Structure‐activity trend analysis between amino‐acids and minimal inhibitory concentration of antimicrobial peptides

2021 ◽  
Author(s):  
Abdelmajid Zouhir ◽  
Nabil Semmar
Keyword(s):  
Amino Acids ◽  
Antimicrobial Peptides ◽  
Trend Analysis ◽  
Minimal Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Structure Activity

Activated Platelet-Derived Antimicrobial Peptides Exhibit Virucidal Properties against Vaccinia Virus in Plasma.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2118-2118
Author(s):  
Krishna Mohan V. Ketha ◽  
Shilpakala Sainath Rao ◽  
Chintamani D Atreya
Keyword(s):  
Antimicrobial Peptides ◽  
Vaccinia Virus ◽  
Minimal Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Human Platelet ◽  
Transfusion Medicine ◽  
Spiked Sample ◽  
Log Reduction ◽  
Virus Contamination ◽  
Viral Titers

Abstract Abstract 2118 Poster Board II-95 Introduction: Contamination of blood and blood components by bacteria, virus, fungi and parasites is a major safety risk in transfusion medicine. While there has been a tremendous success in inactivating virus contamination in blood products through UV-irradiation, new and novel proof-of-concepts for microbial reduction that enhance risk to benefit ratio of the treated products are still a public health need in transfusion medicine. In the present study, we tested four novel synthetic antimicrobial peptides originating from thrombin-induced human platelet-derived antimicrobial proteins named PD1-PD4 against an enveloped virus, Vaccinia Virus (VV) spiked in plasma as a model system. We have recently shown these peptides to be useful in reducing bacterial burden in plasma and platelets. These short synthetic peptides are human platelet-derived and known to cause no immune response in humans and non-hemolytic in nature as reported by others. Methods: The PD1-PD4 peptides were tested on plasma samples spiked with 10-fold dilutions of the wild-type lab strain of Vaccinia Virus (WR strain). Each spiked sample was pre-incubated individually with a peptide (PD1-PD4) for 1 hour at 37°C. Spiked sample without any peptide was included as control. A cell culture-based standard plaque reduction assay method was utilized to monitor the virucidal effectiveness of the peptides. Minimal inhibitory concentration of the peptides was also estimated by testing the peptides at doubling dilutions of 100 μg/ml, 50 μg/ml, 25 μg/ml and 12.5 μg/ml concentrations. Results: Our analysis revealed that peptides PD3 and PD4 were potent against vaccinia virus resulting in reduction of viral titers in the plasma. PD3 peptide demonstrated the highest virucidal activity by bringing about a 2-log reduction of VV titers. PD4 peptide treatment resulted in a 1-1.5 log reduction in viral titers. The minimal inhibitory concentration analysis revealed that at 50 μg/ml concentration both the PD3 and PD4 were able to bring about a log reduction in viral titers. Conclusion: The present study reports a novel antiviral agent for reducing vaccinia virus contamination in plasma. Safety profiles of these peptides as reported by others in conjunction with our current studies, provide a new proof-of-concept that could be useful as safer and simpler alternatives to the viral reduction agents in transfusion medicine. The findings and conclusions in this abstract have not been formally disseminated by the Food and Drug Administration and should not be construed to represent any Agency determination or policy. Disclosures: No relevant conflicts of interest to declare.

Predicting the Minimal Inhibitory Concentration for Antimicrobial Peptides with Rana-Box Domain

2015 ◽  
Vol 55 (10) ◽  
pp. 2275-2287 ◽  
Author(s):  
Mara Kozić ◽  
Damir Vukičević ◽  
Juraj Simunić ◽  
Tomislav Rončević ◽  
Nikolinka Antcheva ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Minimal Inhibitory Concentration ◽  
Inhibitory Concentration

Relationship Between Drug Structure and Minimal Inhibitory Concentration Value Used for Acceptable Daily Intake Analysis

2014 ◽  
Vol 33 (6) ◽  
pp. 490-497
Author(s):  
Tomasz Grabowski ◽  
Jerzy Jan Jaroszewski ◽  
Shayne Cox Gad ◽  
Marcin Feder
Keyword(s):  
Minimal Inhibitory Concentration ◽  
Physicochemical Parameters ◽  
Chemical Structure ◽  
Inhibitory Concentration ◽  
Daily Intake ◽  
Bacterial Strains ◽  
Rigorous Evaluation ◽  
Structure Activity ◽  
Derivatives Of

The minimal inhibitory concentration (MIC) of an antimicrobial agent for a microbial population (MIC50, obs and MIC90, obs) is an interpolated value determined for antibacterial drugs by in vitro methods. Many studies have tried to determine the correlation between the MIC50, obs or MIC90, obs value and the physicochemical parameters to allow quantitaive structure activity relationship (QSAR) predictions of efficacy. A rigorous evaluation of approaches to this problem is presented here. In order to find a correlation between chemical structure and the derivatives of the MIC values for 9 indicatory bacterial strains, it is necessary to employ a number of physicochemical parameters in combination. Only an arithmetic expression composed of many features illustrating the chemical structure of the molecule can be linked to the ƒMIC50, obs value. This article demonstrated that, despite the complexity of the MIC value used as the end point, it is possible to validate the model in a limited extent.

scholarly journals Antiplasmodial Activity of Lauryl-Lysine Oligomers

2007 ◽  
Vol 51 (5) ◽  
pp. 1753-1759 ◽  
Author(s):  
I. Radzishevsky ◽  
M. Krugliak ◽  
H. Ginsburg ◽  
A. Mor
Keyword(s):  
Antimicrobial Peptides ◽  
Self Assembly ◽  
Inhibitory Concentration ◽  
Antimalarial Activity ◽  
New Drugs ◽  
Developmental Cycle ◽  
Compound A ◽  
Structure Activity ◽  
Full Effect ◽  
Further Development

ABSTRACT The ever evolving resistance of the most virulent malaria parasite, Plasmodium falciparum, to antimalarials necessitates the continuous development of new drugs. Our previous analysis of the antimalarial activities of the hemolytic antimicrobial peptides dermaseptins and their acylated derivatives implicated the importance of hydrophobicity and charge for drug action. Following these findings, an oligoacyllysine (OAK) tetramer designed to mimic the characteristics of dermaseptin was synthesized and assessed for its antimalarial activity in cultures of P. falciparum. The tetramer inhibited the growth of different plasmodial strains at low micromolar concentrations (mean 50% inhibitory concentration [IC50], 1.8 μM). A structure-activity relationship study involving eight derivatives unraveled smaller, more potent OAK analogs (IC50s, 0.08 to 0.14 μM). The most potent analogs were the most selective, with selectivity ratios of 3 orders of magnitude. Selectivity was strongly influenced by the self-assembly properties resulting from interactions between hydrophobic OAKs, as has been observed with conventional antimicrobial peptides. Further investigations performed with a representative OAK revealed that the ring and trophozoite stages of the parasite developmental cycle were equally sensitive to the compound. A shortcoming of the tested compound was the need for long incubation times in order for it to exert its full effect. Nevertheless, the encouraging results obtained in this study regarding the efficiency and selectivity of some compounds establish them as leads for further development.

Nồng độ ức chế tối thiểu (Minimal Inhibitory Concentration - MIC) của một số loại kháng sinh đến vi khuẩn phân lập được từ cá dìa thương phẩm mắc bệnh lở loét (Siganus guttatus, Bloch, 1787)

2015 ◽  
Vol 104 (5) ◽  
Author(s):  
Lê Văn Bảo Duy ◽  
Dương Thị Thủy ◽  
Nguyễn Ngọc Phước ◽  
Trương Thị Hoa ◽  
Nguyễn Đức Quỳnh Anh
Keyword(s):  
Minimal Inhibitory Concentration ◽  
Vibrio Parahaemolyticus ◽  
Inhibitory Concentration ◽  
Vibrio Tubiashii

Nghiên cứu được tiến hành nhằm xác định nồng độ ức chế tối thiểu (Minimal Inhibitory Concentration - MIC) của một số loại kháng sinh đến vi khuẩn phân lập được từ cá dìa thương phẩm mắc bệnh lở loét (Siganus guttatus). Từ kết quả phân lập định danh cho thấy 2 chủng Vibrio parahaemolyticus VPMP22 và Vibrio tubiashii ATCC 19109 có mặt trên các vết lở loét ở cá dìa thương phẩm. Kết quả thử nghiệm MIC cho thấy các loại kháng sinh Cefuroxim, Cefotaxim, Tetracycline, Erythromicin, Rifamicin có nồng độ ức chế vi khuẩn Vibrio parahaemolyticus VPMP22 tốt nhất dưới 0.21 µg/ml. Các kháng sinh có Cefuroxim, Cefotaxim, Oxytetraciline, Erythromicin, Trimethoprim nồng độ ức chế vi khuẩn Vibrio tubiashii ATCC 19109 tốt nhất dưới 1.25 µg/ml. Penicillin có nồng độ ức chế tối thiểu cao nhất đối với cả 2 chủng vi khuẩn trên (80 µg/ml), cho thấy 2 chủng vi khuẩn trên đã có sự kháng thuốc đối với loại kháng sinh này. Do đó, trong phòng trị bệnh lở loét trên cá dìa nên sử dụng Cefuroxim và Cefotaxim để có hiệu quả cao nhất trong phòng trị bệnh.

Antimicrobial Peptides and their Multiple Effects at Sub-Inhibitory Concentrations

2020 ◽  
Vol 20 (14) ◽  
pp. 1264-1273 ◽  
Author(s):  
Bruno Casciaro ◽  
Floriana Cappiello ◽  
Walter Verrusio ◽  
Mauro Cacciafesta ◽  
Maria Luisa Mangoni
Keyword(s):  
Antimicrobial Peptides ◽  
Inhibitory Concentration ◽  
Multidrug Resistant ◽  
Mechanisms Of Action ◽  
New Drugs ◽  
Lead Compounds ◽  
Bacterial Pathogenicity ◽  
Growth Inhibitory ◽  
Resistant Strains ◽  
Conventional Antibiotics

The frequent occurrence of multidrug-resistant strains to conventional antimicrobials has led to a clear decline in antibiotic therapies. Therefore, new molecules with different mechanisms of action are extremely necessary. Due to their unique properties, antimicrobial peptides (AMPs) represent a valid alternative to conventional antibiotics and many of them have been characterized for their activity and cytotoxicity. However, the effects that these peptides cause at concentrations below the minimum growth inhibitory concentration (MIC) have yet to be fully analyzed along with the underlying molecular mechanism. In this mini-review, the ability of AMPs to synergize with different antibiotic classes or different natural compounds is examined. Furthermore, data on microbial resistance induction are reported to highlight the importance of antibiotic resistance in the fight against infections. Finally, the effects that sub-MIC levels of AMPs can have on the bacterial pathogenicity are summarized while showing how signaling pathways can be valid therapeutic targets for the treatment of infectious diseases. All these aspects support the high potential of AMPs as lead compounds for the development of new drugs with antibacterial and immunomodulatory activities.

Phenolic Imidazole Derivatives with Dual Antioxidant/Antifungal Activity: Synthesis and Structure-Activity Relationship

2019 ◽  
Vol 15 (4) ◽  
pp. 341-351 ◽  
Author(s):  
Ana P. Bettencourt ◽  
Marián Castro ◽  
João P. Silva ◽  
Francisco Fernandes ◽  
Olga P. Coutinho ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antifungal Activity ◽  
Organic Molecules ◽  
Inhibitory Concentration ◽  
Yeast Species ◽  
Dpph Radical ◽  
Dpph Assay ◽  
Gram Negative ◽  
Structure Activity ◽  
Deoxyribose Degradation

Background: Previous publications show that the addition of a phenolic antioxidant to an antifungal agent, considerably enhances the antifungal activity. Objective: Synthesis of novel compounds combining phenolic units with linear or cyclic nitrogencontaining organic molecules with antioxidant/antifungal activity using methodologies previously developed in the group. Methods: Several N- [1,2-dicyano-2- (arylidenamino) vinyl]-O-alkylformamidoximes 3 were synthesized and cyclized to 4,5-dicyano-N- (N´-alcoxyformimidoyl)-2-arylimidazoles 4 upon reflux in DMF, in the presence of manganese dioxide or to 6-cyano-8-arylpurines 5 when the reagent was refluxed in acetonitrile with an excess of triethylamine. These compounds were tested for their antioxidant activity by cyclic voltammetry, DPPH radical (DPPH•) assay and deoxyribose degradation assay. The minimum inhibitory concentration (MIC) of all compounds was evaluated against two yeast species, Saccharomyces cerevisiae and Candida albicans, and against bacteria Bacillus subtilis (Gram-positive) and Escherichia coli (Gram negative). Their cytotoxicity was evaluated in fibroblasts. Results: Among the synthetised compounds, five presented higher antioxidant activity than reference antioxidant Trolox and from these compounds, four presented antifungal activity without toxic effects in fibroblasts and bacteria. Conclusion: Four novel compounds presented dual antioxidant/antifungal activity at concentrations that are not toxic to bacteria and fibroblasts. The active molecules can be used as an inspiration for further studies in this area.

Sign in / Sign up

Export Citation Format

Share Document