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Sasani E, Yadegari MH, Khodavaisy S, Rezaie S, Salehi M, Getso MI. Virulence Factors and Azole-Resistant Mechanism of Candida Tropicalis Isolated from Candidemia. Mycopathologia 2021; 186:847-856. [PMID: 34410566 DOI: 10.1007/s11046-021-00580-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/14/2021] [Indexed: 10/25/2022]
Abstract
BACKGROUND Limited knowledge exists on the virulence factors of Candida tropicalis and the mechanisms of azole resistance that lead to an intensified pathogenicity and treatment failure. We aimed to evaluate the virulence factors and molecular mechanisms of azole resistance among C. tropicalis isolated from patients with candidemia. MATERIALS AND METHODS Several virulence factors, including extracellular enzymatic activities, cell surface hydrophobicity (CSH), and biofilm formation, were evaluated. Antifungal susceptibility pattern and expression level of ERG11, UPC2, MDR1, and CDR1 genes of eight (4 fluconazole resistance and 4 fluconazole susceptible) clinical C. tropicalis isolates were assessed. The correlation between the virulence factors and antifungal susceptibility patterns was analyzed. RESULTS During a 4 year study, forty-five C. tropicalis isolates were recovered from candidemia patients. The isolates expressed different frequencies of virulence determinants as follows: coagulase 4 (8.9%), phospholipase 5 (11.1%), proteinase 31 (68.9%), esterase 43 (95.6%), hemolysin 44 (97.8%), biofilm formation 45 (100%) and CSH 45(100%). All the isolates were susceptible to amphotericin B and showed the highest resistance to voriconazole. There was a significant positive correlation between micafungin minimum inhibitory concentrations (MICs) and hemolysin production (rs = 0.316). However, we found a negative correlation between fluconazole MICs and esterase production (rs = -0.383). We observed the high expression of ERG11 and UPC2 genes in fluconazole-resistant C. tropicalis isolates. CONCLUSION C. tropicalis isolated from candidemia patients extensively displayed capacities for biofilm formation, hemolysis, esterase activity, and hydrophobicity. In addition, the overexpression of ERG11 and UPC2 genes was considered one of the possible mechanisms of azole resistance.
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Affiliation(s)
- Elahe Sasani
- Department of Medical Mycology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Hossein Yadegari
- Department of Medical Mycology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Sadegh Khodavaisy
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
| | - Sassan Rezaie
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammadreza Salehi
- Department of Infectious Diseases and Tropical Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Muhammad Ibrahim Getso
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Department of Medical Microbiology and Parasitology, College of Health Sciences, Bayero University, Kano, Nigeria
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El-Dirany R, Shahrour H, Dirany Z, Abdel-Sater F, Gonzalez-Gaitano G, Brandenburg K, Martinez de Tejada G, Nguewa PA. Activity of Anti-Microbial Peptides (AMPs) against Leishmania and Other Parasites: An Overview. Biomolecules 2021; 11:984. [PMID: 34356608 PMCID: PMC8301979 DOI: 10.3390/biom11070984] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 06/23/2021] [Accepted: 06/26/2021] [Indexed: 12/13/2022] Open
Abstract
Anti-microbial peptides (AMPs), small biologically active molecules, produced by different organisms through their innate immune system, have become a considerable subject of interest in the request of novel therapeutics. Most of these peptides are cationic-amphipathic, exhibiting two main mechanisms of action, direct lysis and by modulating the immunity. The most commonly reported activity of AMPs is their anti-bacterial effects, although other effects, such as anti-fungal, anti-viral, and anti-parasitic, as well as anti-tumor mechanisms of action have also been described. Their anti-parasitic effect against leishmaniasis has been studied. Leishmaniasis is a neglected tropical disease. Currently among parasitic diseases, it is the second most threating illness after malaria. Clinical treatments, mainly antimonial derivatives, are related to drug resistance and some undesirable effects. Therefore, the development of new therapeutic agents has become a priority, and AMPs constitute a promising alternative. In this work, we describe the principal families of AMPs (melittin, cecropin, cathelicidin, defensin, magainin, temporin, dermaseptin, eumenitin, and histatin) exhibiting a potential anti-leishmanial activity, as well as their effectiveness against other microorganisms.
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Affiliation(s)
- Rima El-Dirany
- ISTUN Instituto de Salud Tropical, Department of Microbiology and Parasitology, IdiSNA (Navarra Institute for Health Research), University of Navarra, c/Irunlarrea 1, 31008 Pamplona, Navarra, Spain;
- Faculty of Sciences I, Lebanese University, Hadath 1003, Lebanon; (H.S.); (F.A.-S.)
| | - Hawraa Shahrour
- Faculty of Sciences I, Lebanese University, Hadath 1003, Lebanon; (H.S.); (F.A.-S.)
- Department of Microbiology and Parasitology, IdiSNA (Navarra Institute for Health Research), University of Navarra, 31008 Pamplona, Navarra, Spain;
| | - Zeinab Dirany
- Department of Chemistry, Faculty of Sciences, University of Navarra, 31080 Pamplona, Navarra, Spain; (Z.D.); (G.G.-G.)
| | - Fadi Abdel-Sater
- Faculty of Sciences I, Lebanese University, Hadath 1003, Lebanon; (H.S.); (F.A.-S.)
| | - Gustavo Gonzalez-Gaitano
- Department of Chemistry, Faculty of Sciences, University of Navarra, 31080 Pamplona, Navarra, Spain; (Z.D.); (G.G.-G.)
| | - Klaus Brandenburg
- Brandenburg Antiinfektiva GmbH, c/o Forschungszentrum Borstel, Leibniz Lungenzentrum, 23845 Borstel, Germany;
| | - Guillermo Martinez de Tejada
- Department of Microbiology and Parasitology, IdiSNA (Navarra Institute for Health Research), University of Navarra, 31008 Pamplona, Navarra, Spain;
| | - Paul A. Nguewa
- ISTUN Instituto de Salud Tropical, Department of Microbiology and Parasitology, IdiSNA (Navarra Institute for Health Research), University of Navarra, c/Irunlarrea 1, 31008 Pamplona, Navarra, Spain;
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Lakshmaiah Narayana J, Chen JY. Antimicrobial peptides: Possible anti-infective agents. Peptides 2015; 72:88-94. [PMID: 26048089 DOI: 10.1016/j.peptides.2015.05.012] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 05/10/2015] [Accepted: 05/13/2015] [Indexed: 12/20/2022]
Abstract
Multidrug-resistant bacterial, fungal, viral, and parasitic infections are major health threats. The Infectious Diseases Society of America has expressed concern on the decrease of pharmaceutical companies working on antibiotic research and development. However, small companies, along with academic research institutes, are stepping forward to develop novel therapeutic methods to overcome the present healthcare situation. Among the leading alternatives to current drugs are antimicrobial peptides (AMPs), which are abundantly distributed in nature. AMPs exhibit broad-spectrum activity against a wide variety of bacteria, fungi, viruses, and parasites, and even cancerous cells. They also show potential immunomodulatory properties, and are highly responsive to infectious agents and innate immuno-stimulatory molecules. In recent years, many AMPs have undergone or are undergoing clinical development, and a few are commercially available for topical and other applications. In this review, we outline selected anion and cationic AMPs which are at various stages of development, from preliminary analysis to clinical drug development. Moreover, we also consider current production methods and delivery tools for AMPs, which must be improved for the effective use of these agents.
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Affiliation(s)
- Jayaram Lakshmaiah Narayana
- Doctoral Degree Program in Marine Biotechnology, Institute of Cellular and Orgasmic Biology, Academia Sinica and National Sun-Yat Sen University, Kaohsiung, Taiwan; Marine Research Station, Institute of Cellular and Orgasmic Biology, Academia Sinica, Jiaushi, Ilan, Taiwan
| | - Jyh-Yih Chen
- Marine Research Station, Institute of Cellular and Orgasmic Biology, Academia Sinica, Jiaushi, Ilan, Taiwan.
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Bozoglan O, Mese B, Eroglu E, Elveren S, Gul M, Celik A, Yildirimdemir HI, Ciralik H, Yasim A. Which prosthesis is more resistant to vascular graft infection: polytetrafluoroethylene or Omniflow II biosynthetic grafts? Surg Today 2015; 46:363-70. [DOI: 10.1007/s00595-015-1141-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 02/09/2015] [Indexed: 11/29/2022]
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Xu X, Lai R. The chemistry and biological activities of peptides from amphibian skin secretions. Chem Rev 2015; 115:1760-846. [PMID: 25594509 DOI: 10.1021/cr4006704] [Citation(s) in RCA: 235] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Xueqing Xu
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology , Kunming 650223, Yunnan, China
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Thivierge K, Cotton S, Schaefer DA, Riggs MW, To J, Lund ME, Robinson MW, Dalton JP, Donnelly SM. Cathelicidin-like helminth defence molecules (HDMs): absence of cytotoxic, anti-microbial and anti-protozoan activities imply a specific adaptation to immune modulation. PLoS Negl Trop Dis 2013; 7:e2307. [PMID: 23875042 PMCID: PMC3708846 DOI: 10.1371/journal.pntd.0002307] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 05/29/2013] [Indexed: 11/19/2022] Open
Abstract
Host defence peptides (HDPs) are expressed throughout the animal and plant kingdoms. They have multifunctional roles in the defence against infectious agents of mammals, possessing both bactericidal and immune-modulatory activities. We have identified a novel family of molecules secreted by helminth parasites (helminth defence molecules; HDMs) that exhibit similar structural and biochemical characteristics to the HDPs. Here, we have analyzed the functional activities of four HDMs derived from Schistosoma mansoni and Fasciola hepatica and compared them to human, mouse, bovine and sheep HDPs. Unlike the mammalian HDPs the helminth-derived HDMs show no antimicrobial activity and are non-cytotoxic to mammalian cells (macrophages and red blood cells). However, both the mammalian- and helminth-derived peptides suppress the activation of macrophages by microbial stimuli and alter the response of B cells to cytokine stimulation. Therefore, we hypothesise that HDMs represent a novel family of HDPs that evolved to regulate the immune responses of their mammalian hosts by retaining potent immune modulatory properties without causing deleterious cytotoxic effects. In mammals, secreted host defence peptides (HDPs) protect against a wide range of infectious pathogens. They also perform a range of immune modulatory functions which regulate the immune response to pathogens, ensuring that the protective inflammatory response is not exacerbated and that post-infection repair mechanisms are initiated. We identified a novel family of molecules secreted by medically-important helminth pathogens (termed helminth defence molecules; HDMs) that exhibit striking structural and biochemical similarities to the HDPs. To further investigate the extent of this similarity, we have performed a comparative functional study between several well characterized, anti-microbial, mammalian HDPs and a series of parasite-derived peptides. The parasite HDMs displayed immune modulatory properties that were similar to their HDP homologs in mammals, but possessed no antimicrobial or cytotoxic activity. We propose that HDMs of these helminth pathogens underwent specific adaptation, losing their anti-microbial activity but retaining their ability to regulate the immune responses of their mammalian hosts. This absence of cytotoxicity and retention of immune-modulatory activity offers an opportunity to design novel immunotherapeutics derived from the HDMs which could be used to combat destructive inflammatory responses associated with microbial infection and immune-related disorders.
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Affiliation(s)
- Karine Thivierge
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
- Laboratoire de Santé Publique du Québec, Institut National de Santé Publique du Québec, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Sophie Cotton
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Deborah A. Schaefer
- Department of Veterinary Science and Microbiology, University of Arizona, Tucson, Arizona, United States of America
| | - Michael W. Riggs
- Department of Veterinary Science and Microbiology, University of Arizona, Tucson, Arizona, United States of America
| | - Joyce To
- The ithree Institute, University of Technology Sydney (UTS), Sydney, Australia
| | - Maria E. Lund
- The ithree Institute, University of Technology Sydney (UTS), Sydney, Australia
| | - Mark W. Robinson
- The ithree Institute, University of Technology Sydney (UTS), Sydney, Australia
- School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, Belfast, Northern Ireland
| | - John P. Dalton
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Sheila M. Donnelly
- The ithree Institute, University of Technology Sydney (UTS), Sydney, Australia
- * E-mail:
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Naumenkova TV, Antonov MY, Nikolaev IN, Shaitan KV. Effect of Pro11Ala substitution on the structural and functional properties of antimicrobial peptide buforin 2. Biophysics (Nagoya-shi) 2012. [DOI: 10.1134/s0006350912060127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Carryn S, Schaefer DA, Imboden M, Homan EJ, Bremel RD, Riggs MW. Phospholipases and cationic peptides inhibit Cryptosporidium parvum sporozoite infectivity by parasiticidal and non-parasiticidal mechanisms. J Parasitol 2011; 98:199-204. [PMID: 21787211 DOI: 10.1645/ge-2822.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The apicomplexan parasite Cryptosporidium parvum is an important cause of diarrhea in humans and cattle, and it can persistently infect immunocompromised hosts. No consistently effective parasite-specific pharmaceuticals or immunotherapies for control of cryptosporidiosis are presently available. The innate immune system represents the first line of host defense against a range of infectious agents, including parasitic protozoa. Several types of antimicrobial peptides and proteins, collectively referred to herein as biocides, constitute a major effector component of this system. In the present study, we evaluated lactoferrin, lactoferrin hydrolysate, 5 cationic peptides (lactoferricin B, cathelicidin LL37, indolicidin, β-defensin 1, β-defensin 2), lysozyme, and 2 phospholipases (phospholipase A2, and phosphatidylinositol-specific phospholipase C) for anti-cryptosporidial activity. The biocides were evaluated either alone or in combination with 3E2, a monoclonal antibody (MAb) against C. parvum that inhibits sporozoite attachment and invasion. Sporozoite viability and infectivity were used as indices of anti-cryptosporidial activity in vitro. All biocides except lactoferrin had a significant effect on sporozoite viability and infectivity. Lactoferrin hydrolysate and each of the 5 cationic peptides were highly parasiticidal and strongly reduced sporozoite infectivity. While each phospholipase also had parasiticidal activity, it was significantly less than that of lactoferrin hydrolysate and each of the cationic peptides. However, each phospholipase reduced sporozoite infectivity comparably to that observed with lactoferrin hydrolysate and the cationic peptides. Moreover, when 3 of the cationic peptides (cathelicidin LL37, β-defensin 1, and β-defensin 2) were individually combined with MAb 3E2, a significantly greater reduction of sporozoite infectivity was observed over that by 3E2 alone. In contrast, reduction of sporozoite infectivity by a combination of either phospholipase with MAb 3E2 was no greater than that by 3E2 alone. These collective observations suggest that cationic peptides and phospholipases neutralize C. parvum by mechanisms that are predominantly either parasiticidal or non-parasiticidal, respectively.
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Affiliation(s)
- Stéphane Carryn
- Department of Veterinary Science and Microbiology, University of Arizona, Tucson, Arizona 85721, USA
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Abstract
Whereas significant knowledge is accumulating on the antibacterial and antifungal properties of host defense peptides (HDPs) and their synthetic mimics, much less is known of their activities against parasites. A variety of in vitro and in vivo antiparasitic assays suggest that these notorious antimicrobial compounds could represent a powerful tool for the development of novel drugs to fight parasites in the vertebrate host or to complement current therapeutic strategies, albeit the fact that HDPs essentially act by nonspecific mechanisms casts serious doubt on their ability to exert sufficient selectivity to be considered ideal candidates for drug development. This minireview summarizes recent efforts to assess the antiparasitic properties of HDPs and their synthetic derivatives, focusing on two of the most used models - Plasmodium and Leishmania species - for antiparasitic assays against the different development stages.
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Affiliation(s)
- Amram Mor
- Department of Biotechnology & Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel.
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Rivas L, Luque-Ortega JR, Andreu D. Amphibian antimicrobial peptides and Protozoa: Lessons from parasites. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:1570-81. [DOI: 10.1016/j.bbamem.2008.11.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 10/29/2008] [Accepted: 11/03/2008] [Indexed: 02/06/2023]
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Atahan E. Vascular graft infection by Staphylococcus aureus: efficacy of linezolid, teicoplanin and vancomycin systemic prophylaxis protocols in a rat model. Cardiovasc J Afr 2009; 20:122-5. [PMID: 19421648 PMCID: PMC3721769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE We investigated experimentally the in vivo prophylactic efficacies of linezolid, teicoplanin and vancomycin in subcutaneously implanted dacron graft infection caused by methicillin-resistant Staphylococcus aureus (MRSA). MATERIALS AND METHODS Dacron grafts (1 cm(2)) were aseptically implanted into subcutaneous pockets that were surgically prepared in the backs of 50 rats. Ten of these rats were used as the control group (group I). Grafts in the remaining 40 rats were infected by inoculation of MRSA at the concentration of 2 x 10(7) colony-forming units (CFU)/ml. Ten of these rats constituted the contaminated, untreated group II. The other three study groups comprising 10 rats each were contaminated and then treated with linezolid (group III), teicoplanin (group IV) and vancomycin (group V), respectively. All rats were sacrificed and the grafts were removed after seven days and evaluated. RESULTS The bacterial count decreased in the rats from the groups treated with linezolid, teicoplanin and vancomycin. The linezolid and teicoplanin groups, however, showed a significantly lower bacterial number than the vancomycin group (p = 0.009 and p = 0.01). The intensity of inflammation was highest in the contaminated, untreated group, as expected. CONCLUSIONS Single-dose linezolid, teicoplanin and vancomycin for peri-operative prophylaxis may prevent bacterial growth in vascular graft infections. The effect of linezolid and teicoplanin seemed similar and their effect was greater than that of vancomycin.
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Affiliation(s)
- Erhan Atahan
- Department of Cardiovascular Surgery, Cumhuriyet University School of Medicine, Sivas, Turkey
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Cho JH, Sung BH, Kim SC. Buforins: histone H2A-derived antimicrobial peptides from toad stomach. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:1564-9. [PMID: 19041293 DOI: 10.1016/j.bbamem.2008.10.025] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 10/27/2008] [Accepted: 10/31/2008] [Indexed: 10/21/2022]
Abstract
Antimicrobial peptides (AMPs) constitute an important component of the innate immune system in a variety of organisms. Buforin I is a 39-amino acid AMP that was first isolated from the stomach tissue of the Asian toad Bufo bufo gargarizans. Buforin II is a 21-amino acid peptide that is derived from buforin I and displays an even more potent antimicrobial activity than its parent AMP. Both peptides share complete sequence identity with the N-terminal region of histone H2A that interacts directly with nucleic acids. Buforin I is generated from histone H2A by pepsin-directed proteolysis in the cytoplasm of gastric gland cells. After secretion into the gastric lumen, buforin I remains adhered to the mucous biofilm that lines the stomach, thus providing a protective antimicrobial coat. Buforins, which house a helix-hinge-helix domain, kill a microorganism by entering the cell without membrane permeabilization and thus binding to nucleic acids. The proline hinge is crucial for the cell penetrating activity of buforins. Buforins also are known to possess anti-endotoxin and anticancer activities, thus making these peptides attractive reagents for pharmaceutical applications. This review describes the role of buforins in innate host defense; future research paradigms; and use of these agents as human therapeutics.
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Affiliation(s)
- Ju Hyun Cho
- Department of Biology, Research Institute of Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea
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Zintl A, Mulcahy G, de Waal T, de Waele V, Byrne C, Clyne M, Holden N, Fanning S. An Irish perspective on Cryptosporidium. Part 2. Ir Vet J 2006; 59:495-500. [PMID: 21851686 PMCID: PMC3113897 DOI: 10.1186/2046-0481-59-9-495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cryptosporidiosis, a protozoal disease which causes significant morbidity in humans, is one of the chief causes of diarrhoea in neonatal ruminants. although the parasite poses a significant threat to public health and animal health in Ireland, its epidemiology on the island is only poorly understood. Environmental studies have shown the waterborne parasite to be widespread in some untreated waterbodies around Ireland. The island's hydrogeological situation, combined with high stocking rates of livestock and the absence of filtration from regular water treatment, render it vulnerable to large-scale outbreaks. This review discusses the parasite in the Irish context and underlines the need for a reference facility to provide active surveillance on the island.
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Affiliation(s)
- Annetta Zintl
- UCD School of Agriculture, Food Science and Veterinary Medicine and Conway Institute of Biomedical and Biomolecular Research, University College Dublin, Ireland
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Guerrero E, Saugar JM, Matsuzaki K, Rivas L. Role of positional hydrophobicity in the leishmanicidal activity of magainin 2. Antimicrob Agents Chemother 2004; 48:2980-6. [PMID: 15273109 PMCID: PMC478506 DOI: 10.1128/aac.48.8.2980-2986.2004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The emergence of membrane-active antimicrobial peptides as new alternatives against pathogens with multiantibiotic resistance requires the design of better analogues. Among the different physicochemical parameters involved in the optimization of linear antimicrobial peptides, positional hydrophobicity has recently been incorporated. This takes into consideration the concept of the topological distribution of hydrophobic residues throughout the sequence rather than the classical concept of hydrophobicity as a global parameter of the peptide, calculated as the summation of the individual hydrophobicities of the residues. In order to assess the contribution of this parameter to the leishmanicidal mechanisms of magainin 2 analogues, the activities of two of these analogues, MG-H1 (GIKKFLHIIWKFIKAFVGEIMNS) and MG-H2 (IIKKFLHSIWKFGKAFVGEIMNI), which have similar charges, amino acid compositions, and hydrophobicities but different positional hydrophobicities, against Leishmania donovani promastigotes were assayed (T. Tachi, R. F. Epand, R. M. Epand, and K. Matsuzaki, Biochemistry 41:10723-10731, 2002). The activities were compared with that of the parental peptide, F5W-magainin 2 (GIGKWLHSAKKFGKAFVGEIMNS). The three peptides were active at micromolar concentrations, in the order MG-H2 > MG-H1 > F5W-magainin 2. These activities differ from their hemolytic and bactericidal activities. The results demonstrate that positional hydrophobicity, which reflects the presence of short stretches of sequences rich in hydrophobic amino acids, plays an important role in the activities of leishmanicidal peptides.
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Affiliation(s)
- Esther Guerrero
- Centro de Investigaciones Biológicas (CSIC), E-28040, Madrid, Spain
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