Studies on the Pseudomonas aeruginosa PAO1 bacteriophage receptors

Receptor for phage PIK specific for Pseudomonas aeruginosa strain PAO1 was studied. Phage PIK was strongly inactivated by lipopolysaccharide (LPS) in vitro, exhibiting a PhI50 of 4.8 micrograms/ml. Further it was noted that this inactivation by LPS was reduced to 50% by several mono- and disaccharides when tested in vitro. D-glucosamine, D-mannose and L-rhamnose were found to be most effective at the concentration of 0.045 M, 0.25 M and 0.35 M respectively. This suggests the possibility that phage PIK receptor in LPS contains D-mannose, L-rhamnose and D-glucosamine. Either one of the former two could be located at a terminal position alpha-linked to the adjacent residue or located internally in the polysaccharide chain linked through its C-4 position. A theoretical approach to the interpretation of phage cell interaction was also investigated.     

Synthesis of Lewis A trisaccharide analogues in which D-glucose and L-rhamnose replace D-galactose and L-fucose, respectively

In our effort to design a safe anti-cancer vaccine based on the tumor associated carbohydrate antigen Le(a)Le(x), we are studying the cross-reactivity between the Le(a) natural trisaccharide antigen and analogues in which the L-fucose, D-galactose, and/or D-glucosamine residues are replaced by L-rhamnose or D-glucose, respectively. We describe here the chemical synthesis of two such Le(a) trisaccharide analogues. In one trisaccharide, D-glucose replaces D-galactose and in the second analogue L-rhamnose and D-glucose replace L-fucose and D-galactose, respectively. Introduction of the rhamnose and fucose moiety onto the poorly reactive 4-OH group of the N-acetylglucosamine residue in a disaccharide acceptor was successful after bis-N-acetylation of the amine group. These analogues will be used in competitive binding experiments with anti-Le(a) antibodies and their solution conformations will be studied.     

L-Rhamnose utilisation in Salmonella typhimurium

A khy , M.T., B rown , C.M. & O ld , D.C. 1984. L-Rhamnose utilisation in Salmonella typhimurium. Journal of Applied Bacteriology 56 , 269–274.
L-Rhamnose is degraded by strains of Salmonella typhimurium by isomerisation to L-rhamnulose, phosphorylation to L-rhamnulose-1-phosphate and cleavage to lac-taldehyde and dihydroxyacetone phosphate. The enzymes involved are, respectively, rhamnose isomerase (Rhal), rhamnulokinase (RhuK) and an aldolase (Ald). Strains able to grow rapidly on L-rhamnose contained a high-affinity uptake system for ³H-L-rhamnose that was induced by L-rhamnose and repressed by D-glucose. The synthesis of Rhal and RhuK was also induced by L-rhamnose but was not repressed by D-glucose. The synthesis of Ald was constitutive. Data are presented on some strains which grow very slowly on L-rhamnose and on others which do not utilise it.     

The 13C-N.M.R. spectra of disaccharides of D-glucose, D-galactose, and L-rhamnose as models for immunological polysaccharides.

Complete assignments of the 13C-n.m.r. spectra of disaccharides having beta-glycosidic linkages are presented and discussed. The disaccharides of D-glucose, D-galactose, L-rhamnose, 2-acetamido-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-galactose are model compounds for 13C-n.m.r. studies of immunological polysaccharides. Changing the nature of the reducing glucopyranose rings (D-glucose to L-rhamnose) has no important influence on the chemical shifts of the carbons of the non-reducing glucopyranose ring (D-glucose). The converse is also true: the chemical shifts of the carbons of the reducing glucopyranose ring (L-rhamnose) are not noticeably affected by a change of the non-reducing unit (D-glucose to D-galactose or 2-acetamido-2-deoxy-D-glucose).     

Carbon assimilation and taxonomic study of Bacillus subtillis and B. licheniformis]

All 14 strains of B. subtilis can use the following 17 sources of carbon and energy: D-glucose, D-mannose, D-glucosamine, salicin, D-ribose, maltose, sucrose, cellobiose, trehalose, arbutin, starch, mannitol, glycerol, glycerate, pyruvate, fumarate, and L-proline. All 15 strains of B. licheniformis can use the following 41 sources of carbon and energy: D-glucose, D-galactose, D-mannose, D-fructose, D-glucosamine, alpha-methyl-D-glucoside, beta-methyl-D-glucoside, salicin, D-gluconate, saccharate, D-xylose, L-arabinose, L-rhamnose, D-ribose, maltose, sucrose, cellobiose, melibiose, trehalose, arbutin, raffinose, starch, inulin, mannitol, D-sorbitol, glycerol, glycerate, citrate, L-malate, D-malate, mucate, pyruvate, fumarate, alpha-L-alanine, alpha-D-alanine, asparagine, L-glutamate, L-arginine, DL-ornithine, L-proline, and 4-amino-n-butyrate. The 29 strains form two distinct groups. Group A includes the 15 strains of B. licheniformis and 2 strains of B. subtilis; group B is formed of 11 strains of B. subtilis; the remaining strain of B. subtilis belongs to neither group. Bacillus licheniformis is a more homogeneous species than B. subtilis. The percentage of guanine + cytosine in the DNA of all 29 strains was determined. In the 14 strains of B. subtilis the average is 46.3% +/- 1.5. In the 15 strains of B. licheniformis the average is 46.4% +/- 0.9.     

Capsular polysaccharides and lipopolysaccharides from two Bacteroides fragilis reference strains: chemical and immunochemical characterization.

Fermentor growth of Bacteroides fragilis under controlled conditions in a complex medium containing 1% glucose and 10% fetal calf serum resulted in high yields of bacteria. After hot phenol-water extraction of the organisms, capsular polysaccharide was isolated from the aqueous phase and purified by Sephacryl S-300 chromatography in a buffer with 3% sodium deoxycholate. Lipopolysaccharide was isolated by phenol-chloroform-light petroleum ether extraction. The capsular polysaccharide from B. fragilis strain NCTC 9343 contained six sugars: L-fucose, D-galactose, D- and L-quinovosamine, D-glucosamine, and galacturonic acid. The capsule of strain ATCC 23745 also contained D-glucose, L-fucosamine, L-rhamnosamine, and a 3-amino-3,6-dideoxyhexose but lacked D-quinovosamine. The latter capsule also contained alanine (4%). The capsular polysaccharides were different immunochemically by ELISA inhibition. The lipopolysaccharide of both strains contained the same sugars (L-rhamnose, D-glucose, D-galactose, and D-glucosamine) and fatty acids (13-methyl-tetradecanoic and 3-hydroxy-hexadecanoic and 3-hydroxy-15 methyl-hexadecanoic as major constituents) and were identical by ELISA inhibition.     

Chemotaxis in Spirochaeta aurantia.

Cell of Spirochaeta aurantia M1 suspended in isotropic buffer solution swam in nearly straight lines and appeared to spin around their longitudinal axis. Occasionally, cells stopped and flexed, and then resumed translational motility, usually in a different direction. The average cell velocity was 26 micron/s. A quantitative assay for chemotaxis was used to test various chemicals for their ability to attract S. aurantia M1. The cells exhibited a tactic response toward 5 X 10(-2) M D-glucose between 10 and 35degree C; the optimum response was at 25degree C. At 5 degree C motility was not impaired, but D-glucose taxis was abolished. Chemotaxis toward D-glucose was stimulated by L-cysteine (2 X 10(-4) M). D-Glucose, 2-deoxy-D-glucose, alpha-methyl-D-glucoside, D-galactose, D-fucose, D-mannose, D-fructose, D-xylose, maltose, cellobiose, and D-glucosamine were effectve attractants for S. aurantia M1. D-Galactose taxis and D-fucose taxis were induced by the presence of D-galactose in the growth medium. The amino acids tested did not serve as attractants, tgrowing cells of S. aurantia M1 exhibited an aerotactic response.     

Characterization of some O-acetylated saponins from Quillaja saponaria Molina

Sixteen saponins were identified from a bark extract of Quillaja saponaria Molina. The compounds were characterized, using NMR spectroscopy, mass spectrometry and monosaccharide analysis, as quillaic acid substituted at C-3 with oligosaccharides consisting of a disaccharide, beta-D-Galp-(1-->2)-beta-D-GlcpA substituted with either D-xylose or L-rhamnose and at C-28 with complex oligosaccharide structures consisting of a disaccharide, alpha-L-Rhap-(1-->2)-4-O-acetyl-beta-D-Fucp, substituted with various amount of D-xylose. D-glucose, D-apiose, and L-rhamnose.     

Induction and catabolite repression of L-rhamnose dehydrogenase in Pullularia pullulans.

The growth of Pullularia pullulans on L-rhamnose (6-deoxy-L-mannose) as the sole carbon source induces the synthesis of L-rhamnose dehydrogenase, a nicotinamide adenine dinucleotide-dependent enzyme that catalyzes the oxidation of the deoxy sugar to L-rhamnonolactone. The enzyme induction is inhibited by cycloheximide, suggesting de novo synthesis. The presence of d-glucose (0.2%) or D-galactose (0.2%) simultaneously with the inducer in the induction medium produced 50% repression of dehydrogenase synthesis, but no effect was detected with D-fructose and D-mannose at the same concentration. High levels of D-glucose (2%), under maximal catabolite repression conditions, produced a complete inhibition of enzyme synthesis.     

Structural studies on the specific type VII pneumococcal polysaccharide

The specific type VII pneumococcal polysaccharide was isolated from the crude capsular material by precipitative and chromatographic methods. It contained D-galactose, D-glucose, L-rhamnose, 2-acetamido-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-galactose in the molar ratio of 3.5:2.3:3.0:2.1:1.0. Some of its structural features were revealed by methylation studies, time-lapse hydrolysis, periodate oxidation, and enzymic hydrolysis. The polysaccharide is branched at residues of D-galactose and 2-acetamido-2-deoxy-D-galactose. Non-reducing end groups consisted of D-galactopyranose and 2-acetamido-2-deoxy-D-glucopyranose residues, with the former predominating. Major components of the linear chains were (1→3)-linked L-rhamnose and (1→4)-linked D-glucose; the minor ones were (1→2)-linked L-rhamnose, (1→6)-linked D-galactose, and (1→6)-linked 2-acetamido-2-deoxy-D-glucopyranose. The (1→4)-linked D-glucose components may be present as cellobiose residues. The results are in accord with structural features deduced from the serological cross-reactivity of this polysaccharide.     

Lipopolysaccharides from Mesorhizobium huakuii and Mesorhizobium ciceri: chemical and immunological comparative data

Lipopolysaccharides of two Mesorhizobium species of different host specificity were compared: M. huakuii and M. ciceri. M. huakuii sp. was represented by five strains with special consideration of M. huakuii IFO 15243(T). SDS/PAGE profiles revealed that all M. huakuii LPS preparations contained low molecular mass fractions (LPS-II) of the same molecular size. All of lipopolysaccharides contained high molecular mass fractions (LPS-I). However, the high molecular mass fraction from each strain possessed an individual molecular size distribution pattern. The crossreactivity of blotted lipopolysaccharides with rabbit polyclonal antibodies against Mesorhizobium huakuii IFO 15243(T) whole bacteria indicated the presence of common epitope(s) within the investigated Mesorhizobium huakuii strains. Moreover, LPS from M. huakuii S52 also reacted with anti M. ciceri HAMBI 1750 serum showing that there are epitopes common for different mesorhizobial species. LPS isolated from Mesorhizobium huakuii strain IFO 15243(T) contained neutral sugars: L-6-deoxytalose, L-rhamnose, D-galactose and D-glucose, aminosugars:D-quinovosamine, D-glucosamine, D-2,3-diamino-2,3-dideoxyglucose and D-galacturonic and D-glucuronic acids. In the LPS preparation, fatty acids typical for Mesorhizobium strains were detected. 3-Hydroxydodecanoic, 3-hydroxy-iso-tridecanoic, 3-hydroxyeicosanoic, 3-hydroxyheneicosanoic and 3-hydroxydocosenoic acids were the major amide linked fatty acids, while iso -heptadecanoic, eicosanoic, docosenoic, as well as 27-hydroxyoctacosanoic and 27-oxooctacosanoic acids were the dominant ester linked fatty residues.     

L-Rhamnose utilisation in Salmonella typhimurium

L-Rhamnose is degraded by strains of Salmonella typhimurium by isomerisation to L- rhamnulose , phosphorylation to L- rhamnulose -1-phosphate and cleavage to lactaldehyde and dihydroxyacetone phosphate. The enzymes involved are, respectively, rhamnose isomerase ( RhaI ), rhamnulokinase ( RhuK ) and an aldolase (Ald). Strains able to grow rapidly on L-rhamnose contained a high-affinity uptake system for 3H-L-rhamnose that was induced by L-rhamnose and repressed by D-glucose. The synthesis of RhaI and RhuK was also induced by L-rhamnose but was not repressed by D-glucose. The synthesis of Ald was constitutive. Data are presented on some strains which grow very slowly on L-rhamnose and on others which do not utilise it.     

Synthetic reaction of Cellvibrio gilvus cellobiose phosphorylase.

The synthetic reactions of the cellobiose phosphorylase from Cellvibrio gilvus were investigated in detail. It was found that, besides D-glucose, some sugars having substitution or deletion of the hydroxyl group at C2 or C6 of the D-glucose molecule could serve as a glucosyl acceptor, though less effectively than D-glucose. The enzyme showed higher activity with beta-D-glucose than with the alpha-anomer as an acceptor. This result indicates that it recognizes the anomeric hydroxyl group not involved directly in the reaction. beta-D-Cellobiose was also phosphorolyzed faster than the alpha-anomer. Substrate inhibition was observed with D-glucose, 6-deoxy-D-glucose, or D-glucosamine as an acceptor, with D-glucose being most inhibiting. This inhibition was studied in detail and it was found that D-glucose competes with alpha-D-glucose-1-phosphate for its binding site. A model of competitive substrate inhibition was proposed, and the experimental data fit well to the theoretical values that were calculated in accordance with this model.     

Isomeric, anti-rhamnose antibodies having specificity for rhamnose-containing, streptococcal heteroglycans

L-Rhamnose (6-deoxy-L-mannose) is a constituent carbohydrate unit of microbial, immunogenic heteroglycans and lipopolysaccharides, and often functions as the immunodeterminant group of such immunogens. Two types of anti-rhamnose antibody have now been isolated by affinity chromatography of immune sera obtained from rabbits immunized with vaccines of Streptococcus mutans, strain KI-R, and Streptococcus pneumoniae, type 32. The antibodies of one type were directed at a glycan of L-rhamnose, D-glucose, and D-galactose in the cell wall of S. mutans, and those of the other type, against a capsular glycan of L-rhamnose and D-glucose from S. pneumoniae. The two types of anti-rhamnose antibody were immunologically distinct, and showed no reciprocal cross-reactivity. Additional properties of the two types of antibody were determined; thus, both types of antibody were of the IgG class of immunoglobulins, both possessed molecular weights of 1.45 X 10(5), and both consisted of multiple or isomeric forms.     

Neutral-sugar transport by rat liver lysosomes.

Transport of D-glucose was studied in Percoll-gradient-purified rat liver lysosomes. D-Glucose uptake had a Km of 22 mM and a t1/2 of approx. 30 s. D-Fucose, 2-deoxyglucose and methyl alpha-glucoside were the most effective competitors for uptake of D-glucose, although D-galactose, D-mannose, D-xylose and L-fucose also appeared to compete for uptake. L-Glucose was a poor competitor for uptake. No competition was observed with N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, D-glucuronic acid, N-acetylneuraminic acid, D-glucosamine or the amino acids L-glycine, L-lysine and L-proline. Uptake was unaffected by N-ethylmaleimide, dithiothreitol, KCl, NaCl, ATP/Mg or alteration of buffer pH. D-Glucose efflux from lysosomes was temperature-dependent, with a Q10 of 2.3, and was inhibited by cytochalasin B. Counter-transport could not be demonstrated. In contrast, L-fucose uptake had a Km of 65 mM and was largely unaffected by 5 M excess of neutral D-sugars. Both uptake and efflux of L-fucose were inhibited by cytochalasin B. It appears that lysosomes possess a facilitated transport system for D-glucose and perhaps other neutral D-sugars that is discrete from transport systems for acetylated and acidic sugars.     

Phage receptor material in Lactobacillus casei.

In Lactobacillus casei S-I, D-galactosamine and L-rhamnose comprised a phage receptor for phage J-I. A mixture of D-galactosamine and L-rhamnose effectively inactivated phage J-I, and a J-I-resistant mutant strain, L. casei S-I/J-I, lacked D-galactosamine in its surface component. The phage-inactivating effects of D-galactosamine and L-rhamnose were strongly dependent on the concentration of each substance and on temperature. It is suggested that the receptor for phage J-I involves both D-galactosamine in the cytoplasmic membrane and L-rhamnose in the wall of the host bacterium L. casei S-I, which lacts teichoic acid in its wall.     

三齿草藤(Vicia bungei Ohwi)凝集素糖组分的高效液相色谱分析

本文报道经亲和层析纯化的三齿草藤凝集素(VBL)的糖含量和糖组分的测定结果。经酚-硫酸法测得VBL的总糖含量为4.7％。应用高效液相色谱法对一系列已知标准单糖的定性定量分析条件进行了探索,选用乙腈-水-甲醇=60:30:5体系作流动相,YWG-NH_2作固定相,在高效液相色谱仪中测出VBL含有核糖和鼠李糖,二者摩尔数之比为9.4:1。     

Isolation and some properties of a lectin from the venom of the Vietnamese scorpion Buthus occitanus sp

A lectin was isolated from the venom of scorpion Buthus occitanus sp. by means of Sephadex G-50 gel filtration and CM-cellulose ion exchange chromatography. The homogeneous lectin preparation consisted of homodimeric molecules with a subunit Mr of 9.3 kDa. Glycine, alanine, and serine dominated in the lectin amino acid composition. The lectin was a glycoprotein containing 20% carbohydrates (predominantly mannose and glucose). Trypsin-treated murine erythrocytes agglutinated at the lectin concentration of 32 micrograms/ml. Hemagglutination was inhibited by carbohydrates (L-fucose > D-glucose > L-rhamnose > D-xylose). The lectin revealed no phospholipase or hyaluronidase, nor toxic activity.     

Identification of the lipopolysaccharide core region as the receptor site for a cytotoxin-converting phage, phi CTX, of Pseudomonas aeruginosa.

A temperate phage, phi CTX, is a cytotoxin-converting phage of Pseudomonas aeruginosa. In this study, we characterized the lipopolysaccharide (LPS) structures of phi CTX-resistant mutants derived from phi CTX-sensitive strains. phi CTX infectivity was neutralized by LPS preparations derived from sensitive strains but not by those from resistant strains. phi CTX-resistant mutants had lower-molecular-weight rough (R)-type LPS than the parental strains and lacked the reactivity of some anti-LPS core monoclonal antibodies. Some LPS core components were lacking or significantly decreased in the resistant mutants. These results suggested that a receptor site of the cytotoxin-converting phage phi CTX was the LPS core region and that especially L-rhamnose and D-glucose residues in the outer core were involved in phage binding. The host range of phi CTX was nearly O-serotype dependent, probably because of the diversity of the LPS core structure among P. aeruginosa strains. phi CTX bound to most strains of Homma serotypes A, G, and I but not to strains of serotypes B and E. Furthermore, we found that a genetic locus specifying phi CTX sensitivity (and consequently participating in the biosynthesis of part of the LPS core) existed in or near the locus participating in the determination of O-serotype specificity (somA), which has been mapped between leu-10 and eda-9001. phi CTX, as well as anti-LPS core monoclonal antibodies, will be a good tool for structural characterization of the P. aeruginosa LPS core region.     

Glucose and insulin co-regulate the glucose transport system in primary cultured adipocytes. A new mechanism of insulin resistance

We have previously shown in primary cultured rat adipocytes that insulin acts at receptor and multiple postreceptor sites to decrease insulin's subsequent ability to stimulate glucose transport. To examine whether D-glucose can regulate glucose transport activity and whether it has a role in insulin-induced insulin resistance, we cultured cells for 24 h in the absence and presence of various glucose and insulin concentrations. After washing cells and allowing the glucose transport system to deactivate, we measured basal and maximally insulin-stimulated 2-deoxyglucose uptake rates (37 degrees C) and cell surface insulin binding (16 degrees C). Alone, incubation with D-glucose had no effect on basal or maximal glucose transport activity, and incubation with insulin, in the absence of glucose, decreased maximal (but not basal) glucose transport rates only 18% at the highest preincubation concentration (50 ng/ml). However, in combination, D-glucose (1-20 mM) markedly enhanced the long-term ability of insulin (1-50 ng/ml) to decrease glucose transport rates in a dose-responsive manner. For example, at 50 ng/ml preincubation insulin concentration, the maximal glucose transport rate fell from 18 to 63%, and the basal uptake rate fell by 89%, as the preincubation D-glucose level was increased from 0 to 20 mM. Moreover, D-glucose more effectively promoted decreases in basal glucose uptake (Ki = 2.2 +/- 0.4 mM) compared with maximal transport rates (Ki = 4.1 +/- 0.4 mM) at all preincubation insulin concentrations (1-50 ng/ml). Similar results were obtained when initial rates of 3-O-methylglucose uptake were used to measure glucose transport. D-glucose, in contrast, did not influence insulin-induced receptor loss. In other studies, D-mannose and D-glucosamine could substitute for D-glucose to promote the insulin-induced changes in glucose transport, but other substrates such as L-glucose, L-arabinase, D-fructose, pyruvate, and maltose were without effect. Also, non-metabolized substrates which competitively inhibit D-glucose uptake (3-O-methylglucose, cytochalasin B) blocked the D-glucose plus insulin effect.(ABSTRACT TRUNCATED AT 400 WORDS)