Дисертації з теми "Antimicrobial PEPTIDES IN VIVO"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Antimicrobial PEPTIDES IN VIVO".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Waldbrook, Matthew George. "In vivo efficacy of novel antibacterial and immunomodulatory peptides." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2850.
Повний текст джерелаPelillo, Chiara. "Therapeutic potential of BAC7(I-35), a Proline-rich Antimicrobial Peptide: in vitro and in vivo studies and Pegylation strategy to improve its bioavailability." Doctoral thesis, Università degli studi di Trieste, 2011. http://hdl.handle.net/10077/5978.
Повний текст джерелаThe antimicrobial peptides (AMPs) are an important component of the innate defense against invading microorganisms, are widespread in nature and may have multiple and diversified mechanisms of bactericidal action. In addition to their direct antimicrobial activity the are also involved in other biological processes. The aim of this project was to investigate the in vivo activity of Bac7(1-35), a bovine proline-rich antimicrobial peptide, having in mind its possible use as a lead compound for the development of novel anti-infective agents. Before moving to animal models of infection, the in vitro stability of the peptide in the presence of murine and human serum or plasma as well as its biodistribution in mouse were investigated. Antibacterial activity assays against Salmonella enterica showed that the presence of murine blood components largely inhibits the antibacterial activity of the peptide. On the contrary, in human serum and plasma Bac7(1-35) maintains its efficacy. This is due to the more rapid degradation by proteases of murine blood. The in vivo biodistribution of Bac7(1-35) was investigated by using a time-domain optical imaging apparatus and a fluorescently-labeled Bac7(1-35) derivative. The compound reaches the kidney and the bladder respectively 1 and 3 hours after i.p. injection. The in vivo and ex vivo analyses performed after 24 h confirm that the compound has been totally excreted. A mouse model of S. typhimurium infection was set up and used to test the therapeutic efficacy of Bac7(1-35). Treatment of infected mice with the peptide injected i.p. immediately after a lethal, intraperithoneal bacterial challenge, increased the mean survival time and reduced significantly the number of viable bacterial cells in liver and spleen of treated mice at 3 days post-inoculum. In 1/3 of the organ homogenates, the bacterial presence was undetectable and this result matches the percentage of cured animals (35%). In an attempt to improve its pharmacokinetic profile, the peptide was conjugated with polyethylene glycol (PEG), a non-toxic, non-immunogenic and FDA-approved polymer. Different strategies of pegylation have been considered to find the best method in terms of chemical yield and of maintenance of biological activity. Pegylation via a thioether ligation resulted the best strategy to obtain a slow active peptide release in human blood components with a reduced renal clearance and an increased bioavailability of Bac7(1-35), as biodistribution analyses demonstrated. Several important pathogens, such as S. enterica, cause disease by surviving and replicating within host cells. Since many AMPs have also immunomodulatory activities, we investigated the effect of Bac7(1-35) on the interaction between macrophages and Salmonella. We carried out phagocytosis assays with macrophages and the results suggest that Bac7(1-35) plays a positive modulatory effect on this function. Phagocytosis assays were also performed to determine if Bac7(1-35) could inhibit survival and replication of intracellular Salmonella. The results show that the peptide inhibits the replication of intracellular Salmonella, suggesting that it can exert its antibacterial activity within eukaryotic cells. Further studies are required to fully understand the details of the Bac7(1-35) biological activities. The results obtained provide encouraging evidence for future investigations on Bac7(1-35) and on the pegylated form Bac7(1-35)CAM-PEG20k also in other models of infection and with different intracellular pathogens.
XXIII Ciclo
1981
Silva, Osmar Nascimento. "Avaliação do potencial terapêutico e estudo da atividade imunomodulatória e antimicrobiana in vitro e in vivo de diferentes formas de clavaninas." Universidade Federal de Juiz de Fora (UFJF), 2010. https://repositorio.ufjf.br/jspui/handle/ufjf/4272.
Повний текст джерелаApproved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:47:58Z (GMT) No. of bitstreams: 1 osmarnascimentosilva.pdf: 3091891 bytes, checksum: 8e0f2ed0de0225b3ed16c08cdd6fee62 (MD5)
Made available in DSpace on 2017-05-12T15:47:58Z (GMT). No. of bitstreams: 1 osmarnascimentosilva.pdf: 3091891 bytes, checksum: 8e0f2ed0de0225b3ed16c08cdd6fee62 (MD5) Previous issue date: 2010-02-24
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
As infecções relacionadas à assistência à saúde (IrAS), são uma das principais causas de mortalidade e aumento dos custos hospitalares em países desenvolvidos e em desenvolvimento. Nos casos em que um paciente adquire uma IrA e esta não é tratada adequadamente, a mesma pode evoluir para um quadro mais grave, podendo levar a sepse e consequentemente na maioria dos casos a morte. A sepse representa um importante problema de saúde pública, entretanto, um tratamento eficaz para esta síndrome ainda não foi encontrado. Peptídeos antimicrobianos foram relatados para modular a resposta à infecção bacteriana na sepse, independente dos mecanismos de resistência conhecidos para os antibióticos. Desta forma, procurou-se investigar a atividade imunomodulatória de duas formas de clavaninas sobre monócitos RAW 264.7, bem como a atividade antimicrobiana e a citotoxicidade in vitro. Em ensaios in vivo a genotoxicidade, a ação das clavaninas sobre a migração de neutrófilos e a eficácia do tratamento com as clavaninas em um modelo de infecção de ferida operatória por S. aureus e sepse polimicrobiana grave também foram avaliadas. Os estudos in vitro demostraram que as clavaninas inibiram completamente o crescimento de E. coli, K. pneumoniae e S. aureus, preveniram a secreção de citocinas pró-inflamatórias (TNF-α, IL-12) e NO, e aumentaram a secreção de IL-10. Além disso, as clavaninas não apresentaram atividade citotóxica sobre as células RAW 264.7. Nos experimentos in vivo, as clavaninas não apresentaram genotoxicidade, além de apresentarem-se quimoatraentes para neutrófilos. As clavaninas, também, reduziram significativamente as unidades formadoras de colônias de S. aureus no modelo experimental de ferida operatória, e reduziram a mortalidade dos animais sépticos em mais de 50%, quando comparados com animais controle. Devido à sua ação direta sobre células do sistema imune e microorganismos, as clavaninas aparentam ser compostos potenciais para o tratamento de infecções bacterianas graves como a sepse, demonstrando alto valor biotecnológico.
Healthcare-associated infections (HAIs) are a major cause of mortality, also increasing hospital costs in developed and developing countries. When a patient acquires HAIs and this is not properly handled, disease may clearly worst, leading to sepsis and consequently in major to death. Despite of sepsis represents an important public health problem, any effective treatment for this syndrome was obtained until now. In this view, antimicrobial peptides have been reported as modulators of immune response to bacterial infection in sepsis, with independent activity of mechanisms that lead to antibiotic. Thus, the immunomodulatory activity of two different forms of clavanins over RAW 264.7 monocytes, as well the in vitro antimicrobial and cytotoxic activities were here investigated. Furthermore, in vivo genotoxicity assays, the evaluation of clavanins activity on neutrophil migration and also the efficacy of treatment with clavanins in a wound S. aureus infection model and severe polymicrobial sepsis were also evaluated. Moreover, in vitro studies demonstrated that clavanins are able of inhibit the growth of E. coli, K. pneumoniae and S. aureus. Clavanins also prevented the secretion of proinflammatory cytokines (TNF-α, IL-12) and NO, and increased the IL-10secretion. In addition, clavanins showed none cytotoxicity on RAW 264.7 cells. During in vivo experiments, the clavanins showed no genotoxicity, showing however, a clear chemotactic effect for neutrophils. Clavanins also significantly reduced the colony-forming units of S. aureus in an experimental model of surgical wound infection and reduced the mortality of septic animals in more than 50 %, when compared to control group. Due to their direct activities over immune cells and microorganisms, clavanins are potential compounds for the treatment of serious bacterial infections such as sepsis, showing an enormous and remarkable biotechnological value.
Bürkle, Carl-Philipp Stavros. "Die Expression antimikrobieller Peptide (Psoriasin, HBD-2 und HBD-3) in menschlicher Haut und deren Modulation in vivo - eine Untersuchung im xenogenen Haut-Transplantationsmodell." Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-73827.
Повний текст джерелаBorrelli, Alexander P. "Synthetic Genes for Antimicrobial Peptides." Digital WPI, 2003. https://digitalcommons.wpi.edu/etd-theses/427.
Повний текст джерелаBorelli, Alexander P. "Synthetic genes for antimicrobial peptides." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0428103-102059/.
Повний текст джерелаVaucher, Rodrigo de Almeida. "Influência do peptídeo P34 na expressão gênica em Listeria spp. e estudo da citotoxicidade dos peptídeos P34 e P40." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/23977.
Повний текст джерелаIn this study initial experiments were performed to evaluate synergistic action of the antimicrobial peptide P34 and culture supernatants of some selected lactic acid bacteria isolated from Minas Frescal cheese. The influence of this peptide in the expression of genes in L. monocytogenes and L. seeligeri, their cytotoxicity in differents eukaryotic cells and “in vivo” toxicity was investigated. Also, some tests were carried out o evaluate the cytotoxicity of the antimicrobial peptide P40. The peptide P34 caused a decrease of up to 3 log cycles in viable counts of L. monocytogenes artificially inoculated in cheese. A significant increase in expression of genes dltA, Imo1695 mptA of L. monocytogenes was observed after 96 h incubation of the peptide P34 in cheese. The influence of peptide P34 on the expression of genes associated to components of cell envelope of L. monocytogenes and L. seeligeri, promoted a non significant increase in the levels of transcription of genes dltA, Imo1695 and mptA were observed after incubation of L. monocytogenes for 24 hs at 37°C and 240 hs at 4°C in plates. In L. seeligeri a significant decrease was observed in gene expression dltA. The gene Imo1695 showed a significant decrease in its expression (2000-fold) after inoculation with the peptide P34. A significant decrease of expression was also observed for the gene mptA (31872 - times) after inoculation with the peptide P34 and incubation for 24 hours at 37°C. The inoculation of the plate with the P34 peptide and incubated for 240 hrs at 4°C, showed a non-significant decrease of gene expression. The cytotoxicity of the peptide P34 and P40 was assessed in VERO cells treated with different concentrations (0.02 - 2.5 μg ml- 1). In MTT, NRU and LDH assays the EC50 to the peptide P34 were 0.60, 1.25, 0.65 μg ml-1 and the peptide P40 were 0.30, 0.51 and 0.57 μg ml-1, respectively. The hemolytical activity on human erythrocytes was of (5.8%) and (19%), respectively. The effects on viability, motility and acrosomal exocytosis of humam sperm were also evaluated for peptideP34. There were no hypersensitivity reactions or significant increase in antibody titer during the immunogenicity experiment or death of animals during the acute or subchronic toxicity tests. The LD50 was more the 332.3 ± 0.76 mg/kg. No significant changes in the serum biochemical parameters were observed in the animals treated with the peptide P34. Signs of possible toxicity were no detected in animals in the group treated with 0.825 mg/kg day of peptide P34. In this group only histological changes in the spleen with the presence of megakaryocytes were observed. From these results show the potential o peptide P34 to be used in future as biopreservative in foods.
Vargues, Thomas. "Antimicrobial peptides : structure, function and resistance." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4076.
Повний текст джерелаZhao, Hongxia. "Mode of action of antimicrobial peptides." Helsinki : University of Helsinki, 2003. http://ethesis.helsinki.fi/julkaisut/laa/biola/vk/zhao/.
Повний текст джерелаParisi, Rosaura. "Computational design of new antimicrobial peptides." Doctoral thesis, Universita degli studi di Salerno, 2018. http://hdl.handle.net/10556/3018.
Повний текст джерелаAntimicrobial peptides (AMP) are evolutionarily conserved components of the innate immune system. They have a broad spectrum of action against bacteria, fungi and viruses. Therefore, AMP are studied as probable substitutes of the traditional antibiotics, for which most pathogens have developed resistance. The main objective of this work was the design of novel linear peptides capable to interact with the cellular membrane of the common pathogens. In this work, sequences of active AMP were carefully obtained from the scientific literature and collected in Yadamp (http://yadamp.unisa.it/), a database of AMP created recently in the laboratory where this project was carried out. In Yadamp, there are information about peptides name, amino acid sequence, length, presence of disulfide bridges, date of discovery, activity and taxonomy. The most relevant chemical-physical properties are also listed. This database is mainly focused on the peptides activities. Experimental MIC values (the lowest concentration of an antimicrobial that inhibits the visible growth of a microorganism) are constantly obtained from careful reading the original papers. In this work, a great contribution was made in the enrichment of the database. In fact, 1009 sequences were added to Yadamp. It currently contains 3142 AMP sequences. For these AMP, 573 molecular descriptors were calculated. In addition, this project also involved the search for new molecular descriptors. Yadamp is a resource for QSAR investigations on AMP. It allows to create subsets of AMP, homogeneous in one, two or more parameters...[abstract by Author]
XXX ciclo
Díaz, i. Cirac Anna. "Mechanism of action of cyclic antimicrobial peptides." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/38252.
Повний текст джерелаAquesta tesi doctoral resulta de la combinació d’estudis mitjançant tècniques experimentals i computacionals amb l’objectiu d’entendre el mecanisme d’acció de "de novo" decapèptids cíclics amb elevada activitat antimicrobiana. Experimentalment, es va avaluar la influència de la substitució dels residus de fenilalanina per triptòfan en la seva activitat antimicrobiana i també la seva estabilitat sèrum humà, per tal de valorar la seva possible aplicació terapèutica envers el càncer. Per altra banda, es va simular la interacció del pèptid BPC194 c(KKLKKFKKLQ), millor candidat de la biblioteca de pèptids cíclics, amb models aniònics de bicapa lipídica. Els resultats van posar en manifest una relació estructura-funció derivada de la conformació estable dels pèptids que participen directament en la permeabilització de la membrana. Es va procedir doncs al disseny racional de nous pèptids cíclics sent el pèptid BPC490 el que va presentar una millor activitat bacteriana en comparació amb el pèptid més actiu de la llibreria original.
Bunkóczi, Gábor. "Structure determination of peptides with antimicrobial action." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974033650.
Повний текст джерелаLu, Shanshan. "Immobilization of antimicrobial peptides onto titanium surfaces." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/12622.
Повний текст джерелаNeville, Frances Clare. "Interaction of antimicrobial peptides with bacterial membranes." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439597.
Повний текст джерелаChau, Tanguy. "Delivery, design, and mechanism of antimicrobial peptides." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62063.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references.
Each year, 2 million people contract hospital-acquired bacterial infections, which causes the death of 100,000 patients and costs the US healthcare system over $21 billion. These infections have become dangerously resistant to our existing line of antibiotics and are rapidly spreading outside of hospitals and into communities. As molecular targets to develop new antibiotics are becoming exhausted, clinicians and scientist are concerned that antibiotic resistant infections will wipe out most of the major health benefits acquired over the last century. The work described in this thesis develops new antimicrobials strategies against bacterial infections, focusing on antimicrobial peptides (AmPs). We first delivered genes inducing the toxic expression of AmPs and other lytic agents directly into bacteria using re-engineered bacteriophages. Expression of these lytic agents in lysogenic bacteriophages resulted in bactericidal activity, and demonstrated, for the first time, a long-term cidal effect for over 20 hours. We then enhanced the efficacy of our approach by expressing the same agents in lytic bacteriophage, which resulted in complete suppression of the bacterial culture and prevented bacterial regrowth and resistance to bacteriophages. Since a large fraction of medical infections originates at the surface of implantable devices, we developed film coatings that release active AmPs to cover these surfaces and prevent bacterial colonization. We incorporated AmPs in layer-by-layer films and demonstrated that the kinetics of AmP release can be adjusted. These released AmPs still actively prevented bacterial growth and remained non-toxic towards mammalian cells. While natural AmPs have broad activity against pathogens, they are not optimized for a specific antimicrobial function or bacterial target. Thus, researchers have tried for decades to design highly active and specific de novo AmPs. One approach is to design new peptides using conserved motifs identified from the amino acid sequence of natural AmPs. We improved this approach by measuring the antimicrobial activity of a large database of natural AmPs and incorporating this activity information in the design algorithm. This strategy improved the success rate of designing de novo peptides from 45% to 73% and increased the antimicrobial strength of the designed peptides. Finally, we developed new potentiating strategies by studying the mode-of-action of the family of ponericin AmPs. First, we measured their cidal behavior and differentiated bactericidal ponericins from bacteriostatic ones. Using a modified AFM and a microfluidic device, we observed that the action of AmPs led to cellular death through the corrugation of bacterial, while subpopulation of cells resisted the action of the AmPs longer than others. Focusing on the ponericin G1 AmP, we correlated these visual observations with various membrane stress sensing mechanisms. We concluded that bacteria's ability to develop resistance to ponericin G1 requires the sensing and repair of misfolded membrane proteins via the CpxAR system, as well as DNA repair via induction of the SOS response by RecA. Using microarrarys, we showed that ponericin G1 targets tRNA synthetases in the ribosome. Finally, we demonstrated 99.999% killing of antibiotic resistant bacteria by potentiating ponericin G1 with the ribosomal antibiotic kanamycin, whereas no killing is observed when these two agents are applied independently. untreta The PhDCEP capstone requirement finalizes the work of this thesis by analyzing market entry and expansion strategies for an antimicrobial company commercializing genetically engineered bacteriophages. In conclusion, this thesis establishes new advances in the delivery, the design and the potentiation of AmPs in order to eradicate resilient bacterial infections.
by Tanguy Chau.
Ph.D.
Jodoin, Joelle. "Histone H5: Bioinspiration for Novel Antimicrobial Peptides." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36976.
Повний текст джерелаArouri, Ahmad. "Interaction of antimicrobial peptides with model lipid membranes." kostenfrei, 2009. http://nbn-resolving.de/urn:nbn:de:gbv:3:4-540.
Повний текст джерелаSOLLAMI, DELEKTA SZYMON. "Hexosomes as Drug Delivery Vehicles for Antimicrobial Peptides." Thesis, KTH, Skolan för kemivetenskap (CHE), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172360.
Повний текст джерелаWarfield, Rachel. "Internally quenched peptides as substrates for antimicrobial enzymes." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436725.
Повний текст джерелаLoose, Christopher (Christopher R. ). "The production, design and application of antimicrobial peptides." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/38969.
Повний текст джерелаIncludes bibliographical references (p. 248-268).
With the spread of drug-resistant bacteria, existing antibiotics are losing their potency. Antimicrobial peptides (AmPs) represent an exciting class of drug candidates, particularly because their mechanism of action is unlikely to induce drug resistance. If resistance to AmPs were also slower to emerge in the clinic, they would have longer useful lifetimes than existing antibiotics. Nevertheless, a number of limitations exist for AmPs in the clinic. The high cost of peptide manufacture requires that highly potent sequences are created. Additionally, AmP selectivity must be improved if effective systemic doses are to be given without hemolytic activity or other toxicity. Improved high-throughput methods for AmP design or discovery could enable the achievement of both of these goals. To this end, we developed an approach based on the discovery of semi-conserved motifs across natural AmPs, which we demonstrated are associated with antimicrobial activity. Additionally, we created novel AmP formulations that may bypass some of these clinical limitations. In order to evaluate AmP design approaches, a high-throughput production and assay platform was created using in vitro translation. This technology may produce peptides that would be toxic to recombinant hosts and synthesize peptides of arbitrary length.
(cont.) The cost per peptide was minimized through a series of process improvements. First, we created methods to construct oligonucleotides that mimicked our motif-based design of AmPs. This approach allowed the reuse of primers for many peptides, reducing cost and enabling the study of pattern synergy. Additionally, we found peptide translation was enhanced by co-translating a fusion partner in frame with the AmP. The AmP could be freed from the fusion partner after translation using enterokinase digestion. Further, we increased yield 3-fold by optimizing the length of fusion partner. The partner was made as short as possible to limit the translational resources required to synthesize the fusion partner, while being long enough to ensure stability from proteases. The solubility of the fusion partner-AmP construct was also improved through the selection of a highly soluble partner of the optimal length. Finally, we developed a purification scheme to ensure that the in vitro translation extract would not impact measurement of antimicrobial activity. We also developed and evaluated the design of AmPs using semi-conserved motifs. We used a database of over 500 natural AmPs as a training set for pattern discovery.
(cont.) The resulting motifs were exhaustively recombined to create all 20 amino acid sequences that were entirely covered by these patterns. These sequences were clustered, and 42 diverse members selected for characterization using representative Gram negative and Gram positive bacteria. Approximately 50% of the designed AmPs were active against at least one of the bacteria at 256 ug/ml. Control peptides were created in which the amino acids in the designed peptides were rearranged such that they were not homologous to any antimicrobial motifs. Thus, these controls had the same bulk physiochemical properties frequently associated with antimicrobial activity as the designed sequences, but we hypothesized they would not be active because they did not match the antimicrobial motifs. In fact, only 5% of the control sequences had activity at 256 ug/ml, indicating that the antimicrobial motifs give a 10-fold enrichment in activity. Further, two highly active designed peptides had MICs of 16 ug/ml against Bacillus cereus and 64 ug/ml against Escherichia coli. Additionally, AmPs active against B. cereus were all active against the hospital pathogen Staphylococcus aureus, and the bioterror agent, Bacillus anthracis.
(cont.) Our motif-based design may be most effective as the first stage of a two-stage design tool. In the first stage, highly diverse leads with novel profiles are created and evaluated. Promising leads could then be optimized using a variety of techniques. By creating just 44 variants of one lead, we designed an AmP with broad spectrum activity that had MICs of 16 ug/ml against E. coli and 8 ug/ml against B. cereus and 4 ug/ml against S. aureus. Another approach to build on our design tool would be to incorporate activity and toxicity characteristics of members of the training set into the design or scoring of new sequences. In order to begin assembling this data using a standardized method, a representative set of 100 natural, linear AmPs was chosen through clustering. Their antimicrobial activity against E. coli, S. epidermidis, and S. aureus were evaluated, along with hemolytic activity. When further supplemented, this information may enable an improved scoring metric to be created. Additionally, we systematically demonstrated that amidating the c-terminus of natural AmPs improves both antimicrobial activity and therapeutic index. Finally, we recognized that AmP's mechanism of action would allow activity to be retained when they are permanently tethered to medical device surfaces.
(cont.) Unlike existing coatings which rely on the slow release of silver or other antibiotics, a permanently tethered approach could have a longer lifetime and reduced systemic toxicity concerns. A versatile chemistry was developed to create immobilized AmP coatings. These formulations had broad spectrum antimicrobial activity without significant hemolytic activity. Further, the coatings were effective through multiple bacterial challenges. The combination of the AmP design tool along with localized formulations represent a significant advance in the process of moving AmPs to the clinic to combat drug-resistant infections.
by Christopher Loose.
Ph.D.
Strauss, Joshua. "Investigating bacterial lipopolysaccharides and interactions with antimicrobial peptides." Worcester, Mass. : Worcester Polytechnic Institute, 2009. http://www.wpi.edu/Pubs/ETD/Available/etd-012009-120216/.
Повний текст джерелаDallon, Emma Kay. "Exploration of Antimicrobial Activity in Natural Peptides and High-Throughput Discovery of Synthetic Peptides." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7468.
Повний текст джерелаOkechuku, Adaora. "Determination of the mode of action of the antibacterial peptide ApoEdp." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/determination-of-the-mode-of-action-of-the-antibacterial-peptide-apoedp(1937bcc4-f28b-416e-8dd7-8d493082ac2a).html.
Повний текст джерелаZerfas, Breanna L. "Creating Novel Antimicrobial Peptides: From Gramicidin A to Screening a Cyclic Peptide Library." Thesis, Boston College, 2017. http://hdl.handle.net/2345/bc-ir:107444.
Повний текст джерелаAs the threat of microbial resistance to antibiotics grows, we must turn in new directions to find new drugs effective against resistant infections. Antimicrobial peptides (AMPs) and host-defense peptides (HDPs) are a class of natural products that have been well-studied towards this goal, though very few have found success clinically. However, as there is much known about the behavior of these peptides, work has been done to manipulate their sequences and structures in the search for more drug-like properties. Additionally, novel sequences and structures mimicking those seen in nature have been discovered and characterized. Herein, we demonstrate our ability to finely tune the antimicrobial activity of various peptides, such that they can be provided with more clinically desirable characteristics. Our results show that gramicidin A (gA) can be made to be less toxic via incorporation of unnatural cationic amino acids. This is achieved by synthesizing lysine analogues with diverse hydrophobic groups alkylated to the side-chain amine. Through exploring different groups, we achieved peptide structures with improved selectivity for bacterial over mammalian membranes. Additionally, we were able to achieve novel broad-spectrum gram-negative activity for gA peptides. In efforts to combat bacterial resistance to cationic antimicrobial peptides (CAMPs), we have directed our reported amine-targeting iminoboronate chemistry towards neutralizing Lys-PG in bacterial membranes. Originally incorporating 2-APBA into gA, we found this to hinder the peptide’s activity. However, we were successful in increasing the potency of gA3R, a cationic mutant of gA, towards S. aureus by using a co-treatment of this peptide with a Lys-PG binding structure. Currently, we are exploring this strategy further. Finally, we describe our work towards establishing a novel cyclic peptide library incorporating a 2-APBA warhead for iminoboronate formation with a given target. In this, we have achieved intermolecular reduction of iminoboronates, strengthening the stringency of library screening. Although we were unsuccessful in finding a potent hit for binding of the lipid II stem peptide, screening against human transferrin yielded selective hits. Currently we are investigating these hits to understand their activity and therapeutic potential
Thesis (PhD) — Boston College, 2017
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
Güell, Costa Imma. "Synthesis of antimicrobial peptides derived from BP100 and BPC194." Doctoral thesis, Universitat de Girona, 2012. http://hdl.handle.net/10803/69920.
Повний текст джерелаEn aquesta tesi doctoral es va estudiar la preparació en fase sòlida de pèptids antimicrobians derivats dels pèptids lead BP100 i BPC194. En primer lloc, es varen preparar derivats del pèptid lineal BP100 incorporant D aminoàcids en diferents posicions de la seqüència. A més, també es varen sintetitzar derivats d'aquest pèptid lead incorporant un anell de triazole a la cadena lateral de diferents aminoàcids. Posteriorment, es va procedir a l'estudi de la síntesi dd pèptids multivalents derivats de BPC194. Per aconseguir aquest objectiu es va portar a terme la síntesi de pèptids cíclics incorporant un anell de triazole a la cadena lateral d’aminoàcids amb diferents allargades de cadena. Finalment, va procedir a la preparació de carbopèptids contenint 2 i 4 unitats de BP100 i/o derivats. L’avaluació de l’activitat biològica dels pèptids sintetitzats va permetre idenficar seqüències actives enfront de bacteris fitopatògens i fongs i poc tòxiques enfront cèl•lules eucariotes.
Termén, Stefan. "Expression of cathelicidin antimicrobial peptides in man and rat /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7140-138-5/.
Повний текст джерелаShewring, Dawn M. "Fish antimicrobial peptides and the indentification of gadoid cathelicidins." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=185604.
Повний текст джерелаZhang, Ruowen. "Isolation and analysis of antimicrobial peptides from frog skins." Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534592.
Повний текст джерелаMorgan, Michelle Marie. "Interaction of Burkholderia cepacia complex organisms and antimicrobial peptides." Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540768.
Повний текст джерелаAlkassem, Hasan. "Imaging antimicrobial peptides in action by atomic force microscopy." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10043141/.
Повний текст джерелаMcQuade, Rebecca. "Clostridium difficile Responds to Antimicrobial Peptides and Oxidative Stress." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/578613.
Повний текст джерелаvan, Rensburg Wilma. "Characterization of natural antimicrobial peptides adsorbed to different matrices." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97929.
Повний текст джерелаENGLISH ABSTRACT: Biofouling is the attachment and biofilm formation that leads to negative repercussions such as persistent post-harvest infections, infections obtained from medical implants and continual surface contamination of food processing plants. Much of the problem lies with the resistance that develops against conventional treatments due to the formation of mature biofilms. Thus the focus has shifted from the removal of biofilms to the prevention of initial attachment of organisms. This entails the use of antimicrobial surfaces that either have an inherent antimicrobial activity, e.g. certain metals, or surfaces that are modified by the attachment of antimicrobial agents. The attachment of antimicrobial agents can either be through covalent bonding or adsorption, depending on the intended use of the surface as well as the mode of action of the antimicrobial agent. Antimicrobial peptides (AMPs) are ubiquitous in nature, tend to have a broad spectrum of activity, are very stable and have been shown to maintain activity when covalently bound to solid surfaces. Tyrocidines (Trcs), antimicrobial peptides produced by Bacillus aneurinolyticus, are cyclodecapeptides with a broad spectrum of activity against Grampositive bacteria, fungi, yeasts and the human malaria parasite, Plasmodium falciparum. The aim of this study was to determine the antimicrobial activity of surfaces treated with a tyrocidine extract, under which conditions the activity remained stable and to look into possible applications of these peptide-treated surfaces. The study focussed on different solid surfaces namely mixed cellulose, polyvinylidene fluoride, polycarbonate, cellulose acetate, cellulose (paper)(CL) and high density cellulose packing material (HDC), as a pilot study to assess the antimicrobial activity of Trc and gramicidin S (GS) treated solid surfaces. Peptide desorption and subsequent analysis by mass spectrometry was used to confirm the presence and integrity of the Trcs adsorbed. Scanning electron microscopy was utilised to show that the adsorbed peptides did not affect the structural integrity of the treated filters. However, it was shown that the adsorbed peptides changed the hydrophobic/hydrophilic character by means of a wettability assay. A cell viability assay and erythrocyte assay were developed from existing methodologies to determine the biological activity of the AMP-functionalised polymeric material. Seven of the AMP treated solid surfaces showed antimicrobial activity when challenged with >105 Micrococcus luteus cells/cm2. Although the polycarbonate filter lost antimicrobial activity at the high cell concentrations, it was shown to have potent antimicrobial activity at lower cell concentrations. Complete inhibition of M. luteus growth was observed for both the gramicidin S and tyrocidine extract treated high density cellulose and cellulose filters. Stability tests showed that the tyrocidines remained adsorbed to cellulose filters and biologically active when exposed multiple water washes, water washes at different temperatures (25°C - 100°C) and pH changes (pH 1-12). The antimicrobial activity was only affected after exposure to the water wash of pH 13 which is possible due to susceptibility of the CL filters to high pH solvents. A preliminary study on the effect of Trcs treated CL filters on the sterilization, germination and effect on tomato seedlings was conducted. It was found that Trcs had no effect on the germination and did not fully sterilise the seeds or environment against fungi. However, it was observed that 5 μg/mL Trcs treated filters promoted root length opposed to the toxic effect seen with filters treated with higher Trc concentrations. It is hypothesised that Trcs prefer to bind to hydrophilic surfaces exposing the hydrophobic residues and the cationic residue of the peptide to interact with the bacterial membrane to elicit its antimicrobial response. The exposed residues contain some of the hydrophobic residues and the cationic Orn9/Lys9, which are crucial to the antimicrobial activity of the peptides. Hydrophobic interaction is particularly important for the haemolytic activity which is currently the only viable method of detection of the adsorbed Trcs. Trcs also have a preference for adsorption onto cellulose and cellulose analogues which points to possible application in protective food wrapping and wood surface protection. Trcs maintains its antimicrobial activity regardless of adsorption to solid surfaces. It can therefore be concluded that Trcs treated solid surfaces hold great potential in preventing the initial bacterial colonization and subsequent biofilm formation. Antimicrobial peptide enriched solid surfaces can thus be developed and tailored to a specific application such as filters, catheters and packaging materials.
AFRIKAANSE OPSOMMING: Biovervuiling is die aanhegting en vorming van biofilms met negatiewe gevolge soos aanhoudende na-oes infeksies, infeksies op mediese inplantings en voortdurende oppervlak besoedeling van voedselverwerkings fabrieke. Die probleem lê grotendeels by die weerstand wat ontwikkel word teen konvensionele behandelings as gevolg van die vorming van volwasse biofilms. Die fokus het gevolglik verskuif vanaf die verwydering van biofilms na die voorkoming van aanvanklike aanhegting van organismes aan oppervlaktes. Dit behels die gebruik van antimikrobiese oppervlaktes wat of 'n inherente antimikrobiese aktiwiteit het, bv. sekere metale óf oppervlaktes wat aangepas is deur die aanhegting van antimikrobiese middels. Die aanhegting van antimikrobiese agente kan of deur kovalente binding óf adsorpsie plaasvind, afhangende van die beoogde gebruik van die oppervlak, sowel as die metode van werking van die antimikrobiese agent. Antimikrobiese peptiede (AMPe) is alomteenwoordig in die natuur, is geneig om 'n breë spektrum van aktiwiteit te hê, is baie stabiel en het getoon dat aktiwiteit in stand gehou word wanneer dit kovalent gebind word op soliede oppervlaktes. Tirosidiene (Trcs), antimikrobiese peptiede wat deur Bacillus aneurinolyticus geproduseer word, is siklodekapeptiede met 'n breë spektrum van aktiwiteit teen Gram-positiewe bakterieë, swamme, giste en die menslike malaria parasiet Plasmodium falciparum. Die doel van hierdie studie was om die antimikrobiese aktiwiteit te bepaal van oppervlaktes wat met 'n tirosidien ekstrak behandel is, te bepaal onder watter omstandighede die aktiwiteit stabiel bly en om te soek na moontlike toepassings van hierdie peptied-behandelde oppervlaktes. Die studie het gefokus op verskillende soliede oppervlaktes naamlik gemengde sellulose, polyvinylidene fluoried, polikarbonaat, sellulose asetaat, sellulose (papier)(CL) en 'n hoë digtheid sellulose verpakkings materiaal (HDC), as 'n loodsstudie om die antimikrobiese aktiwiteit van die Trcs en gramisidien S (GS) behandelde soliede oppervlaktes te ondersoek. Peptied-desorpsie en daaropvolgende ontleding deur massaspektroskopie is gebruik om die teenwoordigheid en integriteit van die geadsorbeerde Trcs te bevestig. Skandering elektronmikroskopie is gebruik om aan te toon dat die geadsorbeerde peptiede geen invloed op die strukturele integriteit van die behandelde filters het nie. Daar is egter getoon dat die geadsorbeerde peptiede die hidrofobiese / hidrofiliese karakter verander. „n Lewensvatbaarheid selgebaseerde toets en eritrosiet toets is ontwikkel uit bestaande metodes om die biologiese aktiwiteit van die AMP-gefunktionaliseerde polimeriese materiaal te bepaal. Sewe van die AMP behandel soliede oppervlaktes het antimikrobiese aktiwiteit getoon wanneer dit met > 105 Micrococcus luteus selle/cm2 gedaag is. Hoewel die polikarbonaat filter antimikrobiese aktiwiteit met hoë sel konsentrasies verloor het, is dit getoon dat dit wel uitgeproke antimikrobiese aktiwiteit het teen laer konsentrasies selle. Volledige inhibisie van M. luteus groei is waargeneem vir beide die hoë digtheid sellulose en sellulose filters wat met GS en tirosidien ekstrak behandel is. Stabiliteit toetse het getoon dat die tirosidiene geadsorbeer en biologies aktief op sellulose filters bly nadat dit blootgestel is aan verskeie water was-stappe, waterwasse by verskillende temperature (25 °C -100 °C) en pH veranderinge (pH 1-12). Die antimikrobiese aktiwiteit was net beïnvloed ná blootstelling aan die water met 'n pH 13, wat moontlik is te danke aan die vatbaarheid van die CL filters by hoë pH oplosmiddels is. 'n Voorlopige studie is gedoen om die uitwerking van Trcs behandelde CL filters op die sterilisasie, ontkieming en tamatiesaailinge te bepaal. Daar is gevind dat Trcs geen effek op die ontkieming het nie, maar dat dit nie volledig die sade en omgewing steriliseer vir fungiese groei nie. Daar is egter waargeneem dat 5 μg/mL Trcs behandelde filters wortel lengte van die saailinge bevorder teenoor die giftige uitwerking soos waargeneem vir die filters wat met hoër konsentrasies Trcs behandel is. Dit word gepostuleer dat Trcs verkies om aan hidrofiliese oppervlaktes te bind wat die van die hidrofobiese aminosure en die kationiese residu van die peptied blootstel om aan die bakteriële membraan te bind om gevolglik antimikrobiese reaksie te ontlok. Die blootgestelde deel bevat sommige van die hidrofobiese residue en positiewe Orn9/Lys9 wat noodsaaklik vir die antimikrobiese aktiwiteit van die peptiede. Die hidrofobiese interaksies is veral belangrik vir die hemolitiese aktiwiteit wat tans die enigste bruikbare metode van opsporing van die geadsorbeerde Trcs is. Trcs het ook 'n tendens vir adsorpsie op sellulose en sellulose analoë wat dui op die moontlike toepassing in beskermende voedselverpakking en die beskerming van houtoppervlaktes. Trcs handhaaf hul antimikrobiese aktiwiteit, ongeag van adsorpsie aan soliede oppervlaktes. Dit kan dus afgelei word dat Trcs-behandelde soliede oppervlaktes die potensiaal het om die aanvanklike kolonisasie van bakterië te voorkom en die daaropvolgende biofilm vorming. Antimikrobiese peptied verrykde soliede oppervlaktes kan dus ontwikkel en aangepas word vir gebruik in spesifieke toepassing soos in filters, kateters en verpakkingsmateriaal.
Peel, Emma Jane. "Peptides from the Pouch: Marsupial and Monotreme Cathelicidins." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/17934.
Повний текст джерелаNg, Choi I.-teng Montserrat. "Solid-phase synthesis of 5-arylhistidine-containing peptides: from linear antimicrobial peptides to cyclic peptides derived from arylomycins and aciculitins." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/380739.
Повний текст джерелаLa incorporació de sistemes biarílics asimiètrics en seqüències peptídiques es considera un enfocament útil per a millorar l'activitat biològica de pèptids. Tenint en compte la dificultat d'arilar la posició 4 (5) de l'anell d'imidazole, aquesta tesi doctoral es centra en el desenvolupament de noves estratègies eficients per a la preparació en fase sòlida d'undecapèptids antimicrobians contenint una 5-arilhistidina a través d'una reacció de Suzuki-Miyaura sota irradiació microones. L'extensió d'aquesta metodologia ha permès la síntesi de pèptids biarílics cíclics de diferents mides que incorporen un enllaç His-Phe 0 His-Tyr. Posteriorment, s'ha desenvolupat un procediment per la síntesi total en fase sòlida de lipopèptids biarílics cíclics derivats de les arilomicines. Les estratègies anteriors s'han estès a la preparació de compostos biarílics anàlegs dels pèptids bicíclics marins aciculitines. Concretament, s'ha preparat anàlegs dels hemisferis nord i sud de las aciculitines així com pèptids biarílics bicíclics que incorporen un pont Phe-Phe, Phe-Tyr, Tyr-His 0 Tyr-Tyr.
Montesinos, Barreda Laura. "Rice seeds as biofactories of the production of antimicrobial peptides." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/135054.
Повний текст джерелаUna sèrie de pèptids antimicrobians (PAMs) derivats del pèptid BP134 (provinent de la quimioteca CECMEL11), que exhibien un potent efecte bactericida i baixa citotoxicitat, es van seleccionar per a l'expressió en arròs. Es van generar plantes transgèniques que expressaven les seqüències gèniques corresponents als PAMs, i adaptades a l’ús de codons, sota el control de promotors específics de llavor. Es va confirmar que els PAMs esperats s’acumulaven en les llavors, però no en altres teixits de la planta, i conferien una protecció molt significativa a la infecció per patògens fúngics i bacterians de plantes. La purificació dels PAMs es va realitzar mitjançant solubilització/precipitació selectiva/ i cromatografia de Bescanvi Catiònic Feble i Fase Reversa. Un dels pèptids obtinguts, S-Cec A, exhibia una potent activitat antibacteriana i bactericida contra Dickeya sp. Els nivells d'acumulació dels PAMs en les llavors eren dependents de l'estratègia utilitzada. La llavor d’arròs ofereix una plataforma adequada pel seu ús com a biofactoria de PAMs
Harris, Mark R. "Effects of cationic antimicrobial peptides on Candida and Saccharomyces species." Thesis, St Andrews, 2010. http://hdl.handle.net/10023/881.
Повний текст джерелаGabere, Musa Nur. "Prediction of antimicrobial peptides using hyperparameter optimized support vector machines." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7345_1330684697.
Повний текст джерелаAntimicrobial peptides (AMPs) play a key role in the innate immune response. They can be ubiquitously found in a wide range of eukaryotes including mammals, amphibians, insects, plants, and protozoa. In lower organisms, AMPs function merely as antibiotics by permeabilizing cell membranes and lysing invading microbes. Prediction of antimicrobial peptides is important because experimental methods used in characterizing AMPs are costly, time consuming and resource intensive and identification of AMPs in insects can serve as a template for the design of novel antibiotic. In order to fulfil this, firstly, data on antimicrobial peptides is extracted from UniProt, manually curated and stored into a centralized database called dragon antimicrobial peptide database (DAMPD). Secondly, based on the curated data, models to predict antimicrobial peptides are created using support vector machine with optimized hyperparameters. In particular, global optimization methods such as grid search, pattern search and derivative-free methods are utilised to optimize the SVM hyperparameters. These models are useful in characterizing unknown antimicrobial peptides. Finally, a webserver is created that will be used to predict antimicrobial peptides in haemotophagous insects such as Glossina morsitan and Anopheles gambiae.
Pränting, Maria. "Bacterial Resistance to Antimicrobial Peptides : Rates, Mechanisms and Fitness Effects." Doctoral thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-130168.
Повний текст джерелаSeefeldt, Alexandra. "Inhibition of the bacterial ribosome by nascent and antimicrobial peptides." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0856/document.
Повний текст джерелаThe bacterial (70S) ribosome catalyzes peptide bond formation and represents a major target for antibiotics. The synthesized peptide passes through the exit tunnel of the large ribosomal subunit before it is released into the cytoplasm. Specific peptides can inhibit translation by acting in cis (nascent peptide) or in trans (proline-rich antimicrobial peptides; PrAMPs) due to interactions with the tunnel. PrAMPs were reported to inhibit protein biosynthesis and bind to the 70S ribosome. During my thesis, I solved the crystal structures of four different PrAMPs in complex with the bacterial ribosome, revealing that all peptides cover the peptidyl transferase center (PTC) and bind in a reverse orientation within the exit tunnel relative to a nascent chain. From this, I concluded that PrAMP binding inhibits the transition from initiation towards elongation. Nascent chain-mediated translational arrest occurs when a nascent peptide interacts with the exit tunnel, leading to the rearrangement and inactivation of the PTC. Arrest can be solely due to the peptide’s sequence or may require a small molecule co-inducer, such as a drug. The underlying mechanisms of action for short arrest peptides (polyproline or M+X(+) motifs) remain unknown. In order to study these short arrest peptides biochemically and structurally, I adopted a strategy to form arrested ribosomal complexes through the direct addition of the arrest peptidyl moiety to tRNAiMet with the help of a small ribozyme known as flexizyme. I was able to solve the cryo-EM structure of a ribosome arrested by an M+X(+) motif in the presence of erythromycin and to propose a model for the allosteric inactivation of the PTC
Karlsson, Jenny. "Regulation and characterization of antimicrobial peptides in man and mice /." Stockholm : Karolinska institutet, 2007. http://diss.kib.ki.se/2007/978-91-7357-286-6/.
Повний текст джерелаPritchard, Kevin. "The development of novel antimicrobial peptides with activity against MRSA." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/11609/.
Повний текст джерелаIyer, Abhishek. "DNA recognition and antimicrobial compounds : exploring the versatility of peptides." Thesis, University of Lincoln, 2016. http://eprints.lincoln.ac.uk/28664/.
Повний текст джерелаLofton, Tomenius Hava. "Mechanisms and Biological Costs of Bacterial Resistance to Antimicrobial Peptides." Doctoral thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-284119.
Повний текст джерелаHe, Jing. "Design and Study of Novel Antimicrobial Peptides with Proline Substitution." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1257779581.
Повний текст джерелаMankoci, Steven Gerald. "The Investigation of Water-Soluble Polyurethanes that Mimic Antimicrobial Peptides." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1524649965130039.
Повний текст джерелаFelek, Arif. "Discovery of antimicrobial peptides active against antibiotic resistant bacterial pathogens." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/discovery-of-antimicrobial-peptides-active-against-antibiotic-resistant-bacterial-pathogens(cc408f16-e24a-4f49-ac8e-e7a5fe7185d0).html.
Повний текст джерелаYu, Guozhi [Verfasser]. "Antimicrobial peptides: pharmacodynamics, combinatorial effects and resistance evolution / Guozhi Yu." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1150238127/34.
Повний текст джерелаROVERSI, DANIELA. "Mechanism of action of antimicrobial peptides: pore formation and beyond." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2013. http://hdl.handle.net/2108/202115.
Повний текст джерелаKwok, Hoi-shan, and 郭凱珊. "The comparison of biological properties of L- and D-enantiomeric antimicrobial peptides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206507.
Повний текст джерелаpublished_or_final_version
Pharmacology and Pharmacy
Master
Master of Medical Sciences
Matougui, Nada. "Development and characterization of antimicrobial peptides loaded lipid nanocapsules to treat bacterial infections." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0069.
Повний текст джерелаThe rapid increase in drug-resistant infections presents an acute problem in the healthcare sector, generating interest in novel antimicrobial strategies. The aim of this work is to explore the potential of lipid nanocapsules (LNCs) for Antimicrobial peptides (AMPs) delivery. Firstly, the experiments were focused on the development and optimization of AMP-loaded LNCs. Different strategies were investigated to deliver AA230,LL37 and DPK060 using LNCs (peptides adsorption atthe surface or encapsulated in the core of modified LNCs). The results demonstrated an association efficiency of 20 to 40%, when peptide is adsorbed, and over 80% encapsulation efficiency, when peptides are encapsulated. The second part concerned the study ofthe influence of peptides loading on their activity and stability against proteases. The results showed that peptides adsorption induced a potentiation of the antimicrobial activity of the native peptides, with a partial protection against proteolytic degradation. Conversely, peptides encapsulation allowed better peptide stability, correlated with higher encapsulation efficiencies and a preservation of the in vitro antimicrobial activity. In a third part, the mechanisms involved in LNC/AMP interactions and the complex interaction with model bacterial membrane have been evaluated. It has shown that structure and flexibility at solid-liquid interfaces govern peptide adsorption on the surface of the LNCs, which in turn is expected to change LNCs properties and interaction with bacterial membranes. Taken together, these results demonstrate the potential of LNCto deliver AMPs as an alternative anti-infective therapy