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PubMed1982

The biosynthesis and linkage of teichuronic acid to peptidoglycan in Bacillus licheniformis.

Membrane and wall-membrane preparations of Bacillus licheniformis 94 will, if supplied with the appropriate precursors, synthesize teichuronic acid and link it to peptidoglycan although teichuronic acid is absent from walls of this organism. B. licheniformis 94 lacks phosphoglucomutase activity and therefore cannot synthesize the precursor UDPglucuronic acid. The initial reaction of teichuronic acid biosynthesis is catalysed by a translocase and results in the formation of polyprenyl-diphospho-N-acetylgalactosamine and the release of UMP. This reaction is not inhibited by tunicamycin. The disaccharide repeating unit of the polymer is then formed by the transfer of glucuronic acid from UDPglucuronic acid with the release of UDP. Polymerization of the repeating units occurs by incorporation of new units at the reducing terminus of the growing teichuronic acid chain and the release of polyprenyl diphosphate. The subsequent dephosphorylation of the lipid diphosphate for reuse in the biosynthesis cycle is inhibited by bacitracin. Linkage to peptidoglycan occurs by the formation of a phosphodiester bond between the reducing N-acetylgalactosamine terminus of the teichuronic acid chain and a 6-hydroxyl group of a muramic acid residue in the glycan of peptidoglycan. Wall-membrane preparations synthesizing teichuronic acid, poly(glycerol phosphate) teichoic acid and peptidoglycan link the teichuronic and teichoic acids to different glycan chains.

Anti-Bacterial Agents↗
PubMed1970

Derepression of beta-lactamase (penicillinase in Bacillus cereus by peptidoglycans.

In Bacillus cereus 569 a cellular inducer of beta-lactamase was isolated which has the same constituents and basic structure as the soluble peptidoglycan found in sporulation, extracts from spores, and germination extracts, and which was previously called "spore-peptide." The material has been extensively purified and characterized. Two acid-soluble, high-molecular-weight peptidoglycan fractions containing muramic acid, glucosamine, diaminopimelic acid, d-aspartate, and d- and l-alanine, -lysine, -glycine, and -glutamate, distinguishable on the basis of size and different amino acid to amino sugar ratios, have been found to be responsible for the observed induction. Both fractions are capable of inducing high levels of beta-lactamase in concentrations lower than those of benzyl penicillin required for optimal induction. Several experiments also suggest that it is the accumulation of such soluble peptidoglycan in penicillin-treated cells which leads to induction of beta-lactamase and not the penicillin itself. The "spore-peptide" inducer becomes available during sporulation, and endogenous derepression of beta-lactamase activity occurs simultaneously. Such derepression also occurs in a strain of B. cereus very sensitive to penicillin and in which both uninduced as well as "spore-peptide"-induced beta-lactamase is a small fraction of that produced by the typical penicillinase producer. These results suggest that beta-lactamase in B. cereus functions in cell wall metabolism during sporulation.

Bacillus cereus↗
PubMed1972

Isolation and partial chemical characterization of the spore appendages of Clostridium taeniosporum.

The spore appendages of Clostridium taeniosporum NI were removed from the spores by sonic treatment and were isolated by using discontinuous sucrose gradients. The amino acid composition of the appendages, which are elaborations of the spore coat, was similar to but not identical with the amino acid composition of the coats. Approximately 80% of the appendage dry weight was composed of 17 common amino acids, whereas 68% of the spore coat dry weight was amino acids. Mole ratios of the amino acids differed between the appendages and spore coats. The appendages contained neither diaminopimelic acid nor hydroxyproline. Glucosamine was an abundant constituent but muramic acid was absent. Approximately 10% of appendage dry weight consisted of three sugars, one of which was glucose. Phosphorus content was high and dipicolinic acid was absent. Appendage fine structure was not affected by common buffers, dilute acids and bases, hydrogen bond-breaking agents, certain proteolytic enzymes, or lysozyme.

Amino Acids↗
PubMed1977

The mode of hydrolysis of a glycan portion of Micrococcus lysodeikticus cell walls by endo-N-acetylglucosaminidase or endo-N-acetylmuramidase isolated from crude barley beta-amylase.

Micrococcus lysodeikticus cell walls were digested with a pI 6.8 endo-N-acetylglucosaminidase or a pI 9.5 endo-N-acetylmuramidase. The digests were further treated with a N-acetylmuramyl-L-alanine amidase of Flavobacterium L-11 enzyme to remove the peptide portion. The products were fractionated by gel filtration and ion-exchange chromatography, and the glycan portion of fractions were analyzed for their average amino sugar chain lengths. The following results were obtained. 1. The glycan portion of the main products in the pI 6.8 enzyme digest consisted of (-N-acetylmuramic acid-N-acetyl-glucosamine-)2-3. 2. The glycan moiety of the pI 9.5 enzyme digest was mainly composed of (-N-acetylglucosamine-N-acetylmuramic acid-)3-4. 3. The glycosidic linkages around the muramic acid 6-phosphate residues which linked to a special structure through a phosphodiester bond were rather refractory to the glycosidase action of both pI 6.8 and 9.5 enzymes.

Acetylglucosaminidase↗
PubMed1981

Stimulation of nonspecific resistance to infection induced by 6-O-acyl muramyl dipeptide analogs in mice.

The experimental system utilized in investigating the correlation between the chemical structures of muramyl peptides and their protective activities in the sepsis type of systemic infections caused by Escherichia coli was applied in evaluating the enhancement of resistance to infection induced by 32 synthetic glycopeptide analogs, including 6-O-acyl derivatives and 1-alpha-O-benzyl derivatives of muramyl dipeptide (N-acetyl muramyl-L-alanyl-D-isoglutamine). In assessing the 6-O-acyl derivatives of muramyl dipeptide, we found that the degree of protective activity was attributable to the kinds of fatty acids introduced. Acylation of the 6-hydroxy group on the muramic acid moiety in muramyl dipeptide with natural mycolic acid or a synthetic fatty acid possessing either an alpha-branched or an alpha-branched, beta-hydroxylated group resulted in a decrease in or a disappearance of the protective activity of muramyl dipeptide. Acylation with a normal fatty acid or an iso fatty acid resulted in a retention or enhancement of muramyl dipeptide activity. The activity of acylated derivatives containing linear fatty acids was stimulated by increasing the chain length up to 18 carbon atoms. The highest degree of protective activity occurred with the derivatives acylated with straight-chain fatty acids, particularly with the derivatives acylated with palmitic acid and arachidic acid. Benzylation of the 1-hydroxy group of muramyl dipeptide resulted in a decrease in or a loss of protective activity.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1990

[Chemical structure and immunobiological activities of peptidoglycan isolated from Capnocytophaga species].

The chemical structure and immunobiological activities of the cell wall peptidoglycan isolated from Capnocytophaga species was investigated. Peptidoglycan was isolated from Capnocytophaga species strain SE2-2 by boiling in 4% sodium dodecyl sulfate and by digestion with pronase, trypsin and alpha-amylase. Analysis of amino acids and amino sugars of the peptidoglycan revealed that glucosamine, muramic acid, D-glutamic acid, alanine, and diaminopimelic acid (A2pm) were the principal components. Serine and glycine were not found. Dinitrophenylation method revealed that about half of A2pm residue had a free amino group, and analysis by hydrazinolysis showed that a small part of alanine and A2pm located at the C-terminal. The above results indicate that one of the amino groups of A2pm residue at one strand of the stem peptide subunit cross-linked to the carboxyl group of alanine of the neighboring strand. It was thus revealed that the peptidoglycan of Capnocytophaga species belonged to the Al gamma type of the classification by Schleifer and Kandler. Peptidoglycan isolated from Capnocytophaga species strain SE2-2 was found to be definitely adjuvant-active in induction of delayed type hypersensitivity against ovalbumin when administered to guinea pigs as water-in-oil emulsion and in stimulation of increase serum antibody levels. Regarding mitogenicity on splenocytes of BALB/c and BALB/c nu/nu mice, peptidoglycan from Capnocytophaga species was markedly enhanced the uptake [3H] thymidine in dose of 10 micrograms/10(5) cells, however thymocytes were not reactive. Stimulation effects on peritoneal macrophages from a guinea pig to incorporation of 14C-glucosamin was exhibited by addition of 100 micrograms of this peptidoglycan. These findings indicate that peptidoglycan of Capnocytophaga species might eventually be responsible for destruction of periodontal tissue by host mediated activities.

Amino Acids↗
PubMed1989

[Chemical structure and immunomodulating activities of peptidoglycan from Actinobacillus actinomycetemcomitans].

The chemical structure and immunomodulating activities of the cell wall peptidoglycans isolated from Actinobacillus actinomycetemcomitans were investigated. Peptidoglycans were isolated from A. actinomycetemcomitans strains Y4 and ATCC 29522 by boiling in 4% sodium dodecyl sulfate and by digestion with pronase, trypsin and alpha-amylase. Analysis of amino acids and amino sugars of the peptidoglycans revealed that glucosamine, muramic acid, D-glutamic acid, D-alanine, and meso-2, 6-diaminopimelic acid (A2pm) were the principal components. Serine and glycine were not found. Dinitrophenylation method revealed that about half of A2pm residue had a free aminogroup, and analysis by hydrazinolysis showed that a small part of alanine and A2pm located at the C-terminal. The above results indicate that one of the amino groups of A2pm residue at one strand of the stem peptide subunit crosslinked to the carboxyl group of alanine of the neighboring strand. It was thus revealed that the peptidoglycans of A. actinomycetemcomitans belonged to the Al gamma type of the classification by Schleifer and Kandler. Peptidoglycans isolated from A. actinomycetemcmitans strain Y4 and ATCC 29522 were found to be definitely adjuvant-active in induction of delayed type hypersensitivity against ovalbumin when administered to guinea pigs as water-in oil emulsion and stimulation of increase serum antibody levels was found in both peptidoglycans. Regarding mitogenicity on splenocytes of BALB/c and BALB/c nu/nu mice, peptidoglycans from two strains of A. actinomycetemcomitans were markedly enhanced the uptake [3H] thymidine in dose of 10 micrograms/10(5) cells, however thymocytes were not reactive. Stimulation effects on peritoneal macrophages from a guinea pig to incorporation of 14C-glucosamin were not exhibited on addition of 100 micrograms of both peptidoglycans. These findings indicate that peptidoglycan of A. actinomycetemcomitans might eventually be responsible for destruction of periodontal tissue by host mediated activities.

Actinobacillus↗
PubMed1981

Structure of rigid-layer of Rhizobium cell wall. I. Purification on the peptidoglycan from the cellulose microfibrils.

The bag shaped peptidoglycan layer of Rhizobium cell wall was isolated from intact cells after treatment with sodium dodecylsulfate and trypsin, chymotrypsin or pepsin digestion. Results of chemical analysis of acid hydrolyzed peptidoglycan revealed beside two amino sugars: glucosamine and muramic acid, three major amino acids; alanine, glutamic acid and 2,6-diaminopimelic acid and also significant amount of glucose. Evidence were provided that the polyglucose found in peptidoglycan preparations of three strains of Rhizobium trifolii, one of Rhizobium leguminosarum and one of Rhizobium meliloti consist of cellulose microfibrils. The content of cellulose present in Rhizobium peptidoglycans ranged from 60 to 80%. Methods of peptidoglycan purification from the cellulose microfibrils are described.

Amino Acids↗
PubMed2002

Okibacterium fritillariae gen. nov., sp. nov., a novel genus of the family Microbacteriaceae.

Okibacterium fritillariae gen. nov., sp. nov. (type strain VKM Ac-2059T = IFO 16404T) is proposed for aerobic, oxidase- and catalase-positive, coryneform bacteria isolated from seeds of Fritillaria ruthenica Wikstr. and Clematis recta L. Strains of the new genus form a distinct branch within the phylogenetic cluster composed of members of the family Microbacteriaceae and are characterized by B-type peptidoglycan containing amino acids glycine, glutamate, homoserine, alanine and lysine, the glycolyl type of muramic acid, the major menaquinones MK-10 and MK-11, the principal phospholipids phosphatidylglycerol and diphosphatidylglycerol, and a DNA G+C content of approximately 67 mol %.

Actinomycetales↗
PubMed1984

The cell wall of the obligate intracellular bacterial parasite of small free-living amoebae. I. Morphology and chemical composition of the rigid layer and peptidoglycan.

The obligate intracellular bacterial parasite "OIBP" of small free-living amoebae, discovered by Drozański (1956) was propagated in axenic culture of Acanthamoeba castellanii. The peptidoglycan prepared by chemical extraction of intact cells of the bacterium was examined in a transmission electron microscope and analysed chemically. Electron micrographs of heavy metal shadowed preparations revealed a bag-shaped membraneous structure resembling that of the peptidoglycan sacculi of Escherichia coli and the other gram-negative bacteria so far studied. The peptidoglycan may be present in a lipoprotein-peptidoglycan complex, as proteolytic enzyme treatment resulted in changes of the ultrastructure and in chemical composition. Results of chemical analysis of acid hydrolysed peptidoglycan indicate the presence of two aminosugars; glucosamine and muramic acid and also significant amounts of glycine together with three major amino acids; alanine, glutamic acid and diaminopimelic acid. It was shown that the peptidoglycan was, however, resistant to the hydrolytic action of egg-white lysozyme and to the lysosomal endo N-acetylmuramidases of amoebael origin.

Amino Acids↗
PubMedDate not supplied

[Ratio of glycan to teichoic acid in Actinomyces thermovulgaris cell wall].

The molar ratio between glycan and teichoic acid was studied in the cell wall of Actinomyces thermovulgaris. A chain of teichoic acid consisting of 13 glycerophosphate units was found to correspond to 6--7 disaccharide units of glycan. The cell wall contains 31% of the glycan of the glycopeptide and 25% of teichoic acid. The content of glycan was calculated using the concentration of muramic acid in the wall. The cell wall was found to contain 1.02% of O-acetyl groups.

Actinomyces↗
PubMed2004

Rhodococcus gordoniae sp. nov., an actinomycete isolated from clinical material and phenol-contaminated soil.

The taxonomic relationships of two actinomycetes provisionally assigned to the genus Rhodococcus were determined using a polyphasic taxonomic approach. The generic assignment was confirmed by 16S rRNA gene similarity data, as the organisms, strains MTCC 1534 and W 4937(T), were shown to belong to the Rhodococcus rhodochrous subclade. These organisms had phenotypic properties typical of rhodococci; they were aerobic, Gram-positive, weakly acid-fast actinomycetes that showed an elementary branching-rod-coccus growth cycle and contained meso-diaminopimelic acid, arabinose and galactose in whole-organism hydrolysates, N-glycolated muramic acid residues, dehydrogenated menaquinones with eight isoprene units as the predominant isoprenologue and mycolic acids that co-migrated with those extracted from the type strain of R. rhodochrous. The strains had identical phenotypic profiles and belong to the same genomic species, albeit one distinguished from Rhodococcus pyridinivorans, with which they formed a distinct phyletic line. They were also distinguished from representatives of all of the species classified in the R. rhodochrous 16S rRNA gene tree using a set of phenotypic features. The genotypic and phenotypic data show that the strains merit recognition as a novel species of Rhodococcus. The name proposed is Rhodococcus gordoniae sp. nov., with the type strain W 4937(T) (=DSM 44689(T)=NCTC 13296(T)).

DNA, Bacterial↗
PubMedDate not supplied

Properties of microorganisms isolated from human leprosy lesions.

Diphtheroids, which in addition to Mycobacterium leprae are present in human leprosy lesions, were identified as true corynebacteria by DNA and cell wall analysis. Peptidoglycan (adjuvant) of these leprosy-derived corynebacteria (LDC) consists of N-acetylglycosaminyl-N-acetyl(glycolyl)-muramic acid and L-Ala-D-Glu(NH2)-(L)-meso-A2pm-(L)-D-Ala (A2pm = diaminopimelic acid). (The amino group of the tetrapeptide is attached to the carboxyl group of the muramate). Peripheral polysaccharide (antigen) is arabinogalactomannan with lateral chains of mannofuranose and arabinofuranose. To the latter are linked mycolic acids containing groups of isomers with 24-36 carbon atoms and containing between zero and four double bonds. DNAs of LDC isolates have a guanine + cytosine content of 56% and demonstrate a high degree of homology. LDC ribosomes cross-react with antisera against mycobacteria and with sera from patients with leprosy. Thermostable antigen M of LDC cross-reacts with the main antigens of tuberculin and lepromin. LDC thus represents a homogeneous and unique group of corynebacteria immunologically related to M. leprae. Leprosy might be the result of a pathogenic cooperation between both organisms, as suggested by the enhancement of M. leprae growth rate promoted in mice by living LDC.

Cell Wall↗
PubMed1989

Biological activities and chemical composition of purified tracheal cytotoxin of Bordetella pertussis.

Specific destruction of ciliated epithelial cells lining the large airways is the primary respiratory tract cytopathology associated with human Bordetella pertussis infections. We have purified a single low-molecular-weight glycopeptide, tracheal cytotoxin (TCT), that appears to cause this pathology. By using a combination of solid-phase extraction and reversed-phase high-pressure liquid chromatography, about 700 nmol of biologically active peptide can be isolated from 1 liter of B. pertussis culture supernatant (approximately 60% yield). TCT at concentrations of 1 microM destroyed the ciliated cell population when incubated with respiratory epithelium in vitro. This concentration of TCT is similar to the concentrations found in the culture supernatant of growing B. pertussis. Purified TCT also inhibited DNA synthesis of hamster trachea epithelial cells in a quantitative, dose-dependent fashion. Endotoxin was not detected in the purified material, and neither B. pertussis nor Escherichia coli endotoxin could duplicate the biological activities of TCT. Amino acid and amino sugar analyses of purified TCT revealed the presence of glucosamine, muramic acid, alanine, glutamic acid, and diaminopimelic acid in molar ratios of 1:1:2:1:1. This suggests that TCT, the released ciliostatic principle of B. pertussis, is a disaccharide tetrapeptide subunit of peptidoglycan.

Amino Acids↗
PubMed1980

Extent of peptide cross-linking in the peptidoglycan of Neisseria gonorrhoeae.

The extent of peptide cross-linking in peptidoglycan (PG) isolated from various strains of Neisseria gonorrhoeae was examined. Purified PG, specifically labeled in the peptide moiety with [(3)H]diaminopimelic acid (DAP) and labeled in the glycan with [(14)C]glucosamine and [(14)C]muramic acid, was digested completely with Chalaropsis B muramidase. Gel filtration of the digest on connected columns of Sephadex G-50 and G-25 revealed four well-defined peaks corresponding to soluble PG fragments and containing a constant ratio of (3)H to (14)C. On the basis of (i) K(D) values, (ii) amino acid composition, (iii) free amino group analysis of [(3)H]DAP residues, (iv) borohydride reduction, (v) the beta-elimination reaction, (vi) high-voltage electrophoresis, and (vii) paper chromatography in various solvents, the PG fragments were identified as un-cross-linked disaccharide peptide monomer, typical of chemotype I PG, and the corresponding peptide cross-linked dimers, trimers, and tetramers. The percent cross-linking of PG basically reflects the percentage of DAP residues that are involved in peptide cross-linking bonds. This value was estimated from the distribution of labeled fragments that resulted from the enzymatic digestion of PG and was confirmed by the analysis of free amino groups in [(3)H]DAP of intact PG. Although there were subtle, strain- and medium-dependent differences in percent cross-linking, these values varied only over a relatively narrow range (36 to 44%). The percent cross-linking of PG in the prototype strain, RD(5), grown in a standard gonococcal medium (LGCB(+)) was 41.0 +/- 2.0%. This is a relatively high degree of peptide cross-linking for a gram-negative bacterium. We also confirmed previous observations that the extent of PG cross-linking among isogenic gonococci was higher in strains, e.g., FA140 and FA136, carrying loci that govern increased resistance to multiple drugs.

Amino Acids↗
PubMed1984

N-acetylmannosaminyl(1----4)N-acetylglucosamine, a linkage unit between glycerol teichoic acid and peptidoglycan in cell walls of several Bacillus strains.

The structure of teichoic acid-glycopeptide complexes isolated from lysozyme digests of cell walls of Bacillus subtilis (four strains) and Bacillus licheniformis (one strain) was studied to obtain information on the structural relationship between glycerol teichoic acids and their linkage saccharides. Each preparation of the complexes contained equimolar amounts of muramic acid 6-phosphate and mannosamine in addition to glycopeptide components and glycerol teichoic acid components characteristic of the strain. Upon treatment with 47% hydrogen fluoride, these preparations gave, in common, a hexosamine-containing disaccharide, which was identified as N- acetylmannosaminyl (1----4) N-acetylglucosamine, along with large amounts of glycosylglycerols presumed to be the dephosphorylated repeating units of teichoic acid chains. The glycosylglycerol obtained from each bacterial strain was identified as follows: B. subtilis AHU 1392, glucosyl alpha (1----2)glycerol; B. subtilis AHU 1235, glucosyl beta(1----2) glycerol; B. subtilis AHU 1035 and AHU 1037, glucosyl alpha (1----6)galactosyl alpha (1----1 or 3)glycerol; B. licheniformis AHU 1371, galactosyl alpha (1----2)glycerol. By means of Smith degradation, the galactose residues in the teichoic acid-glycopeptide complexes from B. subtilis AHU 1035 and AHU 1037 and B. licheniformis AHU 1371 were shown to be involved in the backbone chains of the teichoic acid moieties. Thus, the glycerol teichoic acids in the cell walls of five bacterial strains seem to be joined to peptidoglycan through a common linkage disaccharide, N- acetylmannosaminyl (1----4)N-acetylglucosamine, irrespective of the structural diversity in the glycosidic branches and backbone chains.

Acetylglucosamine↗
PubMed1963

Mycobacterial cell walls. II. Chemical composition of the "basal layer".

Takeya, Kenji (Kyushu University, Fukuoka, Japan), Kazuhito Hisatsune, and Yasuko Inoue. Mycobacterial cell walls. II. Chemical composition of the "basal layer." J. Bacteriol. 85:24-30. 1963.-Chemical composition of the "basal layer" of the mycobacterial cell wall was determined. The layer contained 35% amino acids, 41.5% reducing sugars (mainly composed of arabinose and galactose), 13.8% amino sugars (glucosamine and muramic acid, 2:1), and 7.7% lipid. The main amino acids were alanine, glutamic acid, and diaminopimelic acid. Their molar ratio was approximately 2:2:1. The main difference in chemical composition between the cell wall and the basal layer was found in lipid content. According to the chemical composition, the basal layer resembles the walls of gram-positive bacteria, while the mycobacterial cell wall resembles the walls of gram-negative bacteria. The basal layer was thoroughly disintegrated by lysozyme digestion, and was considered to be an inner layer of the wall, conferring shape and rigidity on the mycobacterial cell wall.

Alanine↗
PubMed1970

Cell walls of pseudomonas species sensitive to ethylenediaminetetraacetic Acid.

Cell walls of 12 pseudomonads considered to be sensitive to ethylenediaminetetraacetic acid (EDTA) were prepared and analyzed. The wall of each species contained protein, peptidoglycan, loosely bound lipid, and lipopolysaccharide. The walls of Pseudomonas stutzeri and P. syncyanea were unusually susceptible to mechanical disintegration. The wall of P. syncyanea had an unusually high content of lipid and low contents of protein and peptidoglycan. Except for P. syncyanea, all the walls contained less phosphorus than the walls of the highly EDTA-sensitive P. aeruginosa and P. alcaligenes, but more than the walls of EDTA-resistant pseudomonads. The amino acid compositions of wall proteins were similar for all species. Amino sugars detected were glucosamine, galactosamine, muramic acid, and at least five unidentified components (possibly including fucosamine and quinovosamine). Glucose and rhamnose were the major neutral sugars in most walls. Galactose, mannose, fucose, and ribose were also detected, the last two each in a single species. Except for P. stutzeri and P. syncyanea, the walls had rather low contents of phospholipids (mainly cardiolipin, phosphatidylethanolamine, and phosphatidylglycerol in all species). An ornithine-containing nonphospholipid was present in all walls, and a hexuronosyldiglyceride was probably present in most walls. The fatty acid compositions of loosely bound lipids were qualitatively similar for all species: saturated C(16) and monoenoic C(16) and C(18) acids were the major components. Except for P. aureofaciens, the extraction of phosphorus on treatment of walls with EDTA at pH 9.2 was much less than for P. aeruginosa and P. alcaligenes.

Journal Article↗