scholarly journals COMBINED ANTIBACTERIAL EFFECT IN VITRO OF HUMAN SALIVARY PROLINE-RICH PEPTIDE P-F (43-61) AND CATIONIC ANTIMICROBIAL PEPTIDES

2018 ◽  
Author(s):  
M.S. Zharkova ◽  
T.O. Makarova ◽  
D.S. Orlov ◽  
P.M. Kopeykin ◽  
S.B. Orlov ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Antibacterial Effect ◽  
Cationic Antimicrobial Peptides ◽  
Proline Rich Peptide

Potent cationic antimicrobial peptides against Mycobacterium tuberculosis in vitro

2019 ◽  
Vol 19 ◽  
pp. 132-135 ◽  
Author(s):  
Sara Silva ◽  
Anabela Santos-Silva ◽  
José Manuel Correia da Costa ◽  
Nuno Vale
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Antimicrobial Peptides ◽  
Cationic Antimicrobial Peptides

scholarly journals In VitroCross-Resistance to Daptomycin and Host Defense Cationic Antimicrobial Peptides in Clinical Methicillin-Resistant Staphylococcus aureus Isolates

2011 ◽  
Vol 55 (9) ◽  
pp. 4012-4018 ◽  
Author(s):  
Nagendra N. Mishra ◽  
James McKinnell ◽  
Michael R. Yeaman ◽  
Aileen Rubio ◽  
Cynthia C. Nast ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Cell Membrane ◽  
Antimicrobial Peptides ◽  
Surface Charge ◽  
Host Defense ◽  
Cationic Antimicrobial Peptides ◽  
Methicillin Resistant ◽  
Membrane Order

ABSTRACTWe investigated the hypothesis that methicillin-resistantStaphylococcus aureus(MRSA) isolates developing reduced susceptibilities to daptomycin (DAP; a calcium-dependent molecule acting as a cationic antimicrobial peptide [CAP]) may also coevolve reducedin vitrosusceptibilities to host defense cationic antimicrobial peptides (HDPs). Ten isogenic pairs of clinical MRSA DAP-susceptible/DAP-resistant (DAPs/DAPr) strains were tested against two distinct HDPs differing in structure, mechanism of action, and origin (thrombin-induced platelet microbicidal proteins [tPMPs] and human neutrophil peptide-1 [hNP-1]) and one bacterium-derived CAP, polymyxin B (PMB). Seven of 10 DAPrstrains had point mutations in themprFlocus (with or withoutyycoperon mutations), while three DAPrstrains had neither mutation. Several phenotypic parameters previously associated with DAPrwere also examined: cell membrane order (fluidity), surface charge, and cell wall thickness profiles. Compared to the 10 DAPsparental strains, their respective DAPrstrains exhibited (i) significantly reduced susceptibility to killing by all three peptides (P< 0.05), (ii) increased cell membrane fluidity, and (iii) significantly thicker cell walls (P< 0.0001). There was no consistent pattern of surface charge profiles distinguishing DAPsand DAPrstrain pairs. Reducedin vitrosusceptibility to two HDPs and one bacterium-derived CAP tracked closely with DAPrin these 10 recent MRSA clinical isolates. These results suggest that adaptive mechanisms involved in the evolution of DAPralso provide MRSA with enhanced survivability against HDPs. Such adaptations appear to correlate with MRSA variations in cell membrane order and cell wall structure. DAPrstrains with or without mutations in themprFlocus demonstrated significant cross-resistance profiles to these unrelated CAPs.

scholarly journals Perturbations of Phosphatidate Cytidylyltransferase (CdsA) Mediate Daptomycin Resistance in Streptococcus mitis/oralis by a Novel Mechanism

2017 ◽  
Vol 61 (4) ◽  
Author(s):  
Nagendra N. Mishra ◽  
Truc T. Tran ◽  
Ravin Seepersaud ◽  
Cristina Garcia-de-la-Maria ◽  
Kym Faull ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Cross Resistance ◽  
Human Neutrophils ◽  
Small Subset ◽  
Streptococcus Mitis ◽  
Anionic Phospholipid ◽  
Cationic Antimicrobial Peptides ◽  
Content Type ◽  
High Level

ABSTRACT Streptococcus mitis/oralis is an important pathogen, causing life-threatening infections such as endocarditis and severe sepsis in immunocompromised patients. The β-lactam antibiotics are the usual therapy of choice for this organism, but their effectiveness is threatened by the frequent emergence of resistance. The lipopeptide daptomycin (DAP) has been suggested for therapy against such resistant S. mitis/oralis strains due to its in vitro bactericidal activity and demonstrated efficacy against other Gram-positive pathogens. Unlike other bacteria, however, S. mitis/oralis has the unique ability to rapidly develop stable, high-level resistance to DAP upon exposure to the drug both in vivo and in vitro. Using isogenic DAP-susceptible and DAP-resistant S. mitis/oralis strain pairs, we describe a mechanism of resistance to both DAP and cationic antimicrobial peptides that involves loss-of-function mutations in cdsA (encoding a phosphatidate cytidylyltransferase). CdsA catalyzes the synthesis of cytidine diphosphate-diacylglycerol, an essential phospholipid intermediate for the production of membrane phosphatidylglycerol and cardiolipin. DAP-resistant S. mitis/oralis strains demonstrated a total disappearance of phosphatidylglycerol, cardiolipin, and anionic phospholipid microdomains from membranes. In addition, these strains exhibited cross-resistance to cationic antimicrobial peptides from human neutrophils (i.e., hNP-1). Interestingly, CdsA-mediated changes in phospholipid metabolism were associated with DAP hyperaccumulation in a small subset of the bacterial population, without any binding by the remaining larger population. Our results indicate that CdsA is the major mediator of high-level DAP resistance in S. mitis/oralis and suggest a novel mechanism of bacterial survival against attack by antimicrobial peptides of both innate and exogenous origins.

Antimicrobial peptides for the treatment of pulmonary tuberculosis, allies or foes?

2018 ◽  
Vol 24 (10) ◽  
pp. 1138-1147
Author(s):  
Bruno Rivas-Santiago ◽  
Flor Torres-Juarez
Keyword(s):  
Pulmonary Tuberculosis ◽  
Antimicrobial Peptides ◽  
Experimental Models ◽  
New Drugs ◽  
World Health ◽  
Public Health Issue ◽  
Health Organization ◽  
Drug Resistant Strains

Tuberculosis is an ancient disease that has become a serious public health issue in recent years, although increasing incidence has been controlled, deaths caused by Mycobacterium tuberculosis have been accentuated due to the emerging of multi-drug resistant strains and the comorbidity with diabetes mellitus and HIV. This situation is threatening the goals of World Health Organization (WHO) to eradicate tuberculosis in 2035. WHO has called for the creation of new drugs as an alternative for the treatment of pulmonary tuberculosis, among the plausible molecules that can be used are the Antimicrobial Peptides (AMPs). These peptides have demonstrated remarkable efficacy to kill mycobacteria in vitro and in vivo in experimental models, nevertheless, these peptides not only have antimicrobial activity but also have a wide variety of functions such as angiogenesis, wound healing, immunomodulation and other well-described roles into the human physiology. Therapeutic strategies for tuberculosis using AMPs must be well thought prior to their clinical use; evaluating comorbidities, family history and risk factors to other diseases, since the wide function of AMPs, they could lead to collateral undesirable effects.

Cationic Antimicrobial Peptides for Tuberculosis: A Mini-Review

2019 ◽  
Vol 20 (9) ◽  
pp. 885-892
Author(s):  
Sara Silva ◽  
Nuno Vale
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Amino Acid ◽  
Antimicrobial Peptides ◽  
Resistance Mechanisms ◽  
Therapeutic Agents ◽  
Pharmacological Properties ◽  
Therapeutic Activity ◽  
Alternative Strategies ◽  
Cationic Antimicrobial Peptides ◽  
Specific Amino Acid

Cationic antimicrobial peptides (CAMPs) can be considered as new potential therapeutic agents for Tuberculosis treatment with a specific amino acid sequence. New studies can be developed in the future to improve the pharmacological properties of CAMPs and also understand possible resistance mechanisms. This review discusses the principal properties of natural and/or synthetic CAMPs, and how these new peptides have a significant specificity for Mycobacterium tuberculosis. Also, we propose some alternative strategies to enhance the therapeutic activity of these CAMPs that include coadministration with nanoparticles and/or classic drugs.

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