Antimicrobial Peptides and their Synthetic Mimics - Investigating the Mechanism o

抗菌肽及其合成模拟物 - 研究其作用机制

• 批准号: 7382929
• 负责人: David Gidalevitz
• 金额: $ 29.29万
• 依托单位: ILLINOIS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7382929
• 关键词: Advanced Development; Air; Anti-Bacterial Agents; Antibiotics; Antimicrobial Resistance; Antiviral Agents; Bacteria; Binding; Biological Assay; Biological Availability; Biomimetics; California; Cell Wall; Cell membrane; Cells; Chemistry; Chicago; Cholesterol; Circular Dichroism; Class; Clinical Research; Collaborations; Communicable Diseases; Comparative Study; Cytolysis; Cytoskeleton; Data; Development; Disease; Disruption; Drug usage; Endopeptidases; Engineering; Erythrocytes; Event; Fluorescence; Funding; Gram-Negative Bacteria; Gram-Positive Bacteria; Helix (Snails); Human; Illinois; Immune; Immune system; Incidence; Institutes; Knowledge; Laboratories; Left; Lipid Bilayers; Lipids; Liquid substance; Los Angeles; Lytic; Mediating; Membrane; Membrane Lipids; Membrane Proteins; Methodology; Methods; Microscopy; Molecular; Mono-S; Multi-Drug Resistance; Mutation; N-substituted Glycines; Nature; Neutrons; Numbers; Oligonucleotides; Peptide Antibiotics; Peptide Hydrolases; Peptides; Peptoids; Pharmaceutical Preparations; Pharmacologic Substance; Phosphatidyl glycerol; Phosphatidylglycerols; Physics; Plasma Cells; Polymers; Property; Protozoa; Range; Reporting; Request for Proposals; Research; Research Personnel; Research Project Grants; Resistance; Resolution; Roentgen Rays; Role; Science; Solid; Solutions; Staging; Structure; Structure-Activity Relationship; Surface; Synchrotrons; System; Techniques; Technology; Therapeutic; Today; Universities; Vesicle; Viral; Virus; Water; Work; X ray diffraction analysis; X-Ray Diffraction; analog; antimicrobial; antimicrobial drug; antimicrobial peptide; aqueous; bacterial resistance; base; design; drug resistant bacteria; ear helix; fungus; immunogenicity; infrared spectroscopy; interest; microbicide; mimicry; monolayer; novel; novel strategies; pathogenic bacteria; receptor; self assembly; solid state; viral envelope lipids

DESCRIPTION (provided by applicant): Antimicrobial peptides (AMP) form a first line of defense of the innate immune system and have a broad spectrum of microbicidal activity against a wide range of Gram-negative and Gram-positive bacteria, fungi, protozoa, and even enveloped viruses. Recently they became a matter of increasing interest because of their excellent potential in treating diseases which cannot be cured by conventional antibiotics due to antimicrobial resistance. AMPs either induce membrane damage that is a lethal event for target bacteria or bind to several targets in the cytoplasmic region of the bacteria. All the evidence indicates that the action of the AMPs does not involve stereospecific protein-receptor recognition, since the interactions of AMPs with their targets are generally considered to be nonspecific. Therefore, the character of AMP interaction with bacterial cell wall lipids, viral envelope, or native plasma cell membrane lipids largely determine their lytic potential. As part of our study, novel planar biomimetic membranes, both at air-water and solid-liquid interface will be developed. This will allow use of highly sensitive structural experimental techniques, which cannot be employed with vesicle systems nor with real cells. Furthermore, in addition to AMP we also plan to investigate membrane interactions of their synthetic peptoid mimics (ampetoids), which have an advantage of being protease-resistant, while showing high potency and selectivity as antimicrobial agents. In this highly interdisciplinary proposal we plan to use cutting edge synchrotron X-ray scattering techniques, which together with AFM and epifluorescence studies will yield near atomic resolution of peptide-lipid interaction. These data will be used to advance the understanding of AMP and ampetoids mode of action which can be used to develop rational design strategies for AMPs and antimicrobial peptide mimics to advance development of highly potent drugs that are effective even against multidrug resistant bacteria and viruses. Specific aims of this project are: (1) Examine the modes of interaction of ampetoids and natural AMPs with lipid monolayers representing an outer leaflet of red blood cell membranes and surface layer of bacterial cell wall using synchrotron grazing incidence X-ray diffraction, X-ray reflectivity, epifluorescence microscopy, and AFM used in complementary manner. (2) Design novel fluid bilayer membranes at the air-water interface, use them to examine the interaction of AMPs and ampetoids with both leaflets of bilayer membrane. (3) Design novel cholesterol tethered bilayer lipid membranes (tBLM) with cytoskeleton component. Examine mechanism of AMPs and ampetoids interaction with these tBLMs and elucidate role of cytoskeleton in their interactions. The broader impact of the proposed research is to advance development of novel antibiotic and antiviral drugs that will be immune to bacterial and viral mutations. Antimicrobial peptides and their synthetic mimics have enormous potential with regard to bacterial resistance because they interact not only with specific membrane protein receptors, but also with the lipid matrix of cell membranes, whose lipid composition is highly unlikely to change as a result of bacterial mutation. Better understanding of antimicrobial peptides and peptoids mode of action on molecular level could enhance the design and development of potent alternatives to the conventional antibiotics and antiviral drugs used today.

描述（由申请人提供）：抗菌肽（AMP）构成了先天免疫系统的第一道防线，并具有广泛的晶状体活性，可针对广泛的革兰氏阴性和革兰氏阴性细菌，真菌，原生物，原生物和革兰氏阴性细菌以及甚至包裹病毒。最近，由于它们在治疗疾病方面具有巨大潜力，由于抗菌素耐药性无法通过常规抗生素治愈，因此它们成为了越来越多的兴趣。放大器诱导膜损伤，这是靶细菌的致命事件，或与细菌细胞质区域的几个靶标结合。所有证据表明，由于AMP与目标的相互作用通常被认为是非特异性的，因此AMP的作用不涉及立体蛋白质受体识别。因此，AMP与细菌细胞壁脂质，病毒包膜或天然浆细胞膜脂质的相互作用的特征在很大程度上决定了其裂解电位。作为我们研究的一部分，将开发出新型的平面仿生膜，无论是在空气水和固液界面上。这将允许使用高度敏感的结构实验技术，该技术不能用囊泡系统或真实细胞使用。此外，除了AMP外，我们还计划研究其合成肽模拟物（两极体）的膜相互作用，它们具有抗蛋白酶的优势，同时表现出较高的效力和选择性为抗菌剂。在这项高度跨学科的建议中，我们计划使用尖端同步X射线散射技术，这些散射技术与AFM和落荧光研究一起将产生接近肽 - 脂质相互作用的原子分辨率。这些数据将用于促进对AMP和AMETOIDS作用模式的理解，这些模式可用于制定AMP和抗菌肽模拟物的合理设计策略，以提高高度有效的药物的开发，这些药物甚至有效地抗多药物抗性细菌和病毒。该项目的具体目的是：（1）使用X射线X-ray衍射，X-射线衍射，X-射线衍射率，检查代表红细胞膜的外部小叶和细菌细胞壁的表面层的脂质单层和脂质单层的相互作用模式。射线反射率，表现显微镜和以互补方式使用的AFM。 （2）在空气水界面设计新型的流体双层膜，使用它们来检查AMP和两极分子与双层膜的两个小叶的相互作用。 （3）设计具有细胞骨架成分的新型胆固醇双层脂质膜（TBLM）。检查AMP和Ampetoids与这些TBLM的相互作用的机理，并阐明细胞骨架在相互作用中的作用。拟议研究的更广泛的影响是推动新型抗生素和抗病毒药物的发展，这些抗生素和抗病毒药物将免疫细菌和病毒突变。抗菌素肽及其合成模拟物具有巨大的细菌耐药潜力，因为它们不仅与特定的膜蛋白受体相互作用，而且与细胞膜的脂质基质相互作用，其脂质组成极不可能随着细菌突变而变化。更好地了解分子水平上的抗菌肽和肽作用方式可以增强当今使用的常规抗生素和抗病毒药物的有效替代品的设计和开发。