Lysine Stapling Screening Provides Stable and Low Toxic Cationic Antimicrobial Peptides Combating Multidrug-Resistant Bacteria In Vitro and In Vivo

The increasing rate of antibiotic resistance constitutes a global health crisis. Antimicrobial peptides (AMPs) have the property to selectively kill bacteria regardless of resistance to traditional antibiotics. However, several challenges (e.g., reduced activity in the presence of serum and lack of efficacy in vivo) to clinical development need to be overcome. In the last two decades, we have addressed many of those challenges by engineering cationic AMPs de novo for optimization under test conditions that typically inhibit the activities of natural AMPs, including systemic efficacy. We reviewed some of the most promising data of the last two decades in the context of the advancement of the field of helical AMPs toward clinical development.

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AMPing up the search: An in silico approach to identifying Antimicrobial Peptides (AMPs) with potential anti-biofilm activity

10.1101/2021.08.16.456477 ◽

2021 ◽

Author(s):

Shreeya Mhade ◽

Stutee Panse ◽

Gandhar Tendulkar ◽

Rohit Awate ◽

Snehal Kadam ◽

...

Keyword(s):

Antimicrobial Peptides ◽

In Silico ◽

Biofilm Formation ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

C Protein ◽

Pilus Biogenesis ◽

Natural And Synthetic

AbstractAntibiotic resistance is a public health threat, and the rise of multidrug-resistant bacteria, including those that form protective biofilms, further compounds this challenge. Antimicrobial peptides (AMPs) have been recognized for their anti-infective properties, including their ability to target processes important for biofilm formation. However, given the vast array of natural and synthetic AMPs, determining potential candidates for anti-biofilm testing is a significant challenge. In this study, we present an in silico approach, based on open-source tools, to identify AMPs with potential anti-biofilm activity. This approach is developed using the sortase-pilin machinery, important for adhesion and biofilm formation, of the multidrug-resistant, biofilm-forming pathogen C. striatum as the target. Using homology modeling, we modeled the structure of the C. striatum sortase C protein, resembling the semi-open lid conformation adopted during pilus biogenesis. Next, we developed a structural library of 5544 natural and synthetic AMPs from sequences in the DRAMP database. From this library, AMPs with known anti-Gram positive activity were filtered, and 100 select AMPs were evaluated for their ability to interact with the sortase C protein using in-silico molecular docking. Based on interacting residues and docking scores, we built a preference scale to categorize candidate AMPs in order of priority for future in vitro and in vivo biofilm studies. The considerations and challenges of our approach, and the resources developed, which includes a search-enabled repository of predicted AMP structures and protein-peptide interaction models relevant to biofilm studies (B-AMP), can be leveraged for similar investigations across other biofilm targets and biofilm-forming pathogens.

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Inhibition of Multidrug-Resistant Gram-Positive and Gram-Negative Bacteria by a Photoactivated Porphyrin

Polish Journal of Microbiology ◽

10.5604/01.3001.0010.7092 ◽

2017 ◽

Vol 66 (4) ◽

pp. 533-536 ◽

Cited By ~ 2

Author(s):

Moreno Bondi ◽

Anna Mazzini ◽

Simona de Niederhäusern ◽

Ramona Iseppi ◽

Patrizia Messi

Keyword(s):

Multidrug Resistant ◽

Resistant Bacteria ◽

Gram Negative Bacteria ◽

Multidrug Resistant Bacteria ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

In Vitro Antibacterial Activity

The authors studied the in vitro antibacterial activity of the photo-activated porphyrin meso-tri(N-methyl-pyridyl), mono(N-tetradecyl-pyridyl)porphine (C14) against four multidrug-resistant bacteria: Staphylococcus aureus, Enterococcus faecalis (Gram-positive), Escherichia coli, Pseudomonas aeruginosa (Gram-negative). Using 10 μg/ml of porphyrin and 60 sec irradiation we observed the remarkable susceptibility of S. aureus and E. faecalis to treatment while, under the same conditions, E. coli and P. aeruginosa showed very low susceptibility. In a later stage, suspensions of Gram-negative bacteria were processed with EDTA before photo-activation, obtaining a significant decrease in viable counts. In view of the results, if the combination of low porphyrin concentrations and short irradiation times will be effective in vivo also, this approach could be a possible alternative to antibiotics, in particular against localized infections due to multidrug-resistant microorganisms.

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Amphipathic Dendritic Poly-peptides Carrier to Deliver Antisense Oligonucleotides Against Multi-drug Resistant Bacteria in Vitro and in Vivo

10.21203/rs.3.rs-1020707/v1 ◽

2021 ◽

Author(s):

Zhou Chen ◽

Yue Hu ◽

Xinggang Mao ◽

Dan Nie ◽

Hui Zhao ◽

...

Keyword(s):

Antisense Oligonucleotides ◽

Multidrug Resistant ◽

Great Promise ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

Histidine Residues ◽

Novel Approach ◽

Global Health Issue

Abstract Background: Outbreaks of infection due to multidrug-resistant bacteria, especially gram-negative bacteria, have become a global health issue in both hospitals and communities. Antisense oligonucleotides (ASOs) based therapeutics hold a great promise for treating infections caused by multidrug-resistant bacteria. However, ASOs therapeutics are strangled because of its low cell penetration efficiency caused by the high molecular weight and hydrophilicity.Results: Here, we designed a series of dendritic poly-peptides (DPP1 to DPP12) to encapsulate ASOs to form DSPE-mPEG2000 decorated ASOs/DPP nanoparticles (DP-AD1 to DP-AD12) and observed that amphipathic DP-AD2, 3, 7 or 8 with a positive charge ≥ 8 showed great efficiency to deliver ASOs into bacteria, but only the two histidine residues contained DP-AD7 and DP-AD8 significantly inhibited the bacterial growth and the targeted gene expression of tested bacteria in vitro. DP-AD7anti-acpP remarkably increased the survival rate of septic mice infected by ESBLs-E. coli, exhibiting strong antibacterial effects in vivo.Conclusions: For the first time, we designed DPP as a potent carrier to deliver ASOs for combating MDR bacteria and demonstrated essential features, namely, amphipathicity, 8–10 positive charges, and 2 histidine residues, that are required for efficient DPP based delivery, and provide a novel approach for the development and research of the antisense antibacterial strategy.

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Antimicrobial Photodynamic Therapy for Methicillin-ResistantStaphylococcus aureusInfection

BioMed Research International ◽

10.1155/2013/159157 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 35

Author(s):

Xiu-jun Fu ◽

Yong Fang ◽

Min Yao

Keyword(s):

Photodynamic Therapy ◽

Multidrug Resistant ◽

In Vivo Studies ◽

Resistant Bacteria ◽

Antimicrobial Photodynamic Therapy ◽

Multidrug Resistant Bacteria ◽

Resistant Infection ◽

Mrsa Infection

Nowadays methicillin-resistantStaphylococcus aureus(MRSA) is one of the most common multidrug resistant bacteria both in hospitals and in the community. In the last two decades, there has been growing concern about the increasing resistance to MRSA of the most potent antibiotic glycopeptides. MRSA infection poses a serious problem for physicians and their patients. Photosensitizer-mediated antimicrobial photodynamic therapy (PDT) appears to be a promising and innovative approach for treating multidrug resistant infection. In spite of encouraging reports of the use of antimicrobial PDT to inactivate MRSA in large in vitro studies, there are only few in vivo studies. Therefore, applying PDT in the clinic for MRSA infection is still a long way off.

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Effects of Probiotics in the Management of Infected Chronic Wounds: From Cell Culture to Human Studies

Current Clinical Pharmacology ◽

10.2174/1574884714666191111130630 ◽

2020 ◽

Vol 15 (3) ◽

pp. 193-206

Author(s):

Brognara Lorenzo ◽

Salmaso Luca ◽

Mazzotti Antonio ◽

Di M. Alberto ◽

Faldini Cesare ◽

...

Keyword(s):

Chronic Wounds ◽

Animal Experiments ◽

Multidrug Resistant ◽

Preliminary Evidence ◽

Human Studies ◽

In Vivo Studies ◽

Resistant Bacteria ◽

Keywords Probiotics

Background: Chronic wounds are commonly associated with polymicrobial biofilm infections. In the last years, the extensive use of antibiotics has generated several antibiotic-resistant variants. To overcome this issue, alternative natural treatments have been proposed, including the use of microorganisms like probiotics. The aim of this manuscript was to review current literature concerning the application of probiotics for the treatment of infected chronic wounds. Methods: Relevant articles were searched in the Medline database using PubMed and Scholar, using the keywords “probiotics” and “wound” and “injuries”, “probiotics” and “wound” and “ulcer”, “biofilm” and “probiotics” and “wound”, “biofilm” and “ulcer” and “probiotics”, “biofilm” and “ulcer” and “probiotics”, “probiotics” and “wound”. Results: The research initially included 253 articles. After removal of duplicate studies, and selection according to specific inclusion and exclusion criteria, 19 research articles were included and reviewed, accounting for 12 in vitro, 8 in vivo studies and 2 human studies (three articles dealing with animal experiments included also in vitro testing). Most of the published studies about the effects of probiotics for the treatment of infected chronic wounds reported a partial inhibition of microbial growth, biofilm formation and quorum sensing. Discussion: The application of probiotics represents an intriguing option in the treatment of infected chronic wounds with multidrug-resistant bacteria; however, current results are difficult to compare due to the heterogeneity in methodology, laboratory techniques, and applied clinical protocols. Lactobacillus plantarum currently represents the most studied strain, showing a positive application in burns compared to guideline treatments, and an additional mean in chronic wound infections. Conclusions: Although preliminary evidence supports the use of specific strains of probiotics in certain clinical settings such as infected chronic wounds, large, long-term clinical trials are still lacking, and further research is needed.

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In vitro activity of antimicrobial peptide CDP-B11 alone and in combination with colistin against colistin-resistant and multidrug-resistant Escherichia coli

Scientific Reports ◽

10.1038/s41598-021-81140-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kaitlin S. Witherell ◽

Jason Price ◽

Ashok D. Bandaranayake ◽

James Olson ◽

Douglas R. Call

Keyword(s):

Escherichia Coli ◽

Antimicrobial Peptide ◽

Membrane Integrity ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

E Coli ◽

Minimal Media

AbstractMultidrug-resistant bacteria are a growing global concern, and with increasingly prevalent resistance to last line antibiotics such as colistin, it is imperative that alternative treatment options are identified. Herein we investigated the mechanism of action of a novel antimicrobial peptide (CDP-B11) and its effectiveness against multidrug-resistant bacteria including Escherichia coli #0346, which harbors multiple antibiotic-resistance genes, including mobilized colistin resistance gene (mcr-1). Bacterial membrane potential and membrane integrity assays, measured by flow cytometry, were used to test membrane disruption. Bacterial growth inhibition assays and time to kill assays measured the effectiveness of CDP-B11 alone and in combination with colistin against E. coli #0346 and other bacteria. Hemolysis assays were used to quantify the hemolytic effects of CDP-B11 alone and in combination with colistin. Findings show CDP-B11 disrupts the outer membrane of E. coli #0346. CDP-B11 with colistin inhibits the growth of E. coli #0346 at ≥ 10× lower colistin concentrations compared to colistin alone in Mueller–Hinton media and M9 media. Growth is significantly inhibited in other clinically relevant strains, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In rich media and minimal media, the drug combination kills bacteria at a lower colistin concentration (1.25 μg/mL) compared to colistin alone (2.5 μg/mL). In minimal media, the combination is bactericidal with killing accelerated by up to 2 h compared to colistin alone. Importantly, no significant red blood hemolysis is evident for CDP-B11 alone or in combination with colistin. The characteristics of CDP-B11 presented here indicate that it can be used as a potential monotherapy or as combination therapy with colistin for the treatment of multidrug-resistant infections, including colistin-resistant infections.

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