids in the peptidoglycan component were glucosamine, muramic acid, alanine, glutamic acid and diaminopimelic acid in the molar ratios 1.18:1.24:1.77:1.00:0.79. Forty-five per cent of the epsilon-amino groups of diaminopimelic acid were cross-linked. The peptidoglycan was estimated to account for about 1% of the cell dry weight.

Amino Acids↗
PubMedDate not supplied

[Quantitative determination of the protein and carbohydrate polymers in the cell wall of Streptococcus group A].

The content of protein and carbohydrate polymers was estimated in the cell wall of Streptococcus, group A, type 29. A method was developed for analysing peptidoglycane in a polysaccharide-peptidoglycane complex after the prior oxidation by sodium periodate. It was found that the cell wall peptidoglycane bears two carbohydrate and three amino acid residues, i. e. N-acetylglucosamin, muramic acid, glutamic acid, alanine and lysine, in the ratio 1:1:1:4:1, respectively. The data on the cell wall composition prior to and after its oxidation with sodium periodate are given, and the ratio between the main structural components is determined: proteins (60% mol), polysaccharide (23% mol), peptidoglycane (17% mol).

Bacterial Proteins↗
PubMed1991

Induction of arthritis in rats by soluble peptidoglycan-polysaccharide complexes produced by human intestinal flora.

Peptidoglycan-polysaccharide complexes were isolated from feces of a healthy subject and from ileostomy fluid from 5 patients. Peptidoglycan-polysaccharide complexes were tested for arthritogenicity in a rat model, by subcutaneous injection in Freund's incomplete adjuvant. Complexes from the healthy subject did not induce arthritis, but those from ileostomy fluid of 1 of the patients induced severe, chronic joint inflammation. We concluded that peptidoglycan-polysaccharide complexes from intestinal flora are potentially arthritogenic in rats. This arthritogenicity may be influenced by the content of muramic acid and rhamnose in these complexes.

Adult↗
PubMed1980

Characterization of pneumococcal purpura-producing principle.

Purpura was grossly observable in albino mice 6 to 8 h after the intraperitoneal injection of sterile, deoxyribonuclease-treated, cell-free extracts prepared by sodium deoxycholate-induced lysis, sonic disruption, Parr bomb treatment, autolysis without sodium deoxycholate, or alternate freezing and thawing of washed suspensions of Streptococcus pneumoniae type I. Cell-free extracts obtained from sonically disrupted, heat-killed cells (100 degrees C for 20 min) did not contain purpurogenic activity. The reaction was maximal at approximately 24 h postinjection, started to fade slowly after 24 to 48 h, and usually was not grossly observable by 4 to 6 days postinjection. The purpura-producing principle (PPP) in the cell-free extract was purified by sequential ammonium sulfate precipitation, protamine sulfate precipitation, Sepharose 6B gel filtration, wheat germ lectin-Sepharose 6MB affinity chromatography, ribonuclease and trypsin treatment, and a second Sepharose 6B gel filtration step. The final preparation (i) contained glucosamine (5.6%), muramic acid (8.0%), neutral carbohydrate (12.8%), phosphate (8.0%), orcinol-reactive material (6.0%), and Lowry-reactive material (1.6%), and (ii) was free of detectable amounts of deoxyribonucleic acid, capsular polysaccharide, neuraminidase, cytolysin, and hyaluronidase. The isoelectric point and molecular size of the PPP were approximately pI 3.0 and several million daltons, respectively, and the activity remained in the supernatant fluid after centrifugation for 1 day at 105,000 x g. PPP activity was destroyed by incubation with egg white lysozyme and sodium metaperiodate but was resistant to trypsin, pronase, alpha-amylase, deoxyribonuclease, ribonuclease, alkaline phosphatase, pancreatic lipase, 7% trichloroacetic acid, 6 M urea, autoclaving (121 degrees C) for 30 min, and mild acid and alkali exposure. Our observations indicate that the PPP requires intact beta-1,4-glucosidic linkages for activity and support the working hypothesis that activity is associated with pneumococcal peptidoglycan solubilized by the bacterium's autolysin.

Animals↗
PubMed1986

Polysaccharide covalently linked to the peptidoglycan of the cyanobacterium Synechocystis sp. strain PCC6714.

A polysaccharide was found to be covalently linked to the peptidoglycan of the unicellular cyanobacterium Synechocystis sp. strain PCC6714 via phosphodiester bonds. It could be cleaved from the peptidoglycan-polysaccharide (PG-PS) complex by hydrofluoric acid (HF) treatment in the cold (48% HF, 0 degrees C, 48 h) yielding a pure, HF-insoluble peptidoglycan fraction and an HF-soluble polysaccharide fraction. The PG-PS complex was isolated from the Triton X-100-insoluble cell wall fraction by hot sodium dodecyl sulfate treatment and digestion with proteases. Digestion of the complex with N-acetylmuramidase released the glycopeptide-linked polysaccharide, which was further purified by dialysis and gel filtration on Sephadex G-50 and G-200. The polysaccharide consisted of glucosamine, mannosamine, galactosamine, mannose, and glucose and had a molecular weight of 25,000 to 30,000. Muramic acid-6-phosphate was identified as the binding site of the covalently linked, nonphosphorylated polysaccharide as revealed by chemical analysis of linkage fragments of the PG-PS complex.

Chemical Phenomena↗
PubMed1989

Effect of a soluble bacterial carbohydrate fraction on the viscosity of intestinal contents in healthy subjects and patients with Crohn's disease.

Supernatants of faecal suspensions from patients with Crohn's disease (CD) showed much lower viscosity than those from healthy subjects. Material responsible for the viscosity could be precipitated with ethanol. Gel filtration indicated that the viscosity was not due to the glycoprotein fraction but to a fraction with higher molecular weight and relatively high contents of muramic acid suggesting a bacterial origin. The concentration and viscosity of this fraction are less in faeces from patients with CD than in that of healthy subjects.

Adult↗
PubMed1975

Malakoplakia of the prostate: a morphological and biochemical study.

A case of malakoplakia of the prostate is presented. Electron microscopic appearances support the origin of the Michaelis-Gutmann bodies from phagolysosomes in the histiocytes characteristic of the lesion. Biochemical analysis revealed the presence of muramic acid in the prostate with malakoplakia. This amino sugar is characteristic of bacterial cell walls and despite the absence of demonstrable bacteria in the affected tissues indicates the involvement of bacteria in the disease process.

Chromatography, Thin Layer↗