scholarly journals Alphavirus and flavivirus infectivity is disrupted by components of the bacterial cell wall

2021 ◽  
Author(s):  
Lana Langendries ◽  
Sofie Jacobs ◽  
Rana Abdelnabi ◽  
Sam Verwimp ◽  
Suzanne Kaptein ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Inhibitory Effect ◽  
Bacterial Cell Wall ◽  
Viral Inhibition ◽  
Virus Particles ◽  
Gram Positive Bacteria ◽  
Complex Microbial Community ◽  
The Impact

The impact of the host microbiome on arbovirus infections is currently not clearly understood. Arboviruses are viruses transmitted through the bites of infected arthropods, predominantly mosquitoes or ticks. The first site of arbovirus inoculation is the biting site in the host skin, which is colonized by a complex microbial community that could possibly influence arbovirus infection. We demonstrated that pre-incubation of arboviruses with certain components of the bacterial cell wall, including lipopolysaccharides (LPS) of some Gram-negative bacteria and lipoteichoic acids or peptidoglycan of certain Gram-positive bacteria, significantly reduced arbovirus infectivity in vitro. This inhibitory effect was observed for arboviruses of different virus families, including chikungunya virus of the Alphavirus genus and Zika virus of the Flavivirus genus, showing that this is a broad phenomenon. A modest inhibitory effect was observed following incubation with a panel of heat-inactivated bacteria, including bacteria residing on the skin. No viral inhibition was observed after pre-incubation of cells with LPS. Furthermore, a virucidal effect of LPS on viral particles was noticed by electron microscopy. Therefore, the main inhibitory mechanism seems to be due to a direct effect on the virus particles. Together, these results suggest that bacteria are able to decrease the infectivity of alphaviruses and flaviviruses.

scholarly journals Rhodomyrtone Accumulates in Bacterial Cell Wall and Cell Membrane and Inhibits the Synthesis of Multiple Cellular Macromolecules in Epidemic Methicillin-Resistant Staphylococcus aureus

Antibiotics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 543
Author(s):  
Ozioma F. Nwabor ◽  
Sukanlaya Leejae ◽  
Supayang P. Voravuthikunchai
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Cell Membrane ◽  
Bacterial Cell ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Treatment Options ◽  
Bacterial Cell Wall ◽  
Methicillin Resistant ◽  
Gram Positive Bacteria ◽  
Inhibitor Compounds

As the burden of antibacterial resistance worsens and treatment options become narrower, rhodomyrtone—a novel natural antibiotic agent with a new antibacterial mechanism—could replace existing antibiotics for the treatment of infections caused by multi-drug resistant Gram-positive bacteria. In this study, rhodomyrtone was detected within the cell by means of an easy an inexpensive method. The antibacterial effects of rhodomyrtone were investigated on epidemic methicillin-resistant Staphylococcus aureus. Thin-layer chromatography demonstrated the entrapment and accumulation of rhodomyrtone within the bacterial cell wall and cell membrane. The incorporation of radiolabelled precursors revealed that rhodomyrtone inhibited the synthesis of macromolecules including DNA, RNA, proteins, the cell wall, and lipids. Following the treatment with rhodomyrtone at MIC (0.5–1 µg/mL), the synthesis of all macromolecules was significantly inhibited (p ≤ 0.05) after 4 h. Inhibition of macromolecule synthesis was demonstrated after 30 min at a higher concentration of rhodomyrtone (4× MIC), comparable to standard inhibitor compounds. In contrast, rhodomyrtone did not affect lipase activity in staphylococci—both epidemic methicillin-resistant S. aureus and S. aureus ATCC 29213. Interfering with the synthesis of multiple macromolecules is thought to be one of the antibacterial mechanisms of rhodomyrtone.

Role of kallikrein-kinin system in pathogenesis of bacterial cell wall-induced inflammation

1991 ◽  
Vol 260 (2) ◽  
pp. G213-G219 ◽  
Author(s):  
R. A. DeLa Cadena ◽  
K. J. Laskin ◽  
R. A. Pixley ◽  
R. B. Sartor ◽  
J. H. Schwab ◽  
...  
Keyword(s):  
Cell Wall ◽  
Acute Phase ◽  
Bacterial Cell ◽  
Chronic Phase ◽  
Bacterial Cell Wall ◽  
Kinin System ◽  
Kallikrein Kinin System ◽  
Bacterial Products

The plasma kallikrein-kinin system is activated in Gram-negative sepsis and typhoid fever, two diseases in which bacterial products have been shown to initiate inflammation. Because a single intraperitoneal injection of bacterial cell wall peptidoglycan-polysaccharide polymers from group A steptococci (PG-APS) into a Lewis rat produces a syndrome of relapsing polyarthritis and anemia, we investigated changes in the role of the kallikrein-kinin system in this model of inflammation. Coagulation studies after injection of PG-APS revealed an immediate and persistent decrease in prekallikrein levels. High-molecular-weight kininogen levels decreased significantly during the acute phase and correlated with the severity of arthritis. Factor XI levels were decreased only during the acute phase. Antithrombin III levels remained unchanged, indicating that neither decreased hepatic synthesis nor disseminated intravascular coagulation caused the decreased plasma contact factors. Plasma T-kininogen (an acute phase protein) was significantly elevated during the chronic phase. PG-APS failed to activate the contact system in vitro. Thus the kallikrein-kinin system plays an important role in this experimental model of inflammation, suggesting that activation of this system may play a role in the pathogenesis of inflammatory bowel disease and rheumatoid arthritis in which bacterial products might be etiologically important.

SEQUENCE STUDIES ON BACTERIAL CELL WALL PEPTIDES

1964 ◽  
Vol 42 (11) ◽  
pp. 1553-1559 ◽  
Author(s):  
D. Jušić ◽  
C. Roy ◽  
R. W. Watson
Keyword(s):  
Cell Wall ◽  
Paper Chromatography ◽  
High Voltage ◽  
Bacterial Cell ◽  
Paper Electrophoresis ◽  
Bacterial Cell Wall ◽  
Molar Ratios

Peptides from partial acid hydrolysates of purified mucopeptide from Aerobacter cloacae NRC 492 were isolated by a combination of high-voltage paper electrophoresis and paper chromatography. Three dipeptides (L-ala.D-glu, D-glu.meso-Dap, and meso-Dap.D-ala), two tripeptides (ala.D-glu.meso-Dap and D-glu.meso-Dap.ala, i.e. D-glutamyl.meso-diaminopimelyl.alanine), and a tetrapeptide were partially characterized. Molar ratios, sequence, and optical configurations in a tripeptide from the wall corresponded with those in a uridine diphospho muramyl tripeptide from penicillin-treated cells of the same organism and with those of a tripeptide synthesized in vitro by enzymes from cell sonicates.

The Potency of Catechin from Gambir (Uncaria gambir Roxb.) as a Natural Inhibitor of MurA (1UAE) Enzyme: In vitro and In silico studies

2020 ◽  
Vol 17 (12) ◽  
pp. 1531-1537
Author(s):  
Bella Riyana ◽  
Desi Harneti Putri Huspa ◽  
Mieke Hemiawati Satari ◽  
Dikdik Kurnia
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
In Silico ◽  
Bacterial Activity ◽  
Bacterial Cell Wall ◽  
Resistant Bacteria ◽  
In Silico Studies ◽  
In Silico Study ◽  
Natural Inhibitor

Background: Currently, infectious diseases caused by pathogenic and resistant bacteria are more challenging for anti-bacterial drug discovery. The discovery of new anti-bacterial agents developed in many mechanisms includes disruption of the bacterial cell wall formations. The MurA is a key enzyme contributing to the first step of bacterial peptidoglycan biosynthesis and is, therefore, proposed as an effective bactericidal target. Objective: The purpose of this research is to identify anti-bacterial compounds from U. gambir Roxb and to predict the potential inhibitory activities against murA enzyme by in silico study. Materials and Methods: Investigation and discovery of new inhibitors of MurA enzyme were conducted on the medicinal plant of Gambir (Uncaria gambir Roxb) and those that reportedly contained anti-bacterial agents. The anti-bacterial compounds were isolated by combinations of chromatography methods guided by anti-bacterial activity against bacteria of E. faecalis, S. mutans, and S. sanguinis. The structures of active compounds were characterized by spectroscopic methods, and the anti-bacterial activity was evaluated by the microdilution method (in vitro) combined with molecular docking of the MurA enzyme (in silico). Results: The anti-bacterial flavonoids of catechin were isolated from U. gambir Roxb with MIC values of 6250 and 12500 ppm, respectively, against S. sanguinis and E. faecalis. The in silico study showed that catechin has a binding affinity of -8.5 Kcal/mol to MurA which is higher than fosfomycin as a positive control. Conclusions: The catechin is predicted to have potential as a new natural inhibitor of the MurA enzyme to inhibit bacterial cell wall biosynthesis.

scholarly journals Antibacterial efficacy of Jackfruit rag extract against clinically important pathogens and validation of its antimicrobial activity in Shigella dysenteriae infected Drosophila melanogaster infection model

2020 ◽  
Author(s):  
NV Dhwani ◽  
Gayathri Raju ◽  
Sumi E Mathew ◽  
Gaurav Baranwal ◽  
Shivakumar B Shivaram ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Antibacterial Property ◽  
Mouse Fibroblast ◽  
Bacterial Cell Wall ◽  
Shigella Dysenteriae ◽  
Infection Model ◽  
Bacterial Cells

AbstractThe aim of this study was to determine the antibacterial property of extract derived from a part of the Jackfruit called ‘rag’, that is generally considered as fruit waste. Morpho-physical characterization of the Jackfruit rag extract (JFRE) was performed using gas-chromatography, where peaks indicative of furfural; pentanoic acid; and hexadecanoic acid were observed. In vitro biocompatibility of JFRE was performed using the MTT assay, which showed comparable cellular viability between extract-treated and untreated mouse fibroblast cells. Agar well disc diffusion assay exhibited JFRE induced zones of inhibition for a wide variety of laboratory and clinical strains of gram-positive and gram-negative bacteria. Analysis of electron microscope images of bacterial cells suggests that JFRE induces cell death by disintegration of the bacterial cell wall and precipitating intracytoplasmic clumping. The antibacterial activity of the JFREs was further validated in vivo using Shigella dysenteriae infected fly model, where JFRE pre-fed flies infected with S. dysenteriae had significantly reduced mortality compared to controls. JFRE demonstrates broad antibacterial property, both in vitro and in vivo, possibly by its activity on bacterial cell wall. This study highlights the importance of exploring alternative sources of antibacterial compounds, especially from plant-derived waste, that could provide economical and effective solutions to current challenges in antimicrobial therapy.

Infectious disease

2019 ◽  
Author(s):  
Stevan R. Emmett ◽  
Nicola Hill ◽  
Federico Dajas-Bailador
Keyword(s):  
Cell Wall ◽  
Protein Synthesis ◽  
Nucleic Acid ◽  
Outer Membrane ◽  
Bacterial Cell ◽  
Bacterial Cell Wall ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Antibiotics include an extensive range of agents able to kill or prevent reproduction of bacteria in the body, without being overly toxic to the patient. Traditionally derived from living organisms, most are now chemically synthesized and act to disrupt the integrity of the bacterial cell wall, or penetrate the cell and disrupt protein synthesis or nucleic acid replication. Typically, bacteria are identified according to their ap­pearance under the microscope depending on shape and response to the Gram stain test. Further identification is obtained by growth characteristics on various types of culture media, based on broth or agar, biochemical and immunological profiles. Further testing on broth or agar determines antibiotic sensitivity to guide on anti­biotic therapy in individual patients. This process can take 24– 48 hours to culture and a further 24– 48 hours to measure sensitivities. Increasingly, new technology, e.g. Matrix Assisted Laser Desorption Ionization— Time of Flight (MALDI- TOF) and nucleic acid amplification as­says, are being used to provide more rapid identification. The Gram classification, however, is still widely referred to as it differentiates bacteria by the presence or absence of the outer lipid membrane (see Figure 11.1), a fundamental characteristic that influences antibiotic management. Antimicrobial agents rely on selective action exploiting genetic differences between bacterial and eukaryotic cells. They target bacterial cell wall synthesis, bacterial protein synthesis, microbial DNA or RNA synthesis, by acting on bacterial cell metabolic pathways or by inhibiting the ac­tion of a bacterial toxin (see Table 11.1). Both Gram- positive and Gram- negative bacteria possess a rigid cell wall able to protect the bacteria from varying osmotic pressures (Figure 11.1). Peptidoglycan gives the cell wall its rigidity and is composed of a glycan chain of complex alternating carbohydrates, N- acetylglucosamide (N- ATG), and N- acetylmurcarinic acid (N- ATM), that are cross- linked by peptide (or glycine) chains. In Gram-positive bacteria, the cell wall contains multiple peptido­glycan layers, interspersed with teichoic acids, whereas Gram- negative bacteria contain only one or two peptido­glycan layers that are surrounded by an outer membrane attached by lipoproteins. The outer membrane contains porins (which regulate transport of substances into and out of the cell), lipopolysaccharides, and outer proteins in a phospholipid bilayer. For both Gram- negative and Gram-positive bacteria, peptidoglycan synthesis involves about 30 bacterial enzymes acting over three stages. Since the cell wall is unique to bacteria, it makes a suitable target for antibiotic therapy.

Potential Fatty Acid as Antibacterial Agent against Oral Bacteria of Streptococcus mutans and Streptococcus sanguinis from Basil (Ocimum americanum): In vitro and in silico studies.

2020 ◽  
Vol 17 ◽  
Author(s):  
Yetty Herdiyati ◽  
Yonada Astrid ◽  
Aldina Amalia Nur Shadrina ◽  
Ika Wiani ◽  
Mieke Hemiawati Satari ◽  
...  
Keyword(s):  
Cell Wall ◽  
Antibacterial Activity ◽  
Streptococcus Mutans ◽  
Lauric Acid ◽  
Bacterial Cell ◽  
In Silico ◽  
Antibacterial Agent ◽  
Bacterial Cell Wall ◽  
Ocimum Americanum

Background: Streptococcus mutans and Streptococcus sanguinis are Gram-positive bacteria that cause dental caries. The MurA enzyme is a catalyst in the formation of peptidoglycan in the bacterial cell wall making it ideal as an antibacterial target. Basil (Ocimum americanum) is an edible plant medicine that diverse, very widely spreading, used as herbal for a long time, and it was reported to have pharmacology effect as antibacterial activity. The purpose of this study is to identify antibacterial compounds from O. americanum and analyze their inhibition activity to the MurA enzyme. Methods: Fresh leaves from O. americanum extracted with n-hexane and purified by a combination of column chromatography on normal and reverse phase together with guided by in vitro bioactivity assay against S. mutans ATCC 25175 and S. sanguinis ATCC 10556, respectively, while in silico molecular docking simulation of lauric acid (1) using PyRx 0.8. Results: The structure determination of antibacterial compound by spectroscopic methods resulted in an active compound 1 as lauric acid. The in vitro evaluation of antibacterial activity compound 1 showed the MIC and MBC of 78.13 & 156.3 ppm and 1250 & 2500 ppm against S. sanguinis and in S. mutans, respectively. Further analysis in silico evaluation as MurA Enzyme inhibitor, lauric acid (1) has a binding affinity of -5.2 Kcal/mol those higher than fosfomycin. Conclusion: The lauric acid has potency as a new natural antibacterial agent through the MurA inhibition in bacterial cell wall biosynthesis.

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