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Cecchet F. Light on the interactions between nanoparticles and lipid membranes by interface-sensitive vibrational spectroscopy. Colloids Surf B Biointerfaces 2024; 241:114013. [PMID: 38865867 DOI: 10.1016/j.colsurfb.2024.114013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/10/2024] [Accepted: 06/03/2024] [Indexed: 06/14/2024]
Abstract
Nanoparticles are produced in natural phenomena or synthesized artificially for technological applications. Their frequent contact with humans has been judged potentially harmful for health, and numerous studies are ongoing to understand the mechanisms of the toxicity of nanoparticles. At the macroscopic level, the toxicity can be established in vitro or in vivo by measuring the survival of cells. At the sub-microscopic level, scientists want to unveil the molecular mechanisms of the first interactions of nanoparticles with cells via the cell membrane, before the toxicity cascades within the whole cell. Unveiling a molecular understanding of the nanoparticle-membrane interface is a tricky challenge, because of the chemical complexity of this system and its nanosized dimensions buried within bulk macroscopic environments. In this review, we highlight how, in the last 10 years, second-order nonlinear optical (NLO) spectroscopy, and specifically vibrational sum frequency generation (SFG), has provided a new understanding of the structural, physicochemical, and dynamic properties of these biological interfaces, with molecular sensitivity. We will show how the intrinsic interfacial sensitivity of second-order NLO and the chemical information of vibrational SFG spectroscopy have revealed new knowledge of the molecular mechanisms that drive nanoparticles to interact with cell membranes, from both sides, the nanoparticles and the membrane properties.
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Affiliation(s)
- Francesca Cecchet
- Laboratory of Lasers and Spectroscopies (LLS), Namur Institute of Structured Matter (NISM) and NAmur Institute for Life Sciences (NARILIS), University of Namur (UNamur), Belgium.
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2
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Zhang H, Liu D, Zhang J, Adams E, Gong J, Li W, Wang B, Liu X, Yang R, Wei F, Allen HC. GMP affected assembly behaviors of phosphatidylethanolamine monolayers elucidated by multi-resolved SFG-VS and BAM. Colloids Surf B Biointerfaces 2024; 241:113995. [PMID: 38870647 DOI: 10.1016/j.colsurfb.2024.113995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/18/2024] [Accepted: 05/26/2024] [Indexed: 06/15/2024]
Abstract
The interaction between nucleotide molecules and lipid molecules plays important roles in cell activities, but the molecular mechanism is very elusive. In the present study, a small but noticeable interaction between the negatively charged phosphatidylethanolamine (PE) and Guanosine monophosphate (GMP) molecules was observed from the PE monolayer at the air/water interface. As shown by the sum frequency generation (SFG) spectra and Pi-A isotherm of the PE monolayer, the interaction between the PE and GMP molecules imposes very small changes to the PE molecules. However, the Brewster angle microscopy (BAM) technique revealed that the assembly conformations of PE molecules are significantly changed by the adsorption of GMP molecules. By comparing the SFG spectra of PE monolayers after the adsorption of GMP, guanosine and guanine, it is also shown that the hydrogen bonding effect plays an important role in the nucleotide-PE interactions. These results provide fundamental insight into the structure changes during the nucleotide-lipid interaction, which may shed light on the molecular mechanism of viral infection, DNA drug delivery, and cell membrane curvature control in the brain or neurons.
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Affiliation(s)
- Hongjuan Zhang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Dongqi Liu
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Jiawei Zhang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Ellen Adams
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | - Jingjing Gong
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Wenhui Li
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Bing Wang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Xueqing Liu
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Renqiang Yang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Feng Wei
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China.
| | - Heather C Allen
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA.
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Lee S, Kim HJ, Choi JH, Jang HJ, Cho HB, Kim HR, Park JI, Park KS, Park KH. Light emitting diode (LED) irradiation of liposomes enhances drug encapsulation and delivery for improved cancer eradication. J Control Release 2024; 368:756-767. [PMID: 38499090 DOI: 10.1016/j.jconrel.2024.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/26/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024]
Abstract
Liposomes are widely used as drug delivery nanoplatforms because of their versatility and biocompatibility; however, their ability to load certain drugs may be suboptimal. In this study, we generated liposomes using a combination of DSPE and DSPE-PEG-2 k lipids and loaded them with doxorubicin (DOX) and paclitaxel (PTX), to investigate the effects of light emitting diode (LED) irradiation on liposome structure and drug loading efficiency. Scanning and transmission electron microscopy revealed that the surface of liposomes irradiated with blue or near-infrared LEDs (LsLipo) was rougher and more irregular than that of non-LED-irradiated liposomes (NsLipo). Nuclear magnetic resonance analysis showed that the hydrogen peak originating from the lipid head groups was lower in LsLipo than in NsLipo preparations, indicating that LED irradiation changed the chemical and physical properties of the liposome. Structural changes, such as reduced rigidity, induced by LED irradiation, increased the loading efficiency of DOX and PTX. In vitro and in vivo experiments showed that LsLipo were more effective at inhibiting the growth of cancer cells than NsLipo. Our findings suggest that LED irradiation enhances the drug delivery efficacy of liposomes and offer new possibilities for improving drug delivery systems.
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Affiliation(s)
- Sujeong Lee
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea
| | - Hye Jin Kim
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea
| | - Jin-Ho Choi
- Department of Biomedical Science, CHA University, Seongnam, Republic of Korea
| | - Hye Jung Jang
- Department of Biomedical Science, CHA University, Seongnam, Republic of Korea
| | - Hui Bang Cho
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea
| | - Hye-Ryoung Kim
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea
| | - Ji-In Park
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea
| | - Kyung-Soon Park
- Department of Biomedical Science, CHA University, Seongnam, Republic of Korea.
| | - Keun-Hong Park
- Laboratory of Nano-regenerative Medicine, Department of Biomedical Science, College of Life Science, CHA University, CHA Biocomplex, Sampyeong-Dong, Bundang-gu, Seongnam-si 13488, Republic of Korea.
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Konishi R, Fukuda K, Kuriyama S, Masatani T, Xuan X, Fujita A. Unique asymmetric distribution of phosphatidylserine and phosphatidylethanolamine in Toxoplasma gondii revealed by nanoscale analysis. Histochem Cell Biol 2023; 160:279-291. [PMID: 37477836 DOI: 10.1007/s00418-023-02218-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2023] [Indexed: 07/22/2023]
Abstract
Toxoplasma gondii is a highly prevalent obligate apicomplexan parasite that is important in clinical and veterinary medicine. It is known that glycerophospholipids phosphatidylserine (PtdSer) and phosphatidylethanolamine (PtdEtn), especially their expression levels and flip-flops between cytoplasmic and exoplasmic leaflets, in the membrane of T. gondii play important roles in efficient growth in host mammalian cells, but their distributions have still not been determined because of technical difficulties in studying intracellular lipid distribution at the nanometer level. In this study, we developed an electron microscopy method that enabled us to determine the distributions of PtdSer and PtdEtn in individual leaflets of cellular membranes by using quick-freeze freeze-fracture replica labeling. Our findings show that PtdSer and PtdEtn are asymmetrically distributed, with substantial amounts localized at the luminal leaflet of the inner membrane complex (IMC), which comprises flattened vesicles located just underneath the plasma membrane (see Figs. 2B and 7). We also found that PtdSer was absent in the cytoplasmic leaflet of the inner IMC membrane, but was present in considerable amounts in the cytoplasmic leaflet of the middle IMC membrane, suggesting a barrier-like mechanism preventing the diffusion of PtdSer in the cytoplasmic leaflets of the two membranes. In addition, the expression levels of both PtdSer and PtdEtn in the luminal leaflet of the IMC membrane in the highly virulent RH strain were higher than those in the less virulent PLK strain. We also found that the amount of glycolipid GM3, a lipid raft component, was higher in the RH strain than in the PLK strain. These results suggest a correlation between lipid raft maintenance, virulence, and the expression levels of PtdSer and PtdEtn in T. gondii.
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Affiliation(s)
- Rikako Konishi
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima, 890-0065, Japan
| | - Kayoko Fukuda
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima, 890-0065, Japan
| | - Sayuri Kuriyama
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima, 890-0065, Japan
| | - Tatsunori Masatani
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
- Center for One Medicine Innovative Translational Research (COMIT), Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Xuenan Xuan
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, 080-8555, Japan
| | - Akikazu Fujita
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima, 890-0065, Japan.
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5
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Rozak H, Nihonyanagi S, Myalitsin A, Roy S, Ahmed M, Tahara T, Rzeznicka II. Adsorption of SARS-CoV-2 Spike (N501Y) RBD to Human Angiotensin-Converting Enzyme 2 at a Lipid/Water Interface. J Phys Chem B 2023; 127:4406-4414. [PMID: 37171105 DOI: 10.1021/acs.jpcb.3c00832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The receptor binding domain (RBD) of spike proteins plays a crucial role in the process of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) attachment to the human angiotensin-converting enzyme 2 (ACE2). The N501Y mutation and later mutations introduced extra positive charges on the spike RBD and resulted in higher transmissibility, likely due to stronger binding with the highly negatively charged ACE2. Consequently, many studies have been devoted to understanding the molecular mechanism of spike protein binding with the ACE2 receptor. Most of the theoretical studies, however, have been done on isolated proteins. ACE2 is a transmembrane protein; thus, it is important to understand the interaction of spike proteins with ACE2 in a lipid matrix. In this study, the adsorption of ACE2 and spike (N501Y) RBD at a lipid/water interface was studied using the heterodyne-detected vibrational sum frequency generation (HD-VSFG) technique. The technique is a non-linear optical spectroscopy which measures vibrational spectra of molecules at an interface and provides information on their structure and orientation. It is found that ACE2 is effectively adsorbed at the positively charged 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP) lipid monolayer via electrostatic interactions. The adsorption of ACE2 at the DPTAP monolayer causes a reorganization of interfacial water (D2O) from the D-down to the D-up orientation, indicating that the originally positively charged DPTAP interface becomes negatively charged due to ACE2 adsorption. The negatively charged interface (DPTAP/ACE2) allows further adsorption of positively charged spike RBD. HD-VSFG spectra in the amide I region show differences for spike (N501Y) RBD adsorbed at D2O, DPTAP, and DPTAP/ACE2 interfaces. A red shift observed for the spectra of spike RBD/DPTAP suggests that spike RBD oligomers are formed upon contact with DPTAP lipids.
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Affiliation(s)
- Harison Rozak
- College of Engineering, Shibaura Institute of Technology, Saitama City, Saitama 337-8570, Japan
| | - Satoshi Nihonyanagi
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Ultrafast Spectroscopy Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Anton Myalitsin
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- ANVOS Analytics Co., 4-168 Motomachi, Naka-ku, Yokohama, Kanagawa 231-0861, Japan
| | - Subhadip Roy
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mohammed Ahmed
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Ultrafast Spectroscopy Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tahei Tahara
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Ultrafast Spectroscopy Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Izabela I Rzeznicka
- College of Engineering, Shibaura Institute of Technology, Saitama City, Saitama 337-8570, Japan
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6
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Functional Analysis of the P-Type ATPases Apt2-4 from Cryptococcus neoformans by Heterologous Expression in Saccharomyces cerevisiae. J Fungi (Basel) 2023; 9:jof9020202. [PMID: 36836316 PMCID: PMC9966271 DOI: 10.3390/jof9020202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 02/09/2023] Open
Abstract
Lipid flippases of the P4-ATPase family actively transport phospholipids across cell membranes, an activity essential for key cellular processes such as vesicle budding and membrane trafficking. Members of this transporter family have also been implicated in the development of drug resistance in fungi. The encapsulated fungal pathogen Cryptococcus neoformans contains four P4-ATPases, among which Apt2-4p are poorly characterized. Using heterologous expression in the flippase-deficient S. cerevisiae strain dnf1Δdnf2Δdrs2Δ, we tested their lipid flippase activity in comparison to Apt1p using complementation tests and fluorescent lipid uptake assays. Apt2p and Apt3p required the co-expression of the C. neoformans Cdc50 protein for activity. Apt2p/Cdc50p displayed a narrow substrate specificity, limited to phosphatidylethanolamine and -choline. Despite its inability to transport fluorescent lipids, the Apt3p/Cdc50p complex still rescued the cold-sensitive phenotype of dnf1Δdnf2Δdrs2Δ, suggesting a functional role for the flippase in the secretory pathway. Apt4p, the closest homolog to Saccharomyces Neo1p, which does not require a Cdc50 protein, was unable to complement several flippase-deficient mutant phenotypes, neither in the presence nor absence of a β-subunit. These results identify C. neoformans Cdc50 as an essential subunit for Apt1-3p and provide a first insight into the molecular mechanisms underlying their physiological functions.
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Altman RM, Richmond GL. Twist and Stretch: Assignment and Surface Charge Sensitivity of a Water Combination Band and Its Implications for Vibrational Sum Frequency Spectra Interpretations. J Phys Chem B 2021; 125:6717-6726. [DOI: 10.1021/acs.jpcb.1c03408] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Rebecca M. Altman
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Geraldine L. Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
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8
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Windowless detection geometry for sum frequency scattering spectroscopy in the C-D and amide I regions. Biointerphases 2021; 16:011201. [PMID: 33706523 DOI: 10.1116/6.0000419] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Understanding the structure and chemistry of nanoscopic surfaces is an important challenge for biointerface sciences. Sum frequency scattering (SFS) spectroscopy can specifically probe the surfaces of nanoparticles, vesicles, liposomes, and other materials relevant to biomaterial research, and, as a vibrational spectroscopy method, it can provide molecular level information about the surface chemistry. SFS is particularly promising to probe the structure of proteins, and other biological molecules, at nanoparticle surfaces. Here, amide I spectra can provide information about protein folding and orientation, while spectra in the C-D and C-H stretching regions allow experiments to determine the mode of interaction between particle surfaces and proteins. Methods used currently employ a closed liquid cell or cuvette, which works extremely well for C-H and phosphate regions but is often impeded in the amide I and C-D regions by a strong background signal that originates from the window material of the sample cells. Here, we discuss a windowless geometry for collecting background-free and high-fidelity SFS spectra in the amide I and C-D regions. We demonstrate the improvement in spectra quality by comparing SFS spectra of unextruded, multilamellar vesicles in a sample cuvette with those recorded using the windowless geometry. The sample geometry we propose will enable new experiments using SFS as a probe for protein-particle interactions.
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Miasaki KMF, Wilke N, Neto JR, Alvares DS. N-terminal acetylation of a mastoparan-like peptide enhances PE/PG segregation in model membranes. Chem Phys Lipids 2020; 232:104975. [PMID: 32949566 DOI: 10.1016/j.chemphyslip.2020.104975] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 11/18/2022]
Abstract
The synthetic peptides L1A and its acetylated analog (acL1A) display potent Gram-negative bactericidal activities without being hemolytic. We have gathered evidence that the N-terminal acetylation of L1A enhances the lytic activity in anionic vesicles with high capability to insert into and disturb lipid packing of model membranes. Here, the impact of L1A and acL1A was evaluated on a model membrane that mimics the cytoplasmic membrane of Gram-negative bacteria, which is rich in phosphatidylethanolamine (PE) and phosphatidylglycerol (PG), using 3:1 mixture of POPE/DOPG and a variety of techniques. We followed peptide adsorption and penetration by zeta potential determination of large unilamellar vesicles, accessibility of tryptophan residue to acrylamide by quenching assays, and Gibbs isotherms. The secondary structure of the peptide on the membranes was assessed using circular dichroism. Peptide mixing ability with the lipids and phase segregation was assessed by the observation of Langmuir monolayers with fluorescence microscopy, as well as with differential scanning calorimetry thermograms of multilamellar vesicles. All in all, the results indicate that both peptides adsorb and penetrate POPE/DOPG membranes with similar affinities, decreasing the surface charge, and adopting alpha structures. Both peptides mix with DOPG and demix from POPE, and consequently, persist at the interface to larger surface pressures in the presence of PG than in pure PE monolayers. This selective degree of mixing of the peptides with PE and PG leads to peptide-induced segregation of PG from PE, being the less charged peptide, acL1A, able to segregate the lipids more efficiently.
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Affiliation(s)
- Kenneth M F Miasaki
- UNESP - São Paulo State University, IBILCE, Department of Physics, São José do Rio Preto, SP, Brazil
| | - Natalia Wilke
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, X5000HUA, Argentina
| | - João Ruggiero Neto
- UNESP - São Paulo State University, IBILCE, Department of Physics, São José do Rio Preto, SP, Brazil
| | - Dayane S Alvares
- UNESP - São Paulo State University, IBILCE, Department of Physics, São José do Rio Preto, SP, Brazil.
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10
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Hosseinpour S, Roeters SJ, Bonn M, Peukert W, Woutersen S, Weidner T. Structure and Dynamics of Interfacial Peptides and Proteins from Vibrational Sum-Frequency Generation Spectroscopy. Chem Rev 2020; 120:3420-3465. [DOI: 10.1021/acs.chemrev.9b00410] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Saman Hosseinpour
- Institute of Particle Technology (LFG), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | | | - Mischa Bonn
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Wolfgang Peukert
- Institute of Particle Technology (LFG), Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Sander Woutersen
- Van’t Hoff Institute for Molecular Sciences, University of Amsterdam, 1098 EP Amsterdam, The Netherlands
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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11
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Liu Z, Barber C, Gupta A, Wan L, Won YW, Furenlid LR, Chen Q, Desai AA, Zhao M, Bull DA, Unger EC, Martin DR. Imaging assessment of cardioprotection mediated by a dodecafluoropentane oxygen-carrier administered during myocardial infarction. Nucl Med Biol 2019; 70:67-77. [PMID: 30772168 DOI: 10.1016/j.nucmedbio.2019.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/18/2018] [Accepted: 01/14/2019] [Indexed: 01/25/2023]
Abstract
INTRODUCTION The objective of this study was to investigate the cardioprotective effects of a dodecafluoropentane (DDFP)-based perfluorocarbon emulsion (DDFPe) as an artificial carrier for oxygen delivery to ischemic myocardium, using 99mTc-duramycin SPECT imaging. METHODS Rat hearts with Ischemia-reperfusion (I/R) was prepared by coronary ligation for 45-min followed by reperfusion. The feasibility of 99mTc-duramycin in detecting myocardial I/R injury and its kinetic profile were first verified in the ischemic hearts with 2-h reperfusion (n = 6). DDFPe (0.6 mL/kg) was intravenously administered at 10 min after coronary ligation in fifteen rats and saline was given in thirteen rats as controls. 99mTc-duramycin SPECT images were acquired in the DDFPe-treated hearts and saline controls at 2-h (DDFPe-2 h, n = 7 and Saline-2 h, n = 6) or 24-h (DDFPe-24 h, n = 8 and Saline-24 h, n = 7) of reperfusion. RESULTS SPECT images, showing "hot-spot" 99mTc-duramycin uptake in the ischemic myocardium, exhibited significantly lower radioactive retention and smaller hot-spot size in the DDFPe-2 h and DDFPe-24 h hearts compared to controls. The infarcts in the Saline-24 h hearts extended significantly relative to measurements in the Saline-2 h. The extension of infarct size did not reach a statistical difference between the DDFPe-2 h and DDFPe-24 h hearts. Ex vivo measurement of 99mTc-duramycin activity (%ID/g) was lower in the ischemic area of DDFPe-2 h and DDFPe-24 h than that of the Saline-2 h and Saline-24 h hearts (P < 0.05). The area of injured myocardium, delineated by the uptake of 99mTc-duramycin, extended more substantially outside the infarct zone in the controls. CONCLUSIONS Significant reduction in myocardial I/R injury, as assessed by 99mTc-duramycin cell death imaging and histopathological analysis, was induced by DDFPe treatment after acute myocardial ischemia. 99mTc-duramycin imaging can reveal myocardial cell death in ischemic hearts and may provide a tool for the non-invasive assessment of cardioprotective interventions.
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Affiliation(s)
- Zhonglin Liu
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America.
| | - Christy Barber
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Akash Gupta
- Division of Cardiology of Department of Medicine, University of Arizona, Tucson, AZ, United States of America
| | - Li Wan
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Young-Wook Won
- Division of Cardiothoracic Surgery of Department of Surgery, University of Arizona, Tucson, AZ, United States of America
| | - Lars R Furenlid
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Qin Chen
- Department of Pharmacology, University of Arizona, Tucson, AZ, United States of America
| | - Ankit A Desai
- Division of Cardiology of Department of Medicine, University of Arizona, Tucson, AZ, United States of America
| | - Ming Zhao
- Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America
| | - David A Bull
- Division of Cardiothoracic Surgery of Department of Surgery, University of Arizona, Tucson, AZ, United States of America
| | - Evan C Unger
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America; NuvOx Pharma, LLC., Tucson, AZ, United States of America
| | - Diego R Martin
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America.
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12
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Lopatniuk M, Myronovskyi M, Luzhetskyy A. Streptomyces albus: A New Cell Factory for Non-Canonical Amino Acids Incorporation into Ribosomally Synthesized Natural Products. ACS Chem Biol 2017; 12:2362-2370. [PMID: 28758722 DOI: 10.1021/acschembio.7b00359] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The incorporation of noncanonical amino acids (ncAAs) with different side chains into a peptide is a promising technique for changing the functional properties of that peptide. Of particular interest is the incorporation of ncAAs into peptide-derived natural products to optimize their biophysical properties for medical and industrial applications. Here, we present the first instance of ncAA incorporation into the natural product cinnamycin in streptomycetes using the orthogonal pyrrolysyl-tRNA synthetase/tRNAPyl pair from Methanosarcina barkeri. This approach allows site-specific incorporation of ncAAs via the read-through of a stop codon by the suppressor tRNAPyl, which can carry different pyrrolysine analogues. Five new deoxycinnamycin derivatives were obtained with three distinct pyrrolysine analogues incorporated into diverse positions of the antibiotic. The combination of partial hydrolysis and MS/MS fragmentation analysis was used to verify the exact position of the incorporation events. The introduction of ncAAs into different positions of the peptide had opposite effects on the peptide's biological activity.
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Affiliation(s)
- Mariia Lopatniuk
- Department
of Pharmaceutical Biotechnology, Saarland University, 66123 Saarbrücken, Germany
| | - Maksym Myronovskyi
- Department
of Pharmaceutical Biotechnology, Saarland University, 66123 Saarbrücken, Germany
| | - Andriy Luzhetskyy
- Department
of Pharmaceutical Biotechnology, Saarland University, 66123 Saarbrücken, Germany
- Helmholtz-Institute for Pharmaceutical Research, Saarland Campus, Building C2.3, 66123 Saarbrücken, Germany
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13
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Phosphatidylethanolamine targeting for cell death imaging in early treatment response evaluation and disease diagnosis. Apoptosis 2017. [DOI: 10.1007/s10495-017-1384-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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14
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Bilkova E, Pleskot R, Rissanen S, Sun S, Czogalla A, Cwiklik L, Róg T, Vattulainen I, Cremer PS, Jungwirth P, Coskun Ü. Calcium Directly Regulates Phosphatidylinositol 4,5-Bisphosphate Headgroup Conformation and Recognition. J Am Chem Soc 2017; 139:4019-4024. [PMID: 28177616 PMCID: PMC5364432 DOI: 10.1021/jacs.6b11760] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The orchestrated recognition of phosphoinositides and concomitant intracellular release of Ca2+ is pivotal to almost every aspect of cellular processes, including membrane homeostasis, cell division and growth, vesicle trafficking, as well as secretion. Although Ca2+ is known to directly impact phosphoinositide clustering, little is known about the molecular basis for this or its significance in cellular signaling. Here, we study the direct interaction of Ca2+ with phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), the main lipid marker of the plasma membrane. Electrokinetic potential measurements of PI(4,5)P2 containing liposomes reveal that Ca2+ as well as Mg2+ reduce the zeta potential of liposomes to nearly background levels of pure phosphatidylcholine membranes. Strikingly, lipid recognition by the default PI(4,5)P2 lipid sensor, phospholipase C delta 1 pleckstrin homology domain (PLC δ1-PH), is completely inhibited in the presence of Ca2+, while Mg2+ has no effect with 100 nm liposomes and modest effect with giant unilamellar vesicles. Consistent with biochemical data, vibrational sum frequency spectroscopy and atomistic molecular dynamics simulations reveal how Ca2+ binding to the PI(4,5)P2 headgroup and carbonyl regions leads to confined lipid headgroup tilting and conformational rearrangements. We rationalize these findings by the ability of calcium to block a highly specific interaction between PLC δ1-PH and PI(4,5)P2, encoded within the conformational properties of the lipid itself. Our studies demonstrate the possibility that switchable phosphoinositide conformational states can serve as lipid recognition and controlled cell signaling mechanisms.
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Affiliation(s)
- Eva Bilkova
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,German Center for Diabetes Research (DZD e.V.) , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Roman Pleskot
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,Institute of Experimental Botany, Academy of Sciences of the Czech Republic , v.v.i., Rozvojová 263, 16502 Prague 6, Czech Republic
| | - Sami Rissanen
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland
| | | | - Aleksander Czogalla
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,Laboratory of Cytobiochemistry, Faculty of Biotechnology, University of Wrocław , Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Lukasz Cwiklik
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic , v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Tomasz Róg
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland.,Department of Physics, University of Helsinki , P.O. Box 64, FI-00014, Helsinki, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland.,Department of Physics, University of Helsinki , P.O. Box 64, FI-00014, Helsinki, Finland.,MEMPHYS- Center for Biomembrane Physics, University of Southern Denmark , DK-5230 Odense, Denmark
| | | | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland
| | - Ünal Coskun
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,German Center for Diabetes Research (DZD e.V.) , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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15
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Elvas F, Boddaert J, Vangestel C, Pak K, Gray B, Kumar-Singh S, Staelens S, Stroobants S, Wyffels L. 99mTc-Duramycin SPECT Imaging of Early Tumor Response to Targeted Therapy: A Comparison with 18F-FDG PET. J Nucl Med 2016; 58:665-670. [DOI: 10.2967/jnumed.116.182014] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/09/2016] [Indexed: 11/16/2022] Open
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16
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Probing phosphoethanolamine-containing lipids in membranes with duramycin/cinnamycin and aegerolysin proteins. Biochimie 2016; 130:81-90. [DOI: 10.1016/j.biochi.2016.09.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 09/27/2016] [Indexed: 02/07/2023]
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17
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Abstract
Duramycin, through binding with phosphatidylethanolamine (PE), has shown potential to be an effective antitumour agent. However, its mode of action in relation to tumour cells is not fully understood. PE expression on the surface of a panel of cancer cell lines was analysed using duramycin and subsequent antibody labelling, and then analysed by flow cytometry. Cell viability was also assessed by flow cytometry using annexin V and propidium iodide. Calcium ion (Ca) release by tumour cells in response to duramycin was determined by spectrofluorometry following incubation with Fluo-3, AM. Confocal microscopy was performed on the cancer cell line AsPC-1 to assess real-time cell response to duramycin treatment. Duramycin could detect cell surface PE expression on all 15 cancer cell lines screened, which was shown to be duramycin concentration dependent. However, higher concentrations induced necrotic cell death. Duramycin induced calcium ion (Ca) release from the cancer cell lines also in a concentration-dependent and time-dependent manner. Confocal microscopy showed an influx of propidium iodide into the cells over time and induced morphological changes. Duramycin induces Ca release from cancer cell lines in a time-dependent and concentration-dependent manner.
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18
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Liu Z, Larsen BT, Lerman LO, Gray BD, Barber C, Hedayat AF, Zhao M, Furenlid LR, Pak KY, Woolfenden JM. Detection of atherosclerotic plaques in ApoE-deficient mice using (99m)Tc-duramycin. Nucl Med Biol 2016; 43:496-505. [PMID: 27236285 DOI: 10.1016/j.nucmedbio.2016.05.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/07/2016] [Accepted: 05/11/2016] [Indexed: 12/25/2022]
Abstract
UNLABELLED Apoptosis of macrophages and smooth muscle cells is linked to atherosclerotic plaque destabilization. The apoptotic cascade leads to exposure of phosphatidylethanolamine (PE) on the outer leaflet of the cell membrane, thereby making apoptosis detectable using probes targeting PE. The objective of this study was to exploit capabilities of a PE-specific imaging probe, (99m)Tc-duramycin, in localizing atherosclerotic plaque and assessing plaque evolution in apolipoprotein-E knockout (ApoE(-/-)) mice. METHODS Atherosclerosis was induced in ApoE(-/-) mice by feeding an atherogenic diet. (99m)Tc-duramycin images were acquired using a small-animal SPECT imager. Six ApoE(-/-) mice at 20weeks of age (Group I) were imaged and then sacrificed for ex vivo analyses. Six additional ApoE(-/-) mice (Group II) were imaged at 20 and 40weeks of age before sacrifice. Six ApoE wild-type (ApoE(+/+)) mice (Group III) were imaged at 40weeks as controls. Five additional ApoE(-/-) mice (40weeks of age) (Group IV) were imaged with a (99m)Tc-labeled inactive peptide, (99m)Tc-LinDUR, to assess (99m)Tc-duramycin targeting specificity. RESULTS Focal (99m)Tc-duramycin uptake in the ascending aorta and aortic arch was detected at 20 and 40weeks in the ApoE(-/-) mice but not in ApoE(+/+) mice. (99m)Tc-duramycin uptake in the aortic lesions increased 2.2-fold on quantitative imaging in the ApoE(-/-) mice between 20 and 40weeks. Autoradiographic and histological data indicated significantly increased (99m)Tc-duramycin uptake in the ascending aorta and aortic arch associated with advanced plaques. Quantitative autoradiography showed that the ratio of activity in the aortic arch to descending thoracic aorta, which had no plaques or radioactive uptake, was 2.1 times higher at 40weeks than at 20weeks (6.62±0.89 vs. 3.18±0.29, P<0.01). There was barely detectable focal uptake of (99m)Tc-duramycin in the aortic arch of ApoE(+/+) mice. No detectable (99m)Tc-LinDUR uptake was observed in the aortas of ApoE(-/-) mice. CONCLUSIONS PE-targeting properties of (99m)Tc-duramycin in the atherosclerotic mouse aortas were noninvasively characterized. (99m)Tc-duramycin is promising in localizing advanced atherosclerotic plaques.
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Affiliation(s)
- Zhonglin Liu
- Department of Medical Imaging, University of Arizona, Tucson, AZ, USA.
| | | | - Lilach O Lerman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Brian D Gray
- Molecular Targeting Technologies, Inc, West Chester, PA, USA
| | - Christy Barber
- Department of Medical Imaging, University of Arizona, Tucson, AZ, USA
| | - Ahmad F Hedayat
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA
| | - Ming Zhao
- Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Lars R Furenlid
- Department of Medical Imaging, University of Arizona, Tucson, AZ, USA
| | - Koon Y Pak
- Molecular Targeting Technologies, Inc, West Chester, PA, USA
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19
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Dickinson SE, Janda J, Criswell J, Blohm-Mangone K, Olson ER, Liu Z, Barber C, Petricoin EF, Calvert VS, Einspahr J, Dickinson JE, Stratton SP, Curiel-Lewandrowski C, Saboda K, Hu C, Bode AM, Dong Z, Alberts DS, Timothy Bowden G. Inhibition of Akt Enhances the Chemopreventive Effects of Topical Rapamycin in Mouse Skin. Cancer Prev Res (Phila) 2016; 9:215-24. [PMID: 26801880 DOI: 10.1158/1940-6207.capr-15-0419] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 01/01/2016] [Indexed: 11/16/2022]
Abstract
The PI3Kinase/Akt/mTOR pathway has important roles in cancer development for multiple tumor types, including UV-induced nonmelanoma skin cancer. Immunosuppressed populations are at increased risk of aggressive cutaneous squamous cell carcinoma (SCC). Individuals who are treated with rapamycin (sirolimus, a classical mTOR inhibitor) have significantly decreased rates of developing new cutaneous SCCs compared with those that receive traditional immunosuppression. However, systemic rapamycin use can lead to significant adverse events. Here, we explored the use of topical rapamycin as a chemopreventive agent in the context of solar-simulated light (SSL)-induced skin carcinogenesis. In SKH-1 mice, topical rapamycin treatment decreased tumor yields when applied after completion of 15 weeks of SSL exposure compared with controls. However, applying rapamycin during SSL exposure for 15 weeks, and continuing for 10 weeks after UV treatment, increased tumor yields. We also examined whether a combinatorial approach might result in more significant tumor suppression by rapamycin. We validated that rapamycin causes increased Akt (S473) phosphorylation in the epidermis after SSL, and show for the first time that this dysregulation can be inhibited in vivo by a selective PDK1/Akt inhibitor, PHT-427. Combining rapamycin with PHT-427 on tumor prone skin additively caused a significant reduction of tumor multiplicity compared with vehicle controls. Our findings indicate that patients taking rapamycin should avoid sun exposure, and that combining topical mTOR inhibitors and Akt inhibitors may be a viable chemoprevention option for individuals at high risk for cutaneous SCC.
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Affiliation(s)
- Sally E Dickinson
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Pharmacology, The University of Arizona, Tucson, Arizona.
| | - Jaroslav Janda
- The University of Arizona Cancer Center, Tucson, Arizona
| | - Jane Criswell
- The University of Arizona Cancer Center, Tucson, Arizona
| | | | - Erik R Olson
- The University of Arizona Cancer Center, Tucson, Arizona
| | - Zhonglin Liu
- Department of Medical Imaging, The University of Arizona, Tucson, Arizona
| | - Christy Barber
- Department of Medical Imaging, The University of Arizona, Tucson, Arizona
| | - Emanuel F Petricoin
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia
| | - Valerie S Calvert
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia
| | - Janine Einspahr
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Medicine, The University of Arizona, Tucson, Arizona
| | - Jesse E Dickinson
- Arizona Water Science Center, U.S. Geological Survey, Tucson, Arizona
| | - Steven P Stratton
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Medicine, The University of Arizona, Tucson, Arizona
| | - Clara Curiel-Lewandrowski
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Medicine, The University of Arizona, Tucson, Arizona
| | | | - Chengcheng Hu
- The University of Arizona Cancer Center, Tucson, Arizona
| | - Ann M Bode
- Department of Molecular Medicine and Biopharmaceutical Sciences, The Hormel Institute, The University of Minnesota, Austin, Minnesota
| | - Zigang Dong
- Department of Molecular Medicine and Biopharmaceutical Sciences, The Hormel Institute, The University of Minnesota, Austin, Minnesota
| | - David S Alberts
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Medicine, The University of Arizona, Tucson, Arizona
| | - G Timothy Bowden
- The University of Arizona Cancer Center, Tucson, Arizona. Department of Medicine, The University of Arizona, Tucson, Arizona. Department of Cellular and Molecular Medicine, The University of Arizona, Tucson, Arizona
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20
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Phoenix DA, Harris F, Mura M, Dennison SR. The increasing role of phosphatidylethanolamine as a lipid receptor in the action of host defence peptides. Prog Lipid Res 2015; 59:26-37. [PMID: 25936689 DOI: 10.1016/j.plipres.2015.02.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 02/26/2015] [Accepted: 02/27/2015] [Indexed: 01/04/2023]
Abstract
Host defence peptides (HDPs) are antimicrobial agents produced by organisms across the prokaryotic and eukaryotic kingdoms. Many prokaryotes produce HDPs, which utilise lipid and protein receptors in the membranes of bacterial competitors to facilitate their antibacterial action and thereby survive in their niche environment. As a major example, it is well established that cinnamycin and duramycins from Streptomyces have a high affinity for phosphatidylethanolamine (PE) and exhibit activity against other Gram-positive organisms, such as Bacillus. In contrast, although eukaryotic HDPs utilise membrane interactive mechanisms to facilitate their antimicrobial activity, the prevailing view has long been that these mechanisms do not involve membrane receptors. However, this view has been recently challenged by reports that a number of eukaryotic HDPs such as plant cyclotides also use PE as a receptor to promote their antimicrobial activities. Here, we review current understanding of the mechanisms that underpin the use of PE as a receptor in the antimicrobial and other biological actions of HDPs and describe medical and biotechnical uses of these peptides, which range from tumour imaging and detection to inclusion in topical microbicidal gels to prevent the sexual transmission of HIV.
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Affiliation(s)
- David A Phoenix
- School of Applied Science, London South Bank University, 103 Borough Road, London SE1 0AA, UK.
| | - Frederick Harris
- School of Applied Science, London South Bank University, 103 Borough Road, London SE1 0AA, UK; School of Forensic and Investigative Science, University of Central Lancashire, Preston PR1 2HE, UK
| | - Manuela Mura
- School of Mathematics and Physics, College of Science, University of Lincoln, Brayford Pool, Lincoln, Lincolnshire LN6 7TS, UK
| | - Sarah R Dennison
- School of Applied Science, London South Bank University, 103 Borough Road, London SE1 0AA, UK; School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, UK
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21
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Okuno M, Mezger M, Stangenberg R, Baumgarten M, Müllen K, Bonn M, Backus EHG. Interaction of a patterned amphiphilic polyphenylene dendrimer with a lipid monolayer: electrostatic interactions dominate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:1980-1987. [PMID: 25602738 DOI: 10.1021/la504252s] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Dendrimeric macromolecules with defined shape and size are promising candidates for delivering drug or DNA molecules into cells. In this work we study the influence of an amphiphilic polyphenylene dendrimer on a model cell membrane consisting of a condensed 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid monolayer. A small surface pressure decrease is observed when the dendrimer solution is injected into the aqueous phase below the monolayer. X-ray reflectivity measurements show that the surface monolayer remains intact. The molecular-scale picture is obtained with sum-frequency generation spectroscopy. With this technique, we observe that the tails of the surfactant molecules become less ordered upon interaction with the amphiphilic polyphenylene dendrimer. In contrast, the water molecules below the DPPC layer become more ordered. Our observations suggest that electrostatic interactions between the negative charge of the dendrimer and the positively charged part of the DPPC headgroup keep the dendrimer located below the headgroup. No evidence of dendrimer insertion into the membrane has been observed. Apparently before entering the cell membrane the dendrimer can stick at the hydrophilic part of the lipids.
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Affiliation(s)
- Masanari Okuno
- Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany
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22
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Wei F, Xiong W, Li W, Lu W, Allen HC, Zheng W. Assembly and relaxation behaviours of phosphatidylethanolamine monolayers investigated by polarization and frequency resolved SFG-VS. Phys Chem Chem Phys 2015; 17:25114-22. [DOI: 10.1039/c5cp03977k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polarization and frequency resolved SFG-VS to distinguish the head/tail groups of lipids, to resolve the assembly and relaxation kinetics of monolayers.
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Affiliation(s)
- Feng Wei
- Institution for Interdisciplinary Research
- Jianghan University
- Wuhan
- China
| | - Wei Xiong
- Institution for Interdisciplinary Research
- Jianghan University
- Wuhan
- China
| | - Wenhui Li
- Institution for Interdisciplinary Research
- Jianghan University
- Wuhan
- China
| | - Wangting Lu
- Institution for Interdisciplinary Research
- Jianghan University
- Wuhan
- China
| | - Heather C. Allen
- Department of Chemistry and Biochemistry
- The Ohio State University
- Columbus
- USA
| | - Wanquan Zheng
- Institution for Interdisciplinary Research
- Jianghan University
- Wuhan
- China
- Institut des Sciences Moléculaires d'Orsay
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23
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Murate M, Abe M, Kasahara K, Iwabuchi K, Umeda M, Kobayashi T. Transbilayer lipid distribution in nano scale. J Cell Sci 2015; 128:1627-38. [DOI: 10.1242/jcs.163105] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 02/02/2015] [Indexed: 01/19/2023] Open
Abstract
There are a limited number of methods to examine transbilayer lipid distribution in biomembranes. We employed freeze-fracture replica labelling immunoelectron microscopy in combination with multiple lipid-binding peptide/proteins to examine both transbilayer and lateral distribution of various phospholipids in mammalian cells. Our results indicate that phospholipids are exclusively distributed either in the outer or inner leaflet of human red blood cell (RBC) membranes. In contrast, in nucleated cells such as human skin fibroblasts and neutrophils, sphingomyelin was distributed in both leaflets while exhibiting characteristic lipid domains in the inner leaflet. Similar to RBC, lipid asymmetry was maintained both in resting and thrombin-activated platelets. However, the microparticles released from thrombin-activated platelets lost membrane asymmetry. Our results suggest that the microparticles were shed from platelet plasma membrane domains enriched with phosphatidylserine/phosphatidylinositol at the outer leaflet. These findings underscore the strict regulation and cell-type specificity of lipid asymmetry in the plasma membrane.
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24
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Rzeźnicka II, Pandey R, Schleeger M, Bonn M, Weidner T. Formation of lysozyme oligomers at model cell membranes monitored with sum frequency generation spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7736-7744. [PMID: 24941083 DOI: 10.1021/la5010227] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A growing number of studies suggest that the formation of toxic oligomers, precursors of amyloid fibrils, is initiated at the cell membrane and not in the cytosolic compartments of the cell. Studies of membrane-induced protein oligomerization are challenging due to the difficulties of probing small numbers of proteins present at membrane surfaces. Here, we employ surface-sensitive vibrational sum frequency generation (VSFG) to investigate the secondary structure of lysozyme at the surface of lipid monolayers. We investigate lysozyme aggregation at negatively charged 1,2-dipalmitoyl-sn-glycero-3-(phospho-rac-1-glycerol) (DPPG) lipid monolayers under different pH conditions. The changes in the molecular vibrations of lipids, proteins, and water as a function of pH and surface pressure allow us to simultaneously monitor details of the conformation state of lysozyme, the organization of lipids, and the state of lipid-bound water. At pH = 6 lysozyme induces significant disordering of the lipid layer, and it exists in two states: a monomeric state with a predominantly α-helix content and an oligomeric (za-mer) state. At pH ≤ 3, all membrane-bound lysozyme self-associates into oligomers characterized by an antiparallel β-sheet structure. This is different from the situation in bulk solution, for which circular dichroism (CD) shows that the protein maintains an α-helix conformation, under both neutral and acidic pH conditions. The transition from monomers to oligomers is also associated with a decreased hydration of the lipid monolayer resulting in an increase of the lipid acyl chains ordering. The results indicate that oligomerization requires cooperative action between lysozyme incorporated into the lipid membrane and peripherally adsorbed lysozyme and is associated with the membrane dehydration and lipid reorganization. Membrane-bound oligomers with antiparallel β-sheet structure are found to destabilize lipid membranes.
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Affiliation(s)
- I I Rzeźnicka
- Department of Chemistry, Graduate School of Science, 6-3 Aramaki Aza-Aoba, Aoba-ku, Tohoku University , Sendai, Japan
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25
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Lhor M, Bernier SC, Horchani H, Bussières S, Cantin L, Desbat B, Salesse C. Comparison between the behavior of different hydrophobic peptides allowing membrane anchoring of proteins. Adv Colloid Interface Sci 2014; 207:223-39. [PMID: 24560216 PMCID: PMC4028306 DOI: 10.1016/j.cis.2014.01.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 01/11/2014] [Accepted: 01/13/2014] [Indexed: 10/25/2022]
Abstract
Membrane binding of proteins such as short chain dehydrogenase reductases or tail-anchored proteins relies on their N- and/or C-terminal hydrophobic transmembrane segment. In this review, we propose guidelines to characterize such hydrophobic peptide segments using spectroscopic and biophysical measurements. The secondary structure content of the C-terminal peptides of retinol dehydrogenase 8, RGS9-1 anchor protein, lecithin retinol acyl transferase, and of the N-terminal peptide of retinol dehydrogenase 11 has been deduced by prediction tools from their primary sequence as well as by using infrared or circular dichroism analyses. Depending on the solvent and the solubilization method, significant structural differences were observed, often involving α-helices. The helical structure of these peptides was found to be consistent with their presumed membrane binding. Langmuir monolayers have been used as membrane models to study lipid-peptide interactions. The values of maximum insertion pressure obtained for all peptides using a monolayer of 1,2-dioleoyl-sn-glycero-3-phospho-ethanolamine (DOPE) are larger than the estimated lateral pressure of membranes, thus suggesting that they bind membranes. Polarization modulation infrared reflection absorption spectroscopy has been used to determine the structure and orientation of these peptides in the absence and in the presence of a DOPE monolayer. This lipid induced an increase or a decrease in the organization of the peptide secondary structure. Further measurements are necessary using other lipids to better understand the membrane interactions of these peptides.
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Affiliation(s)
- Mustapha Lhor
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Sarah C Bernier
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Habib Horchani
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Sylvain Bussières
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Line Cantin
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Bernard Desbat
- CBMN-UMR 5248 CNRS, Université de Bordeaux, IPB, Allée Geoffroy Saint Hilaire, 33600 Pessac, France
| | - Christian Salesse
- CUO-Recherche, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, Département d'ophtalmologie, Faculté de médecine, Université Laval, Québec, Québec G1V 0A6, Canada; Regroupement stratégique PROTEO, Université Laval, Québec, Québec G1V 0A6, Canada.
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26
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Keszthelyi T, Hill K, Kiss É. Interaction of Phospholipid Langmuir Monolayers with an Antibiotic Peptide Conjugate. J Phys Chem B 2013; 117:6969-79. [DOI: 10.1021/jp401533c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Tamás Keszthelyi
- Institute of Molecular Pharmacology,
Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1025 Budapest, Pusztaszeri út
59-67, Hungary
| | - Katalin Hill
- Laboratory
of Interfaces and
Nanostructures, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, H-1518 Budapest
112, Hungary
| | - Éva Kiss
- Laboratory
of Interfaces and
Nanostructures, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, H-1518 Budapest
112, Hungary
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27
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Lis D, Guthmuller J, Champagne B, Humbert C, Busson B, Peremans A, Cecchet F. Vibrational Sum-Frequency Generation Activity of a 2,4-Dinitrophenyl Phospholipid Hybrid Bilayer: Retrieving Orientational Parameters from a DFT Analysis of Experimental Data. Chemphyschem 2013; 14:1227-36. [DOI: 10.1002/cphc.201201063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Indexed: 12/18/2022]
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28
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Duramycin exhibits antiproliferative properties and induces apoptosis in tumour cells. Blood Coagul Fibrinolysis 2013; 23:396-401. [PMID: 22543977 DOI: 10.1097/mbc.0b013e3283538875] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Duramycin is a polypeptide that binds specifically to phosphatidylethanolamine (PE) on cell surfaces with high affinity, and has been shown to disrupt tumour cell surface-based coagulation and exhibit weak antimicrobial activity. The aim of the present study was to characterize the effect of duramycin on tumour cell proliferation and viability. Duramycin was used to detect phosphatidylethanolamine expression on cell lines by flow cytometry. Cells were cultured in the presence of duramycin and proliferation and cell viability assessed. Electron microscopy and confocal microscopy were utilized to investigate cell membrane structure after duramycin treatment. Pancreatic tumour cells were shown to express phosphatidylethanolamine on their cell surfaces by specific labelling with duramycin. Phosphatidylethanolamine expression was generally increased in apoptotic cells and more so in necrotic cells. Cells cultured in the presence of duramycin showed increasing levels of apoptosis and ultimately necrosis with increasing duramycin concentrations, and cell proliferation was reduced in a duramycin dose-dependent manner between 0.125 and 12.5 μmol/l. Tissue factor expression was also reduced when cells were cultured in the presence of duramycin. Cells imaged by electron microscopy were fragile, suggesting that membrane integrity was compromised by duramycin, although no obvious differences in membrane structure were observed by live cell confocal imaging. Duramycin induced apoptosis and exhibited antiproliferative and anticoagulant effects on pancreatic tumour cells, most probably by disrupting cell membrane structure and/or function.
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29
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Prudovsky I, Kumar TKS, Sterling S, Neivandt D. Protein-phospholipid interactions in nonclassical protein secretion: problem and methods of study. Int J Mol Sci 2013; 14:3734-72. [PMID: 23396106 PMCID: PMC3588068 DOI: 10.3390/ijms14023734] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 12/30/2022] Open
Abstract
Extracellular proteins devoid of signal peptides use nonclassical secretion mechanisms for their export. These mechanisms are independent of the endoplasmic reticulum and Golgi. Some nonclassically released proteins, particularly fibroblast growth factors (FGF) 1 and 2, are exported as a result of their direct translocation through the cell membrane. This process requires specific interactions of released proteins with membrane phospholipids. In this review written by a cell biologist, a structural biologist and two membrane engineers, we discuss the following subjects: (i) Phenomenon of nonclassical protein release and its biological significance; (ii) Composition of the FGF1 multiprotein release complex (MRC); (iii) The relationship between FGF1 export and acidic phospholipid externalization; (iv) Interactions of FGF1 MRC components with acidic phospholipids; (v) Methods to study the transmembrane translocation of proteins; (vi) Membrane models to study nonclassical protein release.
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Affiliation(s)
- Igor Prudovsky
- Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA
| | | | - Sarah Sterling
- Department of Chemical and Biological Engineering, University of Maine, Orono, ME 04469, USA; E-Mails: (S.S.); (D.N.)
| | - David Neivandt
- Department of Chemical and Biological Engineering, University of Maine, Orono, ME 04469, USA; E-Mails: (S.S.); (D.N.)
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30
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Hąc-Wydro K, Lenartowicz R, Dynarowicz-Łątka P. The influence of plant stanol (β-sitostanol) on inner leaflet of human erythrocytes membrane modeled with the Langmuir monolayer technique. Colloids Surf B Biointerfaces 2013; 102:178-88. [DOI: 10.1016/j.colsurfb.2012.07.048] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Revised: 06/27/2012] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
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31
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Zhai X, Momsen WE, Malakhov DA, Boldyrev IA, Momsen MM, Molotkovsky JG, Brockman HL, Brown RE. GLTP-fold interaction with planar phosphatidylcholine surfaces is synergistically stimulated by phosphatidic acid and phosphatidylethanolamine. J Lipid Res 2013; 54:1103-13. [PMID: 23369752 DOI: 10.1194/jlr.m034744] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Among amphitropic proteins, human glycolipid transfer protein (GLTP) forms a structurally-unique fold that translocates on/off membranes to specifically transfer glycolipids. Phosphatidylcholine (PC) bilayers with curvature-induced packing stress stimulate much faster glycolipid intervesicular transfer than nonstressed PC bilayers raising questions about planar cytosol-facing biomembranes being viable sites for GLTP interaction. Herein, GLTP-mediated desorption kinetics of fluorescent glycolipid (tetramethyl-boron dipyrromethene (BODIPY)-label) from lipid monolayers are assessed using a novel microfluidics-based surface balance that monitors lipid lateral packing while simultaneously acquiring surface fluorescence data. At biomembrane-like packing (30-35 mN/m), GLTP uptake of BODIPY-glycolipid from POPC monolayers was nearly nonexistent but could be induced by reducing surface pressure to mirror packing in curvature-stressed bilayers. In contrast, 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE) matrices supported robust BODIPY-glycolipid uptake by GLTP at both high and low surface pressures. Unexpectedly, negatively-charged cytosol-facing lipids, i.e., phosphatidic acid and phosphatidylserine, also supported BODIPY-glycolipid uptake by GLTP at high surface pressure. Remarkably, including both 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphate (5 mol%) and POPE (15 mol%) in POPC synergistically activated GLTP at high surface pressure. Our study shows that matrix lipid headgroup composition, rather than molecular packing per se, is a key regulator of GLTP-fold function while demonstrating the novel capabilities of the microfluidics-based film balance for investigating protein-membrane interfacial interactions.
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Affiliation(s)
- Xiuhong Zhai
- The Hormel Institute, University of Minnesota, Austin, MN, USA
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32
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Syryamina VN, De Zotti M, Peggion C, Formaggio F, Toniolo C, Raap J, Dzuba SA. A Molecular View on the Role of Cholesterol upon Membrane Insertion, Aggregation, and Water Accessibility of the Antibiotic Lipopeptide Trichogin GA IV As Revealed by EPR. J Phys Chem B 2012; 116:5653-60. [DOI: 10.1021/jp301660a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Victoria N. Syryamina
- Institute
of Chemical Kinetics
and Combustion, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Marta De Zotti
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Cristina Peggion
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Fernando Formaggio
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Claudio Toniolo
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Jan Raap
- Leiden Institute
of Chemistry,
Gorlaeus Laboratories, University of Leiden, 2300 RA Leiden, The Netherlands
| | - Sergei A. Dzuba
- Institute
of Chemical Kinetics
and Combustion, Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Physics, Novosibirsk State University, 630090 Novosibirsk, Russia
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33
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Burman R, Strömstedt AA, Malmsten M, Göransson U. Cyclotide–membrane interactions: Defining factors of membrane binding, depletion and disruption. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2665-73. [DOI: 10.1016/j.bbamem.2011.07.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 06/23/2011] [Accepted: 07/01/2011] [Indexed: 10/17/2022]
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