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Kramer L, Sarkar A, Foderaro T, Markley AL, Lee J, Edstrom H, Sharma S, Gill E, Traylor MJ, Fox JM. Genetically Encoded Detection of Biosynthetic Protease Inhibitors. ACS Synth Biol 2023; 12:83-94. [PMID: 36574400 PMCID: PMC10072156 DOI: 10.1021/acssynbio.2c00384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Proteases are an important class of drug targets that continue to drive inhibitor discovery. These enzymes are prone to resistance mutations, yet their promise for treating viral diseases and other disorders continues to grow. This study develops a general approach for detecting microbially synthesized protease inhibitors and uses it to screen terpenoid pathways for inhibitory compounds. The detection scheme relies on a bacterial two-hybrid (B2H) system that links protease inactivation to the transcription of a swappable reporter gene. This system, which can accomodate multiple biochemical outputs (i.e., luminescence and antibiotic resistance), permitted the facile incorporation of four disease-relevant proteases. A B2H designed to detect the inactivation of the main protease of severe acute respiratory syndrome coronavirus 2 enabled the identification of a terpenoid inhibitor of modest potency. An analysis of multiple pathways that make this terpenoid, however, suggested that its production was necessary but not sufficient to confer a survival advantage in growth-coupled assays. This finding highlights an important challenge associated with the use of genetic selection to search for inhibitors─notably, the influence of pathway toxicity─and underlines the value of including multiple pathways with overlapping product profiles in pathway screens. This study provides a detailed experimental framework for using microbes to screen libraries of biosynthetic pathways for targeted protease inhibitors.
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Affiliation(s)
- Levi Kramer
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
| | - Ankur Sarkar
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
| | - Tom Foderaro
- Think Bioscience, Inc., 1945 Colorado Avenue, Boulder, Colorado80309, United States
| | - Andrew L Markley
- Think Bioscience, Inc., 1945 Colorado Avenue, Boulder, Colorado80309, United States
| | - Jessica Lee
- Think Bioscience, Inc., 1945 Colorado Avenue, Boulder, Colorado80309, United States
| | - Hannah Edstrom
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
| | - Shajesh Sharma
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
| | - Eden Gill
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
| | - Matthew J Traylor
- Think Bioscience, Inc., 1945 Colorado Avenue, Boulder, Colorado80309, United States
| | - Jerome M Fox
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, 3415 Colorado Avenue, Boulder, Colorado80303, United States
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Sandomenico A, Caporale A, Doti N, Cross S, Cruciani G, Chambery A, De Falco S, Ruvo M. Synthetic Peptide Libraries: From Random Mixtures to In Vivo Testing. Curr Med Chem 2020; 27:997-1016. [PMID: 30009695 DOI: 10.2174/0929867325666180716110833] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 06/22/2018] [Accepted: 06/29/2018] [Indexed: 01/13/2023]
Abstract
Combinatorially generated molecular repertoires have been largely used to identify novel bioactive compounds. Ever more sophisticated technological solutions have been proposed to simplify and speed up such process, expanding the chemical diversity space and increasing the prospect to select new molecular entities with specific and potent activities against targets of therapeutic relevance. In this context, random mixtures of oligomeric peptides were originally used and since 25 years they represent a continuous source of bioactive molecules with potencies ranging from the sub-nM to microM concentration. Synthetic peptide libraries are still employed as starting "synthetic broths" of structurally and chemically diversified molecular fragments from which lead compounds can be extracted and further modified. Thousands of studies have been reported describing the application of combinatorial mixtures of synthetic peptides with different complexity and engrafted on diverse structural scaffolds for the identification of new compounds which have been further developed and also tested in in vivo models of relevant diseases. We briefly review some of the most used methodologies for library preparation and screening and the most recent case studies appeared in the literature where compounds have reached at least in vivo testing in animal or similar models. Recent technological advancements in biotechnology, engineering and computer science have suggested new options to facilitate the discovery of new bioactive peptides. In this instance, we anticipate here a new approach for the design of simple but focused tripeptide libraries against druggable cavities of therapeutic targets and its complementation with existing approaches.
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Affiliation(s)
- Annamaria Sandomenico
- Istituto di Biostrutture e Bioimmagini del CNR and CIRPeB, Universita Federico II di Napoli, via Mezzocannone, 16, 80134 Napoli, Italy
| | - Andrea Caporale
- Istituto di Biostrutture e Bioimmagini del CNR and CIRPeB, Universita Federico II di Napoli, via Mezzocannone, 16, 80134 Napoli, Italy
| | - Nunzianna Doti
- Istituto di Biostrutture e Bioimmagini del CNR and CIRPeB, Universita Federico II di Napoli, via Mezzocannone, 16, 80134 Napoli, Italy
| | - Simon Cross
- Molecular Discovery Ltd, Unit 501 Centennial Park, Centennial Avenue Elstree, Borehamwood, Hertfordshire WD6 3FG, United Kingdom
| | - Gabriele Cruciani
- Molecular Discovery Ltd, Unit 501 Centennial Park, Centennial Avenue Elstree, Borehamwood, Hertfordshire WD6 3FG, United Kingdom.,Dipartimento di Chimica, Biologia e Biotecnologia, Via Elce di Sotto 8, 06123 Perugia, Italy
| | - Angela Chambery
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "Luigi Vanvitelli", via Vivaldi, 43, 81100 Caserta, Italy
| | - Sandro De Falco
- Istituto di Genetica e Biofisica del CNR, via Pietro Castellino, 111, 80131, Napoli, Italy
| | - Menotti Ruvo
- Istituto di Biostrutture e Bioimmagini del CNR and CIRPeB, Universita Federico II di Napoli, via Mezzocannone, 16, 80134 Napoli, Italy
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3
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Choi JS, Joo SH. Recent Trends in Cyclic Peptides as Therapeutic Agents and Biochemical Tools. Biomol Ther (Seoul) 2020; 28:18-24. [PMID: 31597413 PMCID: PMC6939695 DOI: 10.4062/biomolther.2019.082] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/09/2019] [Accepted: 08/12/2019] [Indexed: 12/26/2022] Open
Abstract
Notable progress has been made in the therapeutic and research applications of cyclic peptides since our previous review. New drugs based on cyclic peptides are entering the market, such as plecanatide, a cyclic peptide approved by the United States Food and Drug Administration in 2017 for the treatment of chronic idiopathic constipation. In this review, we discuss recent developments in stapled peptides, prepared with the use of chemical linkers, and bicyclic/tricyclic peptides with more than two rings. These have widespread applications for clinical and research purposes: imaging, diagnostics, improvement of oral absorption, enzyme inhibition, development of receptor agonist/antagonist, and the modulation of protein-protein interaction or protein-RNA interaction. Many cyclic peptides are expected to emerge as therapeutics and biochemical tools.
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Affiliation(s)
- Joon-Seok Choi
- College of Pharmacy, Daegu Catholic University, Gyeongsan 38430, Republic of Korea
| | - Sang Hoon Joo
- College of Pharmacy, Daegu Catholic University, Gyeongsan 38430, Republic of Korea
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4
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Chittepu VCSR, Kalhotra P, Osorio-Gallardo T, Jiménez-Martínez C, Torre RRRDL, Gallardo-Velazquez T, Osorio-Revilla G. New Molecular Insights into the Inhibition of Dipeptidyl Peptidase-4 by Natural Cyclic Peptide Oxytocin. Molecules 2019; 24:E3887. [PMID: 31661941 PMCID: PMC6864445 DOI: 10.3390/molecules24213887] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/23/2019] [Accepted: 10/23/2019] [Indexed: 11/21/2022] Open
Abstract
Protease inhibition has led to treating many diseases and has been successful in producing many commercial drugs by pharmaceutical companies. Among many proteases, serine protease has been attractive in treating metabolic disorder diabetes mellitus (DM). Gliptins have been proven to inhibit dipeptidyl peptidase-4 (DPP4), a serine protease, and are an emerging therapeutic drug target to reduce blood glucose levels, but until now there is no natural cyclic peptide proven to inhibit serine protease DPP4. This study demonstrates the potential mechanism of natural cyclic peptide oxytocin (OXT) as a DPP4 inhibitor. To achieve this, initially, activity atlas and field-based models of DPP4 inhibitors were utilized to predict the possible features of positive and negative electrostatic, hydrophobic, and activity shapes of DPP4 inhibition. Oxytocin binding mode, flexibility, and interacting residues were studied using molecular docking simulations studies. 3D-RISM calculations studies revealed that the stability of water molecules at the binding site are favorable. Finally, an experimental study using fluorescence assay revealed OXT inhibits DPP4 in a concentration-dependent manner in a significant way (p < 0.05) and possess IC50 of 110.7 nM. These new findings significantly expand the pharmaceutical application of cyclic peptides, and in specific OXT, and implicate further optimization of OXT inhibition capacity to understand the effect of DPP4 inhibition. This work highlights the development of natural cyclic peptides as future therapeutic peptides to reduce glucose levels and treat diabetes mellitus.
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Affiliation(s)
- Veera C S R Chittepu
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Av. Wilfrido Massieu S/N, Col. Unidad Profesional Adolfo López Mateos, Zacatenco, Ciudad de Mexico 07738, Mexico.
| | - Poonam Kalhotra
- Departamento de Biofísica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Col. Santo Tomás, CP. Ciudad de Mexico 11340, Mexico.
| | - Tzayhri Osorio-Gallardo
- Departamento de Microbiologia e Immunologia, Facultad de Medicina Veterinaria Y Zootecnia, Universidad Nacional Autonoma de Mexico, Av. Universidad #3000, Delegacion Coyoacan, Col. Ciudad Universitaria, Ciudad de Mexico 04510, Mexico.
| | - Cristian Jiménez-Martínez
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Av. Wilfrido Massieu S/N, Col. Unidad Profesional Adolfo López Mateos, Zacatenco, Ciudad de Mexico 07738, Mexico.
| | - Raúl René Robles-de la Torre
- Centro de Investigación en Biotecnología Aplicada CIBA, Instituto Politécnico Nacional, Carretera Estatal, Tecuexcomac-Tepetitla, Km 1.5, CP. Tlaxcala 90700, Mexico.
| | - Tzayhri Gallardo-Velazquez
- Departamento de Biofísica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Col. Santo Tomás, CP. Ciudad de Mexico 11340, Mexico.
| | - Guillermo Osorio-Revilla
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Av. Wilfrido Massieu S/N, Col. Unidad Profesional Adolfo López Mateos, Zacatenco, Ciudad de Mexico 07738, Mexico.
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5
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Cyclic Peptides: Promising Scaffolds for Biopharmaceuticals. Genes (Basel) 2018; 9:genes9110557. [PMID: 30453533 PMCID: PMC6267108 DOI: 10.3390/genes9110557] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/08/2018] [Accepted: 11/08/2018] [Indexed: 12/31/2022] Open
Abstract
To date, small molecules and macromolecules, including antibodies, have been the most pursued substances in drug screening and development efforts. Despite numerous favorable features as a drug, these molecules still have limitations and are not complementary in many regards. Recently, peptide-based chemical structures that lie between these two categories in terms of both structural and functional properties have gained increasing attention as potential alternatives. In particular, peptides in a circular form provide a promising scaffold for the development of a novel drug class owing to their adjustable and expandable ability to bind a wide range of target molecules. In this review, we discuss recent progress in methodologies for peptide cyclization and screening and use of bioactive cyclic peptides in various applications.
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Ye B, Shen W, Shi M, Zhang Y, Xu C, Zhao Z. Intein-mediated backbone cyclization of entolimod confers enhanced radioprotective activity in mouse models. PeerJ 2018; 6:e5043. [PMID: 29938138 PMCID: PMC6011820 DOI: 10.7717/peerj.5043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/31/2018] [Indexed: 12/03/2022] Open
Abstract
Background Entolimod is a Salmonella enterica flagellin derivate. Previous work has demonstrated that entolimod effectively protects mice and non-human primates from ionizing radiation. However, it caused a “flu-like” syndrome after radioprotective and anticancer clinical application, indicating some type of immunogenicity and toxicity. Cyclization is commonly used to improve the in vivo stability and activity of peptides and proteins. Methods We designed and constructed cyclic entolimod using split Nostoc punctiforme DnaE intein with almost 100% cyclization efficiency. We adopted different strategies to purify the linear and circular entolimod due to their different topologies. Both of linear and circular entolimod were first purified by Ni-chelating affinity chromatography, and then the linear and circular entolimod were purified by size-exclusion and ion-exchange chromatography, respectively. Results The circular entolimod showed significantly increased both the in vitro NF-κB signaling and in vivo radioprotective activity in mice. Conclusion Our data indicates that circular entolimod might be a good candidate for further clinical investigation.
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Affiliation(s)
- Bingyu Ye
- College of Life Science, Henan Normal University, Xinxiang, China.,State Key Laboratory Cultivation Base for Cell Differentiation Regulation, College of Life Science, Henan Normal University, Xinxiang, China.,Beijing Institute of Biotechnology, Beijing, China
| | - Wenlong Shen
- Beijing Institute of Biotechnology, Beijing, China
| | - Minglei Shi
- Beijing Institute of Biotechnology, Beijing, China
| | - Yan Zhang
- Beijing Institute of Biotechnology, Beijing, China
| | - Cunshuan Xu
- College of Life Science, Henan Normal University, Xinxiang, China.,State Key Laboratory Cultivation Base for Cell Differentiation Regulation, College of Life Science, Henan Normal University, Xinxiang, China
| | - Zhihu Zhao
- Beijing Institute of Biotechnology, Beijing, China
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7
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Tavassoli A. SICLOPPS cyclic peptide libraries in drug discovery. Curr Opin Chem Biol 2017; 38:30-35. [PMID: 28258013 DOI: 10.1016/j.cbpa.2017.02.016] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/06/2017] [Accepted: 02/16/2017] [Indexed: 01/08/2023]
Abstract
Cyclic peptide libraries have demonstrated significant potential when employed against challenging targets such as protein-protein interactions. While a variety of methods for library generation exist, genetically encoded libraries hold several advantages over their chemically synthesized counterparts; they are more readily accessible and allow straightforward hit deconvolution. One method for the intracellular generation of such libraries is split-intein circular ligation of peptides and proteins (SICLOPPS). Here we detail and discuss the deployment of SICLOPPS libraries for the identification of cyclic peptide inhibitors of a variety of targets.
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Affiliation(s)
- Ali Tavassoli
- Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom.
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9
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Abstract
The DNA of Escherichia coli contains 19,120 6-methyladenines and 12,045 5-methylcytosines in addition to the four regular bases, and these are formed by the postreplicative action of three DNA methyltransferases. The majority of the methylated bases are formed by the Dam and Dcm methyltransferases encoded by the dam (DNA adenine methyltransferase) and dcm (DNA cytosine methyltransferase) genes. Although not essential, Dam methylation is important for strand discrimination during the repair of replication errors, controlling the frequency of initiation of chromosome replication at oriC, and the regulation of transcription initiation at promoters containing GATC sequences. In contrast, there is no known function for Dcm methylation, although Dcm recognition sites constitute sequence motifs for Very Short Patch repair of T/G base mismatches. In certain bacteria (e.g., Vibrio cholerae, Caulobacter crescentus) adenine methylation is essential, and, in C. crescentus, it is important for temporal gene expression, which, in turn, is required for coordinating chromosome initiation, replication, and division. In practical terms, Dam and Dcm methylation can inhibit restriction enzyme cleavage, decrease transformation frequency in certain bacteria, and decrease the stability of short direct repeats and are necessary for site-directed mutagenesis and to probe eukaryotic structure and function.
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10
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Frost JR, Jacob NT, Papa LJ, Owens AE, Fasan R. Ribosomal Synthesis of Macrocyclic Peptides in Vitro and in Vivo Mediated by Genetically Encoded Aminothiol Unnatural Amino Acids. ACS Chem Biol 2015; 10:1805-16. [PMID: 25933125 DOI: 10.1021/acschembio.5b00119] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A versatile method for orchestrating the formation of side chain-to-tail cyclic peptides from ribosomally derived polypeptide precursors is reported. Upon ribosomal incorporation into intein-containing precursor proteins, designer unnatural amino acids bearing side chain 1,3- or 1,2-aminothiol functionalities are able to promote the cyclization of a downstream target peptide sequence via a C-terminal ligation/ring contraction mechanism. Using this approach, peptide macrocycles of variable size and composition could be generated in a pH-triggered manner in vitro or directly in living bacterial cells. This methodology furnishes a new platform for the creation and screening of genetically encoded libraries of conformationally constrained peptides. This strategy was applied to identify and isolate a low-micromolar streptavidin binder (KD = 1.1 μM) from a library of cyclic peptides produced in Escherichia coli, thereby illustrating its potential toward aiding the discovery of functional peptide macrocycles.
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Affiliation(s)
- John R. Frost
- Department of Chemistry, University of Rochester, Hutchinson Hall, Rochester, New York 14627, United States
| | - Nicholas T. Jacob
- Department of Chemistry, University of Rochester, Hutchinson Hall, Rochester, New York 14627, United States
| | - Louis J. Papa
- Department of Chemistry, University of Rochester, Hutchinson Hall, Rochester, New York 14627, United States
| | - Andrew E. Owens
- Department of Chemistry, University of Rochester, Hutchinson Hall, Rochester, New York 14627, United States
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, Hutchinson Hall, Rochester, New York 14627, United States
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Foster AD, Ingram JD, Leitch EK, Lennard KR, Osher EL, Tavassoli A. Methods for the Creation of Cyclic Peptide Libraries for Use in Lead Discovery. ACTA ACUST UNITED AC 2015; 20:563-76. [DOI: 10.1177/1087057114566803] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/11/2014] [Indexed: 12/23/2022]
Abstract
The identification of initial hits is a crucial stage in the drug discovery process. Although many projects adopt high-throughput screening of small-molecule libraries at this stage, there is significant potential for screening libraries of macromolecules created using chemical biology approaches. Not only can the production of the library be directly interfaced with a cell-based assay, but these libraries also require significantly fewer resources to generate and maintain. In this context, cyclic peptides are increasingly viewed as ideal scaffolds and have proven capability against challenging targets such as protein-protein interactions. Here we discuss a range of methods used for the creation of cyclic peptide libraries and detail examples of their successful implementation.
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Affiliation(s)
| | | | | | | | | | - Ali Tavassoli
- Chemistry, University of Southampton, Southampton, UK
- Cancer Sciences, University of Southampton, Southampton, UK
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12
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Identification of inhibitors of a bacterial sigma factor using a new high-throughput screening assay. Antimicrob Agents Chemother 2014; 59:193-205. [PMID: 25331704 DOI: 10.1128/aac.03979-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Gram-negative bacteria are formidable pathogens because their cell envelope presents an adaptable barrier to environmental and host-mediated challenges. The stress response pathway controlled by the alternative sigma factor σ(E) is critical for maintenance of the cell envelope. Because σ(E) is required for the virulence or viability of several Gram-negative pathogens, it might be a useful target for antibiotic development. To determine if small molecules can inhibit the σ(E) pathway, and to permit high-throughput screening for antibiotic lead compounds, a σ(E) activity assay that is compatible with high-throughput screening was developed and validated. The screen employs a biological assay with positive readout. An Escherichia coli strain was engineered to express yellow fluorescent protein (YFP) under negative regulation by the σ(E) pathway, such that inhibitors of the pathway increase the production of YFP. To validate the screen, the reporter strain was used to identify σ(E) pathway inhibitors from a library of cyclic peptides. Biochemical characterization of one of the inhibitory cyclic peptides showed that it binds σ(E), inhibits RNA polymerase holoenzyme formation, and inhibits σ(E)-dependent transcription in vitro. These results demonstrate that alternative sigma factors can be inhibited by small molecules and enable high-throughput screening for inhibitors of the σ(E) pathway.
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13
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Lennard KR, Tavassoli A. Peptides Come Round: Using SICLOPPS Libraries for Early Stage Drug Discovery. Chemistry 2014; 20:10608-14. [DOI: 10.1002/chem.201403117] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Indexed: 11/06/2022]
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14
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Lee MM, Fekner T, Lu J, Heater BS, Behrman EJ, Zhang L, Hsu PH, Chan MK. Pyrrolysine-Inspired Protein Cyclization. Chembiochem 2014; 15:1769-72. [DOI: 10.1002/cbic.201402129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Indexed: 11/05/2022]
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15
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Cell-based assay to identify inhibitors of the Hfq-sRNA regulatory pathway. Antimicrob Agents Chemother 2014; 58:5500-9. [PMID: 25001303 DOI: 10.1128/aac.03311-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Noncoding small RNAs (sRNAs) act in conjunction with the RNA chaperone Hfq to regulate gene expression in bacteria. Because Hfq is required for virulence in several bacterial pathogens, the Hfq-sRNA system is an attractive target for antibiotic development. A reporter strain in which the expression of yellow fluorescent protein (YFP) is controlled by Hfq-sRNA was engineered to identify inhibitors of this system. A reporter that is targeted by Hfq in conjunction with the RybB sRNA was used in a genetic screen to identify inhibitors from a library of cyclic peptides produced in Escherichia coli using split-intein circular ligation of peptides and proteins (SICLOPPS), an intein-based technology. One cyclic peptide identified in this screen, RI20, inhibited Hfq-mediated repression of gene expression in conjunction with both RybB and an unrelated sRNA, MicF. Gel mobility shift assays showed that RI20 inhibited binding of Hfq to RybB and MicF with similar Ki values. These data suggest that RI20 inhibits Hfq activity by blocking interactions with sRNAs and provide a paradigm for inhibiting virulence genes in Gram-negative pathogens.
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16
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Joo SH. Cyclic peptides as therapeutic agents and biochemical tools. Biomol Ther (Seoul) 2014; 20:19-26. [PMID: 24116270 PMCID: PMC3792197 DOI: 10.4062/biomolther.2012.20.1.019] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/10/2011] [Accepted: 10/28/2011] [Indexed: 01/08/2023] Open
Abstract
There are many cyclic peptides with diverse biological activities, such as antibacterial activity, immunosuppressive activity, and anti-tumor activity, and so on. Encouraged by natural cyclic peptides with biological activity, efforts have been made to develop cyclic peptides with both genetic and synthetic methods. The genetic methods include phage display, intein-based cyclic peptides, and mRNA display. The synthetic methods involve individual synthesis, parallel synthesis, as well as split-and-pool synthesis. Recent development of cyclic peptide library based on split-and-pool synthesis allows on-bead screening, in-solution screening, and microarray screening of cyclic peptides for biological activity. Cyclic peptides will be useful as receptor agonist/antagonist, RNA binding molecule, enzyme inhibitor and so on, and more cyclic peptides will emerge as therapeutic agents and biochemical tools.
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Affiliation(s)
- Sang Hoon Joo
- Laboratory of Biochemistry, College of Pharmacy, Catholic University of Daegu, Gyeongsan 712-702, Republic of Korea
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17
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Abstract
Macrocyclic peptides are an emerging class of therapeutics that can modulate protein-protein interactions. In contrast to the heavily automated high-throughput screening systems traditionally used for the identification of chemically synthesized small-molecule drugs, peptide-based macrocycles can be synthesized by ribosomal translation and identified using in vitro selection techniques, allowing for extremely rapid (hours to days) screening of compound libraries comprising more than 10(13) different species. Furthermore, chemical modification of translated peptides and engineering of the genetic code have greatly expanded the structural diversity of the available peptide libraries. In this review, we discuss the use of these technologies for the identification of bioactive macrocyclic peptides, emphasizing recent developments.
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Affiliation(s)
- Toby Passioura
- Department of Chemistry, Graduate School of Science, University of Tokyo, Tokyo 113-0033, Japan; , , ,
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18
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Barreto K, Geyer CR. Screening combinatorial libraries of cyclic peptides using the yeast two-hybrid assay. Methods Mol Biol 2014; 1163:273-309. [PMID: 24841315 DOI: 10.1007/978-1-4939-0799-1_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Peptides are useful reagents for reverse analysis of protein function in a variety of organisms, as they have a dominant mode of action that can inhibit protein interactions or activities. Further, peptides are important tools for validating proteins as therapeutic targets, for determining structure/activity relationships, and for designing small molecules. Genetic selection strategies have been developed for screening combinatorial peptide libraries to rapidly isolate peptides that interact with a given target. In genetic selections and biological assays, linear peptides are not very stable and are rapidly degraded. In contrast, cyclic peptides are more stable and bind with higher affinity. Genetic selections of cyclic peptides are difficult as they are not compatible with most selection technologies. Thus, there has been limited number of applications that use cyclic peptides for the reverse analysis of protein function.Here, we describe a protocol to isolate cyclic peptides that bind proteins in the yeast two-hybrid assay. Cyclic peptides used in the yeast two-hybrid assay are referred to as "lariat" peptides. Lariat peptides are made by blocking the intein-producing cyclic peptide reaction at an intermediate step. They consist of a lactone cyclic peptide or "noose" region connected by an amide bond to a transcription activation domain. Combinatorial libraries of >10(7) lariat peptides can be screened using the yeast two-hybrid assay to isolate lariat peptides for studying the function or validating the therapeutic potential of protein targets.
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Affiliation(s)
- Kris Barreto
- Department of Biochemistry, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, Canada, S7N 5E5
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Abstract
Inteins are auto-processing domains found in organisms from all domains of life. These proteins carry out a process known as protein splicing, which is a multi-step biochemical reaction comprised of both the cleavage and formation of peptide bonds. While the endogenous substrates of protein splicing are specific essential proteins found in intein-containing host organisms, inteins are also functional in exogenous contexts and can be used to chemically manipulate virtually any polypeptide backbone. Given this, protein chemists have exploited various facets of intein reactivity to modify proteins in myriad ways for both basic biological research as well as potential therapeutic applications. Here, we review the intein field, first focusing on the biological context and phylogenetic diversity of inteins, followed by a description of intein structure and biochemical function. Finally, we discuss prevalent inteinbased technologies, focusing on their applications in chemical biology, followed by persistent caveats of intein chemistry and approaches to alleviate these shortcomings. The findings summarized herein describe two and a half decades of research, leading from a biochemical curiosity to the development of powerful protein engineering tools.
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Affiliation(s)
- Neel H Shah
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, NJ 08544, United States
| | - Tom W Muir
- Department of Chemistry, Princeton University, Frick Laboratory, Princeton, NJ 08544, United States
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20
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Frost JR, Smith JM, Fasan R. Design, synthesis, and diversification of ribosomally derived peptide macrocycles. Curr Opin Struct Biol 2013; 23:571-80. [PMID: 23856642 DOI: 10.1016/j.sbi.2013.06.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/19/2013] [Accepted: 06/20/2013] [Indexed: 10/26/2022]
Abstract
Ring topologies are widespread structural motifs among biologically active peptides found in nature. The recurrence of this motif is linked to the inherent advantages resulting from backbone cyclization, which include increased resistance against proteolytic degradation, improved cell permeability, and tighter and more specific interaction with the respective biomolecular target. Inspired by these natural product topologies, a number of groups have recently focused on developing methodologies that hinge upon the chemical elaboration of ribosomally derived polypeptides toward the synthesis and diversification of macrocyclic peptide structures. In this review, we highlight recent advances in this emerging new area and discuss the opportunities created by these methods toward the discovery of new functional entities.
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Affiliation(s)
- John R Frost
- Department of Chemistry, University of Rochester, Rochester, NY 14627, USA
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21
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Smith JM, Frost JR, Fasan R. Emerging strategies to access peptide macrocycles from genetically encoded polypeptides. J Org Chem 2013; 78:3525-31. [PMID: 23517465 DOI: 10.1021/jo400119s] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Macrocyclic peptides have emerged as attractive molecular scaffolds for the development of chemical probes and therapeutics. In this synopsis, we highlight contemporary strategies to access peptide macrocycles from ribosomally produced polypeptides. Challenges that have been tackled in this area involve orchestrating the desired macrocyclization process in the presence of unprotected polypeptide precursors and expanding the functional space encompassed by these molecules beyond that of canonical amino acid structures. Applications of these methodologies for the discovery of bioactive molecules are also discussed.
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Affiliation(s)
- Jessica M Smith
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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22
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Hobley G, McKelvie JC, Harmer JE, Howe J, Oyston PC, Roach PL. Development of rationally designed DNA N6 adenine methyltransferase inhibitors. Bioorg Med Chem Lett 2012; 22:3079-82. [DOI: 10.1016/j.bmcl.2012.03.072] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 03/16/2012] [Accepted: 03/19/2012] [Indexed: 01/12/2023]
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23
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Bowers AA. Biochemical and biosynthetic preparation of natural product-like cyclic peptide libraries. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20068f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Natural product gene clusters are increasingly being used to compliment biochemical methods for production of cyclic peptide libraries.
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Affiliation(s)
- Albert A. Bowers
- Purdue University
- Dept. of Medicinal Chemistry and Molecular Pharmacology
- West Lafayette
- USA
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24
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Abstract
Split inteins carry out a naturally occurring process known as protein trans-splicing, where two protein fragments bind to form a catalytically competent enzyme, then catalyze their own excision and the ligation of their flanking sequences. In the past thirteen years since their discovery, chemists and biologists have utilized split inteins in exogenous contexts for a number of biotechnological applications centered around the formation of native peptide bonds. While many protein trans-splicing technologies have emerged and flourished in recent years, several factors still limit their wide-spread practical use. Here, we discuss the development, applications, and limitations of split intein-based technologies and propose that further advancement in this field will require a more fundamental understanding of split intein structure and function.
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Affiliation(s)
- Neel H Shah
- Department of Chemistry, Princeton University, 325 Frick Laboratory, Princeton, New Jersey 08544, USA, Telephone: 609-258-5778
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25
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Katoh T, Goto Y, Reza MS, Suga H. Ribosomal synthesis of backbone macrocyclic peptides. Chem Commun (Camb) 2011; 47:9946-58. [PMID: 21766105 DOI: 10.1039/c1cc12647d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A wealth of knowledge has been accumulated on ribosomal synthesis of macrocyclic peptides in the past decade. In nature, backbone cyclization of the translated linear peptides is generally catalyzed by specific enzymes, giving them peptidase resistance, thermodynamic stability and various other physiological activities. Due to these biochemical traits, backbone cyclic peptides have become an attractive resource for the discovery of drug leads. Recently, various new methodologies have also been established to generate man-made cyclic peptides. Here, we describe the biosynthetic mechanisms of naturally occurring backbone macrocyclic peptides focusing on cyclotides, sunflower trypsin inhibitors (SFTIs) and cyanobactins as well as several new emerging methodologies, such as sortase mediated ligation, protein splicing method and genetic code reprogramming.
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Affiliation(s)
- Takayuki Katoh
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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26
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Abstract
We report a bacterial system for the evolution of cyclic peptides that makes use of an expanded set of amino acid building blocks. Orthogonal aminoacyl-tRNA synthetase/tRNA(CUA) pairs, together with a split intein system were used to biosynthesize a library of ribosomal peptides containing amino acids with unique structures and reactivities. This peptide library was subsequently used to evolve an inhibitor of HIV protease using a selection based on cellular viability. Two of three cyclic peptides isolated after two rounds of selection contained the keto amino acid p-benzoylphenylalanine (pBzF). The most potent peptide (G12: GIXVSL; X=pBzF) inhibited HIV protease through the formation of a covalent Schiff base adduct of the pBzF residue with the ε-amino group of Lys 14 on the protease. This result suggests that an expanded genetic code can confer an evolutionary advantage in response to selective pressure. Moreover, the combination of natural evolutionary processes with chemically biased building blocks provides another strategy for the generation of biologically active peptides using microbial systems.
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Khan SN, Kim A, Grubbs RH, Kwon YU. Ring-closing metathesis approaches for the solid-phase synthesis of cyclic peptoids. Org Lett 2011; 13:1582-5. [PMID: 21384884 DOI: 10.1021/ol200226z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyclic peptoids were efficiently synthesized on a solid phase in high yields utilizing ring-closing metathesis (RCM). This method should be a valuable tool for easy access to cyclic peptoid libraries and various cyclic compounds.
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Affiliation(s)
- Sharaf Nawaz Khan
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, South Korea
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28
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Deschuyteneer G, Garcia S, Michiels B, Baudoux B, Degand H, Morsomme P, Soumillion P. Intein-mediated cyclization of randomized peptides in the periplasm of Escherichia coli and their extracellular secretion. ACS Chem Biol 2010; 5:691-700. [PMID: 20527881 DOI: 10.1021/cb100072u] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Split-inteins can be used to generate backbone cyclized peptide as a source of new bioactive molecules. In this work we show that cysteine-mediated splicing can be performed in the oxidative environment of the periplasm of Escherichia coli. Cyclization of the TEM-1 beta-lactamase and of small randomized peptides was demonstrated using an artificially permuted version of the DnaB mini-intein from Synechocystis sp. PCC6803 strain fused to a signal sequence. For small peptides, a signal sequence that promotes cotranslational translocation had to be used. Efficient backbone cyclization was observed for more than 50% of combinatorial peptides featuring a fully randomized sequence inserted between a serine and glycine that are necessary for fast splicing. Furthermore, by coexpressing a mutant of the pIV outer membrane pore protein of fd bacteriophage, we showed that peptides can diffuse in the extracellular medium. These results open new routes for searching compounds acting on new targets such as exported and membrane proteins or pathogen microorganisms.
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Affiliation(s)
| | | | | | | | - Hervé Degand
- Physiologie Moléculaire, Institut des Sciences de la Vie, Université catholique de Louvain, Place Croix du Sud 4-5, B-1348 Louvain-la-Neuve, Belgium
| | - Pierre Morsomme
- Physiologie Moléculaire, Institut des Sciences de la Vie, Université catholique de Louvain, Place Croix du Sud 4-5, B-1348 Louvain-la-Neuve, Belgium
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Barreto K, Bharathikumar VM, Ricardo A, DeCoteau JF, Luo Y, Geyer CR. A genetic screen for isolating "lariat" Peptide inhibitors of protein function. ACTA ACUST UNITED AC 2010; 16:1148-57. [PMID: 19942138 DOI: 10.1016/j.chembiol.2009.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Revised: 09/30/2009] [Accepted: 10/19/2009] [Indexed: 10/20/2022]
Abstract
Functional genomic analyses provide information that allows hypotheses to be formulated on protein function. These hypotheses, however, need to be validated using reverse genetic approaches, which are difficult to perform on a large scale and in diploid organisms. We developed a genetic screen for isolating "lariat" peptides that function as trans dominant inhibitors of protein function. A lariat consists of a lactone-cyclized peptide with a covalently attached transcription activation domain, which allows combinatorial lariat libraries to be screened for protein interactions using the yeast two-hybrid assay. We isolated lariats against the bacterial repressor protein LexA. LexA regulates bacterial SOS response and LexA mutants that cannot undergo autoproteolysis make bacteria more sensitive to, and inhibit resistance against, cytotoxic reagents. We showed that an anti-LexA lariat blocked LexA autoproteolysis and potentiated the antimicrobial activity of mitomycin C.
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30
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Oyston PCF, Fox MA, Richards SJ, Clark GC. Novel peptide therapeutics for treatment of infections. J Med Microbiol 2009; 58:977-987. [DOI: 10.1099/jmm.0.011122-0] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
As antibiotic resistance increases worldwide, there is an increasing pressure to develop novel classes of antimicrobial compounds to fight infectious disease. Peptide therapeutics represent a novel class of therapeutic agents. Some, such as cationic antimicrobial peptides and peptidoglycan recognition proteins, have been identified from studies of innate immune effector mechanisms, while others are completely novel compounds generated in biological systems. Currently, only selected cationic antimicrobial peptides have been licensed, and only for topical applications. However, research using new approaches to identify novel antimicrobial peptide therapeutics, and new approaches to delivery and improving stability, will result in an increased range of peptide therapeutics available in the clinic for broader applications.
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Affiliation(s)
- P. C. F. Oyston
- Microbiology, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - M. A. Fox
- Microbiology, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - S. J. Richards
- Microbiology, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - G. C. Clark
- Microbiology, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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31
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Abstract
The DNA of Escherichia coli contains 19,120 6-methyladenines and 12,045 5-methylcytosines in addition to the four regular bases, and these are formed by the postreplicative action of three DNA methyltransferases. The majority of the methylated bases are formed by the Dam and Dcmmethyltransferases encoded by the dam (DNA adenine methyltransferase) and dcm (DNA cytosine methyltransferase) genes. Although not essential, Dam methylation is important for strand discrimination during repair of replication errors, controlling the frequency of initiation of chromosome replication at oriC, and regulation of transcription initiation at promoters containing GATC sequences. In contrast, there is no known function for Dcm methylation, although Dcm recognition sites constitute sequence motifs for Very Short Patch repair of T/G base mismatches. In certain bacteria (e.g., Vibrio cholera and Caulobactercrescentus) adenine methylation is essential, and in C.crescentus it is important for temporal gene expression which, in turn, is required for coordination of chromosome initiation, replication, and division. In practical terms, Dam and Dcm methylation can inhibit restriction enzyme cleavage,decrease transformation frequency in certain bacteria,and decrease the stability of short direct repeats andare necessary for site-directed mutagenesis and to probe eukaryotic structure and function.
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Zhou H, Purdy MM, Dahlquist FW, Reich NO. The Recognition Pathway for the DNA Cytosine Methyltransferase M.HhaI,. Biochemistry 2009; 48:7807-16. [DOI: 10.1021/bi900502g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Hongjun Zhou
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510
| | - Matthew M. Purdy
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510
| | - Frederick W. Dahlquist
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510
| | - Norbert O. Reich
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510
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33
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Coffin SR, Reich NO. Escherichia coli DNA adenine methyltransferase: the structural basis of processive catalysis and indirect read-out. J Biol Chem 2009; 284:18390-400. [PMID: 19419959 PMCID: PMC2709375 DOI: 10.1074/jbc.m109.005876] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 04/08/2009] [Indexed: 11/06/2022] Open
Abstract
We have investigated the structural basis of processive GATC methylation by the Escherichia coli DNA adenine methyltransferase, which is critical in chromosome replication and mismatch repair. We determined the contribution of the orthologically conserved phosphate interactions involving residues Arg(95), Asn(126), Asn(132), Arg(116), and Lys(139), which directly contact the DNA outside the cognate recognition site (GATC) to processive catalysis, and that of residue Arg(137), which is not conserved and contacts the DNA backbone within the GATC sequence. Alanine substitutions at the conserved positions have large impacts on processivity yet do not impact k(cat)/K(m)(DNA) or DNA affinity (K(D)(DNA)). However, these mutants cause large preferences for GATC sites varying in flanking sequences when considering the pre-steady state efficiency constant k(chem)/K(D)(DNA). These changes occur mainly at the level of the methylation rate constant, which results in the observed decreases in processive catalysis. Thus, processivity and catalytic efficiency (k(cat)/K(m)(DNA)) are uncoupled in these mutants. These results reveal that the binding energy involved in DNA recognition contributes to the assembly of the active site rather than tight binding. Furthermore, the conserved residues (Arg(95), Asn(126), Asn(132), and Arg(116)) repress the modulation of the response of the enzyme to flanking sequence effects. Processivity impacted mutants do not show substrate-induced dimerization as is observed for the wild type enzyme. This study describes the structural means by which an enzyme that does not completely enclose its substrate has evolved to achieve processive catalysis, and how interactions with DNA flanking the recognition site alter this processivity.
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Affiliation(s)
| | - Norbert O. Reich
- From the Department of Chemistry and Biochemistry and
- the Biomolecular Science and Engineering Program, University of California, Santa Barbara, California 93106-9510
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34
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Biochemie: Benkovic ausgezeichnet / Nano und Mikro: Preis für Whitesides / Anorganische Chemie: Hawthorne geehrt. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200902386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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Biochemistry: Benkovic Awarded / Nano and Micro: Prize for Whitesides / Inorganic Chemistry: Hawthorne Honored. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/anie.200902386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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