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Glycerol teichoic acids were not detected immunochemically or chemically in phenol-water, hot saline (Rantz and Randall), or supernatant fluids of disrupted cells of Streptococcus mitis. Thus teichoic acids do not appear to be found in most Gram-positive bacteria, as has been suggested.
Cell walls of strains of Lactobacillus plantarum lacking the group D precipitinogen (a glucosylribitol teichoic acid) contain glucosylglycerol teichoic acid in which the glycosidic substituents are attached to the primary hydroxyl group of glycerol. Three distinct repeating units have been isolated from the teichoic acid preparation of strain C106, indicating either that the polymer is complex or that the wall contains a mixture of teichoic acids. Walls of streptobacteria differ from those of L. plantarum and contain neither teichoic acid nor diaminopimelic acid.
The occurrence of teichoic acids in cultures of Actinomadura genus was studied. All 30 strains examined in this survey contained alditol phosphate polymers. Most of the cultures had poly(glycerol phosphate) teichoic acids. Some of the poly(glycerol phosphate) chains bear madurose as a glycosyl substituent. In seven cultures glycerol teichoic acids with an unusual localization of the phosphodiester linkage were detected. Ribitol teichoic acids were found in six organisms.
Purified S. aureus ribitol teichoic acid was covalently bound to carboxylated latex particles. The immunological properties of the polysaccharide antigen were preserved. The reagent obtained was used for the quantification of anti-ribitol teichoic acid antibodies by means of a direct and rapid agglutination test carried out on a slide. There was good correlation between the preliminary results of this test and those obtained with counter-immunoelectrophoresis (CIE). The method is faster and more sensitive than CIE.
The release of lipoteichoic acid (LTA) and teichoic acid (TA) from a Streptococcus pneumoniae type 3 strain during exposure to ceftriaxone, meropenem, rifampin, rifabutin, quinupristin-dalfopristin, and trovafloxacin in tryptic soy broth was monitored by a newly developed enzyme-linked immunosorbent assay. At a concentration of 10 microg/ml, a rapid and intense release of LTA and TA occurred during exposure to ceftriaxone (3,248+/-1,688 ng/ml at 3 h and 3,827+/-2,133 ng/ml at 12 h) and meropenem (2,464+/-1,081 ng/ml at 3 h and 2,900+/-1,364 ng/ml at 12 h). Three hours after exposure to rifampin, rifabutin, quinupristin-dalfopristin, and trovafloxacin, mean LTA and TA concentrations of less than 460 ng/ml were observed (for each group, P < 0.01 versus the concentrations after exposure to ceftriaxone). After 12 h of treatment, the LTA and TA concentrations were 463+/-126 ng/ml after exposure to rifampin, 669+/-303 ng/ml after exposure to rifabutin, and 1,236+/-772 ng/ml after exposure to quinupristin-dalfopristin (for each group, P < 0.05 versus the concentrations after exposure to ceftriaxone) and 1,745+/-1,185 ng/ml after exposure to trovafloxacin (P = 0.12 versus the concentration after exposure to ceftriaxone). At 10 microg/ml, bactericidal antibacterial agents that do not primarily affect cell wall synthesis reduced the amount of LTA and TA released during their cidal action against S. pneumoniae in comparison with the amount released after exposure to beta-lactams. Larger quantities of LTA and TA were released after treatment with low concentrations (1x the MIC and 1x the minimum bactericidal concentration) than after no treatment for all antibacterial agents except the rifamycins. This does not support the concept of using a low first antibiotic dose to prevent the release of proinflammatory cell wall components.
Lipid analysis of several glycerol teichoic acid preparations strongly indicated that covalently bound lipid is not required for spontaneous adsorption of glycerol teichoic acid to erythrocyte membranes. Although fatty acids were detected in each of four batches, none were covalently bound. Chloroform-ether-extracted antigens retained potent erythrocyte membrane-binding activity as measured by passive hemagglutination, even though they were shown to contain less than one fatty acid residue per 4,869 teichoic acid chains. Mild ammonolysis abolished erythrocyte-sensitizing activity in passive hemagglutination, but further studies indicated the loss of activity was due to partial destruction of the polyglycerophosphate backbone and not to the removal of esterified lipid. The amount of hydrolyzed antigen required to produce 100% passive hemagglutination inhibition was between 170 and 330 times the amount required to produce the same result using unhydrolyzed glycerol teichoic acid. The average chain length was reduced from 19.1 to 9.7, 7.4, and 5.1 glycerophosphate residues for antigen samples hydrolyzed for 1, 5, and 16 h, respectively.
BACKGROUND: Staphylococcus aureus or MRSA (Methicillin Resistant S. aureus), is an acquired pathogen and the primary cause of nosocomial infections worldwide. In S. aureus, teichoic acid is an essential component of the cell wall, and its biosynthesis is not yet well characterized. Studies in Bacillus subtilis have discovered two different pathways of teichoic acid biosynthesis, in two strains W23 and 168 respectively, namely teichoic acid ribitol (tar) and teichoic acid glycerol (tag). The genes involved in these two pathways are also characterized, tarA, tarB, tarD, tarI, tarJ, tarK, tarL for the tar pathway, and tagA, tagB, tagD, tagE, tagF for the tag pathway. With the genome sequences of several MRSA strains: Mu50, MW2, N315, MRSA252, COL as well as methicillin susceptible strain MSSA476 available, a comparative genomic analysis was performed to characterize teichoic acid biosynthesis in these S. aureus strains. RESULTS: We identified all S. aureus tar and tag gene orthologs in the selected S. aureus strains which would contribute to teichoic acids sythesis. Based on our identification of genes orthologous to tarI, tarJ, tarL, which are specific to tar pathway in B. subtilis W23, we also concluded that tar is the major teichoic acid biogenesis pathway in S. aureus. Further analyses indicated that the S. aureus tar genes, different from the divergon organization in B. subtilis, are organized into several clusters in cis. Most interesting, compared with genes in B. subtilis tar pathway, the S. aureus tar specific genes (tarI,J,L) are duplicated in all six S. aureus genomes. CONCLUSION: In the S. aureus strains we analyzed, tar (teichoic acid ribitol) is the main teichoic acid biogenesis pathway. The tar genes are organized into several genomic groups in cis and the genes specific to tar (relative to tag): tarI, tarJ, tarL are duplicated. The genomic organization of the S. aureus tar pathway suggests their regulations are different when compared to B. subtilis tar or tag pathway, which are grouped in two operons in a divergon structure.
A teichoic acid of Nocardioides albus VKM Ac-805T cell walls, a typical species of the genus Nocardioides, contains a poly(glycosylglycerol phosphate). The repeating unit of the polymer has the structure: [figure]. These units are in phosphodiester linkage at C-3 of glycerol and C-3 of beta-D-galactopyranose. beta-D-Galactopyranosyl residues are substituted at C-4 by beta-D-glucopyranose carrying a 4,6-pyruvate ketal group in S-configuration. The presence of pyruvic acid in the majority of repeating units increases the anionic properties of the polymer in comparison with most other common teichoic acids. This is the first report of the occurrence of a beta-D-galactofuranosyl residue in teichoic acids; it probably acts as a terminator of an extending chain of the polymer. The ratio of beta-D-galactopyranosyl to beta-D-galactofuranosyl units is 7:1. The polymer structure was determined by NMR spectroscopy. This type of teichoic acid structure has not been reported previously.
Teichoic acids from the cell walls of marine bacilli Bacillus subtilis CMM (Collection of Marine Microorganisms) 234 (R-1) and B. licheniformis CMM 454 (1-1G-2) were isolated and characterized. These teichoic acids were found to have identical structures and are composed of the glucose, ribitol, and phosphoric acid residues. On the basis of 13C NMR and 31P NMR spectra of the teichoic acids and the products of their dephosphorylation, we established the following structure for the biopolymer: poly[-->5)-4-O-beta-D-glucopyranosylribitol-(1-phospho].
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An extensive study of teichoic acid biosynthesis in the model organism Bacillus subtilis has established teichoic acid polymers as essential components of the gram-positive cell wall. However, similar studies pertaining to therapeutically relevant organisms, such as Staphylococcus aureus, are scarce. In this study we have carried out a meticulous examination of the dispensability of teichoic acid biosynthetic enzymes in S. aureus. By use of an allelic replacement methodology, we examined all facets of teichoic acid assembly, including intracellular polymer production and export. Using this approach we confirmed that the first-acting enzyme (TarO) was dispensable for growth, in contrast to dispensability studies in B. subtilis. Upon further characterization, we demonstrated that later-acting gene products (TarB, TarD, TarF, TarIJ, and TarH) responsible for polymer formation and export were essential for viability. We resolved this paradox by demonstrating that all of the apparently indispensable genes became dispensable in a tarO null genetic background. This work suggests a lethal gain-of-function mechanism where lesions beyond the initial step in wall teichoic acid biosynthesis render S. aureus nonviable. This discovery poses questions regarding the conventional understanding of essential gene sets, garnered through single-gene knockout experiments in bacteria and higher organisms, and points to a novel drug development strategy targeting late steps in teichoic acid synthesis for the infectious pathogen S. aureus.
Enzymes involved in the synthesis of teichoic acid and its linkage to the wall in Bacillus subtilis W23 were measured in chemostat cultures growing at equilibrium at a dilution rate of 0.2 h-1 in different concentrations of inorganic phosphate. All the enzymes, except teichoic acid glucosyl transferase, which was insensitive to changes in phosphate concentration, were almost undetectable at 0.5 mM-phosphate. At higher phosphate concentrations the changes in activity of the enzymes of linkage unit synthesis were sufficient to account for the changes in the rate of incorporation of teichoic acid into the wall in vivo. Between 3.5 and 4.5 mM-phosphate the amount of teichoic acid synthesized in vivo increased, but no increase in the ability of toluenized bacteria to synthesize teichoic acid could be detected. Allosteric regulation might therefore be important at high phosphate concentrations. Bacteria maintained a constant ATP content and a constant adenylate energy charge during chemostat growth at all phosphate concentrations.
The structure of teichoic acids was studied in the cell walls of Streptomyces roseoflavus var. roseofungini 1128 and its Nocardia-like variant 1-68 differing from the parent strain in the absence of a spore-forming aerial mycelium as well as by the fragmentation of hyphae in the substrate mycelium. The teichoic acids of the both cultures consist of a 1,3-poly(glycerophosphate) chain containing 11-13 glycerolphosphate residues which have glucosamynl units and lysine groups bound through an ester bond. These teichoic acids contain no O-acetyl groups, in contrast to the glyceroteichoic acids of actinomycetes studied earlier. The teichoic acid from the cell wall of the variant has less lysine and glucosamine then the parent strain. The content of teichoic acid in the cell wall of the parent culture is 4.5 times greater than in the wall of the variant.
A teichoic acid from the cell walls of Nocardioides luteus VKM Ac-1246T, a validly described species of the Nocardioides genus, is a 1,5-poly(ribitol phosphate) completely substituted at C-4 by alpha-D-galactopyranosyl residues carrying a 4,6-pyruvate ketal group in R-configuration. The structure of the repeating unit of the polymer is as follows: [figure]. The chain consists of approximately 18 repeating units and six beta-D-galactofuranosyl residues linked in the oligomer by 1,6-glycosidic bonds. The oligomer probably terminates the growing end of the teichoic acid. The structure of the polymer was determined by chemical methods and NMR spectroscopy. This teichoic acid has not been described so far.
The structures of teichoic acids of three Nocardiopsis species were established. The cell wall of Nocardiopsis listeri VKM Ac-1881T contains two teichoic acids (TA). TA1 is 1,3-poly(glycerol phosphate) with 50% glycerol phosphate residues substituted by alpha-N-acetylglucosamine in the C-2 position. TA2 is 1, 5-poly(ribitol phosphate) with each ribitol phosphate unit carrying pyruvate acetal groups in the 2 and 4 positions. The cell wall of Nocardiopsis lucentensis VKM Ac-1963T contains only one teichoic acid of the same structure as TA1 of N. listeri. The teichoic acid of the Nocardiopsis tregalosei VKM Ac-942 is a 1,3-poly(glycerol phosphate) substituted (60%) by beta-glucopyranosyl residues. Structures of polymers were studied by chemical and NMR spectroscopy methods. The presented results confirm the species-specificity of teichoic acids from Nocardiopsis genus.
Autolysin-defective pneumococci continue to synthesize both peptidoglycan and teichoic acid polymers (Fischer and Tomasz, J. Bacteriol. 157:507-513, 1984). Most of these peptidoglycan polymers are released into the surrounding medium, and a smaller portion becomes attached to the preexisting cell wall. We report here studies on the degree of cross-linking, teichoic acid substitution, and chemical composition of these peptidoglycan polymers and compare them with normal cell walls. peptidoglycan chains released from the penicillin-treated pneumococci contained no attached teichoic acids. The released peptidoglycan was hydrolyzed by M1 muramidase; over 90% of this material adsorbed to vancomycin-Sepharose and behaved like disaccharide-peptide monomers during chromatography, indicating that the released peptidoglycan contained un-cross-linked stem peptides, most of which carried the carboxy-terminal D-alanyl-D-alanine. The N-terminal residue of the released peptidoglycan was alanine, with only a minor contribution from lysine. In addition to the usual stem peptide components of pneumococcal cell walls (alanine, lysine, and glutamic acid), chemical analysis revealed the presence of significant amounts of serine, aspartate, and glycine and a high amount of alanine and glutamate as well. We suggest that these latter amino acids and the excess alanine and glutamate are present as interpeptide bridges. Heterogeneity of these was suggested by the observation that digestion of the released peptidoglycan with the pneumococcal murein hydrolase (amidase) produced peptides that were resolved by ion-exchange chromatography into two distinct peaks; the more highly mobile of these was enriched with glycine and aspartate. The peptidoglycan chains that became attached to the preexisting cell wall in the presence of penicillin contained fewer peptide cross-links and proportionally fewer attached teichoic acids than did their normal counterparts. The normal cell wall was heavily cross-linked, and the cross-linked peptides were distributed equally between the teichoic acid-linked and teichoic acid-free fragments.