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Ting DSJ, Goh ETL, Mayandi V, Busoy JMF, Aung TT, Periayah MH, Nubile M, Mastropasqua L, Said DG, Htoon HM, Barathi VA, Beuerman RW, Lakshminarayanan R, Mohammed I, Dua HS. Hybrid derivative of cathelicidin and human beta defensin-2 against Gram-positive bacteria: A novel approach for the treatment of bacterial keratitis. Sci Rep 2021; 11:18304. [PMID: 34526600 PMCID: PMC8443647 DOI: 10.1038/s41598-021-97821-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 08/24/2021] [Indexed: 02/06/2023] Open
Abstract
Bacterial keratitis (BK) is a major cause of corneal blindness globally. This study aimed to develop a novel class of antimicrobial therapy, based on human-derived hybrid host defense peptides (HyHDPs), for treating BK. HyHDPs were rationally designed through combination of functional amino acids in parent HDPs, including LL-37 and human beta-defensin (HBD)-1 to -3. Minimal inhibitory concentrations (MICs) and time-kill kinetics assay were performed to determine the concentration- and time-dependent antimicrobial activity and cytotoxicity was evaluated against human corneal epithelial cells and erythrocytes. In vivo safety and efficacy of the most promising peptide was examined in the corneal wound healing and Staphylococcus aureus (ATCC SA29213) keratitis murine models, respectively. A second-generation HyHDP (CaD23), based on rational hybridization of the middle residues of LL-37 and C-terminal of HBD-2, was developed and was shown to demonstrate good efficacy against methicillin-sensitive and methicillin-resistant S. aureus [MIC = 12.5-25.0 μg/ml (5.2-10.4 μM)] and S. epidermidis [MIC = 12.5 μg/ml (5.2 μM)], and moderate efficacy against P. aeruginosa [MIC = 25-50 μg/ml (10.4-20.8 μM)]. CaD23 (at 25 μg/ml or 2× MIC) killed all the bacteria within 30 min, which was 8 times faster than amikacin (25 μg/ml or 20× MIC). After 10 consecutive passages, S. aureus (ATCC SA29213) did not develop any antimicrobial resistance (AMR) against CaD23 whereas it developed significant AMR (i.e. a 32-fold increase in MIC) against amikacin, a commonly used treatment for BK. Pre-clinical murine studies showed that CaD23 (0.5 mg/ml) achieved a median reduction of S. aureus bioburden by 94% (or 1.2 log10 CFU/ml) while not impeding corneal epithelial wound healing. In conclusion, rational hybridization of human-derived HDPs has led to generation of a potentially efficacious and safe topical antimicrobial agent for treating Gram-positive BK, with no/minimal risk of developing AMR.
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Affiliation(s)
- Darren Shu Jeng Ting
- Academic Ophthalmology, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Ophthalmology, Queen's Medical Centre, Nottingham, UK
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | - Eunice Tze Leng Goh
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | - Venkatesh Mayandi
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | - Joanna M F Busoy
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | - Thet Tun Aung
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | | | - Mario Nubile
- Ophthalmic Clinic, University "G d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | | | - Dalia G Said
- Academic Ophthalmology, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Ophthalmology, Queen's Medical Centre, Nottingham, UK
| | - Hla M Htoon
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
| | | | - Roger W Beuerman
- Anti-Infectives Research Group, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, USA
| | | | - Imran Mohammed
- Academic Ophthalmology, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK
| | - Harminder S Dua
- Academic Ophthalmology, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK.
- Department of Ophthalmology, Queen's Medical Centre, Nottingham, UK.
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Shaheen N, Qureshi NA, Ashraf A, Hamid A, Iqbal A, Fatima H. In vitro anti-leishmanial activity of Prunus armeniaca fractions on Leishmania tropica and molecular docking studies. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 213:112077. [PMID: 33220600 DOI: 10.1016/j.jphotobiol.2020.112077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 10/08/2020] [Accepted: 10/30/2020] [Indexed: 11/25/2022]
Abstract
Prunus armeniaca (L.) is a member of the Rosaceae, subfamily Prunoideae, shows anticancer, antitubercular, antimutagenic, antimicrobial, antioxidant, and cardioprotective activities. Here we fractionated the leaves extract of this highly medicinally important plant for antileishmanial activity. In the current study, the leaves extract was fractionated and characterized using column and thin layer chromatography by n-hexane, ethyl acetate, and methanol solvents. Twelve fractions were isolated and subjected for evaluation of their cytotoxicity and in vitro antileishmanial activity against promastigotes and amastigotes of Leishmania tropica. Among all fractions used, the fraction (F7) exhibited the strongest antileishmanial activity. The bioactive fraction was further characterized by spectroscopy (FTIR, UV-Vis), and GC-MS analysis. The in silico docking was carried out to find the active site of PTR1. All derived fractions exhibited toxicity in the safety range IC50 > 100 μg/ml. The fraction (F7) showed significantly the highest antipromastigotes activity with IC5011.48 ± 0.82 μg/ml and antiamastigotes activity with IC50 21.03 ± 0.98 μg/ml compared with control i.e. 11.60 ± 0.70 and 22.03 ± 1.02 μg/ml respectively. The UV-Vis spectroscopic analysis revealed the presence of six absorption peaks and the FTIR spectrum revealed the presence of alkane, aldehyde, carboxylic acid, thiols, alkynes, and carbonyls compounds The GC-MS chromatogram exhibited the presence of nine compounds: (a) benzeneethanol, alpha, beta dimethyl, (b)carbazic acid, 3-(1 propylbutylidene)-, ethyl ester, (c)1, 2-benzenedicarboxylic acid, diisooctyl ester, (d)benzeneethanamine a-methyl, (e)2aminononadecane, (f)2-heptanamine-5-methyl, (g)cyclobutanol, (h)cyclopropyl carbine, and (i)nitric acid, nonyl ester. Among all compounds, the 1, 2-benzenedicarboxylic acid, diisooctyl ester bound well to the PTR1 receptor. Fraction (F7) showed acceptable results with no cytotoxicity. However, in vivo studies are required in the future.
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Affiliation(s)
- Nargis Shaheen
- Department of Zoology, Faculty of Biological Science, Quaid-i-Azam University Islamabad, 45320, Pakistan
| | - Naveeda Akhter Qureshi
- Department of Zoology, Faculty of Biological Science, Quaid-i-Azam University Islamabad, 45320, Pakistan.
| | - Asma Ashraf
- Department of Zoology, Faculty of Biological Science, Quaid-i-Azam University Islamabad, 45320, Pakistan
| | - Aneeqa Hamid
- Deparment of Pharmacy, Quaid-i-Azam University Islamabad, Pakistan
| | - Attiya Iqbal
- Department of Zoology, Faculty of Biological Science, Quaid-i-Azam University Islamabad, 45320, Pakistan
| | - Huma Fatima
- Department of Zoology, Faculty of Biological Science, Quaid-i-Azam University Islamabad, 45320, Pakistan
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3
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Domingues TM, Perez KR, Riske KA. Revealing the Mode of Action of Halictine Antimicrobial Peptides: A Comprehensive Study with Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:5145-5155. [PMID: 32336099 DOI: 10.1021/acs.langmuir.0c00282] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Antimicrobial peptides are innate host defense molecules with the ability to kill pathogens. They have been widely studied for their membrane lytic activity and their potential to overcome the ever-increasing threat of antimicrobial resistance against conventional antibiotics. Here, we focus on two halictines, antimicrobial peptides first obtained from the venom of the eusocial bee Halictus sexcinctus. The peptides, HAL-1 and HAL-2, are cationic (with +3 and +4 charges, respectively) and amphipathic, have 12 amino acid residues, and exhibit high biological activity. For this study, the mechanism of action of HAL-1 and HAL-2 was studied in detail using large and giant unilamellar vesicles composed of pure palmitoyl oleoyl phosphatidyl choline (POPC) and a mixture of POPC and the anionic lipid palmitoyl oleoyl phosphatidyl glycerol (POPG) as biomimetic models of the membranes of eukaryotes and microorganisms, respectively. A set of complementary techniques was put forward: carboxyfluorescein leakage assay, phase contrast optical microscopy, ζ-potential, static and dynamic light scattering, fluorescence and circular dichroism spectroscopies, and isothermal titration calorimetry. The results show that both halictines are able to interact strongly with anionic membranes: The interaction is exothermic and accompanied by structuring of the peptides as an α-helix and deep insertion into the membrane causing substantial membrane permeabilization at very low peptide/lipid molar ratios. Extensive vesicle aggregation was detected only at a high peptide concentration. On the other hand, the interaction of the halictines with POPC is significantly milder. Yet, the peptides were able to permeabilize the POPC membranes to some extent. Comparing both peptides, HAL-1 showed a somewhat stronger effect on model membranes. Fits to the data revealed apparent binding constants on the order of 103-104 M-1 for anionic membranes and 1 order of magnitude lower for zwitterionic bilayers. When lytic activity results were compared at the same bound peptide/lipid ratio, the halictines exhibited a higher activity toward zwitterionic membranes. As novel peptides, small and with powerful activity, these halictines are potential candidates for becoming antimicrobial agents.
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Affiliation(s)
- Tatiana M Domingues
- Departamento de Biofı́sica, Universidade Federal de São Paulo, São Paulo 04021-001, Brazil
| | - Katia R Perez
- Departamento de Biofı́sica, Universidade Federal de São Paulo, São Paulo 04021-001, Brazil
| | - Karin A Riske
- Departamento de Biofı́sica, Universidade Federal de São Paulo, São Paulo 04021-001, Brazil
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Almeida MM, Perez KR, Faig A, Uhrich KE, Riske KA. Location of the Positive Charges in Cationic Amphiphiles Modulates Their Mechanism of Action against Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14117-14123. [PMID: 31589461 DOI: 10.1021/acs.langmuir.9b02606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Synthetic cationic amphiphiles (CAms) with physicochemical properties similar to antimicrobial peptides are promising molecules in the search for alternative antibiotics to which pathogens cannot easily develop resistance. Here, we investigate two types of CAms based on tartaric acid and containing two hydrophobic chains (of 7 or 11 carbons) and two positive charges, located either at the end of the acyl chains (bola-like, B7 and B11) or at the tartaric acid backbone (gemini-like, G7 and G11). The interaction of the CAms with biomimetic membrane models (anionic and neutral liposomes) was studied with zeta potential and dynamic light scattering measurements, isothermal titration calorimetry, and a fluorescent-based leakage assay. We show that the type of molecule determines the mechanism of action of the CAms. Gemini-like molecules (G7 and G11) interact mainly via electrostatics (exothermic process) and reside in the external vesicle leaflet, altering substantially the vesicle surface potential but not causing significant membrane lysis. On the other hand, the interaction of bola-like CAms (B7 and B11) is endothermic and thus entropy-driven, and these molecules reach both membrane leaflets and cause substantial membrane permeabilization, likely after clustering of anionic lipids. The lytic ability is clearly higher against anionic membranes as compared with neutral membranes. Within each class of molecule, longer alkyl chains (i.e., B11 and G11) exhibit higher affinity and lytic ability. Overall, the molecule B11 exhibits a high potential as antimicrobial agent, since it has a high membrane affinity and causes substantial membrane permeabilization.
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Affiliation(s)
- Marcio M Almeida
- Departament of Biophysics , Universidade Federal de São Paulo , São Paulo , Brazil
| | - Katia R Perez
- Departament of Biophysics , Universidade Federal de São Paulo , São Paulo , Brazil
| | - Allison Faig
- Department of Chemistry and Chemical Biology , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Kathryn E Uhrich
- Department of Chemistry and Chemical Biology , Rutgers University , Piscataway , New Jersey 08854 , United States
- Department of Chemistry , University of California, Riverside , Riverside , California 92521 , United States
| | - Karin A Riske
- Departament of Biophysics , Universidade Federal de São Paulo , São Paulo , Brazil
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Gan W, Schneidman D, Zhang N, Ma B, Nussinov R. Probing Oligomerized Conformations of Defensin in the Membrane. Methods Mol Biol 2017; 1529:353-362. [PMID: 27914061 PMCID: PMC6484831 DOI: 10.1007/978-1-4939-6637-0_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Computational prediction and design of membrane protein-protein interactions facilitate biomedical engineering and biotechnological applications. Due to their antimicrobial activity, human defensins play an important role in the innate immune system. Human defensins are attractive pharmaceutical targets due to their small size, broad activity spectrum, reduced immunogenicity, and resistance to proteolysis. Protein engineering based modification of defensins can improve their pharmaceutical properties. Here we present an approach to computationally probe defensins' oligomerization states in the membrane. First, we develop a novel docking and rescoring algorithm. Then, on the basis of the 3D structure of Sapecin, an insect defensin, and a model of its antimicrobial ion-channel, we optimize the parameters of our empirical scoring function. Finally, we apply our docking program and scoring function to the hBD-2 (human β-defensin-2) molecule and obtain structures of four possible oligomers. These results can be used in higher level simulations.
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Affiliation(s)
- Wenxun Gan
- Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300060, China
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin, 300060, China
| | - Dina Schneidman
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, 94158, USA
| | - Ning Zhang
- Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300060, China
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin, 300060, China
| | - Buyong Ma
- Basic Science Program, Leidos Biomedical Research, Inc., Frederick, MD, 21702, USA
- Cancer and Inflammation Program, National Cancer Institute, Frederick, MD, 21702, USA
| | - Ruth Nussinov
- Basic Science Program, Leidos Biomedical Research, Inc., Frederick, MD, 21702, USA.
- Cancer and Inflammation Program, National Cancer Institute, Frederick, MD, 21702, USA.
- Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Sackler Institute of Molecular Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
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Sugano M, Morisaki H, Negishi Y, Endo-Takahashi Y, Kuwata H, Miyazaki T, Yamamoto M. Potential effect of cationic liposomes on interactions with oral bacterial cells and biofilms. J Liposome Res 2015; 26:156-62. [PMID: 26152278 DOI: 10.3109/08982104.2015.1063648] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
CONTEXT Although oral infectious diseases have been attributed to bacteria, drug treatments remain ineffective because bacteria and their products exist as biofilms. Cationic liposomes have been suggested to electrostatically interact with the negative charge on the bacterial surface, thereby improving the effects of conventional drug therapies. However, the electrostatic interaction between oral bacteria and cationic liposomes has not yet been examined in detail. OBJECTIVE The aim of the present study was to examine the behavior of cationic liposomes and Streptococcus mutans in planktonic cells and biofilms. MATERIALS AND METHODS Liposomes with or without cationic lipid were prepared using a reverse-phase evaporation method. The zeta potentials of conventional liposomes (without cationic lipid) and cationic liposomes were -13 and 8 mV, respectively, and both had a mean particle size of approximately 180 nm. We first assessed the interaction between liposomes and planktonic bacterial cells with a flow cytometer. We then used a surface plasmon resonance method to examine the binding of liposomes to biofilms. We confirmed the binding behavior of liposomes with biofilms using confocal laser scanning microscopy. RESULTS The interactions between cationic liposomes and S. mutans cells and biofilms were stronger than those of conventional liposomes. Microscopic observations revealed that many cationic liposomes interacted with the bacterial mass and penetrated the deep layers of biofilms. DISCUSSION AND CONCLUSION In this study, we demonstrated that cationic liposomes had higher affinity not only to oral bacterial cells, but also biofilms than conventional liposomes. This electrostatic interaction may be useful as a potential drug delivery system to biofilms.
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Affiliation(s)
- Marika Sugano
- a Division of Biomaterials & Engineering , Department of Conservative Dentistry, Showa University School of Dentistry , Shinagawa-ku, Tokyo , Japan .,b Department of Periodontology , Showa University School of Dentistry , Ohta-ku, Tokyo , Japan .,c Japan Society for the Promotion of Science (JSPS) , Chiyoda-ku, Tokyo , Japan
| | - Hirobumi Morisaki
- d Department of Oral Microbiology , Showa University School of Dentistry , Shinagawa-ku, Tokyo , Japan , and
| | - Yoichi Negishi
- e Department of Drug Delivery and Molecular Biopharmaceutics , School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Hachioji , Tokyo , Japan
| | - Yoko Endo-Takahashi
- e Department of Drug Delivery and Molecular Biopharmaceutics , School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Hachioji , Tokyo , Japan
| | - Hirotaka Kuwata
- d Department of Oral Microbiology , Showa University School of Dentistry , Shinagawa-ku, Tokyo , Japan , and
| | - Takashi Miyazaki
- a Division of Biomaterials & Engineering , Department of Conservative Dentistry, Showa University School of Dentistry , Shinagawa-ku, Tokyo , Japan
| | - Matsuo Yamamoto
- b Department of Periodontology , Showa University School of Dentistry , Ohta-ku, Tokyo , Japan
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7
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Wang XF, Tian F, Cao RM, Li J, Wu SM, Guo XK, Chen TX. Antimicrobial activity of human β-defensins against lactic acid bacteria. Nat Prod Res 2015; 29:2164-6. [DOI: 10.1080/14786419.2014.996754] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Optical Microscopy of Giant Vesicles as a Tool to Reveal the Mechanism of Action of Antimicrobial Peptides and the Specific Case of Gomesin. ADVANCES IN PLANAR LIPID BILAYERS AND LIPOSOMES 2015. [DOI: 10.1016/bs.adplan.2014.12.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Krishnakumari V, Packiyanathan KK, Nagaraj R. Human-β-defensins-1-3 and analogs do not require proton motive force for antibacterial activity against Escherichia coli. FEMS Microbiol Lett 2013; 348:52-7. [PMID: 23980689 DOI: 10.1111/1574-6968.12242] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 01/06/2023] Open
Abstract
Human-β-defensins 1-3 (HBD-1-3) and their C-terminal analogs Phd-1-3 do not show antibacterial activity against Escherichia coli in the presence of mono- and divalent cations. Activity of peptides was examined against E. coli pretreated with carbonyl cyanide m-chlorophenylhydrazone (CCCP) and salt remedial Escherichia coli ftsEX, a deletion mutant of FtsEX complex [an ATP-binding cassette (ABC) transporter protein], in the presence of Na(+), Ca(2+), and Mg(2+). Activity was observed in the presence of Na(+) and Ca(2+), although not in the presence of Mg(2+) against E. coli, when proton motive force (PMF) was dissipated by CCCP. The peptides exhibited antibacterial activity against E. coli ftsEX even in the presence of Na(+) and Ca(2+). Our results indicate that HBD-1-3 and Phd-1-3 do not require PMF for their antibacterial activity. The absence of activity against E. coli in the presence of Na(+) and Ca(2+) ions is due to not only weakened electrostatic interactions with anionic membrane components, but also involvement of electrochemical gradients. However, Mg(2+) prevents electrostatic interaction of the peptides with the outer membrane resulting in loss of activity.
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Cho H, Wu M, Bilgin B, Walton SP, Chan C. Latest developments in experimental and computational approaches to characterize protein-lipid interactions. Proteomics 2013; 12:3273-85. [PMID: 22997137 DOI: 10.1002/pmic.201200255] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Revised: 08/30/2012] [Accepted: 09/05/2012] [Indexed: 12/16/2022]
Abstract
Understanding the functional roles of all the molecules in cells is an ultimate goal of modern biology. An important facet is to understand the functional contributions from intermolecular interactions, both within a class of molecules (e.g. protein-protein) or between classes (e.g. protein-DNA). While the technologies for analyzing protein-protein and protein-DNA interactions are well established, the field of protein-lipid interactions is still relatively nascent. Here, we review the current status of the experimental and computational approaches for detecting and analyzing protein-lipid interactions. Experimental technologies fall into two principal categories, namely solution-based and array-based methods. Computational methods include large-scale data-driven analyses and predictions/dynamic simulations based on prior knowledge of experimentally identified interactions. Advances in the experimental technologies have led to improved computational analyses and vice versa, thereby furthering our understanding of protein-lipid interactions and their importance in biological systems.
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Affiliation(s)
- Hyunju Cho
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA
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