scholarly journals Affinities of β-Lactams for Penicillin Binding Proteins of Chlamydia trachomatis and Their Antichlamydial Activities

2001 ◽  
Vol 45 (1) ◽  
pp. 303-305 ◽  
Author(s):  
Christopher Storey ◽  
Ian Chopra
Keyword(s):  
Chlamydia Trachomatis ◽  
Binding Proteins ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
The Other ◽  
Binding Affinities ◽  
Penicillin Binding Proteins

ABSTRACT Binding affinities of β-lactam antibiotics for the three penicillin binding proteins (PBPs) from Chlamydia trachomatis were determined in vitro and compared with their antichlamydial activities. Mecillinam selectively inhibited PBP1, with a 50% inhibitory concentration for PBP1 binding (0.2 μg/ml) similar to the MIC (0.1 μg/ml) and minimum bactericidal concentration (0.25 μg/ml). Although the other β-lactams inhibited a wider range of PBPs than mecillinam, their antichlamydial activities were inferior to that of mecillinam.

scholarly journals Antibacterial and Hemolytic Activity of Crotalus triseriatus and Crotalus ravus Venom

Animals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 281
Author(s):  
Adrian Zaragoza-Bastida ◽  
Saudy Consepcion Flores-Aguilar ◽  
Liliana Mireya Aguilar-Castro ◽  
Ana Lizet Morales-Ubaldo ◽  
Benjamín Valladares-Carranza ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Minimum Inhibitory Concentration ◽  
Hemolytic Activity ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
The Other ◽  
Medical Treatments ◽  
First Time

Rattlesnakes have venoms with a complex toxin mixture comprised of polypeptides and proteins. Previous studies have shown that some of these polypeptides are of high value for the development of new medical treatments. The aim of the present study is to evaluate, in vitro, the antibacterial and hemolytic activity of Crotalus triseriatus and Crotalus ravus venoms. A direct field search was conducted to obtain Crotalus triseriatus and Crotalus ravus venom samples. These were evaluated to determine their antibacterial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa through the techniques of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). Hemolytic activity was also determined. Antibacterial activity was determined for treatments (Crotalus triseriatus 2) CT2 and (Crotalus ravus 3) CR3, obtaining a Minimum Inhibitory Concentration of 50 µg/mL and a Minimum Bactericidal Concentration of 100 µg/mL against Pseudomonas aeruginosa. CT1 (Crotalus triseriatus 1), CT2, and CR3 presented hemolytic activity; on the other hand, Crotalus ravus 4 (CR4) did not show hemolytic activity. The results of the present study indicate for the first time that Crotalus triseriatus and Crotalus ravus venoms contain some bioactive compounds with bactericidal activity against Pseudomonas aeruginosa which could be used as alternative treatment in diseases caused by this pathogenic bacterium.

Gene Disruption Studies of Penicillin-Binding Proteins 1a, 1b, and 2a in Streptococcus pneumoniae

1999 ◽  
Vol 181 (20) ◽  
pp. 6552-6555 ◽  
Author(s):  
JoAnn Hoskins ◽  
Patti Matsushima ◽  
Deborah L. Mullen ◽  
Joseph Tang ◽  
Genshi Zhao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Streptococcus Pneumoniae ◽  
Gene Disruption ◽  
Binding Proteins ◽  
The Other ◽  
Penicillin Binding Protein ◽  
Disruption Mutant ◽  
Penicillin Binding Proteins ◽  
Genes Encoding

ABSTRACT The effects of inactivation of the genes encoding penicillin-binding protein 1a (PBP1a), PBP1b, and PBP2a inStreptococcus pneumoniae were examined. Insertional mutants did not exhibit detectable changes in growth rate or morphology, although a pbp1a pbp1b double-disruption mutant grew more slowly than its parent did. Attempts to generate a pbp1a pbp2a double-disruption mutant failed. The pbp2amutants, but not the other mutants, were more sensitive to moenomycin, a transglycosylase inhibitor. These observations suggest that individually the pbp1a, pbp1b, andpbp2a genes are dispensable but that eitherpbp1a or pbp2a is required for growth in vitro. These results also suggest that PBP2a is a functional transglycosylase in S. pneumoniae.

The in vitro efficacy of neutral electrolysed water and povidone-iodine against CRS-associated biofilms

2021 ◽  
Vol 0 (0) ◽  
pp. 0-0
Author(s):  
C.A. Lux ◽  
K. Biswas ◽  
M.W. Taylor ◽  
R.G. Douglas
Keyword(s):  
Inhibitory Concentration ◽  
Povidone Iodine ◽  
Minimum Bactericidal Concentration ◽  
Treatment Options ◽  
Antimicrobial Treatment ◽  
Biofilm Reactor ◽  
Bacterial Biofilms ◽  
Antibiofilm Activity

Background: Despite best medical and surgical practice, some cases of chronic rhinosinusitis (CRS) can remain recalcitrant. Bacterial biofilms have been associated with the recalcitrance of sinonasal inflammation. Biofilms are highly resistant to commonly prescribed antibiotics. Accordingly, more effective antimicrobial treatment options are needed to treat refractory CRS. The aim of this study was to determine the in vitro efficacy of neutral electrolysed water (NEW) and povidone-iodine (PVI) against CRS-associated Staphylococcus aureus biofilms. Methods: Mature S. aureus biofilms were grown in a Centre for Disease Control (CDC) biofilm reactor. The antimicrobial activity of NEW, PVI and doxycycline was determined for both planktonic and biofilm cultures of a clinical S. aureus isolate using minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) assays. Results: MICs and MBCs were determined for all antimicrobials. MBC values were similar to MICs for both antiseptics, but doxycycline MBCs were significantly higher than the associated MICs. Biofilms were highly resistant to NEW and doxycycline. The MBEC for doxycycline was between 500 and 1000 µg/mL. NEW was ineffective against biofilms and no MBEC could be determined. In contrast, a concentration of 10% of the commercial PVI solution (10 mg/mL PVI) led to effective eradication of mature biofilms. Conclusion: In this study, only PVI showed promising antibiofilm activity at physiological concentrations. The in vivo efficacy of PVI warrants further investigation of its potential as a treatment for recalcitrant CRS.

scholarly journals THE EFFECT OF PROPOLIS EXTRACT AND PROPOLIS CANDIES ON THE GROWTH OF AGGREGATIBACTER ACTINOMYCETEMCOMITANS ATCC 43718

2017 ◽  
Vol 10 (17) ◽  
pp. 26
Author(s):  
Khodijah Khodijah ◽  
Ratna Farida ◽  
Nurtami Soedarsono
Keyword(s):  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Aggregatibacter Actinomycetemcomitans ◽  
Spectrophotometric Analysis ◽  
Propolis Extract ◽  
Post Exposure ◽  
Colony Forming Units

Objective: This experiment aimed to analyze the effect of propolis extract and propolis containing candies on the growth of Aggregatibacter actinomycetemcomitans using spectrophotometric analysis and colony-forming units (CFU) counts.Methods: After A. actinomycetemcomitans were exposed to propolis extract and candies, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined with spectrophotometry and post-exposure colony counting.Results: The MIC of propolis extract against A. actinomycetemcomitans was determined to be 10%, and the MBC was 20%. A decrease in the total CFU count of A. actinomycetemcomitans was observed after propolis extract and candy exposure.Conclusions: Propolis extract and propolis candies were effective in inhibiting the growth of A. actinomycetemcomitans ATCC 43718 in vitro.

scholarly journals DIFFERENCE BETWEEN ANTIMICROBIAL EFFECTS OF PAPACARIE AND PAPAIN ON STREPTOCOCCUS MUTANS IN VITRO

2019 ◽  
pp. 79-83
Author(s):  
TITTY SULIANTI ◽  
NILAKESUMA DJAUHARI ◽  
BAMBANG NURSASONGKO
Keyword(s):  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Zone Of Inhibition ◽  
Antimicrobial Effects ◽  
Treatment Groups ◽  
Group Control ◽  
Caries Removal ◽  
And Diffusion ◽  
Better Than

Objective: The aim is to compare the antimicrobial effects of papain and Papacarie with dilution and diffusion tests.Methods: There were two treatment groups and one Group control. The treatment group received papain and Papacarie, and the control groupreceived chlorhexidine, in five liquids with different concentrations of 0.5%, 0.25%, 0.125%, 0.0625%, and 0.03%. The dilution and diffusion testswere used to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and zone of inhibition for eachtreatment material.Results: MICs of papain and Papacarie were 12.5%, indicating that at a concentration of 12.5%, the material can inhibit the growth of Streptococcusmutans. Papain does not have an MBC value but the Papacarie has an MBC at 25%, which indicating that at a concentration of 25%, Papacarie hasbactericidal effects on S. mutans. The zone of inhibition of papain was lower than Papacarie.Conclusion: Based on chemomechanical caries removal materials, the antimicrobial effects of Papacarie were better than those of papain.

scholarly journals EVALUATION OF ANTIBACTERIAL RESISTANCE OF BIOFILM FORMS OF AVIAN SALMONELLA GALLINARUM TO FLUOROQUINOLONES

2018 ◽  
Author(s):  
Kumar Kamashi ◽  
Mr. Honnegowda ◽  
Mayanna Asha ◽  
Chandrakala Ms.
Keyword(s):  
Pathogenic Bacteria ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Bacterial Biofilms ◽  
Dilution Method ◽  
Post Inoculation ◽  
Antibacterial Resistance ◽  
Salmonella Gallinarum ◽  
Broth Dilution

Antimicrobial resistance is a growing concern worldwide. The indiscriminate use of antibiotics for a period of time has led to the emergence of antibiotic resistance in pathogenic bacteria. The present study was designed to evaluate the antibacterial efficacy of fluoroquinolone drugs, ciprofloxacin, enrofloxacin, moxifloxacin, sparfloxacin, norfloxacin, pefloxacin and ofloxacin against avian Salmonella gallinarum bacterial biofilms. The study parameters, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and biofilm elimination concentration (BEC) were determined on days 1, 3, 7, 10, 14 and 20 post inoculation for the planktonic (free) and biofilm cells of S. gallinarum by macro broth dilution method. The MIC and MBC values determined on days 1, 3, 7, 10, 14 and 20 for each of the fluoroquinolone drugs against the planktonic and biofilm forms of avian S. gallinarum were found to be non-significant. BEC values determined against the biofilm forms of S. gallinarum during the study period were found to be non-significant among the tested fluoroquinolones. The results of the present study demonstrated that fluoroquinolone drugs were effective in vitro against both the planktonic and biofilm forms of avian S. gallinarum.

Dynamic localization of penicillin-binding proteins during spore development in Bacillus subtilis

Microbiology ◽  
2005 ◽  
Vol 151 (3) ◽  
pp. 999-1012 ◽  
Author(s):  
Dirk-Jan Scheffers
Keyword(s):  
Bacillus Subtilis ◽  
Green Fluorescent Protein ◽  
Binding Proteins ◽  
Cytoplasmic Membrane ◽  
Fluorescent Protein ◽  
Spore Formation ◽  
The Other ◽  
Spore Development ◽  
Penicillin Binding Proteins ◽  
Green Fluorescent

During Bacillus subtilis spore formation, many membrane proteins that function in spore development localize to the prespore septum and, subsequently, to the outer prespore membrane. Recently, it was shown that the cell-division-specific penicillin-binding proteins (PBPs) 1 and 2b localize to the asymmetric prespore septum. Here, the author studied the localization of other PBPs, fused to green fluorescent protein (GFP), during spore formation. Fusions to PBPs 4, 2c, 2d, 2a, 3, H, 4b, 5, 4a, 4* and X were expressed during vegetative growth, and their localization was monitored during sporulation. Of these PBPs, 2c, 2d, 4b and 4* have been implicated as having a function in sporulation. It was found that PBP2c, 2d and X changed their localization, while the other PBPs tested were not affected. The putative endopeptidase PbpX appears to spiral out in a pattern that resembles FtsZ redistribution during sporulation, but a pbpX knockout strain had no distinguishable phenotype. PBP2c and 2d localize to the prespore septum and follow the membrane during engulfment, and so are redistributed to the prespore membrane. A similar pattern was observed when GFP–PBP2c was expressed in the mother cell from a sporulation-specific promoter. This work shows that various PBPs known to function during sporulation are redistributed from the cytoplasmic membrane to the prespore.

scholarly journals Susceptibility of Methicillin-Resistant Staphylococcus aureus to Five Quinazolinone Antibacterials

2019 ◽  
Vol 64 (1) ◽  
Author(s):  
Sara Ceballos ◽  
Choon Kim ◽  
Yuanyuan Qian ◽  
Shahriar Mobashery ◽  
Mayland Chang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Amino Acid ◽  
Binding Proteins ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistant ◽  
Content Type ◽  
Penicillin Binding Proteins

ABSTRACT The in vitro activities of five quinazolinone antibacterials, compounds Q1 to Q5, were tested against 210 strains of methicillin-resistant Staphylococcus aureus (MRSA). The MIC50/MIC90 values (in μg/ml) were as follows: Q1, 0.5/2; Q2, 1/4; Q3, 2/4; Q4, 0.06/0.25; and Q5, 0.125/0.5. Several strains with high MIC values (from 8 to >32 μg/ml) for some of these compounds exhibited amino acid changes in the penicillin-binding proteins, which are targeted by these antibacterials.

scholarly journals Microwave-Assisted Synthesis of Some Potential Bioactive Imidazolium-Based Room-Temperature Ionic Liquids

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1727 ◽  
Author(s):  
Ahmed Albalawi ◽  
Wael El-Sayed ◽  
Ateyatallah Aljuhani ◽  
Saud Almutairi ◽  
Nadjet Rezki ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Room Temperature ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Alkyl Chain ◽  
Phenyl Group ◽  
Room Temperature Ionic Liquids ◽  
Microwave Assisted Synthesis ◽  
Conventional Procedure

An environmentally-friendly and easy synthesis of a series of novel functionalized imidazolium-based ionic liquids (ILs) is described under both the conventional procedure and microwave irradiation. The structures of newly synthesized room-temperature ionic liquids (RTILs) were established by different spectral analyses. All ILs (1–14) were screened for their in vitro antimicrobial activity against a panel of clinically isolated bacteria. The results of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) showed that some of the tested ILs are very promising anti-bacterial agents especially those containing an alkyl chain with a phenyl group (most notably 1, 2, 12, and 13).

In-vitro Antibacterial Effects of Aqueous, Ethanolic, Methanolic, Acetone and Hydro Ethanolic Extracts of Achillea Millefolium on Standard Klebsiella, S. pyogenes, and Oral Bacterias Strains

2020 ◽  
Author(s):  
Negar Fallah ◽  
Sanaz Namazi ◽  
Negar Balmeh ◽  
Samira Mahmoudi ◽  
Fereshteh Mirzaei Poor
Keyword(s):  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Methanolic Extract ◽  
Growth Zone ◽  
Achillea Millefolium ◽  
Antibacterial Effects ◽  
Millipore Filter ◽  
Antimicrobial Effects ◽  
Aerial Parts

Introduction: So far, a lot of attempts have been carried out to find antimicrobial compounds. In this study, it was also tried to investigate the antibacterial effects of Achillea millefolium on standard Klebsiella, S. pyogenes, and oral bacterias strain. Material and Methods: The aerial parts of Achillea millefolium were used and the aqueous, ethanolic, methanolic, acetone and hydroethanolic extracts were prepared. After the preparation of standard strains of Klebsiella, S. pyogenes, and oral bacterias and sterilization of extracts by the Millipore filter, the antibacterial effects of these extracts on the mentioned microorganisms were assessed by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and well diffusion at the concentration 50 mg/ml. The test was repeated three times for each bacterium. Results: It was exposed that aqueous extract of Achillea millefolium had the most distinguished antimicrobial effects against all studied strains and methanolic extract had antimicrobial effects only on S. pyogenes. MIC and MBC of effective extracts were the basic concentration (50mg/ml), and non-growth zone was not observed in other serial dilution in case of all bacteria. Conclusion: The Achillea millefolium can be admitted as an antibacterial medicinal herb. Thus, it can be concluded that after evaluating their effects in vitro, Achillea millefolium can be utilized as an alternative to the routine chemical drugs.

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