Studies on the Antibacterial Activity and Mechanism of Antimicrobial Peptides Against Drug-Resistant Bacteria

The quorum sensing (QS) system in multi-drug-resistant bacteria such as P. aeruginosa is primarily responsible for the development of antibiotic resistance and is considered an attractive target for antimicrobial drug discovery. In this study, we synthesised a series of novel selenourea and thiourea-containing dihydropyrrol-2-one (DHP) analogues as LasR antagonists. The selenium DHP derivatives displayed significantly better quorum-sensing inhibition (QSI) activities than the corresponding sulphur analogues. The most potent analogue 3e efficiently inhibited the las QS system by 81% at 125 µM and 53% at 31 µM. Additionally, all the compounds were screened for their minimum inhibitory concentration (MIC) against the Gram-positive bacterium S. aureus, and interestingly, only the selenium analogues showed antibacterial activity, with 3c and 3e being the most potent with a MIC of 15.6 µM.

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Synergistic Antibacterial Activity of Lantana camara L., Parthenium hysterophorus L., Cannabis sativa L. and Justicia adhatoda L. Leaves Extract against Procured Multi-drug Resistant Bacteria In Vitro

European Journal of Medicinal Plants ◽

10.9734/ejmp/2021/v32i330379 ◽

2021 ◽

pp. 34-40

Author(s):

Jyoti Chandola ◽

Pooja Singh ◽

Rishabh Garg ◽

Narotam Sharma

Keyword(s):

Antibacterial Activity ◽

Medicinal Plants ◽

Cannabis Sativa ◽

Lantana Camara ◽

Parthenium Hysterophorus ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria ◽

Weed Plants ◽

Justicia Adhatoda

The scientific study of this research has been focused on synergistic antibacterial activity of two weed plants, Lantana camara L., Parthenium hysterophorus L. alongwith two medicinal plants, Cannabis sativa L., Justicia adhatoda L. against multi- drug resistant (MDR) bacteria. Dried leaf powders of the plants were extracted using air-dried method followed by the ethanol- solvent extraction method for the crude extract of the leaves. The crude extracts were tested for antibacterial activity against three MDR bacteria, that is, one Gram positive bacteria- Staphylococcus aureus and two Gram negative bacteria- Escherichia coli and Proteus mirabilis. Out of 18 antibiotics tested against procured bacteria, Staphylococcus aureus was resistant to 10 out of 10 tested antibiotics, Escherichia coli was resistant to 4 out of 12 tested antibiotics and Proteus mirabilis was resistant to 9 out of 10 tested antibiotics. The tested weed plants and the medicinal plants when combined together showed more zone of inhibition against multidrug resistant bacteria ( Two combinations of phytochemicals Lantana camara, Cannabis sativa and Lantana camara, Cannabis sativa, Justicia adhatoda, Parthenium hysterophorus showed maximum zones of inhibition, that is, 30 mm) as compared to when these plants were tested solitarily, showing pronounced antibacterial activity. These findings showed that the antibacterial activity enhanced when they were combined together and this potential could be used against various infectious diseases with more research and modification in this area. Weed plants also holds as much importance as the medicinal plants although not to that extent, but they clearly inhibit the growth of bacteria and this property of weeds along with the medicinal plants holds a promising future in treating many diseases caused by multi-drug resistant bacteria on the pharmaceutical level.

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Quorum Sensing Inhibition in Chromobacterium violaceum, Antibacterial Activity and GC-MS Analysis of Centaurea praecox (Oliv. & Hiern) Extracts

Letters in Applied NanoBioScience ◽

10.33263/lianbs94.15691577 ◽

2020 ◽

Vol 9 (4) ◽

pp. 1569-1577

Keyword(s):

Antibacterial Activity ◽

Quorum Sensing ◽

Research Strategy ◽

Chromobacterium Violaceum ◽

Resistant Bacteria ◽

Drug Resistant ◽

Control Drug ◽

Ms Analysis ◽

Drug Resistant Bacteria

The quorum sensing (QS) mechanism has become a viable research strategy for the discovery of plant-derived anti-virulent agents to control drug-resistant bacteria. The increasing incidences of drug-resistant bacteria and the effort to curb it necessitate this study. We investigated the QS inhibitory potential of Centaurea praecox extracts on Chromobacterium violaceum (CV), antibacterial activity, and determination of chemical composition using GC-MS. C. praecox was subjected to sequential extraction using hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), ethanol (ET), and aqueous (AQ) solvents. The extracts were subsequently evaluated for antibacterial activity using disc diffusion and QS violacein inhibition using spectrophotometry. The antibacterial effects of the extracts were moderate on gram-positive bacteria at 4 mg/mL in the order: HEX >EA >DCM >ET =AQ. However, the DCM extract demonstrated the most effective violacein inhibition of ≥80% at 0.3 mg/mL. QS violacein inhibitions were generally found to be concentration-dependent in the order: DCM >EA >HEX >ET =AQ with efficacies of ≥ 90% inhibition at ≥ 0.6 mg/mL. GC-MS analysis on the most potent DCM extract revealed N-vinylmethanimine, N-ethyl formamide, and propanamide among components identified. We concluded that C. praecox DCM extract contains bioactive chemicals as QS inhibitors and potential anti-virulent agents capable of combating the pathogenicity of drug-resistant bacteria in vivo.

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Nanoparticles Enable Efficient Delivery of Antimicrobial Peptides for the Treatment of Deep Infections

BIO Integration ◽

10.15212/bioi-2021-0003 ◽

2021 ◽

Author(s):

Yingxue Deng ◽

Rui Huang ◽

Songyin Huang ◽

Menghua Xiong

Keyword(s):

Antimicrobial Peptides ◽

Broad Spectrum ◽

Antimicrobial Properties ◽

Therapeutic Index ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria ◽

Efficient Delivery ◽

Delivery Vehicles

Antimicrobial peptides (AMPs) have emerged as promising alternatives of traditional antibiotics against drug-resistant bacteria owing to their broad-spectrum antimicrobial properties and low tendency to drugresistance. However, their therapeutic efficacy in vivo, especially for infections in deep organs, is limited owing to their systemic toxicity and low bioavailability. Nanoparticles-based delivery systems offer a strategy to increase the therapeutic index of AMPs by preventing proteolysis, increasing the accumulation at infection sites, and reducing toxicity. Herein, we will discuss the current progress of using nanoparticles as delivery vehicles for AMPs for the treatment of deep infections.

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Vacancy‐Induced Antibacterial Activity of XS 2– y Quantum Dots against Drug‐Resistant Bacteria for Treatment of Bacterial Keratitis

Small ◽

10.1002/smll.202004677 ◽

2020 ◽

Vol 16 (42) ◽

pp. 2004677

Author(s):

Huiyuan Li ◽

Xiao Wang ◽

Xiaofei Zhao ◽

Guanhua Li ◽

Fengyan Pei ◽

...

Keyword(s):

Quantum Dots ◽

Antibacterial Activity ◽

Resistant Bacteria ◽

Bacterial Keratitis ◽

Drug Resistant ◽

Drug Resistant Bacteria

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Design, Engineering and Discovery of Novel α-Helical and β-Boomerang Antimicrobial Peptides against Drug Resistant Bacteria

International Journal of Molecular Sciences ◽

10.3390/ijms21165773 ◽

2020 ◽

Vol 21 (16) ◽

pp. 5773 ◽

Cited By ~ 7

Author(s):

Surajit Bhattacharjya ◽

Suzana K. Straus

Keyword(s):

Antimicrobial Peptides ◽

Resistant Bacteria ◽

Drug Resistant ◽

Antibiotic Development ◽

Extensively Drug Resistant ◽

Drug Resistant Bacteria ◽

Drying Up ◽

Further Development ◽

Lps Binding

In an era where the pipeline of new antibiotic development is drying up, the continuous rise of multi-drug resistant (MDR) and extensively drug resistant (XDR) bacteria are genuine threats to human health. Although antimicrobial peptides (AMPs) may serve as promising leads against drug resistant bacteria, only a few AMPs are in advanced clinical trials. The limitations of AMPs, namely their low in vivo activity, toxicity, and poor bioavailability, need to be addressed. Here, we review engineering of frog derived short α-helical AMPs (aurein, temporins) and lipopolysaccharide (LPS) binding designed β-boomerang AMPs for further development. The discovery of novel cell selective AMPs from the human proprotein convertase furin is also discussed.

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LAMP2: a major update of the database linking antimicrobial peptides

Database ◽

10.1093/database/baaa061 ◽

2020 ◽

Vol 2020 ◽

Cited By ~ 2

Author(s):

Guizi Ye ◽

Hongyu Wu ◽

Jinjiang Huang ◽

Wei Wang ◽

Kuikui Ge ◽

...

Keyword(s):

Antimicrobial Peptides ◽

Primary Structure ◽

Scientific Community ◽

Resistant Bacteria ◽

Drug Resistant ◽

Current Version ◽

Functional Activities ◽

Drug Resistant Bacteria ◽

Functional Classes ◽

And Function

Abstract Antimicrobial peptides (AMPs) have been regarded as a potential weapon to fight against drug-resistant bacteria, which is threating the globe. Thus, more and more AMPs had been designed or identified. There is a need to integrate them into a platform for researchers to facilitate investigation and analyze existing AMPs. The AMP database has become an important tool for the discovery and transformation of AMPs as agents. A database linking antimicrobial peptides (LAMPs), launched in 2013, serves as a comprehensive tool to supply exhaustive information of AMP on a single platform. LAMP2, an updated version of LAMP, holds 23 253 unique AMP sequences and expands to link 16 public AMP databases. In the current version, there are more than 50% (12 236) sequences only linking a single database and more than 45% of AMPs linking two or more database links. Additionally, updated categories based on primary structure, collection, composition, source and function have been integrated into LAMP2. Peptides in LAMP2 have been integrated in 8 major functional classes and 38 functional activities. More than 89% (20 909) of the peptides are experimentally validated peptides. A total of 1924 references were extracted and regarded as the evidence for supporting AMP activity and cytotoxicity. The updated version will be helpful to the scientific community.

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Chemical modifications of short antimicrobial peptides from insects and vertebrates to fight multi-drug resistant bacteria

Advances in Experimental Medicine and Biology - Peptides for Youth ◽

10.1007/978-0-387-73657-0_172 ◽

2009 ◽

pp. 395-396 ◽

Cited By ~ 6

Author(s):

Daniel Knappe ◽

Christin Stegemann ◽

Ariane Nimptsch ◽

Alexander Jr Kolobov ◽

Ekaterina Korableva ◽

...

Keyword(s):

Antimicrobial Peptides ◽

Resistant Bacteria ◽

Drug Resistant ◽

Chemical Modifications ◽

Drug Resistant Bacteria

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Recombinant HNP-1 Produced by Escherichia coli Triggers Bacterial Apoptosis and Exhibits Antibacterial Activity against Drug-Resistant Bacteria

Microbiology Spectrum ◽

10.1128/spectrum.00860-21 ◽

2022 ◽

Author(s):

Qi Xie ◽

Yin Wang ◽

Mengmeng Zhang ◽

Shujia Wu ◽

Wei Wei ◽

...

Keyword(s):

Escherichia Coli ◽

Antibacterial Activity ◽

Mass Production ◽

Recombinant Protein Expression ◽

Cost Effective ◽

Resistant Bacteria ◽

Drug Resistant ◽

Effective Solution ◽

Drug Resistant Bacteria ◽

Human Neutrophil Peptide

Human neutrophil peptide-1 (HNP-1) is a promising antibiotic candidate, but its clinical application has been hampered by the difficulty of mass production and an inadequate understanding of its bactericidal mechanisms. In this study, we demonstrated that recombinant protein expression combined with ultrafiltration may be a simple and cost-effective solution to HNP-1 production.

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