About

David Wood is an adjunct professor in the Department of Chemistry and Biochemistry at The Ohio State University. He holds a B.S. in Biology and Chemical Engineering from the California Institute of Technology, obtained in 1990, an M.S. in Chemical Engineering from Rensselaer Polytechnic Institute earned in 1997, and a Ph.D. from Rensselaer Polytechnic Institute completed in 1999. His research focuses on applied protein engineering for biotechnology development, aiming to develop highly useful biotechnologies through engineering proteins and enzymes for specific applications. His work includes developing new methods for protein purification, such as self-cleaving affinity tags that facilitate large-scale bioprocessing, and creating biosensors for detecting human hormone-like compounds. These biosensors utilize chimeric fusion proteins with engineered ligand-binding domains, capable of detecting and discriminating between various hormone activities, and are designed to be adaptable for screening natural product libraries. His contributions also extend to understanding the structure, energy, and kinetics of engineered proteins, with the goal of generating new rules for engineering allosteric protein chimeras.

Research topics

• Medicine
• Chemistry
• Biochemistry
• Computer science
• Biology

Selected publications

• Novel Self-Cleaving Affinity Purification Method for Cellular Membrane-Associated Recombinant Paraoxonase-1 (rePON1) Enzyme

  The Protein Journal · 2025-06-02

  articleOpen accessSenior author

  Mammalian paraoxonase-1 (PON1) is a ~ 39.45 kDa calcium-dependent hydrolytic enzyme with potential therapeutic applications in chemical defense and cardiovascular disease. The N-terminus of PON1 is embedded in the cellular membrane, imparting to a hydrophobic character that leads to increased aggregation propensity and instability during purification. Although some advances have been made in bacterial expression hosts by using solubility-enhancing fusion tags and detergent solubilization strategies, these studies have shown that proteolytic tag removal is generally problematic. Thus, ineffective tag removal limits the bioanalytical characterization of the enzyme. Furthermore, the need for stabilizing detergents during purification limits the options for affinity-tag based methods. In this study, we demonstrate a novel affinity purification strategy by combining two solubility-enhancing fusion partners with the iCapTag™ self-removing affinity tag, where the entire purification process takes place in the presence of detergent. Optimization of purification conditions, including detergent and pH, resulted in the successful solubilization and stabilization of rePON1 at room temperature, allowing the tagless and native protein to be characterized. The results confirmed the expected catalytic efficiency and molecular weight of the enzyme. This method achieved over 95% host-cell protein impurities and more than 99.9% clearance of the host cell's double-stranded DNA in a single-column affinity operation. This approach combines the power of affinity chromatography and facile tag removal, thereby offering a versatile and efficient alternative to produce other recombinant membrane-associated proteins, as well as additional target proteins that require challenging buffer conditions.

  PublisherOA PDFDOI

• Controllable intein splicing and N-terminal cleavage at mesophilic temperatures

  Frontiers in Bioengineering and Biotechnology · 2025-02-07

  articleOpen access

  Inteins (intervening proteins) interrupt host proteins and are removed through a protein splicing reaction that ligates adjacent N- and C-exteins. The ability of inteins to specifically rearrange peptide bonds has proven exceptionally useful in protein engineering, thus, methods to control intein activity are of considerable interest. One particularly useful application of inteins is for the removal of an affinity tag following purification of a target protein through N-terminal cleavage (NTC). Typically, extended incubation at high temperature (greater than 50°C) or with an external nucleophile (e.g., dithiothreitol) is required to drive NTC, conditions that compromise the folding of many target proteins. Here, we characterize a variant of the Thermococcus kodakarensis RadA intein that can perform NTC at moderate temperatures in the absence of an external nucleophile. While we find that while NTC is largely inhibited during expression in Escherichia coli at 15°C, rapid and efficient NTC can be activated 37°C. Our results provide an alternative intein-based system – one that does not require either an external nucleophile or prolonged incubation at high temperature to stimulate NTC – that controls intein activity within a temperature range amenable to most mesophilic experimental organisms.

  PublisherOA PDFDOI

• TCT-305 The Landmark RESPECT Results Reaffirmed with Real-World Procedural and Safety Outcomes of Patent Foramen Ovale (PFO) Closure Using the AmplatzerTM PFO and AmplatzerTM TalismanTM Occluders

  Journal of the American College of Cardiology · 2025-10-01

  article
  PublisherDOI

• Application of natively expressed chitinase as a sustainable fungal bioshield

  Enzyme and Microbial Technology · 2025-07-29 · 1 citations

  articleOpen accessSenior authorCorresponding

  Postharvest losses of fruits and vegetables due to fungal spoilage pose a significant challenge, compounded by growing consumer concerns about the harmful effects of chemical fungicides and the limited effectiveness of traditional food coatings (such as wax and biopolymer formulations) in controlling microorganisms, particularly fungi. In this study, we developed a formulation-free method using a non-modified chitinase from a thermostable strain of Bacillus cereus isolated from soil. The purified chitinase inhibited in vitro mycelium growth of four food-pathogenic fungi: Penicillium digitatum , Neurospora crassa , Aspergillus fumigatus , and Alternaria alternata . Furthermore, when applied directly on strawberry and onion tissue, the purified chitinase inhibited Aspergillus fumigatus and A. niger colonization of the produce. This demonstrates the addition of chitinase provides a cost-effective and non-toxic alternative as a bio-active food coating material to prevent fungal fruit and vegetable spoilage and extend food shelf life. • Bioactive food covering effectively prevents fungal rot in fruit (strawberry) and vegetable (onion). • Enhanced chitinase production using optimized media supplemented with biowaste (rice straw, crab, and shrimp shell wastes). • Effective biocontrol of four food pathogenic fungi (Penicillium digitatum, Neurospora crassa, Aspergillus fumigatus, and Alternaria alternata). • Scaled production to 4 liters facilitating industrial efficiency.

  PublisherDOI

• Improved self-cleaving precipitation tags for efficient column free bioseparations

  Protein Expression and Purification · 2024-08-15 · 6 citations

  articleSenior authorCorresponding
  PublisherDOI

• Scalable dual column cation exchange affinity chromatography based platform process for recombinant protein purification

  Protein Expression and Purification · 2024-02-07 · 4 citations

  articleSenior authorCorresponding
  PublisherDOI

• Highly selective split intein method for efficient separation and purification of recombinant therapeutic proteins from mammalian cell culture fluid

  Journal of Chromatography A · 2024-10-09 · 6 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Inteins—mechanism of protein splicing, emerging regulatory roles, and applications in protein engineering

  Frontiers in Microbiology · 2023-11-08 · 29 citations

  reviewOpen access1st author

  Protein splicing is a posttranslational process in which an intein segment excises itself from two flanking peptides, referred to as exteins. In the native context, protein splicing results in two separate protein products coupled to the activation of the intein-containing host protein. Inteins are generally described as either full-length inteins, mini-inteins or split inteins, which are differentiated by their genetic structure and features. Inteins can also be divided into three classes based on their splicing mechanisms, which differ in the location of conserved residues that mediate the splicing pathway. Although inteins were once thought to be selfish genetic elements, recent evidence suggests that inteins may confer a genetic advantage to their host cells through posttranslational regulation of their host proteins. Finally, the ability of modified inteins to splice and cleave their fused exteins has enabled many new applications in protein science and synthetic biology. In this review, we briefly cover the mechanisms of protein splicing, evidence for some inteins as environmental sensors, and intein-based applications in protein engineering.

  PublisherOA PDFDOI

• Streamlining the Detection of Human Thyroid Receptor Ligand Interactions with XL1-Blue Cell-Free Protein Synthesis and Beta-Galactosidase Fusion Protein Biosensors

  Life · 2023-09-27 · 2 citations

  articleOpen access

  Thyroid receptor signaling controls major physiological processes and disrupted signaling can cause severe disorders that negatively impact human life. Consequently, methods to detect thyroid receptor ligands are of great toxicologic and pharmacologic importance. Previously, we reported thyroid receptor ligand detection with cell-free protein synthesis of a chimeric fusion protein composed of the human thyroid receptor beta (hTRβ) receptor activator and a β-lactamase reporter. Here, we report a 60% reduction in sensing cost by reengineering the chimeric fusion protein biosensor to include a reporter system composed of either the full-length beta galactosidase (β-gal), the alpha fragment of β-gal (β-gal-α), or a split alpha fragment of the β-gal (split β-gal-α). These biosensor constructs are deployed using E. coli XL1-Blue cell extract to (1) avoid the β-gal background activity abundant in BL21 cell extract and (2) facilitate β-gal complementation reporter activity to detect human thyroid receptor ligands. These results constitute a promising platform for high throughput screening and potentially the portable detection of human thyroid receptor ligands.

  PublisherOA PDFDOI

• A Convenient Self‐Removing Affinity Tag Method for the Simple Purification of Tagless Recombinant Proteins

  Current Protocols · 2023-10-01 · 9 citations

  articleOpen accessSenior authorCorresponding

  , the N-terminal segment of an engineered split intein is covalently immobilized onto a capture resin, while the smaller C-terminal intein segment is fused to the N-terminus of the desired target protein. The tagged target can then be expressed in an appropriate expression system, without concern for premature intein cleaving. During the purification, strong binding between the intein segments effectively captures the tagged target onto the capture resin while simultaneously generating a cleaving-competent intein complex. After unwanted impurities are washed from the resin, cleavage of the target protein is initiated by a shift of the buffer pH from 8.5 to 6.2. As a result, the highly purified tagless target protein is released from the column in the elution step. Alternately, the resin beads can be added directly to cell culture broth or lysate, allowing capture, purification and cleavage of the tagless target protein using a column-free format. These methods result in highly pure tagless target protein in a single step, and can thereby accelerate characterization and functional studies. In this work we demonstrate the single step purification of streptokinase, a fibrinolytic agent, and an engineered recombinant human hemoglobin 1.1 (rHb1.1). © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Expression of high-titer protein tagged with the Nostoc punctiforme (Npu) DnaE split-intein on the N-terminus Basic Protocol 2: Purification of high-titer protein using the Nostoc punctiforme (Npu) DnaE split-intein purification platform Alternate Protocol 1: Expression of low-titer protein tagged with the Nostoc punctiforme (Npu) DnaE split-intein on the N-terminus Alternate Protocol 2: Purification of low-titer protein using the Nostoc punctiforme (Npu) DnaE split-intein purification platform.

  PublisherOA PDFDOI

Recent grants

• Highly Controllable Self-cleaving Tags for Biopharmaceutical Research and Manufacturing Purification Platforms

  NSF · $240k · 2013–2017

• Engineering a novel biomaterial for oxygen transport applications

  NIH · $2.5M · 2021–2025

• NIH Grant R21ES016630

  NIH · $402k · 2012

• CAREER: Protein Switches for Molecular Biotechnology

  NSF · $12k · 2009–2010

• CAREER: Protein Switches for Molecular Biotechnology

  NSF · $400k · 2004–2010

Frequent coauthors

• Marlene Belfort

  University at Albany, State University of New York

  60 shared

• Victoria Derbyshire

  Howard Hughes Medical Institute

  59 shared

• John T. Dansereau

  Wadsworth Center

  36 shared

• Wei Wu

  36 shared

• Harold I. Lecks

  Children's Hospital of Philadelphia

  36 shared

• Jacob Z. Dalgaard

  36 shared

• John J. Downes

  University of Sydney

  24 shared

• Lillian P. Kravis

  University of Pennsylvania

  20 shared

Awards & honors

• John S. Swenton Award for Outstanding Teaching
• William Lloyd Evans Lecture
• Devon W. Meek Lecture
• Edward Mack, Jr. Lecture
• Leo Paquette Legacy Symposium