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P Messner

Publications and source records attributed to P Messner.

At least 55 records · Page 3Linked to original sources
PubMed1996

Are S-layer glycoproteins and lipopolysaccharides related?

Several glycan structures of S-layer glycoproteins of gram-positive eubacteria were compared with the principal structural organization of O-antigens of lipopolysaccharides of gram-negative eubacteria. Further, activated intermediates of the biosynthetic pathway of S-layer glycans were compared with activated intermediates of the route of assembly of lipopolysaccharide O-antigens. As a result, at least structural similarities between both types of molecules have been clearly observed. More detailed studies of the assembly of S-layer glycans are required to unambiguously demonstrate the extent to which the biosynthetic pathways of both molecules are related.

Bacillus↗
PubMed1996

Thermobrachium celere gen. nov., sp. nov., a rapidly growing thermophilic, alkalitolerant, and proteolytic obligate anaerobe.

More than 40 isolates of a novel, ubiquitous, proteolytic, moderately alkaliphilic, thermophilic obligate anaerobe were obtained from geothermally and anthropogenically heated environments and mesobiotic environments located on three continents. Whole-cell protein sodium dodecyl sulfate gel electrophoresis revealed that most of these organisms are very similar. Eight of the isolates were characterized in detail; this analysis included 16S ribosomal DNA sequence analysis. The cells of those organisms are (depending on the isolate) 0.5 to 0.8 micron in diameter and 1.5 to 13 microns long, exhibit tumbling motility, and have a positive Gram stain reaction. The temperature range for growth is 43 degrees to 75 degrees C (optimum temperature, 66 degrees C), and the pH range for growth is 5.4 to 9.5 (optimum pH, 8.2); the shortest doubling time is around 10 min. Yeast extract is required for growth, and (depending on the strain) glucose, sucrose, fructose, galactose, and ribose are utilized. The fermentation products from glucose in the presence of yeast extract are CO2, H2, acetate, formate, and ethanol. The G + C content is 30 to 31 mol%. On the basis of these properties, which differentiate these strains from all alkalitolerant thermophiles described previously, and the results of a comparison of the 16S ribosomal DNA sequences of these organisms with previously described sequences, we propose that our isolates be placed in a single species of the new genus Thermobrachium; strain JW/YL-NZ35 is the type strain of the the type species, Thermobrachium celere.

Bacteria, Anaerobic↗
PubMed1996

Anaerofilum pentosovorans gen. nov., sp. nov., and Anaerofilum agile sp. nov., two new, strictly anaerobic, mesophilic, acidogenic bacteria from anaerobic bioreactors.

Strictly anaerobic, gram-positive, nonsporing, thin rod-shaped organisms whose cells were 0.2 to 0.6 by 3 to 6 microns were isolated from a Hoechst Biohochreaktor (strain FaeT [T = type strain]) and from the biofilm population of a fixed-film reactor treating sour whey (strain FT). Strain FT was vigorously motile during early logarithmic growth by means of peritrichously inserted flagella, while strain FaeT was seldom motile and usually possessed no flagella. During the stationary growth phase both strains formed spheroplasts. The temperature optimum was close to 37 degrees C (temperature range for growth, > or = 17 to < 45 degrees C) and the pH optimum was 7.0 to 7.4 (pH range, 6.5 to 8.0) for both strains. The two organisms grew chemoorganotrophically on a number of mono- and disaccharides, including glucose and xylose; yeast extract was required for growth. The principal fermentation products from glucose included lactate, acetate, ethanol, formate, and CO2. Hydrogen was not generated. The G + C contents of the DNAs of strains FaeT and FT were 55 and 54.5 mol%, respectively. The cell wall architecture was typical of gram-positive bacteria; the cells had an extraordinarily thin type A3 alpha' peptidoglycan layer containing muramic acid. Analysis of 16S ribosomal DNA sequences of the two new isolates demonstrated that they represent members of a new genus of bacteria in Clostridium cluster IV of the domain Bacteria and that the misclassified organism Fusobacterium prausnitzii and Clostridium leptum are among their closest relatives. The names Anaerofilum pentosovorans gen. nov., sp. nov. (type strain, strain Fae [= DSM 7168]) and Anaerofilum agile sp. nov. (type strain, strain F [= DSM 4272]) are proposed.

Anaerobiosis↗
PubMed1995

Characterization of the glycan structure of a major glycopeptide from the surface layer glycoprotein of Clostridium thermosaccharolyticum E207-71.

The squarely arranged surface layer (S-layer) glycoprotein of Clostridium thermosaccharolyticum E207-71 was isolated from bacterial cells which were grown under defined culture conditions. By sodium dodecyl sulfate polyacrylamide gel electrophoresis, the S-layer showed a series of distinct bands with apparent molecular masses in the range 83-210 kDa. Upon deglycosylation by trifluoromethanesulfonic acid, only the single band at 83 kDa remained unchanged. After pronase digestion of the intact S-layer glycoprotein, the degradation products were isolated by gel-permeation chromatography, cation-exchange chromatography and isoelectric focusing. Three main fractions and an amino sugar containing minor fraction were obtained. The main fractions, which showed identical carbohydrate compositions, were further purified by reverse-phase chromatography and characterized by monosaccharide analysis, Smith degradation, methylation analysis, and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy. The combined chemical and spectroscopical evidence suggest the following glycan structure for the main fractions: [Sequence: See text]

Amino Acid Sequence↗
PubMed1995

Glycan structure of the S-layer glycoprotein of Bacillus sp. L420-91.

Preliminary taxonomic characterization of isolate L420-91 has revealed that this organism is closely related to the species Bacillus aneurinolyticus. The bacterium is covered by a squarely arranged crystalline surface layer composed of identical glycoprotein subunits with an apparent molecular mass in the range of 109 kDa. A total carbohydrate content of approximately 3.5% (wt/wt) was determined in the purified surface layer glycoprotein. Glycopeptides were obtained after exhaustive Pronase digestion and purification including gel filtration, ion exchange chromatography and HPLC. From the combined evidence of composition analysis. Smith degradation and nuclear magnetic resonance spectroscopy experiments we propose the following structure for the glycan chain of the surface layer glycoprotein: [formula: see text]

Acetamides↗
PubMed1995

Glycan structure of a heptose-containing S-layer glycoprotein of Bacillus thermoaerophilus.

The characterization of the S-layer glycoprotein of Bacillus thermoaerophilus revealed unexpected novelties. The isolation and purification procedure had to be changed due to complete solubility in aqueous buffers of the constituting S-layer protomers. Upon degradation of the S-layer glycoprotein by pronase and purification of the products by gel filtration, ion-exchange chromatography, chromatofocusing and HPLC, one representative glycopeptide fraction was selected for further characterization. From the combined evidence of composition analysis, chemical degradation, NMR spectroscopy experiments and comparison with synthesized model substance, we propose the following repeating unit structure of the glycan chain: -->4)-alpha-L-Rhap-(1-->3)-beta-D-glycero-D-manno-Hepp-(1--> This is the first description of heptose residues occurring as a constituent of S-layer glycoproteins of gram-positive eubacteria.

Bacillus↗
PubMed1995

Accurate determination of the molecular weight of the major surface layer protein isolated from Clostridium thermosaccharolyticum by time-of-flight mass spectrometry.

Matrix-assisted laser desorption with concomitant ionization, in combination with a linear time-of-flight mass spectrometer, was used to analyze underivatized and hard-to-solubilize surface layer proteins and glycoproteins by depositing them on top of a microcrystalline layer of the matrix alpha-cyano-4-hydroxycinnamic acid. Use of this special sample preparation technique allowed the first successful desorption-ionization of intact surface layer proteins and accurate determination of their molecular weights by mass spectrometry. The molecular mass of the monomeric subunit of the major surface layer protein isolated from Clostridium thermosaccharolyticum E207-71 was determined to be 75,621 +/- 81 Da. The obtainable mass accuracy of the technique is conservatively considered to be within +/- 0.2%. This result deviates from that given by sodium dodecyl sulfate-polyacrylamide gel electrophoresis by approximately 7.4 kDa because this method is strongly affected and biased by the three-dimensional structure of this type of surface protein. With the apparent advantages of unsurpassed mass accuracy, low dependence on the physicochemical properties of the surface layer proteins, and high sensitivity, it can be concluded that a linear time-of-flight instrument combined with UV matrix-assisted laser desorption with concomitant ionization is better suited for molecular weight determination than is gel electrophoresis.

Bacterial Outer Membrane Proteins↗
PubMed1995

Similarity of "core" structures in two different glycans of tyrosine-linked eubacterial S-layer glycoproteins.

Previously, the repeating-unit structure of the S-layer glycoprotein from the eubacterium Bacillus alvei CCM 2051 has been determined to be [-->3)-beta-D-Galp-(1-->4)-[alpha-D-Glcp-(1-->6)-]-beta-D-ManpNAc- (1-->]n (E. Altman, J.-R. Brisson, P. Messner, and U. B. Sleytr, Biochem. Cell Biol. 69:72-78, 1991). Nuclear magnetic resonance spectroscopic reexamination of this glycan reveals that the O-antigen-like domain of the polysaccharide is [see text] connected with the S-layer polypeptide through the "core" structure -->3)-alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->3)-alpha-L-R hap-(1-->3)-beta-D-Galp-(1-->O)-Tyr. Except for the substitution in position 4 of the nonreducing rhamnose with the modified glyceric acid phosphate residue GroA-2-->OPO2-->4-beta-D-ManpNAc-(1-->, this core is identical to the core of the tyrosine-linked glycan from the S-layer glycoprotein of Thermoanaerobacter thermohydrosulfuricus L111-69 (K. Bock, J. Schuster-Kolbe, E. Altman, G. Allmaier, B. Stahl, R. Christian, U. B. Sleytr, and P. Messner, J. Biol. Chem. 269:7137-7144, 1994).

Bacillus↗
PubMed1994

Primary structure of the O-glycosidically linked glycan chain of the crystalline surface layer glycoprotein of Thermoanaerobacter thermohydrosulfuricus L111-69. Galactosyl tyrosine as a novel linkage unit.

The products of Pronase digestion of the crystalline surface layer (S-layer) glycoproteins of Thermoanaerobacter thermohydrosulfuricus strains L111-69 and L110-69 were isolated by gel permeation chromatography, cation exchange chromatography, chromatofocusing, and reversed phase high performance liquid chromatography. Four compounds were obtained which were analyzed by monosaccharide analysis, one- and two-dimensional 500 and 600 MHz 1H and 13C NMR spectroscopy, methylation analysis, gas-liquid chromatography/mass spectrometry, and matrix-assisted laser desorption ionization mass spectrometry. For all glycopeptides we propose the following glycan structure with galactose as the linkage sugar. [formula: see text] The isolated glycopeptides resulted from Pronase cleavage at the glycosylated tyrosine residues. Tyrosine was found as the linkage amino acid in all fractions but the remaining amino acid sequences varied, indicating the presence of different glycosylation sites in the intact S-layer glycoprotein.

Bacterial Proteins↗
PubMed1994

Two-dimensional protein crystals (S-layers): fundamentals and applications.

Two-dimensional crystalline surface layers (S-layers) composed of protein or glycoprotein subunits are one of the most commonly observed prokaryotic cell envelope structures. Isolated S-layer subunits are endowed with the ability to assemble into monomolecular arrays in suspension, on surfaces or interfaces by an entropy-driven process. S-layer lattices are isoporous structures with functional groups located on the surface in an identical position and orientation. These characteristic features have already led to applications of S-layers as (1) ultrafiltration membranes with well-defined molecular weight cut-offs and excellent antifouling characteristics, (2) immobilization matrices for functional molecules as required for affinity and enzyme membranes, affinity microcarriers and biosensors, (3) conjugate vaccines, (4) carriers for Langmuir-Blodgett films and reconstituted biological membranes, and (5) patterning elements in molecular nanotechnology.

Animals↗
PubMed1994

Isolation of two physiologically induced variant strains of Bacillus stearothermophilus NRS 2004/3a and characterization of their S-layer lattices.

During growth of Bacillus stearothermophilus NRS 2004/3a in continuous culture on complex medium, the chemical properties of the S-layer glycoprotein and the characteristic oblique lattice were maintained only if glucose was used as the sole carbon source. With increased aeration, amino acids were also metabolized, accompanied by liberation of ammonium and by changes in the S-layer protein. Depending on the stage of fermentation at which oxygen limitation was relieved, two different variants, one with a more delicate oblique S-layer lattice (variant 3a/V1) and one with a square S-layer lattice (variant 3a/V2), were isolated. During the switch from the wild-type strain to a variant or from variant 3a/V2 to variant 3a/V1, monolayers of two types of S-layer lattices could be demonstrated on the surfaces of single cells. S-layer proteins from variants had different molecular sizes and a significantly lower carbohydrate content than S-layer proteins from the wild-type strain did. Although the S-layer lattices from the wild-type and variant strains showed quite different protein mass distributions in two- and three-dimensional reconstructions, neither the amino acid composition nor the pore size, as determined by permeability studies, was significantly changed. Peptide mapping and N-terminal sequencing results strongly indicated that the three S-layer proteins are encoded by different genes and are not derived from a universal precursor form.

Amino Acids↗
PubMed1994

[Arrhythmia due to mitral valve prolapse].

Mitral valve prolapse (MVP) a common condition easily recognised by echocardiography with, however, strict criteria to avoid diagnosis by excess, may be complicated by arrhythmias. Two very different situations oppose severe decompensated mitral regurgitation due to myxoid dystrophy and quasi-asymptomatic MVP with a good prognosis and a low risk of complications. The important question is therefore to detect risk criteria of sudden death in patients with few symptoms. Unfortunately, no isolated factor or association of factors resolves this problem in a given patient. However, it is usually young women without severe mitral regurgitation but with thickened valves and, sometimes, a long QT interval, who are involved. Programmed ventricular stimulation and the detection of later ventricular potentials do not seem to be useful in the present state of our knowledge.

Adult↗
PubMed1993

Induction of T-cell immunity to oligosaccharide antigens immobilized on crystalline bacterial surface layers (S-layers).

Immunization of Balb/c mice with conjugates of oligosaccharide haptens and crystalline bacterial surface-layer proteins (S-layers) primed the mice for a strong, hapten-specific, delayed-type hypersensitivity (DTH) response. Conjugates of haptens with bovine serum albumin produced only weak DTH responses but, when mixed with aluminium hydroxide, elicited DTH responses comparable to those against S-layer conjugates. Surface-layer conjugates also elicited strong anti-hapten DTH responses when administered by an oral/nasal route. Apparently, the natural assembly of S-layer proteins into large, two-dimensional arrays endows them with intrinsic adjuvant properties.

Adjuvants, Immunologic↗
PubMed1993

Crystalline bacterial cell surface layers.

Crystalline arrays of proteinaceous subunits forming surface layers (S-layers) are one of the most commonly observed prokaryotic cell envelope structures. They are ubiquitous amongst Gram-positive and Gram-negative archeaobacteria and eubacteria and, if present, account for the major protein species produced by the cells. S-layers can provide organisms with a selection advantage by providing various functions including protective coats, molecular sieves, ion traps and structures involved in cell surface interactions. S-layers were identified as contributing to virulence when present as a structural component of pathogens. In Gram-negative archaeobacteria they are involved in determining cell shape and cell division. The crystalline arrays reveal a broad-application potential in biotechnology, vaccine development and molecular nanotechnology.

Bacteria↗
PubMed1993

Proposed pathway for biosynthesis of the S-layer glycoprotein of Bacillus alvei.

The outer surface of the murein sacculus of the eubacterium Bacillus alvei is covered by a surface layer (S-layer) glycoprotein. The glycan chain of this S-layer glycoprotein consists of trisaccharide repeating units with ManNAc, Gal, and Glc as constituents. From cell extracts of B. alvei, nucleotide-activated derivatives of ManNAc, Gal, Glc, and GlcNAc were isolated. Furthermore, GDP- and dolichyl-activated oligosaccharides were obtained. On the basis of the isolated putative glycoprotein precursors, a pathway for the biosynthesis of the oligosaccharide chain is proposed.

Bacillus↗
PubMed1993

Complete structure of the tyrosine-linked saccharide moiety from the surface layer glycoprotein of Clostridium thermohydrosulfuricum S102-70.

In this study, we have extended and completed a previous investigation (P. Messner, R. Christian, J. Kolbe, G. Schulz, and U. B. Sleytr, J. Bacteriol. 174:2236-2240, 1992) in which we demonstrated for the first time in prokaryotic organisms the presence of a novel O-glycosidic linkage via tyrosine. The surface layer glycoprotein of the eubacterium Clostridium thermohydrosulfuricum S102-70 is arranged in a hexagonal lattice, with center-to-center spacings of approximately 16.3 nm. Molecular weight determination by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of both glycosylated and chemically deglycosylated surface layer glycoprotein showed values for the monomeric subunits of 94,000 and 87,500, respectively. Glycopeptide fractions obtained after exhaustive pronase digestion of purified, intact glycoprotein were isolated by reversed-phase liquid chromatography. One- and two-dimensional nuclear magnetic resonance studies, together with chemical analyses and plasma desorption time-of-flight mass spectrometry, were used to elucidate the structure of the hexasaccharide moiety linked by the novel O-glycosidic linkage to tyrosine. The combined evidence suggests the following structure: beta-D-Galf-(1-->3)-alpha-D-Galp- (1-->2)-alpha-L-Rhap-(1-->3)-alpha-D-Manp-(1--3)-alpha-L- Rhap-(1-->3)-beta- D-Glcp-(1-->4)-L-Tyr.

Bacterial Proteins↗
PubMed1993

[Ventricular tachycardia in children].

Ventricular tachycardia (VT) in children is different to that observed in the adult because ischemic heart disease is exceptionally rare in this age group. The arrhythmia sometimes presents with cardiac failure or loss of consciousness. VT complicates the outcome of operated Tetralogy of Fallot, arrhythmogenic right ventricular dysplasia and some cardiac tumours. Cardiomyopathies are also a cause of VT but it must be noted that ventricular dysfunction may be the result of a prolonged arrhythmia and will disappear after return to sinus rhythm. Many cases of childhood VT occur without any patent cardiac disease even after extensive investigations. Some are benign with a good prognosis, such as salvoes of VT or sustained attacks of so-called ventricular Bouveret. Others carry a more reserved prognosis and require active treatment. Incessant tachycardia of the newborn is difficult to stop may be cured without sequellae. Torsades de pointes is sometimes iatrogenic complicating congenitally long QT syndromes with or without deafness or familial nature, and which may be likened to adrenergic VT. Amiodarone and betablockers are the best antiarrhythmic agents. Investigations with a diagnostic or therapeutic objective are easier in older children but these techniques, whilst not being systematic, do not exclude the very young children. Ablation techniques progress and the limited indications of surgery and implantable defibrillators have to be considered case by case.

Adolescent↗