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Sahu S, Banerjee R, Pal D. Intrinsic proclivity of left-handed conformation in large Nest motif peptides inferred from molecular dynamics. J Biomol Struct Dyn 2023:1-10. [PMID: 37464873 DOI: 10.1080/07391102.2023.2236710] [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: 04/26/2023] [Accepted: 07/10/2023] [Indexed: 07/20/2023]
Abstract
The 'Nest' motif plays a functional role in protein owing to its ligand binding potential aided by geometric concavity. The presence of less favored left-handed conformation (L-state) in its structure makes this concavity possible and in shaping the native chemical environment amenable to stable binding interactions. To understand the persistent appearance of L-state torsion in the Nest motif, we analyzed 0.5μs Molecular Dynamics (MD) simulation trajectories of 35 six-residue peptides (out of a total of 50 large Nest sequences of ≥6 residues) identified in our previous study. Analysis of the MD trajectories of the individual peptides reveals initial L-state in 60% of the peptides persists for >40% of the trajectory. Further, Nests with different sequences appear to adopt a specific conformational state driven by the neighboring L-state residues. The sequences also possess short secondary structures and amino acid repeats, suggesting evolutionary conservation and the specific role of amino acids in locally predisposing the torsion angle to the L-state. These findings help us to understand how L-state conformation is an essential prerequisite in stabilizing the Nest motif and shed light on the sequence-structure-function paradigm in the rational design of peptides and peptidomimetics for therapeutics.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Subhankar Sahu
- Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, Haringhata, West Bengal, India
| | - Raja Banerjee
- Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, Haringhata, West Bengal, India
| | - Debnath Pal
- Department of Computational and Data Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
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2
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Pal D, Sahu S, Banerjee R. New facets of larger Nest motifs in proteins. Proteins 2020; 88:1413-1422. [PMID: 32519388 DOI: 10.1002/prot.25961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 06/06/2020] [Indexed: 11/07/2022]
Abstract
The Nest is a concave-shaped structural motif in proteins formed by consecutive enantiomeric left-handed (L) and right-handed (R) helical conformation of the backbone. This important motif subsumes many turn and helix capping structures and binds electron-rich ligands. Simple Nests are either RL or LR. Larger Nests (>2 residues long) may be RLR, LRL, RLRL, and so forth, being considered as composed of overlapping simple Nests. The larger Nests remain under-explored despite their widely known contributions to protein function. In our study, we address whether the recurrence of enantiomeric geometry in the larger Nests constrains the peptide backbone such that distinct compositional and conformational preferences are seen compared to simple Nests. Our analysis reveals the critical role of the L helical torsion angle in the formation of larger Nests. This can be observed through the higher propensity of residue or secondary structure combinations in LR and LRL backbone conformation in comparison to RL or RLR, although LR/LRL is considerably lower by occurrence. We also find that the most abundant doublets and triplets in Nests have a propensity for particular secondary structures, suggesting a strong sequence-structure relationship in the larger Nest. Overall, our analysis corroborates distinct features of simple and the larger Nests. Such insights would be helpful towards in-vitro design of peptides and peptidomimetic studies.
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Affiliation(s)
- Debnath Pal
- Department of Computational and Data Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Subhankar Sahu
- Department of Bioinformatics, Maulana Abul Kalam Azad University of Technology, Kolkata, West Bengal, India
| | - Raja Banerjee
- Department of Bioinformatics, Maulana Abul Kalam Azad University of Technology, Kolkata, West Bengal, India.,Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, Kolkata, West Bengal, India
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3
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Sheet T, Banerjee R. Design of a Peptide-Based Model Leads for Scavenging Anions. ACS OMEGA 2020; 5:9759-9767. [PMID: 32391463 PMCID: PMC7203709 DOI: 10.1021/acsomega.9b04180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
Among several peptide-based anion recognition motifs, the "CαNN" motif containing C-1 α, N0, and N+1 of three consecutive residues is unique in its mode of interaction. Having a spatial geometry of βαα or βαβ, this motif occurs in the N terminus of a helix and often found at the functional interface of a protein, mediating crucial biological significance upon interaction with anion(s). The interaction of anion(s) with chimeric peptide sequences containing the naturally occurring "CαNN" motif (CPS224Ac, CPS226, and CPS228) reported in our previous attempts strongly confirms that the information regarding the interaction is embedded within the local sequences of the motif segment. At these prevailing circumstances, an effort has been pursued to design novel scaffolds based on the "CαNN" motif for achieving better recognition of anion(s). Exploring the existing data set of the "CαNN" motif available in the FSSP database, four novel peptide-based scaffolds have been designed (DS1, DS2, DS3, and DS4), and preliminary screenings have been performed using computational approaches. Our initial work suggests that two (DS1 and DS3) out of the four scaffolds are potential candidates for better anion recognition. By employing biophysical characterization using both qualitative and quantitative measures, in this present study, we report the interaction of sulfate and phosphate ions with these two designed scaffolds, in which there is much better recognition of anions by these scaffolds than the natural sequences, justifying their logical engineering. Our observation strongly suggests that these designed scaffolds are better potential candidates than those of the naturally occurring "CαNN" motif in terms of anion recognition and could be utilized for the scavenging of anion(s) for different purposes.
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Affiliation(s)
- Tridip Sheet
- Department
of Bioinformatics, Maulana Abul Kalam Azad
University of Technology, West Bengal (Formerly Known as West Bengal
University of Technology), BF-142, Sector-1, Salt Lake, Kolkata 700064, India
| | - Raja Banerjee
- Department
of Bioinformatics, Maulana Abul Kalam Azad
University of Technology, West Bengal (Formerly Known as West Bengal
University of Technology), BF-142, Sector-1, Salt Lake, Kolkata 700064, India
- Department
of Biotechnology, Maulana Abul Kalam Azad
University of Technology, West Bengal (Formerly Known as West Bengal
University of Technology), BF-142, Sector-1, Salt Lake, Kolkata 700064, India
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4
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Sahu S, Sheet T, Banerjee R. Interaction landscape of a 'C αNN' motif with arsenate and arsenite: a potential peptide-based scavenger of arsenic. RSC Adv 2019; 9:1062-1074. [PMID: 35517606 PMCID: PMC9059529 DOI: 10.1039/c8ra08225a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 12/08/2018] [Indexed: 12/01/2022] Open
Abstract
Arsenic (As) is a toxic metalloid that has drawn immense attention from the scientific community recently due to its fatal effects through its unwanted occurrence in ground water around the globe. The presence of an excess amount of water soluble arsenate and/or arsenite salt (permissible limit 10 μg L-1 as recommended by the WHO) in water has been correlated with several human diseases. Although arsenate (HAsO4 2-) is a molecular analogue of phosphate (HPO4 2-), phosphate is indispensable for life, while arsenic and its salts are toxic. Therefore, it is worthwhile to focus on the removal of arsenic from water. Towards this end, the design of peptide-based scaffolds for the recognition of arsenate and arsenite would add a new dimension. Utilizing the stereochemical similarity between arsenate (HAsO4 2-) and phosphate (HPO4 2-), we successfully investigated the recognition of arsenate and arsenite with a naturally occurring novel phosphate binding 'CαNN' motif and its related designed analogues. Using computational as well as biophysical approaches, for the first time, we report here that a designed peptide-based scaffold based on the 'CαNN' motif can recognize anions of arsenic in a thermodynamically favorable manner in a context-free system. This peptide-based arsenic binding agent has the potential for future development as a scavenger of arsenic anions to obtain arsenic free water.
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Affiliation(s)
- Subhankar Sahu
- Department of Biotechnology and Head Department of Bioinformatics, Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology) BF-142, Salt Lake Kolkata 700064 West Bengal India
| | - Tridip Sheet
- Department of Biotechnology and Head Department of Bioinformatics, Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology) BF-142, Salt Lake Kolkata 700064 West Bengal India
| | - Raja Banerjee
- Department of Biotechnology and Head Department of Bioinformatics, Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology) BF-142, Salt Lake Kolkata 700064 West Bengal India
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5
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Patra P, Ghosh M, Banerjee R, Chakrabarti J. Quantum chemical studies on anion specificity of C αNN motif in functional proteins. J Comput Aided Mol Des 2018; 32:929-936. [PMID: 30182143 DOI: 10.1007/s10822-018-0157-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/29/2018] [Indexed: 10/28/2022]
Abstract
Anion binding CαNN motif is found in functionally important regions of protein structures. This motif based only on backbone atoms from three adjacent residues, recognizes free sulphate or phosphate ion as well as phosphate groups in nucleotides and in a variety of cofactors. The mode of anion recognition and microscopic picture of binding interaction remains unclear. Here we perform self-consistent quantum chemical calculations considering sulphate and phosphate bound CαNN motif fragments from crystal structures of functional proteins in order to figure out microscopic basis of anion recognition. Our calculations indicate that stability and preference of the anion in the motif depends on the sequence of the motif. The stabilization energy is larger in case of polar residue containing motif fragment. Nitrogen atom of the polar residue of motif mainly participates in the coordination at the lowest energy levels. Anion replacement decreases stabilization energy along with coordination between motif atoms and oxygen atoms of anion shifted to higher energies, suggesting preference of the motif residues to specific anion. Our analysis may be helpful to understand microscopic basis of interaction between proteins and ionic species.
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Affiliation(s)
- Piya Patra
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly known as WBUT), BF-142, Sector-I, Salt Lake, Kolkata, 700064, India.
| | - Mahua Ghosh
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Sector III, Block JD, Salt Lake, Kolkata, 700106, India
| | - Raja Banerjee
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly known as WBUT), BF-142, Sector-I, Salt Lake, Kolkata, 700064, India
| | - Jaydeb Chakrabarti
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Sector III, Block JD, Salt Lake, Kolkata, 700106, India. .,The Thematic Unit of Excellence on Computational Materials Science, S.N. Bose National Centre for Basic Sciences, Sector-III, Block JD, Salt Lake, Kolkata, 700106, India.
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6
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Patra P, Ghosh M, Banerjee R, Chakrabarti J. Anion induced conformational preference of C α NN motif residues in functional proteins. Proteins 2017; 85:2179-2190. [PMID: 28905427 DOI: 10.1002/prot.25382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/16/2017] [Accepted: 09/10/2017] [Indexed: 11/12/2022]
Abstract
Among different ligand binding motifs, anion binding Cα NN motif consisting of peptide backbone atoms of three consecutive residues are observed to be important for recognition of free anions, like sulphate or biphosphate and participate in different key functions. Here we study the interaction of sulphate and biphosphate with Cα NN motif present in different proteins. Instead of total protein, a peptide fragment has been studied keeping Cα NN motif flanked in between other residues. We use classical force field based molecular dynamics simulations to understand the stability of this motif. Our data indicate fluctuations in conformational preferences of the motif residues in absence of the anion. The anion gives stability to one of these conformations. However, the anion induced conformational preferences are highly sequence dependent and specific to the type of anion. In particular, the polar residues are more favourable compared to the other residues for recognising the anion.
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Affiliation(s)
- Piya Patra
- Maulana Abul Kalam Azad University of Technology, West Bengal, (Formerly known as WBUT), BF-142, Sector-I, Saltlake, Kolkata, 700 064, India
| | - Mahua Ghosh
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Sector III, Block JD, Salt Lake, Kolkata, 700106, India
| | - Raja Banerjee
- Maulana Abul Kalam Azad University of Technology, West Bengal, (Formerly known as WBUT), BF-142, Sector-I, Saltlake, Kolkata, 700 064, India
| | - Jaydeb Chakrabarti
- Department of Chemical, Biological and Macro-Molecular Sciences, S.N. Bose National Centre for Basic Sciences, Sector III, Block JD, Salt Lake, Kolkata, 700106, India.,The Thematic Unit of Excellence on Computational Materials Science, S. N. Bose National Centre for Basic Sciences, Sector-III, Block JD, Salt Lake, Kolkata, 700106, India
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7
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Banerjee R, Sheet T. Ratio of ellipticities between 192 and 208 nm (R 1 ): An effective electronic circular dichroism parameter for characterization of the helical components of proteins and peptides. Proteins 2017; 85:1975-1982. [PMID: 28707342 DOI: 10.1002/prot.25351] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/09/2017] [Accepted: 07/10/2017] [Indexed: 01/28/2023]
Abstract
Circular dichroism (CD) spectroscopy represents an important tool for characterization of the peptide and protein secondary structures that mainly arise from the conformational disposition of the peptide backbone in solution. In 1991 Manning and Woody proposed that, in addition to the signal intensity, the ratio between [θ]nπ* and [θ]ππ*ǁ ((R2 ) ≅ [θ]222 /[θ]208 ), along with [θ]ππ*⊥ and [θ]ππ*ǁ ((R1 ) ≅ [θ]192 /[θ]208 ), may be utilized towards identifying the peptide/protein conformation (especially 310 - and α-helices). However, till date the use of the ratiometric ellipticity component for helical structure analysis of peptides and proteins has not been reported. We studied a series of temperature dependent CD spectra of a thermally stable, model helical peptide and its related analogs in water as a function of added 2,2,2-trifluoroethanol (TFE) in order to explore their landscape of helicity. For the first time, we have experimentally shown here that the R1 parameter can characterize better the individual helices, while the other parameter R2 and the signal intensity do not always converge. We emphasize the use of the R1 ratio of ellipticities for helical characterization because of the common origin of these two bands (exciton splitting of the amide π→ π* transition in a helical polypeptide). This approach may become worthwhile and timely with the increasing accessibility of CD synchrotron sources.
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Affiliation(s)
- Raja Banerjee
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology), Salt Lake, Kolkata, 700064, West Bengal, India
| | - Tridip Sheet
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology), Salt Lake, Kolkata, 700064, West Bengal, India
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8
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Sheet T, Ghosh S, Pal D, Banerjee R. Computational design of model scaffold for anion recognition based on the 'C α NN' motif. Biopolymers 2017; 108. [PMID: 27428807 DOI: 10.1002/bip.22921] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/05/2016] [Accepted: 07/14/2016] [Indexed: 11/06/2022]
Abstract
The 'novel phosphate binding 'Cα NN' motif', consisting of three consecutive amino acid residues, usually occurs in the protein loop regions preceding a helix. Recent computational and complementary biophysical experiments on a series of chimeric peptides containing the naturally occurring 'Cα NN' motif at the N-terminus of a designed helix establishes that the motif segment recognizes the anion (sulfate and phosphate ions) through local interaction along with extension of the helical conformation which is thermodynamically favored even in a context-free, nonproteinaceous isolated system. However, the strength of the interaction depends on the amino acid sequence/conformation of the motif. Such a locally-mediated recognition of anions validates its intrinsic affinity towards anions and confirms that the affinity for recognition of anions is embedded within the 'local sequence' of the motif. Based on the knowledge gathered on the sequence/structural aspects of the naturally occurring 'Cα NN' segment, which provides the guideline for rationally engineering model scaffolds, we have modeled a series of templates and investigated their interactions with anions using computational approach. Two of these designed scaffolds show more efficient anion recognition than those of the naturally occurring 'Cα NN' motif which have been studied. This may provide an avenue in designing better anion receptors suitable for various biochemical applications.
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Affiliation(s)
- Tridip Sheet
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology), BF-142, Sector-1, Salt Lake, Kolkata, 700064, India
| | - Suvankar Ghosh
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology), BF-142, Sector-1, Salt Lake, Kolkata, 700064, India
| | - Debnath Pal
- Indian Institute of Science, Bangalore, 560012, India
| | - Raja Banerjee
- Maulana Abul Kalam Azad University of Technology, West Bengal (Formerly Known as West Bengal University of Technology), BF-142, Sector-1, Salt Lake, Kolkata, 700064, India
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9
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Langton MJ, Serpell CJ, Beer PD. Anion Recognition in Water: Recent Advances from a Supramolecular and Macromolecular Perspective. Angew Chem Int Ed Engl 2016; 55:1974-87. [PMID: 26612067 PMCID: PMC4755225 DOI: 10.1002/anie.201506589] [Citation(s) in RCA: 307] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Indexed: 12/22/2022]
Abstract
The recognition of anions in water remains a key challenge in modern supramolecular chemistry, and is essential if proposed applications in biological, medical, and environmental arenas that typically require aqueous conditions are to be achieved. However, synthetic anion receptors that operate in water have, in general, been the exception rather than the norm to date. Nevertheless, a significant step change towards routinely conducting anion recognition in water has been achieved in the past few years, and this Review highlights these approaches, with particular focus on controlling and using the hydrophobic effect, as well as more exotic interactions such as C-H hydrogen bonding and halogen bonding. We also look beyond the field of small-molecule recognition into the macromolecular domain, covering recent advances in anion recognition based on biomolecules, polymers, and nanoparticles.
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Affiliation(s)
- Matthew J Langton
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
| | - Christopher J Serpell
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK.
- School of Physical Sciences, Ingram Building, University of Kent, Canterbury, Kent, CT2 7NH, UK.
| | - Paul D Beer
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK.
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10
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Abstract
The ‘CαNN’ motif has an intrinsic affinity for the anions and can recognize anion through local interactions along with augmentation of the helical conformation at the motif segment.
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Affiliation(s)
- Tridip Sheet
- Maulana Abul Kalam Azad University of Technology (Formerly Known as West Bengal University of Technology)
- Kolkata – 700064
- India
| | - Raja Banerjee
- Maulana Abul Kalam Azad University of Technology (Formerly Known as West Bengal University of Technology)
- Kolkata – 700064
- India
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11
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Langton MJ, Serpell CJ, Beer PD. Anionenerkennung in Wasser: aktuelle Fortschritte aus supramolekularer und makromolarer Sicht. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201506589] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Matthew J. Langton
- Chemistry Research Laboratory; Department of Chemistry; University of Oxford; Mansfield Road Oxford OX1 3TA Vereinigtes Königreich
| | - Christopher J. Serpell
- Chemistry Research Laboratory; Department of Chemistry; University of Oxford; Mansfield Road Oxford OX1 3TA Vereinigtes Königreich
- School of Physical Sciences, Ingram Building; University of Kent; Canterbury Kent CT2 7NH Vereinigtes Königreich
| | - Paul D. Beer
- Chemistry Research Laboratory; Department of Chemistry; University of Oxford; Mansfield Road Oxford OX1 3TA Vereinigtes Königreich
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12
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Giuliano MW, Lin CY, Romney DK, Miller SJ, Anslyn EV. A Synergistic Combinatorial and Chiroptical Study of Peptide Catalysts for Asymmetric Baeyer-Villiger Oxidation. Adv Synth Catal 2015; 357:2301-2309. [PMID: 26543444 DOI: 10.1002/adsc.201500230] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We report an approach to the asymmetric Baeyer-Villiger oxidation utilizing bioinformatics-inspired combinatorial screening for catalyst discovery. Scaled-up validation of our on-bead efforts with a circular dichroism-based assay of alcohols derived from the products of solution-phase reactions established the absolute configuration of lactone products; this assay proved equivalent to HPLC in its ability to evaluate catalyst performance, but was far superior in its speed of analysis. Further solution-phase screening of a focused library suggested a mode of asymmetric induction that draws distinct parallels with the mechanism of Baeyer-Villiger monooxygenases.
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Affiliation(s)
- Michael W Giuliano
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States,
| | - Chung-Yon Lin
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States,
| | - David K Romney
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States,
| | - Scott J Miller
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States,
| | - Eric V Anslyn
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States,
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