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Deleray AC, Kramer JR. Biomimetic Glycosylated Polythreonines by N-Carboxyanhydride Polymerization. Biomacromolecules 2022; 23:1453-1461. [PMID: 35104406 DOI: 10.1021/acs.biomac.2c00020] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glycosylated threonine (Thr) is a structural motif found in seemingly disparate natural proteins from deep-sea collagen to mucins. Synthetic mimics of these important proteins are of great interest in biomedicine. Such materials also provide ready access to probe the contributions of individual amino acids to protein structure in a controlled and tunable manner. N-Carboxyanhydride (NCA) polymerization is one major route to such biomimetic polypeptides. However, challenges in the preparation and polymerization of Thr NCAs have impeded obtaining such structures. Here, we present optimized routes to several glycosylated and acetylated Thr NCAs of high analytical purity. Transition metal catalysis produced tunable homo-, statistical, and block-polypeptides with predictable chain lengths and low dispersities. We conducted structural work to examine their aqueous conformations and found that a high content of free OH Thr induces the formation of water-insoluble β-sheets. However, glycosylation appears to induce a polyproline II-type helical conformation, which sheds light on the role of glyco-Thr in rigid proteins such as mucins and collagen.
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Affiliation(s)
- Anna C Deleray
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jessica R Kramer
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112, United States
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TRAIL encapsulated to polypeptide-crosslinked nanogel exhibits increased anti-inflammatory activities in Klebsiella pneumoniae-induced sepsis treatment. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 102:85-95. [DOI: 10.1016/j.msec.2019.04.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 04/09/2019] [Accepted: 04/09/2019] [Indexed: 12/18/2022]
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3
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Hou SS, Fan NS, Tseng YC, Jan JS. Self-Assembly and Hydrogelation of Coil–Sheet Poly(l-lysine)-block-poly(l-threonine) Block Copolypeptides. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01265] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Sheng-Shu Hou
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan 70101, Taiwan
| | - Nai-Shin Fan
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Yu-Chao Tseng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Jeng-Shiung Jan
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan 70101, Taiwan
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One-dimensional poly(L-lysine)-block-poly(L-threonine) assemblies exhibit potent anticancer activity by enhancing membranolysis. Acta Biomater 2017; 55:283-295. [PMID: 28412555 DOI: 10.1016/j.actbio.2017.04.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 12/19/2022]
Abstract
Herein, we report the oncolytic activity of cationic, one-dimensional (1D) fibril assemblies formed from coil-sheet poly(L-lysine)-block-poly(L-threonine) (PLL-b-PLT) block copolypeptides for cancer therapy. The 1D fibril assemblies can efficiently interact with negatively charged cellular and mitochondrial membranes via electrostatic interactions, leading to necrosis via membrane lysis and apoptosis via the mitochondria-lytic effect. The concept is analogous to that of 1D drug carriers that exhibit enhanced cell penetration. In comparison to free PLL chains, PLL-b-PLT fibril assemblies exhibit selective cytotoxicity toward cancer cells, low hemolysis activity, enhanced membranolytic activity, and a different apoptosis pathway, which may be due to differences in the peptide-membrane interactions. Antitumor studies using a metastatic LL2 lung carcinoma model indicate that the fibril assemblies significantly inhibited tumor growth, improved survival in tumor-bearing mice and suppressed lung metastasis without obvious body weight loss. An additive efficacy was also observed for treatment with both PLL-b-PLT and cisplatin. These results support the feasibility of using 1D fibril assemblies as potential apoptotic anticancer therapeutics. STATEMENT OF SIGNIFICANCE We report that cationic, one-dimensional (1D) fibril assemblies formed by coil-sheet poly(L-lysine)-block-poly(L-threonine) (PLL-b-PLT) block copolypeptides exhibited potent anticancer activity by enhancing membranolysis. The 1D fibril assemblies can efficiently interact with negatively charged cellular and mitochondrial membranes via electrostatic interactions, leading to necrosis via membrane lysis and apoptosis via mitochondria-lytic effect. Moreover, the fibril assemblies exhibited low hemolytic activity and selective cytotoxicity toward cancer cell, which is advantageous as compared to PLL and most antimicrobial/anticancerous peptides. This study provides a new concept of using cationic, 1D fibril assemblies for cancer therapy.
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Hou SS, Hsu YY, Lin JH, Jan JS. Alkyl-poly(l-threonine)/Cyclodextrin Supramolecular Hydrogels with Different Molecular Assemblies and Gel Properties. ACS Macro Lett 2016; 5:1201-1205. [PMID: 35614745 DOI: 10.1021/acsmacrolett.6b00716] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report alkyl-poly(l-threonine)/cyclodextrin (alkyl-PLT/CD) supramolecular hydrogels with different molecular assemblies. Their properties are determined by the interplay between host-guest chemistry and hydrogen-bonding interactions. The gelation process was mainly dictated by the formation of alkyl chain/CD inclusion complex and PLT chain conformation. The dodecyl-PLT20/α-CD hydrogel exhibited laminar packing due to the sheet-to-coil conformational change upon forming inclusion complex. The hexadecyl-PLT20/β-CD hydrogel exhibited ribbon-like assemblies instead, because the peptide adopted mainly sheet conformation. The gel-to-sol transition occurred upon increasing temperature because of the decrease in hydrogen-bonding interactions and partly conformational change.
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Affiliation(s)
- Sheng-Shu Hou
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Yu-Yun Hsu
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Jia-Hsien Lin
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Jeng-Shiung Jan
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
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6
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Guzzetti KA, Brizuela AB, Romano E, Brandán SA. Structural and vibrational study on zwitterions of l-threonine in aqueous phase using the FT-Raman and SCRF calculations. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.04.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Synthesis and Self-Assembly of Well-Defined Block Copolypeptides via Controlled NCA Polymerization. HIERARCHICAL MACROMOLECULAR STRUCTURES: 60 YEARS AFTER THE STAUDINGER NOBEL PRIZE II 2013. [DOI: 10.1007/12_2013_234] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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8
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Cheng J, Deming TJ. Synthesis of polypeptides by ring-opening polymerization of α-amino acid N-carboxyanhydrides. Top Curr Chem (Cham) 2011; 310:1-26. [PMID: 21647839 DOI: 10.1007/128_2011_173] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This chapter summarizes methods for the synthesis of polypeptides by ring-opening polymerization. Traditional and recently improved methods used to polymerize α-amino acid N-carboxyanhydrides (NCAs) for the synthesis of homopolypeptides are described. Use of these methods and strategies for the preparation of block copolypeptides and side-chain-functionalized polypeptides are also presented, as well as an analysis of the synthetic scope of different approaches. Finally, issues relating to obtaining highly functional polypeptides in pure form are detailed.
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Affiliation(s)
- Jianjun Cheng
- Department of Materials Science and Engineering, University of Illinois, Champaign, IL 61801, USA
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Zwanziger D, Böhme I, Lindner D, Beck-Sickinger AG. First selective agonist of the neuropeptide Y1-receptor with reduced size. J Pept Sci 2009; 15:856-66. [DOI: 10.1002/psc.1188] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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10
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Masman MF, Lovas S, Murphy RF, Enriz RD, Rodríguez AM. Conformational Preferences of N-Acetyl-l-leucine-N‘-methylamide. Gas-Phase and Solution Calculations on the Model Dipeptide. J Phys Chem A 2007; 111:10682-91. [PMID: 17887655 DOI: 10.1021/jp0716886] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A DFT study of N-acetyl-l-leucine-N'-methylamide conformers in the gas phase and in solution was carried out. The theoretical computational analysis revealed 43 different conformations at the B3LYP/6-31G(d) level of theory in the gas phase. In addition, the effects of three solvents (water, acetonitrile, and chloroform) were included in the calculations using the isodensity polarizable continuum model (IPCM) and the Poisson-Boltzmann self-consistent reaction field (PB-SCRF) method. The stability order of the different conformers in solution has been analyzed. The theoretical results were compared with some experimental data (X-ray, IR, and NMR).
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Affiliation(s)
- Marcelo F Masman
- Departamento de Química, Universidad Nacional de San Luis, Chacabuco 917, 5700 San Luis, Argentina
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Deming TJ. Methodologies for preparation of synthetic block copolypeptides: materials with future promise in drug delivery. Adv Drug Deliv Rev 2002; 54:1145-55. [PMID: 12384312 DOI: 10.1016/s0169-409x(02)00062-5] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This article summarizes recent developments in the synthesis of copolypeptides, focusing on the realization of living polymerizations that allow preparation of materials with excellent attributes for drug delivery. Traditional methods used to polymerize alpha-amino acid-N-carboxyanhydrides (NCAs) are described, and limitations in the utility of these systems for the preparation of polypeptides are discussed. A system utilizing transition metal catalysis for polypeptide synthesis is described that allows preparation of materials that begin to rival biologically produced counterparts in terms of complexity and purity. Overall, new developments in NCA and beta-lactam polymerizations hold tremendous promise now that block copolypeptides of controlled dimensions (molecular weight, sequence, composition, and molecular weight distribution) can be prepared. Such well-defined polymers should greatly assist in the development of new drug carriers with increased function.
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Affiliation(s)
- Timothy J Deming
- Departments of Materials and Chemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
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12
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Barth A. The infrared absorption of amino acid side chains. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2001; 74:141-73. [PMID: 11226511 DOI: 10.1016/s0079-6107(00)00021-3] [Citation(s) in RCA: 885] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Amino acid side chains play fundamental roles in stabilising protein structures and in catalysing enzymatic reactions. These fields are increasingly investigated by infrared spectroscopy at the molecular level. To help the interpretation of the spectra, a review of the infrared absorption of amino acid side chains in H(2)O and 2H(2)O is given. The spectral region of 2600-900cm(-1) is covered.
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Affiliation(s)
- A Barth
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Theodor Stern-Kai 7, Haus 74, D-60590 Frankfurt am Main, Germany.
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Abstract
Many natural polymeric materials (particularly structural proteins) display a hierarchy of structure over several length scales. Block copolymers are able to self-assemble into ordered nanostructures, but the random-coiled nature of their polymer chains usually suppresses any further levels of organization. The use of components with regular structures, such as rigid-rod polymers, can increase the extent of spatial organization in self-assembling materials. But the synthesis of such polymeric components typically involves complicated reaction steps that are not suitable for large-scale production. Proteins form hierarchically organized structures in which the fundamental motifs are generally alpha-helical coils and beta-sheets. Attempts to synthesize polypeptides with well-defined amino-acid sequences, which might adopt similar organized structures, have been plagued by unwanted side reactions that give rise to products with a wide range of molecular weights, hampering the formation of well-defined peptide block copolymers. Here I describe a polymerization strategy that overcomes these difficulties by using organonickel initiators which suppress chain-transfer and termination side reactions. This approach allows the facile synthesis of block copolypeptides with well-defined sequences, which might provide new peptide-based biomaterials with potential applications in tissue engineering, drug delivery and biomimetic composite formation.
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Affiliation(s)
- T J Deming
- Department of Materials, University of California, Santa Barbara 93106, USA.
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15
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Osthoff G, Nel AJ. Far-UV CD spectroscopy, IR spectroscopy, and immunological properties of synthetic peptides, including an amphipathic alpha-helical peptide from bovine phospholipase A2. Biopolymers 1990; 29:311-6. [PMID: 1691928 DOI: 10.1002/bip.360290203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The immunological properties of bovine phospholipase A2 were investigated in order to locate possible sequential epitopes. Polyvalent antiserum raised against the enzyme was tested for its interaction with synthetic peptides derived from regions adopting hydrogen-bonded secondary structures within the tertiary structure of phospholipase A2. The conformations of each peptide in various solvents were determined by CD and ir spectroscopy in order to relate immunological to structural properties. It was found that sequential epitopes are absent in this enzyme, but that region 90-109 could be a possible T-cell epitope through the formation of an amphipathic alpha-helix.
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Affiliation(s)
- G Osthoff
- Division of Processing and Chemical Manufacturing Technology, CSIR, Pretoria, Republic of South Africa
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16
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Polymeric sequences reveal a functional interrelationship between hydrophobicity and length of signal peptides. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39882-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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17
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Fasman GD. The road from poly(alpha-amino acids) to the prediction of protein conformation. Biopolymers 1987; 26 Suppl:S59-79. [PMID: 3580501 DOI: 10.1002/bip.360260009] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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18
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Kubota S, Ikeda K, Yang JT. Conformation of sequential and random copolypeptides of lysine and alanine in sodium dodecyl sulfate solution. Biopolymers 1983; 22:2219-36. [PMID: 6640071 DOI: 10.1002/bip.360221008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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19
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Ptitsyn OB, Finkelstein AV. Theory of protein secondary structure and algorithm of its prediction. Biopolymers 1983; 22:15-25. [PMID: 6673754 DOI: 10.1002/bip.360220105] [Citation(s) in RCA: 172] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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20
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Applequist J. Theoretical π-π* absorption and circular dichroic spectra of polypeptide β-structures. Biopolymers 1982. [DOI: 10.1002/bip.360210405] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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21
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Wu CS, Yang JT. Sequence-dependent conformations of short polypeptides in a hydrophobic environment. Mol Cell Biochem 1981; 40:109-22. [PMID: 7311970 DOI: 10.1007/bf00224754] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Surfactants, which provide a hydrophobic environment, may induce an ordered conformation in polypeptides and proteins that contain a sequence with helix-or beta-forming potential. This hypothesis has been illustrated in circular dichroic studies of oligopeptides and short polypeptides. These peptide-surfactant complexes can form (1) a helix, (2) a beta-form, (3) either form (depending on experimental conditions), or can remain in (4) an ordered form. The induced helix is stable in a surfactant solution below or above its critical micellar concentration, whereas the induced beta-form is usually converted back to an unordered form when the surfactant used is above its critical micellar concentration, or it is transformed into a helix in excess surfactant solution if the peptide has both the helix- and beta-forming potential. In most cases the observed conformations agree with those predicted from the amino acid sequences of the peptides. The induced conformation of a peptide can be destabilized by charges on the side groups having the same sign as that of surfactant ions. Disulfide bonds can inhibit the formation of induced conformation because of steric hindrance. The terminal effect can prevent a peptide from forming an ordered conformation near the NH2- and COOH-terminus.
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22
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Sederel WL, Bantjes A, Feijen J, Anderson JM. Solid-state conformation of copolymers of ?-benzyl-L-aspartate withL-alanine,L-leucine,L-valine, ?-benzyl-L-glutamate, or ?-carbobenzoxy-L-lysine. Biopolymers 1980. [DOI: 10.1002/bip.1980.360190905] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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23
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Tomiyama T, Ikeda S. The β-Conformation of Poly(S-[(3-hydroxypropyl)-carbamoylmethyl]-L-cysteine) in Aqueous Mixtures of D2O, Aliphatic Alcohols, and Acetic Acid. Polym J 1980. [DOI: 10.1295/polymj.12.511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Widmer U, Lorenzi GP, Pino P. The influence of asymmetric carbon atoms of the side chains on the conformational properties of polypeptides: Comparison of diastereomeric homooligopeptides ofL-isoleucine andD-alloisoleucine. Biopolymers 1979. [DOI: 10.1002/bip.1979.360180202] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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26
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Naider F, Becker JM, Ribeiro A, Goodman M. The effect of homologos amini acid replacement on the conformation of oligopeptides. III. CD studies on co-oligopeptides of methionine and valine or methionine and glycine in organic solution. Biopolymers 1978. [DOI: 10.1002/bip.1978.360170914] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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27
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Cardinaux F, Howard JC, Taylor GT, Scheraga HA. Block copolymers of amino acids. I. Synthesis and structure of copolymers of L-alanine or L-phenylalanine with D,L-Lysine-d7 or D,L-lysine. Biopolymers 1977; 16:2005-28. [PMID: 901924 DOI: 10.1002/bip.1977.360160914] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Howard JC, Cardinaux F, Scheraga HA. Block copolymers of amino acids. II. Physicochemical data on copolymers containing L-alanine or L-phenylalanine. Biopolymers 1977; 16:2029-51. [PMID: 901925 DOI: 10.1002/bip.1977.360160915] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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29
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Arfmann HA, Labitzke R, Wagner KG. Conformational properties of L-leucine, L-isoleucine, and L-norleucine side chains in L-lysine copolymers. Biopolymers 1977; 16:1815-26. [PMID: 890071 DOI: 10.1002/bip.1977.360160815] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Walter B, Fasman GD. The random coil goes to beta transition of copolymers of L-lysine and L-isoleucine: potentiometric titration and circular dischroism studies. Biopolymers 1977; 16:17-32. [PMID: 843591 DOI: 10.1002/bip.1977.360160103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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33
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Schwartz AM, Fasman GD. The beta association of (DLLys)10-(LVal)20-(DLLys)10: an Nmr study. Biopolymers 1976; 15:1377-95. [PMID: 949540 DOI: 10.1002/bip.1976.360150711] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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35
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36
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Green NM, Flanagan MT. The prediction of the conformation of membrane proteins from the sequence of amino acids. Biochem J 1976; 153:729-32. [PMID: 942384 PMCID: PMC1172643 DOI: 10.1042/bj1530729] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The methods of Chou & Fasman [Biochemistry (1974) 13, 211-222, 222-245] and of Lim [J. Mol. Biol. (1974)88, 857-872, 873-894] for predicting secondary structure from amino acid sequence have been applied to five predominantly helical membrane-associated peptides. The predictions from the method of Lim (1974a,b) are consistent with the experimental observations, whereas those from Chou & Fasman (1974a,b), although not inconsistent with alpha-helix, favour a beta-structure for several very hydrophobic regions. The results may be rationalized in terms of the effect of the solvent on the conformation of a polypeptide.
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37
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Ito K, Fasman GD. Poly(L-valine). Conformational dependence on the degree of polymerization: infrared studies. Biopolymers 1975; 14:1755-67. [PMID: 1156663 DOI: 10.1002/bip.1975.360140815] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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38
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Mandel R, Fasman GD. The random coil leads to beta transition of copolymers of L-lysine and L-valine: potentiometric titration and circular dichroism studies. Biopolymers 1975; 14:1633-49. [PMID: 239771 DOI: 10.1002/bip.1975.360140808] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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