On the basic structure of poly (glycerophosphate) lipoteichoic acids

1990 ◽  
Vol 68 (1) ◽  
pp. 33-43 ◽  
Author(s):  
Werner Fischer ◽  
Tibor Mannsfeld ◽  
Gerhard Hagen
Keyword(s):  
Acetic Acid ◽  
Periodate Oxidation ◽  
Hydrophobic Interaction Chromatography ◽  
Basic Structure ◽  
Bacterial Membrane ◽  
Gram Positive ◽  
Molar Ratios ◽  
Gram Positive Bacteria ◽  
Oral Group ◽  
Lipoteichoic Acids

Poly(glycerophosphate) lipoteichoic acids from 24 Gram-positive bacteria of the genera Bacillus, Enterococcus, Lactobacillus, Lactococcus, Listeria, Staphylococcus, and the streptococcal pyogenic and oral group were analyzed. The 1,3-linked poly(glycerophosphate) structure was proved by analysis of glycerol and glycerophosphates after acid and alkaline hydrolysis. Using the molar ratios of glycolipid to phosphorus (A) and phosphomonoester to phosphorus after periodate oxidation followed by hydrazinolysis (B) or β-elimination (C), we show that all lipoteichoic acids contain a single unbranched poly(glycerophosphate) chain and that the chain is uniformly phosphodiester-linked to C-6 of the nonreducing hexopyranosyl residue of the glycolipid moiety. On some chains minor phosphate-containing substituents were detected whose structure remains to be clarified. The lipoteichoic acids of enterococci and listeria strains were separated by hydrophobic interaction chromatography into glycolipid- and phosphatidylglycolipid-containing molecular species. The phosphatidylglycolipid moieties were structurally characterized after liberation from lipoteichoic acids with moist acetic acid. After periodate oxidation of lipoteichoic acids β-elimination released both phosphatidic acid and the poly(glycerophosphate) chain. This indicates together with the sequence analysis of the released phosphatidylglycolipid that the phosphatidyl residue is located at C-6 of the reducing hexosyl residue of the glycolipid moiety and the poly(glycerophosphate) chain at C-6 of the nonreducing one. Together with earlier observations these results complete the evidence for the structural and possibly biosynthetic relationship between lipoteichoic acids and glycerophosphoglycolipids.Key words: lipoteichoic acids, poly(glycerophosphate) lipoteichoic acids, Gram-positive bacteria, bacterial membrane.

scholarly journals Mechanism of persistence of indigenous bifidobacteria under the impact of acetate in the human colon biotope

2021 ◽  
Vol 98 (3) ◽  
pp. 276-282
Author(s):  
O. V. Bukharin ◽  
S. V. Andryuschenko ◽  
N. B. Perunova ◽  
E. V. Ivanova
Keyword(s):  
Acetic Acid ◽  
Ammonium Acetate ◽  
Growth Parameters ◽  
Bifidobacterium Longum ◽  
Human Colon ◽  
Bifidobacterium Bifidum ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
The Impact

Aim. To determine the role of the acetate in the persistence of indigenous bifidobacteria in the colon biotope through the lysozyme resistance in model conditions of the acetylation–deacetylation of peptidoglycan.Materials and methods. The study was performed on 16 strains of the two indigenous bifidobacteria speсies: Bifidobacterium bifidum и Bifidobacterium longum subsp. longum. Bifidobacteria was cultivated in the 0.6% O2 and 9% CO2 atmosphere at the temperature 37ºС in CO2 incubator for 48 hours. The production of the acetate by the bifidobacteria was determined by gas chromatography. The effect of the acetate on the lysozyme resistance of non-indigenous gram-positive bacteria was determined on the Listeria monocytogenes ICIS-280 model strain by the cultivation in LB-Lennox broth with ammonium acetate added in the concentration range matching the concentrations produced by the studied bifidobacteria, in lysozyme serial dilutions at final concentrations 5 μg/ml to 40 μg/ml within 24 hours.Results. It was found that the acetate release of Bifidobacterium longum subsp. longum was on average two times higher that of Bifidobacterium bifidum (27.0 and 14.7 mmol/liter, respectively) and was quite consistent with the concentrations of acetic acid determined in the intestinal contents (up to 50 mmol/liter). Cultivation of bifidobacteria in a medium with lysozyme, ammonium acetate and their combination did not have a significant impact on their growth parameters at the maximum used concentrations of these substances. In the test strain, the addition of ammonium acetate in the range created by bifidobacteria caused a decrease in the minimum inhibitory concentration of lysozyme by more than two times — from 40 μg/ml to less than 20 μg/ml. In the control medium without lysozyme, no inhibition of the growth of the indicator culture was observed up to the maximum concentrations of ammonium acetate.Conclusion. The mechanism of persistence (survival) of indigenous bifidobacteria in the human intestinal biotope has been identified, which is associated with the production of acetic acid at a level that selectively suppresses lysozyme resistance of non-indigenous gram-positive microbiota viareversible deacetylation of peptidoglycan. This allows indigenous bifidobacteria to maintain a stable dominant position in the biotope.

scholarly journals Effects of Antibacterial Peptide F1 on Bacterial Liposome Membrane Integrity

2021 ◽  
Vol 8 ◽  
Author(s):  
Qun Wang ◽  
Bo Peng ◽  
Mingyue Song ◽  
Abdullah ◽  
Jun Li ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Membrane Structure ◽  
Bacterial Membrane ◽  
Phospholipid Membranes ◽  
Phospholipid Membrane ◽  
Gram Positive ◽  
Liposome Membrane ◽  
Gram Negative ◽  
Bacterial Membranes ◽  
Gram Positive Bacteria

Previous studies from our lab have shown that the antimicrobial peptide F1 obtained from the milk fermentation by Lactobacillus paracasei FX-6 derived from Tibetan kefir was different from common antimicrobial peptides; specifically, F1 simultaneously inhibited the growth of Gram-negative and Gram-positive bacteria. Here, we present follow-on work demonstrating that after the antimicrobial peptide F1 acts on either Escherichia coli ATCC 25922 (E. coli) or Staphylococcus aureus ATCC 63589 (S. aureus), their respective bacterial membranes were severely deformed. This deformation allowed leakage of potassium and magnesium ions from the bacterial membrane. The interaction between the antimicrobial peptide F1 and the bacterial membrane was further explored by artificially simulating the bacterial phospholipid membranes and then extracting them. The study results indicated that after the antimicrobial peptide F1 interacted with the bacterial membranes caused significant calcein leakage that had been simulated by different liposomes. Furthermore, transmission electron microscopy observations revealed that the phospholipid membrane structure was destroyed and the liposomes presented aggregation and precipitation. Quartz Crystal Microbalance with Dissipation (QCM-D) results showed that the antimicrobial peptide F1 significantly reduced the quality of liposome membrane and increased their viscoelasticity. Based on the study's findings, the phospholipid membrane particle size was significantly increased, indicating that the antimicrobial peptide F1 had a direct effect on the phospholipid membrane. Conclusively, the antimicrobial peptide F1 destroyed the membrane structure of both Gram-negative and Gram-positive bacteria by destroying the shared components of their respective phospholipid membranes which resulted in leakage of cell contents and subsequently cell death.

Bactericidal effect of gentamicin-induced membrane vesicles derived fromPseudomonas aeruginosaPAO1 on gram-positive bacteria

2002 ◽  
Vol 48 (9) ◽  
pp. 810-820 ◽  
Author(s):  
Kelly L MacDonald ◽  
Terry J Beveridge
Keyword(s):  
Electron Microscopy ◽  
Therapeutic Potential ◽  
Hydrophobic Interaction Chromatography ◽  
Membrane Vesicles ◽  
Bactericidal Effect ◽  
Gram Positive ◽  
Thin Sections ◽  
Gram Negative ◽  
Induced Membrane ◽  
Gram Positive Bacteria

Previous studies have shown that gentamicin-induced membrane vesicles (g-MVs) from Pseudomonas aeruginosa PAO1 possess both the antibiotic (gentamicin) and a potent peptidoglycan hydrolase (PGase; autolysin) that is effective in killing gram-negative pathogens. This present study evaluated the therapeutic potential of g-MVs against four gram-positive bacteria. Bactericidal assays and electron microscopy of thin sections revealed that Bacillus subtilis 168 and Staphylococcus aureus D2C were susceptible to killing mediated by g-MVs, Listeria monocytogenes ATCC 19113 was slightly susceptible, whereas Enterococcus hirae ATCC 9790 was unaffected. g-MVs were generally more effective against the bacteria than was soluble gentamicin, suggesting they could have more killing power than natural membrane vesicles containing no antibiotic. Electron microscopy and hydrophobic interaction chromatography showed that more membrane vesicles (MVs) initially attached to B. subtilis (hydrophilic) than to predominantly hydrophobic E. hirae, L. monocytogenes, and S. aureus. Zymograms containing murein sacculi as an enzyme substrate illustrated that all organisms except E. hirae were sensitive to the 26-kDa autolysin to varying degrees. Peptidoglycan O-acetylation did not influence susceptibility to MV-mediated lysis. Though not universally effective, the g-MV delivery system remains a promising therapeutic alternative for specific gram-positive infections.Key words: gram-negative membrane vesicles, gentamicin, autolysin.

Sign in / Sign up

Export Citation Format

Share Document