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PubMed1985

Effects of aqueous and alcoholic povidone-iodine on spores of Bacillus subtilis.

Spores of Bacillus subtilis NCTC 10073 were examined for susceptibility to two proprietary brands of povidone-iodine: an aqueous solution, Betadine and an alcoholic solution, Videne. Spores were converted to ion-exchange (Ca, H) and coat-defective (SLS-, UME-, UMS-, UDT- and UDS-treated) forms. The resistance of these to povidone-iodine was compared and related to uptake. Effects on spore protoplasts and cortex in relation to hexosamine release were also examined. The degree of spore penetration and site of action of povidone-iodine is discussed.

Bacillus subtilis↗
PubMed2007

Characterization of extracellular polymers synthesized by tropical intertidal biofilm bacteria.

AIM: This study was performed to determine the potential of tropical intertidal biofilm bacteria as a source of novel exopolymers (EPS). METHODS AND RESULTS: A screening procedure was implemented to detect EPS-producing biofilm bacteria. Isolates MC3B-10 and MC6B-22, identified respectively as a Microbacterium species and Bacillus species by 16S rDNA and cellular fatty acids analyses, produced different EPS, as evidenced by colorimetric and gas chromatographic analyses. The polymer produced by isolate MC3B-10 displays significant surfactant activity, and may chelate calcium as evidenced by spectroscopic analysis. CONCLUSIONS: Polymer MC3B-10 appears to be a glycoprotein, while EPS MC6B-22 seems to be a true polysaccharide dominated by neutral sugars but with significant concentrations of uronic acids and hexosamines. EPS MC3B-10 possesses a higher surfactant activity than that of commercial surfactants, and given its anionic nature, may chelate cations thus proving useful in bioremediation. The chemical composition of polymer MC6B-22 suggests its potential biomedical application in tissue regeneration. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of a Microbacterium species producing EPS with surfactant properties, which expands our knowledge of the micro-organisms capable of producing these biomolecules. Furthermore, this work shows that tropical intertidal environments are a nonpreviously recognized habitat for bioprospecting EPS-producing bacteria, and that these molecules might be involved in ecological roles protecting the cells against dessication.

Bacillus↗
PubMed1977

Chemical analysis of an angiofibroma from a patient with tuberous sclerosis.

Amino-acid analyses on the acid hydrolysates of an angiofibroma and skin established that the former tissue contained less collagen than skin based on the reduced content of hydroxyproline, glycine, proline and alanine in the tumour. From lysosomal enzyme measurements it became evident that the specific activities of the hexosaminidases, beta-glucuronidase and beta-galactosidase were elevated. Analyses of the alcohol insoluble fraction following pronase digestion revealed that the tumour contained more acidic glycosaminoglycan (AG) than skin as assessed by uronic acid and hexosamine measurements. More outstanding, however, was the seven-fold increase in the total carbohydrate in the AG fraction of the tumour. The overall composition of this fraction was very similar to comparable material from foetal skin except that the tumour fraction contained increased sulphate concentration.

Adult↗
PubMed1982

Biochemical and allergenic properties of the house dust mite extract, Dermatophagoides pteronyssinus.

A further study has been made on the house dust mite extract, Dermatophagoides pteronyssinus, with emphasis on gel-filtrated fraction 2 (F2). The crude mite extract showed at least nine discs on polyacrylamide disc electrophoresis and contained less than 0.25% sialic acid and less than 0.5 mM hexosamine and no detectable uronic acid. From gel filtration of the crude extract a No 2 fraction (F2) with allergenic activity showed at least five components on SDS disc electrophoresis covering a molecular weight range of between 15,000 and 70,000. The major allergenic activity of F2 dissolved in pH 7-8 and 4-5 on an isoelectric focusing column. Affinity chromatography and lectins showed that allergenic activity did not relate to structures of N-acetyl-D-glucosamine or N-acetyl-D-galactosamine. Allergenic activity of the crude extract was no affected by peptic digestion and the mite digest prepared by trypsin and pronase showed a similar fractionation and activity profile as crude extract.

Allergens↗
PubMed1977

Chemical studies on a hamster sublingual glycoprotein.

A secretory glycoprotein was isolated from the hamster sublingual gland. It contains 65% carbohydrates, the remainder being protein. The principal type of sialic acid was identified as N-acetylneuraminic acid with about 1/4 of the molecules O-acetylated. The hexosamine occurs mainly as N-acetylgalactosamine; other sugars present are galactose and fucose. The carbohydrate side chains are linked to the protein core by an O-glycosyl linkage between seryl and threonyl residues and N-acetylgalactosamine. The glycoprotein has an apparent molecular weight of 330,000. The sialogly coprotein may act as a biological antifreeze. Relevant differences in the chemical composition of the secretory glycoproteins of the sublingual and submaxillary salivary glands of this species are briefly discussed.

Amino Acids↗
PubMed1977

The molecular components of human transferrin type C.

Immunologically pure human transferrin type C (TfC) was isolated from the plasmas of 11 individual healthy donors. After conversion into the 2Fe-form, the preparations were analysed by polyacrylamide gel electrophoresis and chromatography on DEAE-cellulose. In all samples studied by either method the presence of three components, designated A, B and C, was observed. Calculations from eight chromatograms yielded the following relative proportions for the components: A:6%, B:62% and C:32%. The quantity of iron bound played no role in this chromatographic resolution. The components were immunologically identical but their sialic acid content increased inthe order of A less than B less than C. The presence of galactose as an ultimate residue of the oligosaccharide chains in TfC component A was confirmed by a biological test. This observation together with the results of earlier analyses for hexose, hexosamine and galactose in the subfractions from Behringwerke human transferrin, suggests that sialic acid is probably the only variable among TfC components A, B and C. Loss of sialic acid from component C during the isolation of TfC was excluded as an explanation for the presence of the other two components. The electrophoretic appearance of TfC samples from five patients with liver disease (chronic active hepatitis, cirrhosis or alcoholic liver) did not noticeably differ from that of TfC FROM HEALTHY PERSONS. Baboon transferrin resembles TfC with respect to sialic acid heterogeneity. This species was therefore studied to decide whether sialic acid is gradually lost from transferrin in the circulation or whether transferrin is not fully sialylated before discharge from the hepatocyte. Using DEAE-cellulose chromatography no difference was found between baboon transferrin molecules which were less than 6h old and those which had a mean age of 8.9 days. By inference it is suggested that the reason for the multiplicity of TfC is also likely to be biosynthetic.

Adult↗
PubMed1989

Chemical characterization and biologic properties of lipopolysaccharide from Bacteroides gingivalis strains W50, W83, and ATCC 33277.

The chemistry and selected biological activity of lipopolysaccharide (LPS) from Bacteroides gingivalis strains W50, W83, and ATCC 33277 were compared, as well as the role of this molecule as a mediator of selected inflammatory responses. Chemically, the LPSs consisted of 47-58% Lipid A, 5-10% carbohydrate, 0.05% 3-deoxy 2-octulosonic acid, 0.3% heptose, 3.8-5.2% hexosamine, and 2% phosphate. Rhamnose represented the dominant sugar (26-36%), with lesser amounts of glucose (18-34%), galactose (18-25%), mannose (9-12%), glucosamine (7-11%), and galactosamine (2-5%). The major fatty acids were: 13-methyl-tetradecanoate (42-45%), 3-OH-heptadecanoate (21-23%), hexadecanoate (16-19%), and 12-methyl-tetradecanoate (6-8%). SDS-PAGE and sodium deoxycholate-PAGE revealed the LPS to be a smooth chemotype. Differences in migration patterns between the virulent and avirulent strain LPSs also occurred. C3H/HeN macrophages (Mø) exposed to 1 microgram/ml of LPS released 3.2-4.2 ng of prostaglandin E (PGE)/ml of supernatant, representing 236-278% of control. Interleukin-1 (IL-1) activity in C3H/HeN and C3H/HeJ Mø exposed to 50 micrograms of LPS/ml was 382-724% and 270-300% of control, respectively; similar Mø exposed to 10 micrograms of LPS/ml released 1.6-2.0 ng and 0.3-0.5 ng of tumor necrosis factor (TNF)/ml of supernatant, respectively. Maximum TNF release in C3H/HeN Mø occurred in response to 50 micrograms of LPS/ml, and was sustained for up to 96 hours. These results suggest that LPS from the B. gingivalis strains stimulate cytokine production from Mø which, in turn, may play a role in orchestrating the inflammatory response for the development of periodontal diseases.

Bacterial Outer Membrane Proteins↗
PubMed1990

Isolation and characterization of lipopolysaccharide from Centipeda periodontii ATCC 35019.

Lipopolysaccharide (LPS) was extracted from cells of Centipeda periodontii ATCC 35019 by a hot phenol-water method, purified by nuclease treatment and by repeated ultracentrifugations. The LPS was composed of 21.7% hexose, 9.1% hexosamine, 10.3% fatty acid, 0.5% protein, 2.5% phosphorus, 4.3% 2-keto-3-deoxyoctonate(KDO) and 2.3% heptose. The major fatty acids of the LPS were 3OH C13:0 and C13:0. C. periodontii LPS was able to gelatinize Limulus amebocyte and to produce the local Schwartzman reaction in rabbits. LPS from C. periodontii exhibited strong immunobiological activities, mitogenicity on splenocytes of C3H/HeN mice, and stimulation of interleukin 1 (IL-1) production in peritoneal macrophages of C3H/HeN mice.

Endotoxins↗
PubMed1983

Glycoprotein metabolism in rat colonic epithelial cell populations with different proliferative activities.

Epithelial cells with different proliferative activities were isolated from rat proximal and distal colon. The distribution of fucose, hexose, hexosamine, and sialic acid as well as the activities of three glycosyltransferases, eight glycosidases, and a nucleotide sugar pyrophosphatase, enzymes involved in glycoprotein metabolism, were then examined in these cells. The results of the present study demonstrate that: (1) all proximal cell populations appear to possess a higher content of hexose, fucose, and sialic acid than their distal counterparts; (2) in general, the proximal colonic populations have higher glycosyltransferase but similar glycosidase activities than their distal counterparts; (3) proliferative cells in both colonic regions have greater glycosyltransferase and glycosidase activities than non-proliferative cells, although their carbohydrate content is similar. These findings suggest that alterations in glycoprotein metabolism exist during differentiation along the length of the rat colon. Furthermore, these data indicate that certain enzymes involved in glycoprotein metabolism may serve as markers for cellular differentiation in this organ.

Animals↗
PubMed1976

Interference of nucleoside diphosphate derivatives of 2-deoxy-D-glucose with the glycosylation of virus-specific glycoproteins in vivo.

The predominant effect of 2-deoxy-D-glucose on chick embryo cells infected with Semliki Forest virus is an interference with glycosylation of virus-specific glycoproteins; this results in a block of synthesis of infectious virus. Incorporation of radioactive mannose is blocked severely in the presence of 2-deoxyglucose in the cultural medium although it is readily phosphorylated and subsequently activated by GTP to yield GDP-mannose, which accumulates under these conditions. The intracellular concentrations of GDP-mannose and UDP-N-acetyl-D-hexosamine are not reduced in the presence of the inhibitor. An equimolar concentration of mannose in the cultural medium competes with the inhibitory effect of the deoxysugar and drops the cellular pool of GDP-2-deoxy-D-glucose below the level of detection, at the same time restoring the synthesis of infectious virus. When the intracellular concentration of UDP-2-deoxyglucose is reduced by addition of glucose into the cultural medium the inhibition of virus synthesis by the deoxysugar and the concentration of GDP-2-deoxyglucose within the cells remain near to the values when the inhibitor is present alone. It is concluded that among the metabolites of 2-deoxyglucose which occur in vivo after addition of 2-deoxyglucose to the culture medium, GDP-2-deoxyglucose is the agent responsible for inhibition of glycosylation of viral glycoproteins.

Animals↗
PubMed1979

Crystallization and properties of cathepsin B from rat liver.

Cathepsin B from rat liver was purified to apparent homogeneity by cell-fractionation, freezing and thawing, acetone treatment, gel filtration, DEAE-Sephadex and CM-Sephadex column chromatography, and was crystallized. The purified enzyme formed spindle-shaped crystals and its homogeneity was proved by disc gel electrophoresis in the presence of sodium dodecyl sulfate and by ultracentrifugal analysis. Its s20,w value was 2.8 S and its relative molecular mass was calculated to be 22,500 (+/- 900) by sedimentation equilibrium analysis. Crystalline cathepsin B was shown to consist of four isozymes with isoelectric points between pH 4.9 and 5.3, the main isozyme having an isoelectric point of pH 5.0. The enzyme was irreversibly inactivated by exposure to weak alkali. The pH optimum was 6.0 with alpha-N-benzoyl-DL-arginine-4-nitroanilide as substrate. Amino acid analysis showed that the enzyme contained hexosamine, glucosamine and galactosamine. Cathepsin B inactivated aldolase, glucokinase, apo-ornithine aminotransferase, and apo-cystathionase, but the rates of inactivation of glucokinase, apo-ornithine aminotransferase, and apocystathionase were lower than that of aldolase. Studies by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate showed that cathepsin B degraded apo-ornithine aminotransferase to two polypeptide chains differing in relative molecular mass and electrophoretic mobility.

Amino Acids↗
PubMed1979

Characterization of porins from the outer membrane of Salmonella typhimurium. 1. Chemical analysis.

The three species of channel-forming outer membrane proteins, porins, have been purified to homogeneity from mutant strains of Salmonella typhimurium which produce single species of porin. Purification was by stepwise solubilization with dodecylsulfate or guanidine thiocyanate, gel filtration, and preparative gel electrophoresis. Amino acid compositions and tryptic peptide maps of the three species of porins showed close resemblance, but at the same time clear differences among them. The number of amino acid residues in the porins purified from the strains SH5551, SH6377 and SH6017 were 361, 354 and 345, and their calculated molecular weights 39800, 39300 and 38000, respectively. Amino-terminal and carboxyl-terminal amino acids in all three species of porins appeared to be alanine and phenylalanine, respectively. Neither half-cystine nor hexosamine was found in these preparation of porins. The isoelectric points of porins from the strains SH5551, SH6377 and SH6017, determined by isoelectric focusing, showed slight differences from each other. These results, and the genetic experiments from another laboratory, suggest that the three species of porins in Salmonella typhimurium are distinct polypeptides, probably coded for by distinct structural genes, which might have been derived from the same ancestral gene.

Amino Acids↗
PubMed1981

The physicochemical properties of the galactose-specific lectin from Momordica charantia.

A lectin has been isolated from Momordica charantia seeds and purified to homogeneity by affinity adsorption on a cross-linked arabinogalactan column and subsequent elution with 0.1 M lactose. In sedimentation velocity experiments an S20,W(O) degrees value of 6.5 S was obtained for the native lectin and 2.7 S for its subunits obtained by dissociation with 0.1% sodium dodecyl sulphate in the presence of 0.1% 2-mercaptoethanol. This lectin has a molecular weight of 120 000, is tetrameric in nature with two pairs of non-identical subunits of molecular weights 28 000 and 30 000. It is a glycoprotein containing 10% hexoses (2% glucose and 8% mannose) and 2.5% hexosamine, all glucosamine. It has two binding sites per molecule and has Ka values of 4.1 X 10(4) M-1 and 1.8 X 10(4) M-1 at 5 degrees C and 25 degrees C respectively for p-nitrophenyl beta-D-galactopyranoside with delta H degrees and delta S degrees values of --28.3 kJ mol-1 and --12.3J mol-1 K-1 respectively. Hemagglutinating activity of M. charantia lectin is inhibited by galactose and other carbohydrates containing the galactopyranosyl residue. From the chemical modification studies tryptophan and tyrosine residues are found to be important for the carbohydrate binding activity of M. charantia lectin.

Binding Sites↗
PubMed1981

Glycosaminoglycan biosynthesis in arterial wall. Sulfation of heparan sulfate in cell membrane of aortic media-intima.

Incubation of microsomal fractions with labelled 3'-phosphoadenylyl sulfate results in incorporation of [35S]sulfate into endogenous glycosaminoglycans. Specific radioactivity observed incorporated into heparan sulfate chains is 10-fold greater than that incorporated into chondroïtin sulfate chains. This is in agreement with the results obtained for glycosylation of glycosaminoglycans in arterial wall membrane fractions. Sulfation of heparan sulfate was studied since it contains N- and O-sulfate groups in contrast with the other sulfated glycosaminoglycans which contain only O-sulfate groups. Sulfation of heparan sulfate occurs rapidly, since sulfate incorporation is detected after exposure for only 0.5 min. Heparan sulfate was identified on the basis of its resistance to hyaluronidase and chondroïtin ABC lyase, its susceptibility to heparitinase, its sensitivity to nitrous acid and the presence of glucosamine as the only hexosamine. The chemical composition of the purified heparan sulfate fractions provides evidence for the high degree of sulfation of its chains. Studies into the distribution of sulfate residues on heparan sulfate at different times of sulfation indicate that N-sulfate groups are not randomly introduced into the polymer. The relationship between the processes of N- and O-sulfation was studied. The present results demonstrate that preferential N-sulfation is obtained for incorporation of labelled precursor over a short period, the O-sulfation occurring on previously N-sulfated heparan sulfate.

Animals↗
PubMed1983

Structural elements of methanopterin, a novel pterin present in Methanobacterium thermoautotrophicum.

During short-time labeling experiments, cells of Methanobacterium thermoautotrophicum incorporate a substantial part of 14CO2 in a yellow fluorescent compound (called YFC) [Daniels, L. & Zeikus, J. G. (1978) J. Bacteriol. 136, 75-84]. As the compound was present only in small amounts, its more abundant, metabolic precursor was identified, extracted and purified by column chromatography. The chromophore of this compound is 2-amino-4-hydroxypteridine (pterin) as indicated by its ultraviolet-visible-light absorption and fluorescence properties. Decomposition studies revealed the presence of a number of structural elements, viz. glutamic acid, phosphate and a hexosamine. 1H-NMR and 13C-NMR spectra pointed to the presence of additional, as yet unidentified, elements. The compound is a complex, novel pterin derivative, which we have called methanopterin.

Chemical Phenomena↗
PubMed1983

A novel one-carbon carrier (carboxy-5,6,7,8-tetrahydromethanopterin) isolated from Methanobacterium thermoautotrophicum and derived from methanopterin.

During short-term labeling experiments, cells of Methanobacterium thermoautotrophicum incorporated a substantial part of 14CO2 in a compound with a bright yellow fluorescence on dry thin-layer chromatography plates and called yellow fluorescent compound (YFC) [Daniels, L. and Zeikus, J.G. (1978) J. Bacteriol. 136, 75-84]. This compound was extracted and purified by ion-exchange column chromatography with formic acid gradients up to 0.3 M. Out of 325 g wet cells of M. thermoautotrophicum about 4 mg of the compound were isolated. This material and some degradation products obtained from it were studied by means of chemical decomposition, ultraviolet-visible-light spectroscopy and preliminary 1H-NMR spectroscopy. It has structural elements in common with methanopterin (see preceding paper in this journal); these elements are a pterin group, glutamate, a hexosamine. The pterin in this compound is present in a reduced form, presumably as 5,6,7,8-tetrahydromethanopterin, and the additional one-carbon unit is probably present as a carboxy group. Probably the first step of methanogenesis implies a carboxylation of methanopterin and a concomitant reduction of the pterin. The trivial name carboxy-5,6,7,8-tetrahydromethanopterin is introduced for the compound.

Carbon↗
PubMed1985

Comparative structural and lectin-binding studies on gamma-glutamyltransferase from human adult liver, fetal liver and primary hepatoma.

gamma-Glutamyltransferase was purified to apparent homogeneity from human adult liver, fetal liver and hepatoma by deoxycholate extraction, immunoaffinity chromatography, papain digestion, phenyl-Sepharose chromatography and preparative polyacrylamide gel electrophoresis. The purified enzyme from all three sources had an apparent Mr of 82 000 by Sephadex G-150 gel filtration and on dodecyl sulphate/polyacrylamide gel electrophoresis two nonidentical subunits of Mr 57 000 and 23 000 were obtained. The pI of all three forms was 3.85 and after neuraminidase treatment they each gave at least five bands with pI values ranging over 5.9-6.6. Sialic acid content was 188 (adult liver), 182 (fetal liver) and 188 (hepatoma) nmol/mg protein. Total neutral sugar content was 702 (adult and fetal liver) and 700 (hepatoma) nmol/mg protein. The hexosamine content of the enzyme from all the three sources was the same (354 nmol/mg protein) and galactosamine was absent. Partially purified hydrophobic and hydrophilic forms of gamma-glutamyltransferase from all the three sources were precipitated by Concanavalin A, Ricinus communis agglutinin and wheat germ agglutinin. These results show that gamma-glutamyltransferase from human adult liver, fetal liver and hepatoma are structurally similar and that the elevated levels found in fetuses and hepatoma are only a quantitative increase and are not due to a new isoenzyme.

Carbohydrates↗
PubMed1990

N-acetyl-L-galactosaminuronic acid as an epitope common to the O-polysaccharides of Pseudomonas aeruginosa serotype A and H (Homma) recognized by a protective human monoclonal antibody.

We have established a human--mouse heterohybridoma cell line producing a human monoclonal antibody TS-3G2 (IgG gamma 1, K). This monoclonal antibody specifically bound to O-polysaccharides belonging to plural Pseudomonas aeruginosa Homma serotypes, A and H, in contrast to serotype-specific monoclonal antibody which exclusively bound to strains belonging to a single specific serotype. The binding affinity for serotype A strains was higher than that for serotype H strains. Competitive enzyme immunoassay experiments with O-polysaccharide preparations derived from IID 1001, NCTC 8505 (serotype A) and IID 1009 (serotype H) and their derivatives demonstrated that the N-acetyl-L-galactosaminuronic acid residue in O-polysaccharide was essentially involved in the epitope for TS-3G2. Furthermore, a 6-deoxy-hexosamine residue neighboring the reducing terminal of N-acetyl-L-galactosaminuronic acid residues was also concerned with the epitope to some extent. In the experimental infection model of normal mice, the monoclonal antibody TS-3G2 showed a protective activity against both strains of serotype A and H.

Animals↗