1
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Ramezani Khorsand F, Hakimi Naeini S, Molakarimi M, Dehnavi E, Zeinoddini M, Sajedi RH. Surface display provides an efficient expression system for production of recombinant proteins and bacterial whole cell biosensor in E. coli. Anal Biochem 2024; 694:115599. [PMID: 38964699 DOI: 10.1016/j.ab.2024.115599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/14/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
A novel bacterial display vector based on Escherichia coli has been engineered for recombinant protein production and purification. Accordingly, a construct harboring the enhanced green fluorescent protein (EGFP) and the ice nucleation protein (INP) was designed to produce EGFP via the surface display in E. coli cells. The fusion EGFP-expressed cells were then investigated using fluorescence measurement, SDS- and native-PAGE before and after TEV protease digestion. The displayed EGFP was obtained with a recovery of 57.7 % as a single band on SDS-PAGE. Next, the efficiency of the cell surface display for mutant EGFP (EGFP S202H/Q204H) was examined in sensing copper ions. Under optimal conditions, a satisfactorily linear range for copper ions concentrations up to 10 nM with a detection limit of 0.073 nM was obtained for cell-displayed mutant EGFP (mEGFP). In the presence of bacterial cell lysates and purified mEGFP, response to copper was linear in the 2-10 nM and 0.1-2 μM concentration range, respectively, with a 1.3 nM and 0.14 μM limit of detection. The sensitivity of bacterial cell lysates and surface-displayed mEGFP in the detection of copper ions is higher than the purified mEGFP.
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Affiliation(s)
- Fereshteh Ramezani Khorsand
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran.
| | - Saghi Hakimi Naeini
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran.
| | - Maryam Molakarimi
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran.
| | - Ehsan Dehnavi
- Gene Transfer Pioneers (GTP) Research Group, Incubation Center of Pharmaceutical Technologies, Shahid Beheshti University of Medical Science, Tehran, Iran.
| | - Mehdi Zeinoddini
- Department of Bioscience and Biotechnology, Malek Ashtar University of Technology, Tehran, Iran.
| | - Reza H Sajedi
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115-154, Iran.
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2
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Ye Z, Fu L, Li S, Chen Z, Ouyang J, Shang X, Liu Y, Gao L, Wang Y. Synergistic collaboration between AMPs and non-direct antimicrobial cationic peptides. Nat Commun 2024; 15:7319. [PMID: 39183339 PMCID: PMC11345435 DOI: 10.1038/s41467-024-51730-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 08/14/2024] [Indexed: 08/27/2024] Open
Abstract
Non-direct antimicrobial cationic peptides (NDACPs) are components of the animal innate immune system. But their functions and association with antimicrobial peptides (AMPs) are incompletely understood. Here, we reveal a synergistic interaction between the AMP AW1 and the NDACP AW2, which are co-expressed in the frog Amolops wuyiensis. AW2 enhances the antibacterial activity of AW1 both in vitro and in vivo, while mitigating the development of bacterial resistance and eradicating biofilms. AW1 and AW2 synergistically damage bacterial membranes, facilitating cellular uptake and interaction of AW2 with the intracellular target bacterial genomic DNA. Simultaneously, they trigger the generation of ROS in bacteria, contributing to cell death upon reaching a threshold level. Moreover, we demonstrate that this synergistic antibacterial effect between AMPs and NDACPs is prevalent across diverse animal species. These findings unveil a robust and previously unknown correlation between AMPs and NDACPs as a widespread antibacterial immune defense strategy in animals.
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Affiliation(s)
- Zifan Ye
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Lei Fu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Shuangyu Li
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Ziying Chen
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Jianhong Ouyang
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Xinci Shang
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Yanli Liu
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Lianghui Gao
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China.
| | - Yipeng Wang
- Department of Biopharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China.
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China.
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3
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Ullrich S, Somathilake U, Shang M, Nitsche C. Phage-encoded bismuth bicycles enable instant access to targeted bioactive peptides. Commun Chem 2024; 7:143. [PMID: 38937646 PMCID: PMC11211329 DOI: 10.1038/s42004-024-01232-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 06/20/2024] [Indexed: 06/29/2024] Open
Abstract
Genetically encoded libraries play a crucial role in discovering structurally rigid, high-affinity macrocyclic peptide ligands for therapeutic applications. Bicyclic peptides with metal centres like bismuth were recently developed as a new type of constrained peptide with notable affinity, stability and membrane permeability. This study represents the genetic encoding of peptide-bismuth and peptide-arsenic bicycles in phage display. We introduce bismuth tripotassium dicitrate (gastrodenol) as a water-soluble bismuth(III) reagent for phage library modification and in situ bicyclic peptide preparation, eliminating the need for organic co-solvents. Additionally, we explore arsenic(III) as an alternative thiophilic element that is used analogously to our previously introduced bicyclic peptides with a bismuth core. The modification of phage libraries and peptides with these elements is instantaneous and entirely biocompatible, offering an advantage over conventional alkylation-based methods. In a pilot display screening campaign aimed at identifying ligands for the biotin-binding protein streptavidin, we demonstrate the enrichment of bicyclic peptides with dissociation constants two orders of magnitude lower than those of their linear counterparts, underscoring the impact of structural constraint on binding affinity.
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Affiliation(s)
- Sven Ullrich
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Upamali Somathilake
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Minghao Shang
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Christoph Nitsche
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.
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4
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Muts RM, den Boer MA, Bardoel BW, Aerts PC, de Haas CJC, Heck AJR, Rooijakkers SHM, Heesterbeek DAC. Artificial surface labelling of Escherichia coli with StrepTagII antigen to study how monoclonal antibodies drive complement-mediated killing. Sci Rep 2023; 13:18836. [PMID: 37914798 PMCID: PMC10620216 DOI: 10.1038/s41598-023-46026-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/26/2023] [Indexed: 11/03/2023] Open
Abstract
Antibodies play a key role in the immune defence against Gram-negative bacteria. After binding to bacterial surface antigens, IgG and IgM can activate the complement system and trigger formation of lytic membrane attack complex (MAC) pores. Molecular studies to compare functional activity of antibodies on bacteria are hampered by the limited availability of well-defined antibodies against bacterial surface antigens. Therefore, we genetically engineered E. coli by expressing the StrepTagII antigen into outer membrane protein X (OmpX) and validated that these engineered bacteria were recognised by anti-StrepTagII antibodies. We then combined this antigen-antibody system with a purified complement assay to avoid interference of serum components and directly compare MAC-mediated bacterial killing via IgG1 and pentameric IgM. While both IgG1 and IgM could induce MAC-mediated killing, we show that IgM has an increased capacity to induce complement-mediated killing of E. coli compared to IgG1. While Fc mutations that enhance IgG clustering after target binding could not improve MAC formation, mutations that cause formation of pre-assembled IgG hexamers enhanced the complement activating capacity of IgG1. Altogether, we here present a system to study antibody-dependent complement activation on E. coli and show IgM's enhanced capacity over IgG to induce complement-mediated lysis of E. coli.
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Affiliation(s)
- Remy M Muts
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Maurits A den Boer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomic Center, 3584 CH, Utrecht, The Netherlands
| | - Bart W Bardoel
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Piet C Aerts
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Carla J C de Haas
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomic Center, 3584 CH, Utrecht, The Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Dani A C Heesterbeek
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands.
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5
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Holt BA, Lim HS, Sivakumar A, Phuengkham H, Su M, Tuttle M, Xu Y, Liakakos H, Qiu P, Kwong GA. Embracing enzyme promiscuity with activity-based compressed biosensing. CELL REPORTS METHODS 2023; 3:100372. [PMID: 36814844 PMCID: PMC9939361 DOI: 10.1016/j.crmeth.2022.100372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 10/11/2022] [Accepted: 12/06/2022] [Indexed: 12/31/2022]
Abstract
The development of protease-activatable drugs and diagnostics requires identifying substrates specific to individual proteases. However, this process becomes increasingly difficult as the number of target proteases increases because most substrates are promiscuously cleaved by multiple proteases. We introduce a method-substrate libraries for compressed sensing of enzymes (SLICE)-for selecting libraries of promiscuous substrates that classify protease mixtures (1) without deconvolution of compressed signals and (2) without highly specific substrates. SLICE ranks substrate libraries using a compression score (C), which quantifies substrate orthogonality and protease coverage. This metric is predictive of classification accuracy across 140 in silico (Pearson r = 0.71) and 55 in vitro libraries (r = 0.55). Using SLICE, we select a two-substrate library to classify 28 samples containing 11 enzymes in plasma (area under the receiver operating characteristic curve [AUROC] = 0.93). We envision that SLICE will enable the selection of libraries that capture information from hundreds of enzymes using fewer substrates for applications like activity-based sensors for imaging and diagnostics.
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Affiliation(s)
- Brandon Alexander Holt
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Hong Seo Lim
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Anirudh Sivakumar
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Hathaichanok Phuengkham
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Melanie Su
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - McKenzie Tuttle
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Yilin Xu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Haley Liakakos
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Peng Qiu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
| | - Gabriel A. Kwong
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Tech College of Engineering and Emory School of Medicine, Atlanta, GA 30332, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Atlanta, GA 30332, USA
- Institute for Electronics and Nanotechnology, Georgia Tech, Atlanta, GA 30332, USA
- Integrated Cancer Research Center, Georgia Tech, Atlanta, GA 30332, USA
- Georgia ImmunoEngineering Consortium, Georgia Tech and Emory University, Atlanta, GA 30332, USA
- Emory School of Medicine, Atlanta, GA 30332, USA
- Emory Winship Cancer Institute, Atlanta, GA 30322, USA
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6
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Halpin JC, Whitney D, Rigoldi F, Sivaraman V, Singer A, Keating AE. Molecular determinants of TRAF6 binding specificity suggest that native interaction partners are not optimized for affinity. Protein Sci 2022; 31:e4429. [PMID: 36305766 PMCID: PMC9597381 DOI: 10.1002/pro.4429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/14/2022] [Accepted: 08/19/2022] [Indexed: 11/25/2022]
Abstract
TRAF6 is an adaptor protein involved in signaling pathways that are essential for development and the immune system. It participates in many protein-protein interactions, some of which are mediated by the C-terminal MATH domain, which binds to short peptide segments containing the motif PxExx[FYWHDE], where x is any amino acid. Blocking MATH domain interactions is associated with favorable effects in various disease models. To better define TRAF6 MATH domain binding preferences, we screened a combinatorial library using bacterial cell-surface peptide display. We identified 236 of the best TRAF6-interacting peptides and a set of 1,200 peptides that match the sequence PxE but do not bind TRAF6 MATH. The peptides that were most enriched in the screen bound TRAF6 tighter than previously measured native peptides. To better understand the structural basis for TRAF6 interaction preferences, we built all-atom structural models of the MATH domain in complex with high-affinity binders and nonbinders identified in the screen. We identified favorable interactions for motif features in binders as well as negative design elements distributed across the motif that can disfavor or preclude binding. Searching the human proteome revealed that the most biologically relevant TRAF6 motif matches occupy a different sequence space from the best hits discovered in combinatorial library screening, suggesting that native interactions are not optimized for affinity. Our experimentally determined binding preferences and structural models support the design of peptide-based interaction inhibitors with higher affinities than endogenous TRAF6 ligands.
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Affiliation(s)
| | | | | | | | | | - Amy E. Keating
- MIT Department of BiologyCambridgeMassachusettsUSA
- MIT Department of Biological EngineeringCambridgeMassachusettsUSA
- Koch Institute for Integrative Cancer ResearchCambridgeMassachusettsUSA
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7
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Hermansen S, Ryoo D, Orwick-Rydmark M, Saragliadis A, Gumbart JC, Linke D. The Role of Extracellular Loops in the Folding of Outer Membrane Protein X (OmpX) of Escherichia coli. Front Mol Biosci 2022; 9:918480. [PMID: 35911955 PMCID: PMC9329534 DOI: 10.3389/fmolb.2022.918480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/16/2022] [Indexed: 11/25/2022] Open
Abstract
The outer membrane of Gram-negative bacteria acts as an additional diffusion barrier for solutes and nutrients. It is perforated by outer membrane proteins (OMPs) that function most often as diffusion pores, but sometimes also as parts of larger cellular transport complexes, structural components of the cell wall, or even as enzymes. These OMPs often have large loops that protrude into the extracellular environment, which have promise for biotechnological applications and as therapeutic targets. Thus, understanding how modifications to these loops affect OMP stability and folding is critical for their efficient application. In this work, the small outer membrane protein OmpX was used as a model system to quantify the effects of loop insertions on OMP folding and stability. The insertions were varied according to both hydrophobicity and size, and their effects were determined by assaying folding into detergent micelles in vitro by SDS-PAGE and in vivo by isolating the outer membrane of cells expressing the constructs. The different insertions were also examined in molecular dynamics simulations to resolve how they affect OmpX dynamics in its native outer membrane. The results indicate that folding of OMPs is affected by both the insert length and by its hydrophobic character. Small insertions sometimes even improved the folding efficiency of OmpX, while large hydrophilic inserts reduced it. All the constructs that were found to fold in vitro could also do so in their native environment. One construct that could not fold in vitro was transported to the OM in vivo, but remained unfolded. Our results will help to improve the design and efficiency of recombinant OMPs used for surface display.
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Affiliation(s)
- Simen Hermansen
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - David Ryoo
- Interdisciplinary Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, GA, United States
| | - Marcella Orwick-Rydmark
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Athanasios Saragliadis
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - James C. Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA, United States
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
- *Correspondence: Dirk Linke,
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8
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Mazraeh D, Di Ventura B. Synthetic microbiology applications powered by light. Curr Opin Microbiol 2022; 68:102158. [PMID: 35660240 DOI: 10.1016/j.mib.2022.102158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 11/17/2022]
Abstract
Synthetic biology is a field of research in which molecular parts (mostly nucleic acids and proteins) are de novo created or modified and then used either alone or in combination to achieve new functions that can help solve the problems of our modern society. In synthetic microbiology, microbes are employed rather than other organisms or cell-free systems. Optogenetics, a relatively recently established technology that relies on the use of genetically encoded photosensitive proteins to control biological processes with high spatiotemporal precision, offers the possibility to empower synthetic (micro)biology applications due to the many positive features that light has as an external trigger. In this review, we describe recent synthetic microbiology applications that made use of optogenetics after briefly introducing the molecular mechanism behind some of the most employed optogenetic tools. We highlight the power and versatility of this technique, which opens up new horizons for both research and industry.
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Affiliation(s)
- Daniel Mazraeh
- Signaling Research Centres BIOSS and CIBSS, and Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Barbara Di Ventura
- Signaling Research Centres BIOSS and CIBSS, and Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany.
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9
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Wang X, Bernstein HD. The Escherichia coli outer membrane protein OmpA acquires secondary structure prior to its integration into the membrane. J Biol Chem 2022; 298:101802. [PMID: 35257747 PMCID: PMC8987393 DOI: 10.1016/j.jbc.2022.101802] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 11/25/2022] Open
Abstract
Almost all proteins that reside in the outer membrane (OM) of Gram-negative bacteria contain a membrane-spanning segment that folds into a unique β barrel structure and inserts into the membrane by an unknown mechanism. To obtain further insight into outer membrane protein (OMP) biogenesis, we revisited the surprising observation reported over 20 years ago that the Escherichia coli OmpA β barrel can be assembled into a native structure in vivo when it is expressed as two noncovalently linked fragments. Here, we show that disulfide bonds between β strand 4 in the N-terminal fragment and β strand 5 in the C-terminal fragment can form in the periplasmic space and greatly increase the efficiency of assembly of "split" OmpA, but only if the cysteine residues are engineered in perfect register (i.e., they are aligned in the fully folded β barrel). In contrast, we observed only weak disulfide bonding between β strand 1 in the N-terminal fragment and β strand 8 in the C-terminal fragment that would form a closed or circularly permutated β barrel. Our results not only demonstrate that β barrels begin to fold into a β-sheet-like structure before they are integrated into the OM but also help to discriminate among the different models of OMP biogenesis that have been proposed.
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Affiliation(s)
- Xu Wang
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Harris D Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
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10
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Assi HH, Wong C, Tipton KA, Mei L, Wong K, Razo J, Chan C, Howng B, Sagert J, Krimm M, Diep L, Jang A, Nguyen MT, Lapuyade N, Singson V, Villanueva R, Paidhungat M, Liu S, Rangan V, Vasiljeva O, West JW, Richardson JH, Irving B, Daniel D, Belvin M, Kavanaugh WM. Conditional PD-1/PD-L1 Probody Therapeutics Induce Comparable Antitumor Immunity but Reduced Systemic Toxicity Compared with Traditional Anti-PD-1/PD-L1 Agents. Cancer Immunol Res 2021; 9:1451-1464. [PMID: 34635485 PMCID: PMC9414278 DOI: 10.1158/2326-6066.cir-21-0031] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 05/28/2021] [Accepted: 10/08/2021] [Indexed: 01/07/2023]
Abstract
Immune-checkpoint blockade has revolutionized cancer treatment. However, most patients do not respond to single-agent therapy. Combining checkpoint inhibitors with other immune-stimulating agents increases both efficacy and toxicity due to systemic T-cell activation. Protease-activatable antibody prodrugs, known as Probody therapeutics (Pb-Tx), localize antibody activity by attenuating capacity to bind antigen until protease activation in the tumor microenvironment. Herein, we show that systemic administration of anti-programmed cell death ligand 1 (anti-PD-L1) and anti-programmed cell death protein 1 (anti-PD-1) Pb-Tx to tumor-bearing mice elicited antitumor activity similar to that of traditional PD-1/PD-L1-targeted antibodies. Pb-Tx exhibited reduced systemic activity and an improved nonclinical safety profile, with markedly reduced target occupancy on peripheral T cells and reduced incidence of early-onset autoimmune diabetes in nonobese diabetic mice. Our results confirm that localized PD-1/PD-L1 inhibition by Pb-Tx can elicit robust antitumor immunity and minimize systemic immune-mediated toxicity. These data provide further preclinical rationale to support the ongoing development of the anti-PD-L1 Pb-Tx CX-072, which is currently in clinical trials.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - W. Michael Kavanaugh
- Corresponding Author: W. Michael Kavanaugh, CytomX Therapeutics, Inc., 151 Oyster Point Boulevard, Suite 400, South San Francisco, CA 94080. Phone: 650-763-9949; E-mail:
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11
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Howng B, Winter MB, LePage C, Popova I, Krimm M, Vasiljeva O. Novel Ex Vivo Zymography Approach for Assessment of Protease Activity in Tissues with Activatable Antibodies. Pharmaceutics 2021; 13:pharmaceutics13091390. [PMID: 34575469 PMCID: PMC8471274 DOI: 10.3390/pharmaceutics13091390] [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: 08/05/2021] [Accepted: 08/17/2021] [Indexed: 12/27/2022] Open
Abstract
Proteases are involved in the control of numerous physiological processes, and their dysregulation has been identified in a wide range of pathologies, including cancer. Protease activity is normally tightly regulated post-translationally and therefore cannot be accurately estimated based on mRNA or protein expression alone. While several types of zymography approaches to estimate protease activity exist, there remains a need for a robust and reliable technique to measure protease activity in biological tissues. We present a novel quantitative ex vivo zymography (QZ) technology based on Probody® therapeutics (Pb-Tx), a novel class of protease-activated cancer therapeutics that contain a substrate linker cleavable by tumor-associated proteases. This approach enables the measurement and comparison of protease activity in biological tissues via the detection of Pb-Tx activation. By exploiting substrate specificity and selectivity, cataloguing and differentiating protease activities is possible, with further refinement achieved using protease-specific inhibitors. Using the QZ assay and human tumor xenografts, patient tumor tissues, and patient plasma, we characterized protease activity in preclinical and clinical samples. The QZ assay offers the potential to increase our understanding of protease activity in tissues and inform diagnostic and therapeutic development for diseases, such as cancer, that are characterized by dysregulated proteolysis.
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12
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Improved Microbial Fuel Cell Performance by Engineering E. coli for Enhanced Affinity to Gold. ENERGIES 2021. [DOI: 10.3390/en14175389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microorganism affinity for surfaces can be controlled by introducing material binding motifs into proteins such as fimbrial tip and outer membrane proteins. Here, controlled surface affinity is used to manipulate and enhance electrical power production in a typical bioelectrochemical system, a microbial fuel cell (MFC). Specifically, gold-binding motifs of various affinity were introduced into two scaffolds in Escherichia coli: eCPX, a modified version of outer membrane protein X (OmpX), and FimH, the tip protein of the fimbriae. The behavior of these strains on gold electrodes was examined in small-scale (240 µL) MFCs and 40 mL U-tube MFCs. A clear correlation between the affinity of a strain for a gold surface and the peak voltage produced during MFC operation is shown in the small-scale MFCs; strains displaying peptides with high affinity for gold generate potentials greater than 80 mV while strains displaying peptides with minimal affinity to gold produce potentials around 30 mV. In the larger MFCs, E. coli strains with high affinity to gold exhibit power densities up to 0.27 mW/m2, approximately a 10-fold increase over unengineered strains lacking displayed peptides. Moreover, in the case of the modified FimH strains, this increased power production is sustained for five days.
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13
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Lee J, Song WJ. Folding of Circularly Permuted and Split Outer Membrane Protein F via Electrostatic Interactions with Terminal Residues. Biochemistry 2021; 60:1787-1796. [PMID: 34060805 DOI: 10.1021/acs.biochem.1c00195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Membrane proteins are essential targets in drug design, biosensing, and catalysis. In this study, we explored the folding of engineered outer membrane protein F (OmpF), an abundant and functional β-barrel protein expressed in Gram-negative bacteria. We carried out circular permutation, splitting and self-complementation, and point mutation. The folding efficiency and kinetic analyses demonstrated that the N- and C-terminal residues of OmpF played critical roles in folding via electrostatic interactions with lipid headgroups. Our results indicate that native porins without charged terminal residues may be tightly downregulated to retain the integrity of the outer membrane, and this modification may facilitate the insertion and folding of modified membrane proteins under in vitro and in vivo conditions for various applications.
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Affiliation(s)
- Jaewon Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Woon Ju Song
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
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14
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Dong H, Sarkes DA, Stratis-Cullum DN, Hurley MM. Direct conjugation of fluorescent quantum dots with E. coli via surface-displayed histidine-containing peptides. Colloids Surf B Biointerfaces 2021; 203:111730. [PMID: 33853002 DOI: 10.1016/j.colsurfb.2021.111730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/27/2021] [Accepted: 03/29/2021] [Indexed: 10/21/2022]
Abstract
Biocompatible approaches to labeling bacteria with fluorescent nanoparticles are essential in order to create living bacterial bioconjugates for imaging, biosensors, medicine, and other applications. Herein we report the direct conjugation of carboxyl quantum dots (QDs) with E. coli outer membrane via surface-displayed binding peptides. The histidine-containing peptide H6G9 was displayed at the N-terminus of membrane-embedded enhanced circularly permuted outer membrane protein X (eCPX) scaffold, which was expressed upon chemical induction. The presence of the binding peptide creates an environment distinct from the negatively charged E. coli surface and provides strong binding affinity to carboxyl quantum dots (QDs). Transmission electron microscopy (TEM) analysis of E. coli-QD bioconjugates revealed high loading densities of these QDs immobilized on the cell surface, even when adding a very low concentration (10 μg/mL) of QDs in order to reduce the cell exposure. These hybrid cells strongly fluoresce with each of the distinct colors of loaded QDs with different emission wavelengths, which can be easily visualized by fluorescence microscopy or differentiated using flow cytometry. Importantly, the E. coli-QD bioconjugates were highly viable and maintained the ability to grow and divide. This study demonstrates a simple, direct, and highly efficient method for labelling bacteria with QDs, without significantly compromising the vitality of the cells.
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Affiliation(s)
- Hong Dong
- DEVCOM Army Research Laboratory, Biotechnology Branch, 2800 Powder Mill Road, Adelphi, MD, 20783, United States.
| | - Deborah A Sarkes
- DEVCOM Army Research Laboratory, Biotechnology Branch, 2800 Powder Mill Road, Adelphi, MD, 20783, United States
| | - Dimitra N Stratis-Cullum
- DEVCOM Army Research Laboratory, Biotechnology Branch, 2800 Powder Mill Road, Adelphi, MD, 20783, United States
| | - Margaret M Hurley
- DEVCOM Army Research Laboratory, Biotechnology Branch, 2800 Powder Mill Road, Adelphi, MD, 20783, United States
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15
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Vasiljeva O, Menendez E, Nguyen M, Craik CS, Michael Kavanaugh W. Monitoring protease activity in biological tissues using antibody prodrugs as sensing probes. Sci Rep 2020; 10:5894. [PMID: 32246002 PMCID: PMC7125177 DOI: 10.1038/s41598-020-62339-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 03/04/2020] [Indexed: 01/09/2023] Open
Abstract
Proteases have been implicated in the development of many pathological conditions, including cancer. Detection of protease activity in diseased tissues could therefore be useful for diagnosis, prognosis, and the development of novel therapeutic approaches. Due to tight post-translational regulation, determination of the expression level of proteases alone may not be indicative of protease activities, and new methods for measuring protease activity in biological samples such as tumor biopsies are needed. Here we report a novel zymography-based technique, called the IHZTM assay, for the detection of specific protease activities in situ. The IHZ assay involves imaging the binding of a protease-activated monoclonal antibody prodrug, called a Probody® therapeutic, to tissue. Probody therapeutics are fully recombinant, masked antibodies that can only bind target antigen after removal of the mask by a selected protease. A fluorescently labeled Probody molecule is incubated with a biological tissue, thereby enabling its activation by tissue endogenous proteases. Protease activity is measured by imaging the activated Probody molecule binding to antigen present in the sample. The method was evaluated in xenograft tumor samples using protease specific substrates and inhibitors, and the measurements correlated with efficacy of the respective Probody therapeutics. Using this technique, a diverse profile of MMP and serine protease activities was characterized in breast cancer patient tumor samples. The IHZ assay represents a new type of in situ zymography technique that can be used for the screening of disease-associated proteases in patient samples from multiple pathological conditions.
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Affiliation(s)
- Olga Vasiljeva
- CytomX Therapeutics, Inc.; 151 Oyster Point Blvd. Suite 400, South San Francisco, California, 94080, USA.
| | - Elizabeth Menendez
- CytomX Therapeutics, Inc.; 151 Oyster Point Blvd. Suite 400, South San Francisco, California, 94080, USA
| | - Margaret Nguyen
- CytomX Therapeutics, Inc.; 151 Oyster Point Blvd. Suite 400, South San Francisco, California, 94080, USA
| | - Charles S Craik
- Department of Pharmaceutical Chemistry, University of California, 600 16th Street, San Francisco, CA, 94143, USA
| | - W Michael Kavanaugh
- CytomX Therapeutics, Inc.; 151 Oyster Point Blvd. Suite 400, South San Francisco, California, 94080, USA
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16
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Navaratna T, Atangcho L, Mahajan M, Subramanian V, Case M, Min A, Tresnak D, Thurber GM. Directed Evolution Using Stabilized Bacterial Peptide Display. J Am Chem Soc 2020; 142:1882-1894. [PMID: 31880439 DOI: 10.1021/jacs.9b10716] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chemically stabilized peptides have attracted intense interest by academics and pharmaceutical companies due to their potential to hit currently "undruggable" targets. However, engineering an optimal sequence, stabilizing linker location, and physicochemical properties is a slow and arduous process. By pairing non-natural amino acid incorporation and cell surface click chemistry in bacteria with high-throughput sorting, we developed a method to quantitatively select high affinity ligands and applied the Stabilized Peptide Evolution by E. coli Display technique to develop disrupters of the therapeutically relevant MDM2-p53 interface. Through in situ stabilization on the bacterial surface, we demonstrate rapid isolation of stabilized peptides with improved affinity and novel structures. Several peptides evolved a second loop including one sequence (Kd = 1.8 nM) containing an i, i+4 disulfide bond. NMR structural determination indicated a bent helix in solution and bound to MDM2. The bicyclic peptide had improved protease stability, and we demonstrated that protease resistance could be measured both on the bacterial surface and in solution, enabling the method to test and/or screen for additional drug-like properties critical for biologically active compounds.
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Affiliation(s)
- Tejas Navaratna
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Lydia Atangcho
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Mukesh Mahajan
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | | | - Marshall Case
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Andrew Min
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Daniel Tresnak
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Greg M Thurber
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States.,Department of Biomedical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
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17
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Stellwagen SD, Sarkes DA, Adams BL, Hunt MA, Renberg RL, Hurley MM, Stratis-Cullum DN. The next generation of biopanning: next gen sequencing improves analysis of bacterial display libraries. BMC Biotechnol 2019; 19:100. [PMID: 31864334 PMCID: PMC6925417 DOI: 10.1186/s12896-019-0577-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 11/12/2019] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Bacterial surface display libraries are a popular tool for novel ligand discovery due to their ease of manipulation and rapid growth rates. These libraries typically express a scaffold protein embedded within the outer membrane with a short, surface-exposed peptide that is either terminal or is incorporated into an outer loop, and can therefore interact with and bind to substrates of interest. RESULTS In this study, we employed a novel bacterial peptide display library which incorporates short 15-mer peptides on the surface of E. coli, co-expressed with the inducible red fluorescent protein DsRed in the cytosol, to investigate population diversity over two rounds of biopanning. The naive library was used in panning trials to select for binding affinity against 3D printing plastic coupons made from polylactic acid (PLA). Resulting libraries were then deep-sequenced using next generation sequencing (NGS) to investigate selection and diversity. CONCLUSIONS We demonstrated enrichment for PLA binding versus a sapphire control surface, analyzed population composition, and compared sorting rounds using a binding assay and fluorescence microscopy. The capability to produce and describe display libraries through NGS across rounds of selection allows a deeper understanding of population dynamics that can be better directed towards peptide discovery.
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Affiliation(s)
- Sarah D. Stellwagen
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
- Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, 21250 MD USA
| | - Deborah A. Sarkes
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
| | - Bryn L. Adams
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
| | - Mia A. Hunt
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
- General Technical Services, Suite 301, 1451 Route 34 South, Wall Township, 07727 NJ USA
| | - Rebecca L. Renberg
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
- General Technical Services, Suite 301, 1451 Route 34 South, Wall Township, 07727 NJ USA
| | - Margaret M. Hurley
- Biotechnology Branch, CCDC US Army Research Laboratory, 2800 Powder Mill Rd, Adelphi, 20783 MD USA
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18
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FimH-based display of functional eukaryotic proteins on bacteria surfaces. Sci Rep 2019; 9:8410. [PMID: 31182802 PMCID: PMC6557881 DOI: 10.1038/s41598-019-44883-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/20/2019] [Indexed: 02/07/2023] Open
Abstract
The demand for recombinant proteins for analytic and therapeutic purposes is increasing; however, most currently used bacterial production systems accumulate the recombinant proteins in the intracellular space, which requires denaturating procedures for harvesting and functional testing. We here present a novel FimH-based expression system that enables display of fully functional eukaryotic proteins while preventing technical difficulties in translocating, folding, stabilizing and isolating the displayed proteins. As examples, Gaussia Luciferase (GLuc), epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and epiregulin (EPRG) were expressed as FimH fusion proteins on the surface of E. coli bacteria. The fusion proteins were functionally active and could be released from the bacterial surface by specific proteolytic cleavage into the culture supernatant allowing harvesting of the produced proteins. EGFR ligands, produced as FimH fusion proteins and released by proteolytic cleavage, bound to the EGF receptor (EGFR) on cancer cells inducing EGFR phosphorylation. In another application of the technology, GLuc-FimH expressed on the surface of bacteria was used to track tumor-infiltrating bacteria by bioluminescence imaging upon application to mice, thereby visualizing the colonization of transplanted tumors. The examples indicate that the FimH-fusion protein technology can be used in various applications that require functionally active proteins to be displayed on bacterial surfaces or released into the culture supernatant.
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19
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Granhøj J, Dimke H, Svenningsen P. A bacterial display system for effective selection of protein-biotin ligase BirA variants with novel peptide specificity. Sci Rep 2019; 9:4118. [PMID: 30858523 PMCID: PMC6411976 DOI: 10.1038/s41598-019-40984-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 02/14/2019] [Indexed: 11/09/2022] Open
Abstract
Biotinylation creates a sensitive and specific tag for purification and detection of target proteins. The E. coli protein-biotin ligase BirA biotinylates a lysine within a synthetic biotin acceptor peptide (AP) and allow for specific tagging of proteins fused to the AP. The approach is not applicable to unmodified proteins, and we sought to develop an effective selection system that could form the basis for directed evolution of novel BirA variants with specificity towards unmodified proteins. The system was based on bacterial display of a target peptide sequence, which could be biotinylated by cytosolic BirA variants before being displayed on the surface. In a model selection, the bacterial display system accomplished >1.000.000 enrichment in a single selection step. A randomly mutated BirA library was used to identify novel variants. Bacteria displaying peptide sequences from 13 out of 14 tested proteins were strongly enriched after 3-5 selection rounds. Moreover, a clone selected for biotinylation of a C-terminal peptide from red-fluorescent protein TagRFP showed biotinylation of the native protein. Thus, active BirA variants with novel activity are effectively isolated with our bacterial display system and provides a basis for the development of BirA variants for site-selective biotinylation.
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Affiliation(s)
- Jeff Granhøj
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Henrik Dimke
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Per Svenningsen
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
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20
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Bhagwat SR, Hajela K, Kumar A. Proteolysis to Identify Protease Substrates: Cleave to Decipher. Proteomics 2018; 18:e1800011. [DOI: 10.1002/pmic.201800011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 04/03/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Sonali R. Bhagwat
- Discipline of Biosciences and Biomedical Engineering; Indian Institute of Technology; Indore 453552 Simrol India
| | - Krishnan Hajela
- School of Life Sciences; Devi Ahilya Vishwavidyalaya; Indore 452001 India
| | - Amit Kumar
- Discipline of Biosciences and Biomedical Engineering; Indian Institute of Technology; Indore 453552 Simrol India
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21
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Dong H, Sarkes DA, Rice JJ, Hurley MM, Fu AJ, Stratis-Cullum DN. Living Bacteria-Nanoparticle Hybrids Mediated through Surface-Displayed Peptides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:5837-5848. [PMID: 29692178 DOI: 10.1021/acs.langmuir.8b00114] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this study, we investigated the preparation of living bacteria-nanoparticle hybrids mediated by surface-displayed peptides. The assembly of metallic nanoparticles on living bacteria has been achieved under mild conditions utilizing metal-peptide interactions, whereas the viability of the bacterial cells was greatly preserved. Escherichia coli was engineered with inducible gene circuits to control the display of peptides with desired sequences. Several designed peptide sequences as well as known gold-binding peptides were expressed on the cell surface using enhanced circularly permuted outer membrane protein X (eCPX) scaffolds. Driven by metal-peptide affinity, "biofriendly" citrate-stabilized gold nanoparticles were self-assembled onto the surface of bacteria with displayed peptides, which required overcoming the repulsive force between negatively charged nanoparticles and negatively charged cells. The bacteria/Au nanoparticle hybrids were highly viable and maintained the ability to grow and divide, which is a crucial step toward the creation of living material systems. Further activity and preservation of the bacterial hybrid assembly was demonstrated. The method described herein enables the conjugation of bacterial surfaces with diverse metal-rich nanoparticles in an inducible, and therefore easily controlled, manner. The expressed peptide sequences can be easily modified to alter the binding affinity and specificity for a wide variety of materials to form on-demand, high-density living biohybrids.
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Affiliation(s)
- Hong Dong
- Biotechnology Branch , US Army Research Laboratory , 2800 Powder Mill Road , Adelphi , Maryland 20783 , United States
- General Technical Services , 1451 Route 34 South , Wall Township , New Jersey 07727 , United States
| | - Deborah A Sarkes
- Biotechnology Branch , US Army Research Laboratory , 2800 Powder Mill Road , Adelphi , Maryland 20783 , United States
| | - Jeffrey J Rice
- Department of Chemical Engineering , Auburn University , 212 Ross Hall , Auburn , Alabama 36849 , United States
- Oak Ridge Associated Universities , 4692 Millennium Drive, Suite 101 , Belcamp , Maryland 21017 , United States
| | - Margaret M Hurley
- Biotechnology Branch , US Army Research Laboratory , 2800 Powder Mill Road , Adelphi , Maryland 20783 , United States
| | - Adele J Fu
- Biotechnology Branch , US Army Research Laboratory , 2800 Powder Mill Road , Adelphi , Maryland 20783 , United States
- Oak Ridge Associated Universities , 4692 Millennium Drive, Suite 101 , Belcamp , Maryland 21017 , United States
| | - Dimitra N Stratis-Cullum
- Biotechnology Branch , US Army Research Laboratory , 2800 Powder Mill Road , Adelphi , Maryland 20783 , United States
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22
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Chaturvedi D, Mahalakshmi R. Folding Determinants of Transmembrane β-Barrels Using Engineered OMP Chimeras. Biochemistry 2018. [DOI: 10.1021/acs.biochem.8b00012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Deepti Chaturvedi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal − 462066, India
| | - Radhakrishnan Mahalakshmi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal − 462066, India
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23
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Sarkes DA, Jahnke JP, Stratis-Cullum DN. Semi-automated Biopanning of Bacterial Display Libraries for Peptide Affinity Reagent Discovery and Analysis of Resulting Isolates. J Vis Exp 2017. [PMID: 29286465 PMCID: PMC5755526 DOI: 10.3791/56061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Biopanning bacterial display libraries is a proven technique for peptide affinity reagent discovery for recognition of both biotic and abiotic targets. Peptide affinity reagents can be used for similar applications to antibodies, including sensing and therapeutics, but are more robust and able to perform in more extreme environments. Specific enrichment of peptide capture agents to a protein target of interest is enhanced using semi-automated sorting methods which improve binding and wash steps and therefore decrease the occurrence of false positive binders. A semi-automated sorting method is described herein for use with a commercial automated magnetic-activated cell sorting device with an unconstrained bacterial display sorting library expressing random 15-mer peptides. With slight modifications, these methods are extendable to other automated devices, other sorting libraries, and other organisms. A primary goal of this work is to provide a comprehensive methodology and expound the thought process applied in analyzing and minimizing the resulting pool of candidates. These techniques include analysis of on-cell binding using fluorescence-activated cell sorting (FACS), to assess affinity and specificity during sorting and in comparing individual candidates, and the analysis of peptide sequences to identify trends and consensus sequences for understanding and potentially improving the affinity to and specificity for the target of interest.
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Affiliation(s)
- Deborah A Sarkes
- Sensors and Electron Devices Directorate, US Army Research Laboratory;
| | - Justin P Jahnke
- Sensors and Electron Devices Directorate, US Army Research Laboratory
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24
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Salema V, Fernández LÁ. Escherichia coli surface display for the selection of nanobodies. Microb Biotechnol 2017; 10:1468-1484. [PMID: 28772027 PMCID: PMC5658595 DOI: 10.1111/1751-7915.12819] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 12/29/2022] Open
Abstract
Nanobodies (Nbs) are the smallest functional antibody fragments known in nature and have multiple applications in biomedicine or environmental monitoring. Nbs are derived from the variable segment of camelid heavy chain-only antibodies, known as VHH. For selection, libraries of VHH gene segments from naïve, immunized animals or of synthetic origin have been traditionally cloned in E. coli phage display or yeast display systems, and clones binding the target antigen recovered, usually from plastic surfaces with the immobilized antigen (phage display) or using fluorescence-activated cell sorting (FACS; yeast display). This review briefly describes these conventional approaches and focuses on the distinct properties of an E. coli display system developed in our laboratory, which combines the benefits of both phage display and yeast display systems. We demonstrate that E. coli display using an N-terminal domain of intimin is an effective platform for the surface display of VHH libraries enabling selection of high-affinity Nbs by magnetic cell sorting and direct selection on live mammalian cells displaying the target antigen on their surface. Flow cytometry analysis of E. coli bacteria displaying the Nbs on their surface allows monitoring of the selection process, facilitates screening, characterization of antigen-binding clones, specificity, ligand competition and estimation of the equilibrium dissociation constant (KD ).
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Affiliation(s)
- Valencio Salema
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología (CNB)Consejo Superior de Investigaciones Científicas (CSIC)MadridSpain
| | - Luis Ángel Fernández
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología (CNB)Consejo Superior de Investigaciones Científicas (CSIC)MadridSpain
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25
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Masked Chimeric Antigen Receptor for Tumor-Specific Activation. Mol Ther 2017; 25:274-284. [PMID: 28129121 DOI: 10.1016/j.ymthe.2016.10.011] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 09/22/2016] [Accepted: 10/05/2016] [Indexed: 12/13/2022] Open
Abstract
Adoptive cellular therapy based on chimeric antigen receptor (CAR)-engineered T (CAR-T) cells is a powerful form of cancer immunotherapy. CAR-T cells can be redirected to specifically recognize tumor-associated antigens (TAAs) and induce high levels of antitumor activity. However, they may also display "on-target off-tumor" toxicities, resulting from low-level expression of TAAs in healthy tissues. These adverse effects have raised considerable safety concerns and limited the clinical application of this otherwise promising therapeutic modality. To minimize such side effects, we have designed an epidermal growth factor receptor (EGFR)-specific masked CAR (mCAR), which consists of a masking peptide that blocks the antigen-binding site and a protease-sensitive linker. Proteases commonly active in the tumor microenvironment can cleave the linker and disengage the masking peptide, thereby enabling CAR-T cells to recognize target antigens only at the tumor site. In vitro mCAR showed dramatically reduced antigen binding and antigen-specific activation in the absence of proteases, but normal levels of binding and activity upon treatment with certain proteases. Masked CAR-T cells also showed antitumor efficacy in vivo comparable to that of unmasked CAR. Our study demonstrates the feasibility of improving the safety profile of conventional CARs and may also inspire future design of CAR molecules targeting broadly expressed TAAs.
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26
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Ding L, Hao Z, Yuan Q, Xu P, Yu Y, Li D. Anti-human fibroblast growth factor-21 monoclonal antibody preparation, characterization and analysis of in vitro bioactivity. Exp Ther Med 2016; 12:3417-3424. [PMID: 27882173 DOI: 10.3892/etm.2016.3753] [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: 06/09/2015] [Accepted: 08/05/2016] [Indexed: 11/06/2022] Open
Abstract
Human fibroblast growth factor 21 (hFGF-21) is involved in numerous metabolic processes and elevated hFGF-21 levels are associated with many metabolic diseases. However, the role hFGF-21 serves in the metabolic system is not fully understood. A humanized anti-hFGF-21 monoclonal antibody (mAb) would provide a novel method for further investigations into the role hFGF-21 serves in the metabolic system and related diseases, which may reveal therapeutic targets for future treatment of these diseases. The present study aimed to prepare an anti-hFGF-21 mAb, followed by identification of its characteristics and bioactivity in vitro. The results of the present study identified that the anti-hFGF-21 mAb (clone 2D8) produced had good specificity, had an immunoglobulin isotype of IgG2b and a titer of 1:1.024×106. hFGF-21 was screened for epitopes using fluorescence-activated cell sorting, which revealed a specific 15 amino acid sequence (YQSEAHGLPLHLPGN) that the anti-hFGF-21 mAb recognized. In vitro bioactivity of anti-hFGF-21 was determined using a glucose uptake assay and by measuring the expression of glucose transporter 1 (GLUT1) messenger RNA (mRNA) in 3T3-L1 adipocytes. This revealed that hFGF-21-dependent glucose uptake and GLUT1 mRNA expression were negatively correlated with increasing levels of the anti-hFGF-21 mAb tested, and that hFGF-21 activity could be overcome by increasing concentrations of the mAb, demonstrating that the mAb has hFGF-21-neutralizing activity in vitro.
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Affiliation(s)
- Liangjun Ding
- Biopharmaceutical Department, College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
| | - Zhichao Hao
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang 150069, P.R. China
| | - Qingyan Yuan
- Biopharmaceutical Department, College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
| | - Pengfei Xu
- Biopharmaceutical Department, College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
| | - Yinhang Yu
- Biopharmaceutical Department, College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
| | - Deshan Li
- Biopharmaceutical Department, College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
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27
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Sarkes DA, Hurley MM, Stratis-Cullum DN. Unraveling the Roots of Selectivity of Peptide Affinity Reagents for Structurally Similar Ribosomal Inactivating Protein Derivatives. Molecules 2016; 21:E1504. [PMID: 27834872 PMCID: PMC6272918 DOI: 10.3390/molecules21111504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 11/02/2016] [Accepted: 11/04/2016] [Indexed: 11/17/2022] Open
Abstract
Peptide capture agents have become increasingly useful tools for a variety of sensing applications due to their ease of discovery, stability, and robustness. Despite the ability to rapidly discover candidates through biopanning bacterial display libraries and easily mature them to Protein Catalyzed Capture (PCC) agents with even higher affinity and selectivity, an ongoing challenge and critical selection criteria is that the peptide candidates and final reagent be selective enough to replace antibodies, the gold-standard across immunoassay platforms. Here, we have discovered peptide affinity reagents against abrax, a derivative of abrin with reduced toxicity. Using on-cell Fluorescence Activated Cell Sorting (FACS) assays, we show that the peptides are highly selective for abrax over RiVax, a similar derivative of ricin originally designed as a vaccine, with significant structural homology to abrax. We rank the newly discovered peptides for strongest affinity and analyze three observed consensus sequences with varying affinity and specificity. The strongest (Tier 1) consensus was FWDTWF, which is highly aromatic and hydrophobic. To better understand the observed selectivity, we use the XPairIt peptide-protein docking protocol to analyze binding location predictions of the individual Tier 1 peptides and consensus on abrax and RiVax. The binding location profiles on the two proteins are quite distinct, which we determine is due to differences in pocket size, pocket environment (including hydrophobicity and electronegativity), and steric hindrance. This study provides a model system to show that peptide capture candidates can be quite selective for a structurally similar protein system, even without further maturation, and offers an in silico method of analysis for understanding binding and down-selecting candidates.
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Affiliation(s)
- Deborah A Sarkes
- Biotechnology Branch, Sensors and Electron Devices Directorate, US Army Research Laboratory, Adelphi, MD 20783, USA.
| | - Margaret M Hurley
- Biotechnology Branch, Sensors and Electron Devices Directorate, US Army Research Laboratory, Adelphi, MD 20783, USA.
| | - Dimitra N Stratis-Cullum
- Biotechnology Branch, Sensors and Electron Devices Directorate, US Army Research Laboratory, Adelphi, MD 20783, USA.
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28
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A protease-based biosensor for the detection of schistosome cercariae. Sci Rep 2016; 6:24725. [PMID: 27090566 PMCID: PMC4835807 DOI: 10.1038/srep24725] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/30/2016] [Indexed: 01/18/2023] Open
Abstract
Parasitic diseases affect millions of people worldwide, causing debilitating illnesses and death. Rapid and cost-effective approaches to detect parasites are needed, especially in resource-limited settings. A common signature of parasitic diseases is the release of specific proteases by the parasites at multiple stages during their life cycles. To this end, we engineered several modular Escherichia coli and Bacillus subtilis whole-cell-based biosensors which incorporate an interchangeable protease recognition motif into their designs. Herein, we describe how several of our engineered biosensors have been applied to detect the presence and activity of elastase, an enzyme released by the cercarial larvae stage of Schistosoma mansoni. Collectively, S. mansoni and several other schistosomes are responsible for the infection of an estimated 200 million people worldwide. Since our biosensors are maintained in lyophilised cells, they could be applied for the detection of S. mansoni and other parasites in settings without reliable cold chain access.
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Pakulska MM, Miersch S, Shoichet MS. Designer protein delivery: From natural to engineered affinity-controlled release systems. Science 2016; 351:aac4750. [PMID: 26989257 DOI: 10.1126/science.aac4750] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exploiting binding affinities between molecules is an established practice in many fields, including biochemical separations, diagnostics, and drug development; however, using these affinities to control biomolecule release is a more recent strategy. Affinity-controlled release takes advantage of the reversible nature of noncovalent interactions between a therapeutic protein and a binding partner to slow the diffusive release of the protein from a vehicle. This process, in contrast to degradation-controlled sustained-release formulations such as poly(lactic-co-glycolic acid) microspheres, is controlled through the strength of the binding interaction, the binding kinetics, and the concentration of binding partners. In the context of affinity-controlled release--and specifically the discovery or design of binding partners--we review advances in in vitro selection and directed evolution of proteins, peptides, and oligonucleotides (aptamers), aided by computational design.
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Affiliation(s)
- Malgosia M Pakulska
- Department of Chemical Engineering and Applied Chemistry, Institute of Biomaterials and Biomedical Engineering, and Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Shane Miersch
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Molly S Shoichet
- Department of Chemical Engineering and Applied Chemistry, Institute of Biomaterials and Biomedical Engineering, and Donnelly Centre, University of Toronto, Toronto, Ontario, Canada. Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
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In Vitro Selection of Cancer Cell-Specific Molecular Recognition Elements from Amino Acid Libraries. J Immunol Res 2015; 2015:186586. [PMID: 26436100 PMCID: PMC4576012 DOI: 10.1155/2015/186586] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 08/17/2015] [Accepted: 08/23/2015] [Indexed: 11/27/2022] Open
Abstract
Differential cell systematic evolution of ligands by exponential enrichment (SELEX) is an in vitro selection method for obtaining molecular recognition elements (MREs) that specifically bind to individual cell types with high affinity. MREs are selected from initial large libraries of different nucleic or amino acids. This review outlines the construction of peptide and antibody fragment libraries as well as their different host types. Common methods of selection are also reviewed. Additionally, examples of cancer cell MREs are discussed, as well as their potential applications.
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31
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Wei L, Wang X, Li C, Li X, Yin Y, Li G. Colorimetric assay for protein detection based on "nano-pumpkin" induced aggregation of peptide-decorated gold nanoparticles. Biosens Bioelectron 2015; 71:348-352. [PMID: 25932793 DOI: 10.1016/j.bios.2015.04.072] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 04/14/2015] [Accepted: 04/17/2015] [Indexed: 02/07/2023]
Abstract
Small peptide can be used as an effective biological recognition element and provide an alternative tool for protein detection. However, the development of peptide-based detecting strategy still remains elusive due to the difficulty of signal transduction. Herein, we report a peptide-based colorimetric strategy for the detection of disease biomarker by using vascular endothelial growth factor receptor 1 (Flt-1) as an example. In this strategy, N-terminal aromatic residue-containing peptide modified gold nanoparticles (GNPs) can form bulky aggregate by the introduction of cucurbit[8]uril (CB[8]) that can selectively accommodate two N-terminal aromatic residue of peptides simultaneously regardless of their sequences. However, in the presence of Flt-1, the peptide can specifically bind to the protein molecule and the N-terminal aromatic residue will be occupied, resulting in little aggregation of GNPs. By taking advantage of the highly affinitive peptide and efficiency cross-linking effect of CB[8] to GNPs, colorimetric assay for protein detection can be achieved with a detection limit of 0.2 nM, which is comparable with traditional methods. The feasibility of our method has also been demonstrated in spiked serum sample, indicating potential application in the future.
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Affiliation(s)
- Luming Wei
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China
| | - Xiaoying Wang
- Department of Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China
| | - Chao Li
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China
| | - Xiaoxi Li
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China
| | - Yongmei Yin
- Department of Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China
| | - Genxi Li
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing 210093, PR China; Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
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De novo discovery of bioactive cyclic peptides using bacterial display and flow cytometry. Methods Mol Biol 2015; 1248:139-53. [PMID: 25616331 DOI: 10.1007/978-1-4939-2020-4_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Cyclic peptides are increasingly desired for their enhanced stability and pharmacologic properties. Due to their limited conformational flexibility, cyclic peptides with C-to-N-terminal peptide bond and a disulfide bridge can confer high target binding affinity and resistance to proteolytic enzymes. Challenging drug targets including protein interaction surfaces can be successfully targeted using peptides rather than small molecules or proteins. Peptides, capable of antibody-like affinities with increased potency, can be designed to fill in the gap between small molecules and larger proteins. However, cysteine-rich peptides with several disulfide bonds have limitations in production and purification. Therefore, we devised a strategy to identify cyclic peptides with single disulfide connectivity that offers desired properties along with ease in synthesis and production. Here, de novo design of cyclic peptides is demonstrated through screening of peptide libraries using bacterial display and cell sorting. Herein, a step-by-step protocol is presented to design and screen diverse peptide libraries to identify cyclic peptides with desired specificity and affinity towards arbitrary target proteins.
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Fleetwood F, Andersson KG, Ståhl S, Löfblom J. An engineered autotransporter-based surface expression vector enables efficient display of Affibody molecules on OmpT-negative E. coli as well as protease-mediated secretion in OmpT-positive strains. Microb Cell Fact 2014; 13:179. [PMID: 25547008 PMCID: PMC4304625 DOI: 10.1186/s12934-014-0179-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 12/09/2014] [Indexed: 12/20/2022] Open
Abstract
Background Cell display technologies (e.g. bacterial display) are attractive in directed evolution as they provide the option to use flow-cytometric cell sorting for selection from combinatorial libraries. The aim of this study was to engineer and investigate an expression vector system with dual functionalities: i) recombinant display of Affibody libraries on Escherichia coli for directed evolution and ii) small scale secreted production of candidate affinity proteins, allowing initial downstream characterizations prior to subcloning. Autotransporters form a class of surface proteins in Gram-negative bacteria that have potential for efficient translocation and tethering of recombinant passenger proteins to the outer membrane. We engineered a bacterial display vector based on the E. coli AIDA-I autotransporter for anchoring to the bacterial surface. Potential advantages of employing autotransporters combined with E. coli as host include: high surface expression level, high transformation frequency, alternative promoter systems available, efficient translocation to the outer membrane and tolerance for large multi-domain passenger proteins. Results The new vector was designed to comprise an expression cassette encoding for an Affibody molecule, three albumin binding domains for monitoring of surface expression levels, an Outer membrane Protease T (OmpT) recognition site for potential protease-mediated secretion of displayed affinity proteins and a histidine-tag for purification. A panel of vectors with different promoters were generated and evaluated, and suitable cultivation conditions were investigated. The results demonstrated a high surface expression level of the different evaluated Affibody molecules, high correlation between target binding and surface expression level, high signal-to-background ratio, efficient secretion and purification of binders in OmpT-positive hosts as well as tight regulation of surface expression for the titratable promoters. Importantly, a mock selection using FACS from a 1:100,000 background yielded around 20,000-fold enrichment in a single round and high viability of the isolated bacteria after sorting. Conclusions The new expression vectors are promising for combinatorial engineering of Affibody molecules and the strategy for small-scale production of soluble recombinant proteins has the potential to increase throughput of the entire discovery process. Electronic supplementary material The online version of this article (doi:10.1186/s12934-014-0179-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Filippa Fleetwood
- Division of Protein technology, School of Biotechnology, KTH Royal Institute of Technology, Stockholm, Sweden.
| | - Ken G Andersson
- Division of Protein technology, School of Biotechnology, KTH Royal Institute of Technology, Stockholm, Sweden.
| | - Stefan Ståhl
- Division of Protein technology, School of Biotechnology, KTH Royal Institute of Technology, Stockholm, Sweden.
| | - John Löfblom
- Division of Protein technology, School of Biotechnology, KTH Royal Institute of Technology, Stockholm, Sweden.
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Ma J, Li F, Liu R, Liang L, Ji Y, Wei C, Jiang M, Jia H, Ouyang P. Succinic acid production from sucrose and molasses by metabolically engineered E. coli using a cell surface display system. Biochem Eng J 2014. [DOI: 10.1016/j.bej.2014.08.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Desnoyers LR, Vasiljeva O, Richardson JH, Yang A, Menendez EEM, Liang TW, Wong C, Bessette PH, Kamath K, Moore SJ, Sagert JG, Hostetter DR, Han F, Gee J, Flandez J, Markham K, Nguyen M, Krimm M, Wong KR, Liu S, Daugherty PS, West JW, Lowman HB. Tumor-specific activation of an EGFR-targeting probody enhances therapeutic index. Sci Transl Med 2014; 5:207ra144. [PMID: 24132639 DOI: 10.1126/scitranslmed.3006682] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Target-mediated toxicity constitutes a major limitation for the development of therapeutic antibodies. To redirect the activity of antibodies recognizing widely distributed targets to the site of disease, we have applied a prodrug strategy to create an epidermal growth factor receptor (EGFR)-directed Probody therapeutic-an antibody that remains masked against antigen binding until activated locally by proteases commonly active in the tumor microenvironment. In vitro, the masked Probody showed diminished antigen binding and cell-based activities, but when activated by appropriate proteases, it regained full activity compared to the parental anti-EGFR antibody cetuximab. In vivo, the Probody was largely inert in the systemic circulation of mice, but was activated within tumor tissue and showed antitumor efficacy that was similar to that of cetuximab. The Probody demonstrated markedly improved safety and increased half-life in nonhuman primates, enabling it to be dosed safely at much higher levels than cetuximab. In addition, we found that both Probody-responsive xenograft tumors and primary tumor samples from patients were capable of activating the Probody ex vivo. Probodies may therefore improve the safety profile of therapeutic antibodies without compromising efficacy of the parental antibody and may enable the wider use of empowered antibody formats such as antibody-drug conjugates and bispecifics.
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Affiliation(s)
- Luc R Desnoyers
- CytomX Therapeutics Inc., 343 Oyster Point Boulevard, Suite 100, South San Francisco, CA 94080, USA
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Affiliation(s)
- Bethany Powell Gray
- Department of Internal Medicine and The Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8807, United States
| | - Kathlynn C. Brown
- Department of Internal Medicine and The Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8807, United States
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Methionine mutations of outer membrane protein X influence structural stability and beta-barrel unfolding. PLoS One 2013; 8:e79351. [PMID: 24265768 PMCID: PMC3827151 DOI: 10.1371/journal.pone.0079351] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 09/26/2013] [Indexed: 12/24/2022] Open
Abstract
We report the biochemical and biophysical characterization of outer membrane protein X (OmpX), an eight-stranded transmembrane β-barrel from E. coli, and compare the barrel behavior with a mutant devoid of methionine residues. Transmembrane outer membrane proteins of bacterial origin are known to display high tolerance to sequence rearrangements and mutations. Our studies with the triple mutant of OmpX that is devoid of all internal methionine residues (M18L; M21L; M118L) indicate that Met replacement has no influence on the refolding efficiency and structural characteristics of the protein. Surprisingly, the conserved substitution of Met→Leu leads to barrel destabilization and causes a lowering of the unfolding free energy by a factor of ∼8.5 kJ/mol, despite the mutations occurring at the loop regions. We report that the barrel destabilization is accompanied by a loss in cooperativity of unfolding in the presence of chemical denaturants. Furthermore, we are able to detect an unfolding intermediate in the Met-less barrel, whereas the parent protein exhibits a classic two-state unfolding. Thermal denaturation measurements also suggest a greater susceptibility of the OmpX barrel to heat, in the Met-less construct. Our studies reveal that even subtle variations in the extra-membrane region of rigid barrel structures such as OmpX, may bear severe implications on barrel stability. We propose that methionines contribute to efficient barrel structuring and protein-lipid interactions, and are therefore important elements of OmpX stability.
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Lee JH, Velmurugan N, Jeong KJ. Novel strategy for production of aggregation-prone proteins and lytic enzymes in Escherichia coli based on an anchored periplasmic expression system. J Biosci Bioeng 2013; 116:638-43. [DOI: 10.1016/j.jbiosc.2013.04.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 04/10/2013] [Accepted: 04/24/2013] [Indexed: 10/26/2022]
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Park TJ, Heo NS, Yim SS, Park JH, Jeong KJ, Lee SY. Surface display of recombinant proteins on Escherichia coli by BclA exosporium of Bacillus anthracis. Microb Cell Fact 2013; 12:81. [PMID: 24053632 PMCID: PMC3850424 DOI: 10.1186/1475-2859-12-81] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 09/17/2013] [Indexed: 11/12/2022] Open
Abstract
Background The anchoring motif is one of the most important aspects of cell surface display as well as efficient and stable display of target proteins. Thus, there is currently a need for the identification and isolation of novel anchoring motifs. Results A system for the display of recombinant proteins on the surface of Escherichia coli was developed using the Bacillus anthracis exosporal protein (BclA) as a new anchoring motif. For the surface display of recombinant proteins, the BAN display platform was constructed in which a target protein is linked to the C-terminus of N-terminal domain (21 amino acids) of BclA. The potential application of BAN platform for cell surface display was demonstrated with two model proteins of different size, the Bacillus sp. endoxylanase (XynA) and monooxygenase (P450 BM3m2). Through experimental analysis including outer membrane fractionation, confocal microscopy and activity assay, it was clearly confirmed that both model proteins were successfully displayed with high activities on the E. coli cell surface. Conclusions These results of this study suggest that the strategy employing the B. anthracis BclA as an anchoring motif is suitable for the display of heterologous proteins on the surface of E. coli and consequently for various biocatalytic applications as well as protein engineering.
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Affiliation(s)
- Tae Jung Park
- BioProcess Engineering Research Center, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
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Hamzeh-Mivehroud M, Alizadeh AA, Morris MB, Church WB, Dastmalchi S. Phage display as a technology delivering on the promise of peptide drug discovery. Drug Discov Today 2013; 18:1144-57. [PMID: 24051398 DOI: 10.1016/j.drudis.2013.09.001] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 08/29/2013] [Accepted: 09/09/2013] [Indexed: 01/24/2023]
Abstract
Phage display represents an important approach in the development pipeline for producing peptides and peptidomimetics therapeutics. Using randomly generated DNA sequences and molecular biology techniques, large diverse peptide libraries can be displayed on the phage surface. The phage library can be incubated with a target of interest and the phage which bind can be isolated and sequenced to reveal the displayed peptides' primary structure. In this review, we focus on the 'mechanics' of the phage display process, whilst highlighting many diverse and subtle ways it has been used to further the drug-development process, including the potential for the phage particle itself to be used as a drug carrier targeted to a particular pathogen or cell type in the body.
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Affiliation(s)
- Maryam Hamzeh-Mivehroud
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; School of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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41
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Adams BL, Finch AS, Hurley MM, Sarkes DA, Stratis-Cullum DN. Genetically engineered peptides for inorganics: study of an unconstrained bacterial display technology and bulk aluminum alloy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:4585-91. [PMID: 23868808 PMCID: PMC3793233 DOI: 10.1002/adma.201301646] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 05/20/2013] [Indexed: 05/16/2023]
Abstract
The first-ever peptide biomaterial discovery using an unconstrained engineered bacterial display technology is reported. Using this approach, we have developed genetically engineered peptide binders for a bulk aluminum alloy and use molecular dynamics simulation of peptide conformational fluctuations to demonstrate sequence-dependent, structure-function relationships for metal and metal oxide interactions.
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Affiliation(s)
- Bryn L Adams
- U.S. Army Research LaboratoryRDRL-SEE-B, 2800 Powder Mill Road, Adelphi, MD 20783, USA
| | - Amethist S Finch
- U.S. Army Research LaboratoryRDRL-SEE-B, 2800 Powder Mill Road, Adelphi, MD 20783, USA
| | - Margaret M Hurley
- US Army Research LaboratoryRDRL-WML-B, 4600 Deer Creek Loop, Aberdeen Proving Ground, MD 21005, USA
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Yim SS, An SJ, Han MJ, Choi JW, Jeong KJ. Isolation of a Potential Anchoring Motif Based on Proteome Analysis of Escherichia coli and Its Use for Cell Surface Display. Appl Biochem Biotechnol 2013; 170:787-804. [DOI: 10.1007/s12010-013-0236-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 04/09/2013] [Indexed: 11/28/2022]
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Krumpe LR, Mori T. Potential of phage-displayed peptide library technology to identify functional targeting peptides. Expert Opin Drug Discov 2013; 2:525. [PMID: 20150977 DOI: 10.1517/17460441.2.4.525] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Combinatorial peptide library technology is a valuable resource for drug discovery and development. Several peptide drugs developed through phage-displayed peptide library technology are presently in clinical trials and the authors envision that phage-displayed peptide library technology will assist in the discovery and development of many more. This review attempts to compile and summarize recent literature on targeting peptides developed through peptide library technology, with special emphasis on novel peptides with targeting capacity evaluated in vivo.
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Affiliation(s)
- Lauren Rh Krumpe
- SAIC-Frederick, Inc., Molecular Targets Development Program, NCI-Frederick, Frederick, Maryland 21702, USA
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44
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Spatola BN, Murray JA, Kagnoff M, Kaukinen K, Daugherty PS. Antibody repertoire profiling using bacterial display identifies reactivity signatures of celiac disease. Anal Chem 2013; 85:1215-22. [PMID: 23234559 PMCID: PMC3903178 DOI: 10.1021/ac303201d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A general strategy to identify serum antibody specificities associated with a given disease state and peptide reagents for their detection was developed using bacterial display peptide libraries and multiparameter flow cytometry (MPFC). Using sera from patients with celiac disease (CD) (n = 45) or healthy subjects (n = 40), bacterial display libraries were screened for peptides that react specifically with antibodies from CD patients and not with those from healthy patients. The libraries were screened for peptides that simultaneously cross-react with CD patient antibodies present in two separate patient groups labeled with spectrally distinct fluorophores but do not react with unlabeled non-CD antibodies, thus affording a quantitative separation. A panel of six unique peptide sequences yielded 85% sensitivity and 91% specificity (AUC = 0.91) on a set of 60 samples not used for discovery, using leave-one-out cross-validation. Individual peptides were dissimilar with known CD-specific antigens tissue transglutaminase (tTG) and deamidated gliadin, and the classifier accuracy was independent of anti-tTG antibody titer. These results demonstrate that bacterial display/MPFC provides a highly effective tool for the unbiased discovery of disease-associated antibody specificities and peptide reagents for their detection that may have broad utility for diagnostic development.
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Affiliation(s)
- Bradley N. Spatola
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Joseph A. Murray
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Martin Kagnoff
- Laboratory of Mucosal Immunology, Department of Medicine, University of California, San Diego, La Jolla, California 92093, United States
- Department of Pediatrics, University of California, San Diego, La Jolla, California 92093, United States
| | - Katri Kaukinen
- Department of Gastroenterology and Alimentary Tract Surgery, Tampere University Hospital, Tampere, Finland
- Medical School, University of Tampere, Tampere, Finland
| | - Patrick S. Daugherty
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
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Zhang S, Long A, Link AJ. A comparison of two strategies for affinity maturation of a BH3 peptide toward pro-survival Bcl-2 proteins. ACS Synth Biol 2012; 1:89-98. [PMID: 23651073 DOI: 10.1021/sb200002m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The Bcl-2 family of proteins regulates apoptosis at the level of mitochondrial permeabilization. Pro-death members of the family, including Bak and Bax, initiate apoptosis, whereas pro-survival members such as Bcl-x(L) and Mcl-1 antagonize the function of Bak and Bax via heterodimeric interactions. These heterodimeric interactions are primarily mediated by the binding of the helical amphipathic BH3 domain from a pro-death protein to a hydrophobic cleft on the surface of the pro-survival protein. Since high levels of pro-survival Bcl-2 proteins are present in many cancers, peptides corresponding to pro-death BH3 domains hold promise as therapeutics. Here we apply a high-throughput flow cytometry assay to engineer the Bak BH3 domain for improved affinity toward the pro-survival proteins Bcl-x(L) and Mcl-1. Two strategies, engineering the hydrophobic face of the Bak BH3 peptide and increasing its overall helicity, are successful in identifying Bak BH3 variants with improved affinity to Bcl-x(L) and Mcl-1. Hydrophobic face engineering of the Bak BH3 peptide led to variants with up to a 15-fold increase in affinity for Bcl-x(L) and increased specificity toward Bcl-x(L). Engineering of the helicity of Bak BH3 led to modest (3- to 4-fold) improvements in affinity with retention of promiscuous binding to all pro-survival proteins. HeLa cell killing studies demonstrate that the affinity matured Bak BH3 variants retain their expected biological function.
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Affiliation(s)
- Siyan Zhang
- Departments of †Chemical and Biological Engineering and ‡Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Angel Long
- Departments of †Chemical and Biological Engineering and ‡Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - A. James Link
- Departments of †Chemical and Biological Engineering and ‡Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
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Abstract
Peptides are increasingly used as therapeutic and diagnostic agents. The combination of bacterial cell-surface display peptide libraries with magnetic- and fluorescence-activated cell sorting technologies provides an efficient and highly effective methodology to identify and engineer peptides for a growing number of molecular recognition applications. Here, detailed protocols for both the generation and screening of bacterial display peptide libraries are presented. The methods described enable the discovery and evolutionary optimization of protein-binding peptides, cell-specific peptides, and enzyme substrates for diverse biotechnology applications.
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Affiliation(s)
- Jennifer A Getz
- Department of Chemical Engineering, Institute for Collaborative Biotechnologies, University of California, Santa Barbara, California, USA
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Reynolds F, Kelly KA. Techniques for molecular imaging probe design. Mol Imaging 2011; 10:407-419. [PMID: 22201532 PMCID: PMC3224676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
Molecular imaging allows clinicians to visualize disease-specific molecules, thereby providing relevant information in the diagnosis and treatment of patients. With advances in genomics and proteomics and underlying mechanisms of disease pathology, the number of targets identified has significantly outpaced the number of developed molecular imaging probes. There has been a concerted effort to bridge this gap with multidisciplinary efforts in chemistry, proteomics, physics, material science, and biology--all essential to progress in molecular imaging probe development. In this review, we discuss target selection, screening techniques, and probe optimization with the aim of developing clinically relevant molecularly targeted imaging agents.
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Affiliation(s)
- Fred Reynolds
- Robert M. Berne Cardiovascular Research Center and Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
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48
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Kogot JM, Zhang Y, Moore SJ, Pagano P, Stratis-Cullum DN, Chang-Yen D, Turewicz M, Pellegrino PM, de Fusco A, Soh HT, Stagliano NE. Screening of peptide libraries against protective antigen of Bacillus anthracis in a disposable microfluidic cartridge. PLoS One 2011; 6:e26925. [PMID: 22140433 PMCID: PMC3225367 DOI: 10.1371/journal.pone.0026925] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/05/2011] [Indexed: 11/21/2022] Open
Abstract
Bacterial surface peptide display has gained popularity as a method of affinity reagent generation for a wide variety of applications ranging from drug discovery to pathogen detection. In order to isolate the bacterial clones that express peptides with high affinities to the target molecule, multiple rounds of manual magnetic activated cell sorting (MACS) followed by multiple rounds of fluorescence activated cell sorting (FACS) are conventionally used. Although such manual methods are effective, alternative means of library screening which improve the reproducibility, reduce the cost, reduce cross contamination, and minimize exposure to hazardous target materials are highly desired for practical application. Toward this end, we report the first semi-automated system demonstrating the potential for screening bacterially displayed peptides using disposable microfluidic cartridges. The Micro-Magnetic Separation platform (MMS) is capable of screening a bacterial library containing 3 × 10¹⁰ members in 15 minutes and requires minimal operator training. Using this system, we report the isolation of twenty-four distinct peptide ligands that bind to the protective antigen (PA) of Bacilus anthracis in three rounds of selection. A consensus motif WXCFTC was found using the MMS and was also found in one of the PA binders isolated by the conventional MACS/FACS approach. We compared MMS and MACS rare cell recovery over cell populations ranging from 0.1% to 0.0000001% and found that both magnetic sorting methods could recover cells down to 0.0000001% initial cell population, with the MMS having overall lower standard deviation of cell recovery. We believe the MMS system offers a compelling approach towards highly efficient, semi-automated screening of molecular libraries that is at least equal to manual magnetic sorting methods and produced, for the first time, 15-mer peptide binders to PA protein that exhibit better affinity and specificity than peptides isolated using conventional MACS/FACS.
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Affiliation(s)
- Joshua M. Kogot
- United States Army Research Laboratory, Sensors and Electron Devices Directorate, Adelphi, Maryland, United States of America
| | - Yanting Zhang
- Cynvenio Biosystems, Inc., Westlake Village, California, United States of America
| | - Stephen J. Moore
- CytomX Therapeutics, LLC, Santa Barbara, California, United States of America
| | - Paul Pagano
- Cynvenio Biosystems, Inc., Westlake Village, California, United States of America
| | - Dimitra N. Stratis-Cullum
- United States Army Research Laboratory, Sensors and Electron Devices Directorate, Adelphi, Maryland, United States of America
| | - David Chang-Yen
- Cynvenio Biosystems, Inc., Westlake Village, California, United States of America
| | - Marek Turewicz
- Cynvenio Biosystems, Inc., Westlake Village, California, United States of America
| | - Paul M. Pellegrino
- United States Army Research Laboratory, Sensors and Electron Devices Directorate, Adelphi, Maryland, United States of America
| | - Andre de Fusco
- Cynvenio Biosystems, Inc., Westlake Village, California, United States of America
| | - H. Tom Soh
- Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Nancy E. Stagliano
- CytomX Therapeutics, LLC, Santa Barbara, California, United States of America
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Abstract
Molecular imaging allows clinicians to visualize disease-specific molecules, thereby providing relevant information in the diagnosis and treatment of patients. With advances in genomics and proteomics and underlying mechanisms of disease pathology, the number of targets identified has significantly outpaced the number of developed molecular imaging probes. There has been a concerted effort to bridge this gap with multidisciplinary efforts in chemistry, proteomics, physics, material science, and biology—all essential to progress in molecular imaging probe development. In this review, we discuss target selection, screening techniques, and probe optimization with the aim of developing clinically relevant molecularly targeted imaging agents.
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Affiliation(s)
- Fred Reynolds
- From the Robert M. Berne Cardiovascular Research Center and the Department of Biomedical Engineering, University of Virginia, Charlottesville, VA. Reprints not available
| | - Kimberly A. Kelly
- From the Robert M. Berne Cardiovascular Research Center and the Department of Biomedical Engineering, University of Virginia, Charlottesville, VA. Reprints not available
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50
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Löfblom J. Bacterial display in combinatorial protein engineering. Biotechnol J 2011; 6:1115-29. [DOI: 10.1002/biot.201100129] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/15/2011] [Accepted: 06/20/2011] [Indexed: 12/17/2022]
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