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Lobanov MY, Pereyaslavets LB, Likhachev IV, Matkarimov BT, Galzitskaya OV. Is there an advantageous arrangement of aromatic residues in proteins? Statistical analysis of aromatic interactions in globular proteins. Comput Struct Biotechnol J 2021; 19:5960-5968. [PMID: 34849200 PMCID: PMC8604681 DOI: 10.1016/j.csbj.2021.10.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/11/2021] [Accepted: 10/28/2021] [Indexed: 11/18/2022] Open
Abstract
The aim of this study was to evaluate the favorability of different conformations of aromatic residues in proteins by analysing the occurrence of particular conformations. The clustering of protein structures from the Protein Data Bank (PDB) was performed. Conformations of interacting aromatic residues were analyzed for 511 282 pairs in 35 493 protein structures sharing less than 50% identity. Pairs with a parallel arrangement of aromatic residues made up 6.2% of all possible ones, which was twice as much as expected. Pairs with a perpendicular arrangement of aromatic residues made up 25%. We demonstrate that the most favorable arrangement was at an angle of 60° between the interacting aromatic residues. Among all possible aromatic pairs, the His-His pair was twice as frequent as expected, and the His-Phe pair was less frequent than expected. A server (CARP - Contacts of Aromatic Residues in Proteins) has been created for calculating essential structural features of interacting aromatic residues in proteins: http://bioproteom.protres.ru/arom_q_prog/.
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Affiliation(s)
- Mikhail Yu. Lobanov
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
| | - Leonid B. Pereyaslavets
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
| | - Ilya V. Likhachev
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Institute of Mathematical Problems of Biology, Russian Academy of Sciences, Keldysh Institute of Applied Mathematics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
| | | | - Oxana V. Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Corresponding author at: Laboratory of Bioinformatics and Proteomics, Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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2
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Structural and functional dynamics of tyrosine amino acid in phycocyanin of hot-spring cyanobacteria: A possible pathway for internal energy transfer. GENE REPORTS 2016. [DOI: 10.1016/j.genrep.2016.09.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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Makwana KM, Mahalakshmi R. Nature of aryl-tyrosine interactions contribute to β-hairpin scaffold stability: NMR evidence for alternate ring geometry. Phys Chem Chem Phys 2016; 17:4220-30. [PMID: 25569770 DOI: 10.1039/c4cp04991h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The specific contribution of the acidic-aromatic β-sheet favouring amino acid tyrosine to the stability of short octapeptide β-hairpin structures is presented here. Solution NMR analysis in near-apolar environments suggests the energetically favourable mode of interaction to be T-shaped face-to-edge (FtE) and that a Trp-Tyr interacting pair is the most stabilizing. Alternate aryl geometries also exist in solution, which readily equilibrate between a preferred π···π conformation to an aromatic-amide conformation, without any change in the backbone structure. While the phenolic ring is readily accommodated at the "edge" of FtE aryl interactions, it exhibits an overall lowered contribution to scaffold stability in the "face" orientation. Such differential tyrosine interactions are key to its dual nature in proteins.
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Affiliation(s)
- Kamlesh Madhusudan Makwana
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal-462023, India.
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4
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The Bright Future of Unconventional σ/π-Hole Interactions. Chemphyschem 2015; 16:2496-517. [DOI: 10.1002/cphc.201500314] [Citation(s) in RCA: 475] [Impact Index Per Article: 52.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Indexed: 01/25/2023]
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5
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Hussain HB, Wilson KA, Wetmore SD. Serine and Cysteine π-Interactions in Nature: A Comparison of the Frequency, Structure, and Stability of Contacts Involving Oxygen and Sulfur. Aust J Chem 2015. [DOI: 10.1071/ch14598] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Despite many DNA–protein π-interactions in high-resolution crystal structures, only four X–H···π or X···π interactions were found between serine (Ser) or cysteine (Cys) and DNA nucleobase π-systems in over 100 DNA–protein complexes (where X = O for Ser and X = S for Cys). Nevertheless, 126 non-covalent contacts occur between Ser or Cys and the aromatic amino acids in many binding arrangements within proteins. Furthermore, Ser and Cys protein–protein π-interactions occur with similar frequencies and strengths. Most importantly, due to the great stability that can be provided to biological macromolecules (up to –20 kJ mol–1 for neutral π-systems or –40 kJ mol–1 for cationic π-systems), Ser and Cys π-interactions should be considered when analyzing protein stability and function.
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de Sousa MM, Munteanu CR, Pazos A, Fonseca NA, Camacho R, Magalhães AL. Amino acid pair- and triplet-wise groupings in the interior of α-helical segments in proteins. J Theor Biol 2010; 271:136-44. [PMID: 21130100 DOI: 10.1016/j.jtbi.2010.11.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 11/03/2010] [Accepted: 11/23/2010] [Indexed: 10/18/2022]
Abstract
A statistical approach has been applied to analyse primary structure patterns at inner positions of α-helices in proteins. A systematic survey was carried out in a recent sample of non-redundant proteins selected from the Protein Data Bank, which were used to analyse α-helix structures for amino acid pairing patterns. Only residues more than three positions apart from both termini of the α-helix were considered as inner. Amino acid pairings i, i+k (k=1, 2, 3, 4, 5), were analysed and the corresponding 20×20 matrices of relative global propensities were constructed. An analysis of (i, i+4, i+8) and (i, i+3, i+4) triplet patterns was also performed. These analysis yielded information on a series of amino acid patterns (pairings and triplets) showing either high or low preference for α-helical motifs and suggested a novel approach to protein alphabet reduction. In addition, it has been shown that the individual amino acid propensities are not enough to define the statistical distribution of these patterns. Global pair propensities also depend on the type of pattern, its composition and orientation in the protein sequence. The data presented should prove useful to obtain and refine useful predictive rules which can further the development and fine-tuning of protein structure prediction algorithms and tools.
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Affiliation(s)
- Miguel M de Sousa
- REQUIMTE/University of Porto, Faculty of Sciences, R. Campo Alegre 687, 4169-007 Porto, Portugal
| | - Cristian R Munteanu
- REQUIMTE/University of Porto, Faculty of Sciences, R. Campo Alegre 687, 4169-007 Porto, Portugal; Computer Science Faculty, University of A Coruña, Campus de Elviña S/N, 15071A Coruña, Spain
| | - Alejandro Pazos
- Computer Science Faculty, University of A Coruña, Campus de Elviña S/N, 15071A Coruña, Spain
| | - Nuno A Fonseca
- CRACS-INESC Porto L.A., R. Campo Alegre 1021/1055, 4169-007 Porto, Portugal
| | - Rui Camacho
- LIAAD-INESC-Porto, DEI and FEUP, R. Dr. Roberto Frias s/n, 4200-465 Porto, Portugal
| | - A L Magalhães
- REQUIMTE/University of Porto, Faculty of Sciences, R. Campo Alegre 687, 4169-007 Porto, Portugal
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8
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Coetsee M, Millar RP, Flanagan CA, Lu ZL. Identification of Tyr(290(6.58)) of the human gonadotropin-releasing hormone (GnRH) receptor as a contact residue for both GnRH I and GnRH II: importance for high-affinity binding and receptor activation. Biochemistry 2008; 47:10305-13. [PMID: 18771291 DOI: 10.1021/bi800911z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular modeling showed interactions of Tyr (290(6.58)) in transmembrane domain 6 of the GnRH receptor with Tyr (5) of GnRH I, and His (5) of GnRH II. The wild-type receptor exhibited high affinity for [Phe (5)]GnRH I and [Tyr (5)]GnRH II, but 127- and 177-fold decreased affinity for [Ala (5)]GnRH I and [Ala (5)]GnRH II, indicating that the aromatic ring in position 5 is crucial for receptor binding. The receptor mutation Y290F decreased affinity for GnRH I, [Phe (5)]GnRH I, GnRH II and [Tyr (5)]GnRH II, while Y290A and Y290L caused larger decreases, suggesting that both the para-OH and aromatic ring of Tyr (290(6.58)) are important for binding of ligands with aromatic residues in position 5. Mutating Tyr (290(6.58)) to Gln increased affinity for Tyr (5)-containing GnRH analogues 3-12-fold compared with the Y290A and Y290L mutants, suggesting a hydrogen-bond between Gln of the Y290Q mutant and Tyr (5) of GnRH analogues. All mutations had small effects on affinity of GnRH analogues that lack an aromatic residue in position 5. These results support direct interactions of the Tyr (290(6.58)) side chain with Tyr (5) of GnRH I and His (5) of GnRH II. Tyr (290(6.58)) mutations, except for Y290F, caused larger decreases in GnRH potency than affinity, indicating that an aromatic ring is important for the agonist-induced receptor conformational switch.
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Affiliation(s)
- Marla Coetsee
- MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, Scotland, United Kingdom
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Faure G, Bornot A, de Brevern AG. Protein contacts, inter-residue interactions and side-chain modelling. Biochimie 2008; 90:626-39. [DOI: 10.1016/j.biochi.2007.11.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Accepted: 11/22/2007] [Indexed: 10/22/2022]
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10
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Hatfield MPD, Palermo NY, Csontos J, Murphy RF, Lovas S. Quantum chemical quantification of weakly polar interaction energies in the TC5b miniprotein. J Phys Chem B 2008; 112:3503-8. [PMID: 18303883 DOI: 10.1021/jp077674h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The tertiary structure of the TC5b miniprotein is stabilized by inter-residue interactions of the Trp-cage, which is composed of a Tyr and several Pro residues surrounding a central Trp residue. The interactions include Ar-Ar (aromatic side-chain-aromatic side-chain), Ar-NH (aromatic side-chain-backbone amide), and CH-pi (aromatic side-chain-aliphatic hydrogen) interactions. In the present work, the strength of the weakly polar interactions found in the TC5b miniprotein was quantified using all of the available 38 NMR structures (1L2Y) from the Protein Data Bank with DFT quantum chemical calculations at the BHandHLYP/cc-pVTZ level of theory and molecular fragmentation with capping of the partial structures. The energies of interaction between the individual residues of the Trp-cage range between -5.85+/-1.41 and -21.30+/-0.88 kcal mol(-1), leading to a significant total structural stabilization energy of -52.13+/-2.56 kcal mol(-1) of which about 50% is from the weakly polar interactions. Furthermore, the strengths of the individual weakly polar interactions are between -2.32+/-0.17 and -2.93+/-0.12 kcal mol(-1) for the CH-pi interactions, between -2.48+/-0.97 and -3.09+/-1.02 kcal mol(-1) for the Ar-NH interaction and -2.74+/-1.06 kcal mol(-1) for the Ar-Ar interaction.
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11
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Chakrabarti P, Bhattacharyya R. Geometry of nonbonded interactions involving planar groups in proteins. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2007; 95:83-137. [PMID: 17629549 DOI: 10.1016/j.pbiomolbio.2007.03.016] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Accepted: 03/18/2007] [Indexed: 11/26/2022]
Abstract
Although hydrophobic interaction is the main contributing factor to the stability of the protein fold, the specificity of the folding process depends on many directional interactions. An analysis has been carried out on the geometry of interaction between planar moieties of ten side chains (Phe, Tyr, Trp, His, Arg, Pro, Asp, Glu, Asn and Gln), the aromatic residues and the sulfide planes (of Met and cystine), and the aromatic residues and the peptide planes within the protein tertiary structures available in the Protein Data Bank. The occurrence of hydrogen bonds and other nonconventional interactions such as C-H...pi, C-H...O, electrophile-nucleophile interactions involving the planar moieties has been elucidated. The specific nature of the interactions constraints many of the residue pairs to occur with a fixed sequence difference, maintaining a sequential order, when located in secondary structural elements, such as alpha-helices and beta-turns. The importance of many of these interactions (for example, aromatic residues interacting with Pro or cystine sulfur atom) is revealed by the higher degree of conservation observed for them in protein structures and binding regions. The planar residues are well represented in the active sites, and the geometry of their interactions does not deviate from the general distribution. The geometrical relationship between interacting residues provides valuable insights into the process of protein folding and would be useful for the design of protein molecules and modulation of their binding properties.
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Affiliation(s)
- Pinak Chakrabarti
- Department of Biochemistry and Bioinformatics Centre, Bose Institute, P-1/12 CIT Scheme VIIM, Kolkata 700054, India.
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12
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Palermo NY, Csontos J, Owen MC, Murphy RF, Lovas S. Aromatic-backbone interactions in model α-helical peptides. J Comput Chem 2007; 28:1208-14. [PMID: 17299770 DOI: 10.1002/jcc.20578] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The effects on helical stability of weak polar interactions between aromatic side-chains and the peptide backbone were examined. alpha-Helical model peptides, hexa-Ala, with sequential Tyr replacement, were investigated computationally to obtain the geometries and energetics of the interactions. Geometries were obtained with the B3LYP/6-31G* level of theory. Interaction energies were calculated using BHandHLYP/cc-pVTZ and an improved method to correct for basis set superposition error when fragmentation caused steric clashes. Both i, i + 1 and i, i - 4 interactions were observed when Tyr was in position i = 5. The position of the aromatic residue in the amino acid sequence was crucial in facilitating aromatic-backbone interactions. The distance between the center of the aromatic ring of Tyr and the individual interacting backbone atoms ranged from 3.65 to 5.50 A. The interactions have energies of the same order as hydrogen bonds and, thus, could have a significant impact on the stability of the helix.
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Affiliation(s)
- Nicholas Y Palermo
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska, USA
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Thomas A, Deshayes S, Decaffmeyer M, Van Eyck MH, Charloteaux B, Brasseur R. Prediction of peptide structure: how far are we? Proteins 2007; 65:889-97. [PMID: 17019719 DOI: 10.1002/prot.21151] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Rational design of peptides is a challenge, which would benefit from a better knowledge of the rules of sequence-structure-function relationships. Peptide structures can be approached by spectroscopy and NMR techniques but data from these approaches too frequently diverge. Structures can also be calculated in silico from primary sequence information using three algorithms: Pepstr, Robetta, and PepLook. The most recent algorithm, PepLook introduces indexes for evaluating structural polymorphism and stability. For peptides with converging experimental data, calculated structures from PepLook and, to a lesser extent from Pepstr, are close to NMR models. The PepLook index for polymorphism is low and the index for stability points out possible binding sites. For peptides with divergent experimental data, calculated and NMR structures can be similar or, can be different. These differences are apparently due to polymorphism and to different conditions of structure assays and calculations. The PepLook index for polymorphism maps the fragments encoding disorder. This should provide new means for the rational design of peptides.
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Affiliation(s)
- Annick Thomas
- Centre de Biophysique Moléculaire Numérique FSAGx, 2, Passage des Déportés, Gembloux 5030, Belgium.
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Meng HY, Thomas KM, Lee AE, Zondlo NJ. Effects of i and i+3 residue identity on cis-trans isomerism of the aromatic(i+1)-prolyl(i+2) amide bond: implications for type VI beta-turn formation. Biopolymers 2006; 84:192-204. [PMID: 16208767 DOI: 10.1002/bip.20382] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cis-trans isomerization of amide bonds plays critical roles in protein molecular recognition, protein folding, protein misfolding, and disease. Aromatic-proline sequences are particularly prone to exhibit cis amide bonds. The roles of residues adjacent to a tyrosine-proline residue pair on cis-trans isomerism were examined. A short series of peptides XYPZ was synthesized and cis-trans isomerism was analyzed. Based on these initial studies, a series of peptides XYPN, X = all 20 canonical amino acids, was synthesized and analyzed by NMR for i residue effects on cis-trans isomerization. The following effects were observed: (a) aromatic residues immediately preceding Tyr-Pro disfavor cis amide bonds, with K(trans/cis)= 5.7-8.0, W > Y > F; (b) proline residues preceding Tyr-Pro lead to multiple species, exhibiting cis-trans isomerization of either or both X-Pro amide bonds; and (c) other residues exhibit similar values of K(trans/cis) (= 2.9-4.2), with Thr and protonated His exhibiting the highest fraction cis. beta-Branched and short polar residues were somewhat more favorable in stabilizing the cis conformation. Phosphorylation of serine at the i position modestly increases the stability of the cis conformer. In addition, the effect of the i+3 residue was examined in a limited series of peptides TYPZ. NMR data indicated that aromatic residues, Pro, Asn, Ala, and Val at the i+3 residue all favor cis amide bonds, with aromatic residues and Asn favoring more compact phi at Tyr(cis) and Ala and Pro favoring more extended phi at Tyr(cis). D-Alanine at the i+3 position particularly disfavors cis amide bonds.
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Affiliation(s)
- Hai Yun Meng
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
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Mahalakshmi R, Raghothama S, Balaram P. NMR analysis of aromatic interactions in designed peptide beta-hairpins. J Am Chem Soc 2006; 128:1125-38. [PMID: 16433528 DOI: 10.1021/ja054040k] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Designed octapeptide beta-hairpins containing a central (D)Pro-Gly segment have been used as a scaffold to place the aromatic residues Tyr and Trp at various positions on the antiparallel beta-strands. Using a set of five peptide hairpins, aromatic interactions have been probed across antiparallel beta-sheets, in the non-hydrogen bonding position (Ac-L-Y-V-(D)P-G-L-Y/W-V-OMe: peptides 1 and 2), diagonally across the strands (Boc-Y/W-L-V-(D)P-G-W-L-V-OMe: peptides 3 and 6), and along the strands at positions i and i + 2 (Boc-L-L-V-(D)P-G-Y-L-W-OMe: peptide 4). Two peptides served as controls (Boc-L-L-V-(D)P-G-Y-W-V-OMe: peptide 5; Boc-L-Y-V-(D)P-G-L-L-V-OMe: peptide 7) for aromatic interactions. All studies have been carried out using solution NMR methods in CDCl(3) + 10% DMSO-d(6) and have been additionally examined in CD(3)OH for peptides 1 and 2. Inter-ring proton-proton nuclear Overhauser effects (NOEs) and upfield shifted aromatic proton resonances have provided firm evidence for specific aromatic interactions. Calculated NMR structures for peptides 1 and 2, containing aromatic pairs at facing non-hydrogen bonded positions, revealed that T-shaped arrangements of the interacting pairs of rings are favored, with ring current effects leading to extremely upfield chemical shifts and temperature dependences for specific aromatic protons. Anomalous far-UV CD spectra appeared to be a characteristic feature in peptides where the two aromatic residues are spatially proximal. The observation of the close approach of aromatic rings in organic solvents suggests that interactions of an electrostatic nature may be favored. This situation may be compared to the case of aqueous solutions, where clustering of aromatic residues is driven by solvophobic (hydrophobic) forces.
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Sacksteder CA, Bender SL, Barry BA. Role for bound water and CH-pi aromatic interactions in photosynthetic electron transfer. J Am Chem Soc 2005; 127:7879-90. [PMID: 15913378 DOI: 10.1021/ja050659a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photosystem I (PSI) is one of two photosynthetic reaction centers present in plants, algae, and cyanobacteria and catalyzes the reduction of ferredoxin and the oxidation of cytochrome c or plastocyanin. The PSI primary chlorophyll donor, which is oxidized in the primary electron-transfer events, is a heterodimer of chl a and a' called P700. It has been suggested that protein relaxation accompanies light-induced electron transfer in this reaction center (Dashdorj, N.; Xu, W.; Martinsson, P.; Chitnis, P. R.; Savikhin, S. Biophys. J. 2004, 86, 3121. Kim, S.; Sacksteder, C. A.; Bixby, K. A.; Barry, B. A. Biochemistry 2001, 40, 15384). To investigate the details of electron transfer and relaxation events in PSI, we have employed several experimental approaches. First, we report a pH-dependent viscosity effect on P700+ reduction; this result suggests a role for proton transfer in the PSI electron-transfer reactions. Second, we find that changes in hydration alter the rate of P700+ reduction and the interactions of P700 with the protein environment. This result suggests a role for bound water in electron transfer to P700+. Third, we present evidence that deuteration of the tyrosine aromatic side chain perturbs the vibrational spectrum, associated with P700+ reduction. We attribute this result to a linkage between CH-pi interactions and electron transfer to P700+.
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Affiliation(s)
- Colette A Sacksteder
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, St. Paul, Minnesota 55108, USA
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Pröpsting MJ, Kanapin H, Jacob R, Naim HY. A phenylalanine-based folding determinant in intestinal sucrase-isomaltase that functions in the context of a quality control mechanism beyond the endoplasmic reticulum. J Cell Sci 2005; 118:2775-84. [PMID: 15944403 DOI: 10.1242/jcs.02364] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phenotype II of congenital sucrase-isomaltase deficiency in man is characterized by a retention of the brush border protein sucrase-isomaltase (SI) in the ER/cis-Golgi intermediate compartment (ERGIC) and the cis-Golgi. The transport block is due to the substitution of a glutamine by a proline at amino acid residue 1098 that generates a temperature-sensitive mutant enzyme, SIQ1098P, the transport of which is regulated by several cycles of anterograde and retrograde transport between the ER and the cis-Golgi (Propsting, M. J., Jacob, R. and Naim, H. Y. (2003). J. Biol. Chem. 278, 16310-16314). A quality control beyond the ER has been proposed that implicates a retention signal or a folding determinant elicited by the Q1098P mutation. We have used alanine-scanning mutagenesis to screen upstream and downstream regions flanking Q1098 and identified a putative motif, F1093-x-F1095-x-x-x-F1099 that is likely to be implicated in sensing the folding and subsequent trafficking of SI from the ER to the Golgi. The characteristics of this motif are three phenylalanine residues that upon substitution by alanine generate the temperature-sensitive SIQ1098P phenotype. This mutant protein undergoes transport arrest in the ERGIC and cis-Golgi compartments and acquires correct folding and functional activity at reduced temperatures as a consequence of cycles of anterograde and retrograde transport between the ER and cis-Golgi. Other amino acid residues in this motif are not significant in the context of phenotype II. We propose that the phenylalanine cluster is required for shielding a folding determinant in the extracellular domain of SI; substitution of a Q by a P at residue 1098 of sucrase disrupts this determinant and elicits retention of SIQ1098P in ERGIC and cis-Golgi in phenotype II of CSID.
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Affiliation(s)
- Marcus J Pröpsting
- Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Germany
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