About

J. Herbert Waite is a Distinguished Professor in the Department of Chemistry & Biochemistry at the University of California, Santa Barbara. His research focuses on understanding how marine organisms such as barnacles, limpets, kelps, and mussels produce underwater adhesives that function effectively in wet environments. He investigates the chemical and physical mechanisms of biological attachment, with particular emphasis on mussel byssal threads, which serve as permanent holdfasts and are notable for their strength, rapid formation, durability, and ability to adhere to various surfaces including glass, metal, paraffin, and bone. Waite's work involves characterizing proteins from the different functional domains of the byssus, which is a complex composite material. His research has uncovered exotic proteins previously locked in cross-linked networks by studying the effects of cold temperature shocks on mussels. He employs techniques such as protein chemistry, molecular biology, laser mass spectrometry, solid-state NMR, and atomic force microscopy to analyze protein sequences, structures, and behaviors. His ultimate goal is to process these proteins into useful applications that mimic their natural functions in mussels, contributing to advancements in biomimetic adhesives and coatings.

Research topics

• Chemistry
• Materials science
• Biochemistry
• Biology
• Nanotechnology

Selected publications

• The Calicophoron daubneyi genome provides new insight into mechanisms of feeding, eggshell synthesis and parasite-microbe interactions

  BMC Biology · 2025-01-13 · 4 citations

  articleOpen access

  BACKGROUND: The rumen fluke, Calicophoron daubneyi, is the major paramphistome species infecting ruminants within Europe. Adult flukes reside within the rumen where they are in direct contact with a unique collection of microorganisms. Here, we report a 1.76-Gb draft genome for C. daubneyi, the first for any paramphistome species. RESULTS: Several gene families have undergone specific expansion in C. daubneyi, including the peptidoglycan-recognition proteins (PGRPs) and DM9 domain-containing proteins, which function as pattern-recognition receptors, as well as the saposin-like proteins with putative antibacterial properties, and are upregulated upon arrival of the fluke in the microbe-rich rumen. We describe the first characterisation of a helminth PGRP and show that a recombinant C. daubneyi PGRP binds to the surface of bacteria, including obligate anaerobes from the rumen, via specific interaction with cell wall peptidoglycan. We reveal that C. daubneyi eggshell proteins lack L-DOPA typically required for eggshell crosslinking in trematodes and propose that C. daubneyi employs atypical eggshell crosslinking chemistry that produces eggs with greater stability. Finally, although extracellular digestion of rumen ciliates occurs within the C. daubneyi gut, unique ultrastructural and biochemical adaptations of the gastrodermal cells suggest that adult flukes also acquire nutrients via uptake of volatile fatty acids from rumen fluid. CONCLUSIONS: Our findings suggest that unique selective pressures, associated with inhabiting a host environment so rich in microbial diversity, have driven the evolution of molecular and morphological adaptations that enable C. daubneyi to defend itself against microorganisms, feed and reproduce within the rumen.

  PublisherOA PDFDOI

• Catechol redox maintenance in mussel adhesion

  Nature Reviews Chemistry · 2025-01-15 · 68 citations

  reviewOpen accessSenior author
  PublisherOA PDFDOI

• Coacervate Phase Evolution and Membrane Formation in Natural Seawater

  Journal of the American Chemical Society · 2024-01-11 · 8 citations

  articleOpen accessCorresponding

  Marine organisms produce biological materials through the complex self-assembly of protein condensates in seawater, but our understanding of the mechanisms of microstructure evolution and maturation remains incomplete. Here, we show that critical processing attributes of mussel holdfast proteins can be captured by the design of an amphiphilic, fluorescent polymer (PECHIA) consisting of a polyepichlorohydrin backbone grafted with 1-imidazolium acetonitrile. Aqueous solutions of PECHIA were extruded into seawater, wherein the charge repulsion of PECHIA is screened by high salinity, facilitating interfacial condensation via enhanced "cation-dipole" interactions. Diffusion of seawater into the PECHIA solution caused droplets to form immiscibly within the PECHIA phase (i.e., inverse coacervation). Simultaneously, weakly alkaline seawater catalyzes nitrile cyclization and time-dependent solidification of the PECHIA phase, leading to hierarchically porous membranes analogous to porous architectures in mussel plaques. In contrast to conventional polymer processing technologies, processing of this biomimetic polymer required neither organic solvents nor heating and enabled the template-free production of hollow spheres and fibers over a wide range of salinities.

  PublisherOA PDFDOI

• Compliant Clients: Catechols Exhibit Enhanced Solubility and Stability in Diverse Complex Coacervates

  Biomacromolecules · 2023-08-21 · 10 citations

  articleOpen accessCorresponding

  Polyelectrolyte coacervates, with their greater-than-water density, low interfacial energy, shear thinning viscosity, and ability to undergo structural arrest, mediate the formation of diverse load-bearing macromolecular materials in living organisms as well as in industrial material fabrication. Coacervates, however, have other useful attributes that are challenging to study given the metastability of coacervate colloidal droplets and a lack of suitable analytical methods. We adopt solution electrochemistry and nuclear magnetic resonance measurements to obtain remarkable insights about coacervates as solvent media for low-molecular-weight catechols. When catechols are added to dispersions of coacervated polyelectrolytes, there are two significant consequences: (1) catechols preferentially partition up to 260-fold into the coacervate phase, and (2) coacervates stabilize catechol redox potentials by up to +200 mV relative to the equilibrium solution. The results suggest that the relationship between phase-separated polyelectrolytes and their client molecules is distinct from that existing in aqueous solution and has the potential for insulating many redox-unstable chemicals.

  PublisherOA PDFDOI

• Mechanical Behavior of Octopus Egg Tethers Composed of Topologically Constrained, Tandemly Repeated EGF Domains

  Biomacromolecules · 2023-06-09 · 4 citations

  articleOpen accessSenior authorCorresponding

  Whether and how intramolecular crosslinks in polymeric materials contribute to mechanical properties is debated in both experimental and theoretical arenas. The tethering threads of Octopus bimaculoides egg cases provide a rare window to investigate this question in a biomaterial. The only detectable component of the load-bearing fibers in octopus threads is a 135 kDa protein, octovafibrin, comprising 29 tandem repeats of epidermal growth factor (EGF) each of which contains 3 intramolecular disulfide linkages. The N- and C-terminal C-type lectins mediate linear end-to-end octovafibrin self-assembly. Mechanical testing of threads shows that the regularly spaced disulfide linkages result in improved stiffness, toughness, and energy dissipation. In response to applied loads, molecular dynamics and X-ray scattering show that EGF-like domains deform by recruiting two hidden length β-sheet structures nested between the disulfides. The results of this study further the understanding of intramolecular crosslinking in polymers and provide a foundation for the mechanical contributions of EGF domains to the extracellular matrix.

  PublisherOA PDFDOI

• Essential Role of Thiols in Maintaining Stable Catecholato-Iron Complexes in Condensed Materials

  Chemistry of Materials · 2022-05-19 · 18 citations

  articleOpen accessCorresponding

  The load-bearing proteins in mussel holdfasts rely on condensed tris-catecholato-Fe3+ coordination complexes for their toughness and shock-absorbing properties, and this feature has been successfully translated into synthetic materials with short-term high-performance properties. However, oxidation of catecholic DOPA (3,4-dihydroxyphenylalanine) remains a critical impediment to achieving materials with longer-lasting performance. Here, following the natural mussel pathway for protein processing, we explore how DOPA oxidation impacts coacervation of mussel foot protein-1 (mfp-1) and its capacity for phase-specific metal uptake in vitro. Without metal, DOPA oxidation changed the rheological properties (i.e., viscosity, loss, and storage moduli) of mfp-1 coacervate droplets. However, oxidation-dependent changes were recovered with dithiothreitol (DTT), completely restoring the behavior of mfp-1 coacervates prior to oxidation. With metal, mfp-1 coacervates exhibited gel-like behavior with high viscosity and cohesive forces by forming recognizable bis- and tris-catecholato-Fe complexes, linked to increased energy dissipation and toughness of byssus. These results indicate that Fe3+-mediated conversion of liquid–liquid phase-separated polymers into metal-coordinated networks is thorough and rapid, and DTT effectively maintains redox integrity. Our study provides much-needed improvements for processing catechol-functionalized polymers into high-performance materials.

  PublisherOA PDFDOI

• A multi-tasking polypeptide from bloodworm jaws: Catalyst, template, and copolymer in film formation

  Matter · 2022-04-25 · 17 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Nanolattice-Forming Hybrid Collagens in Protective Shark Egg Cases

  Biomacromolecules · 2022-06-24 · 3 citations

  articleOpen accessSenior authorCorresponding

  Nanoscopic structural control with long-range ordering remains a profound challenge in nanomaterial fabrication. The nanoarchitectured egg cases of elasmobranchs rely on a hierarchically ordered latticework for their protective function─serving as an exemplary system for nanoscale self-assembly. Although the proteinaceous precursors are known to undergo intermediate liquid crystalline phase transitions before being structurally arrested in the final nanolattice architecture, their sequences have so far remained unknown. By leveraging RNA-seq and proteomic techniques, we identified a cohort of nanolattice-forming proteins comprising a collagenous midblock flanked by domains typically associated with innate immunity and network-forming collagens. Structurally homologous proteins were found in the genomes of other egg-case-producing cartilaginous fishes, suggesting a conserved molecular self-assembly strategy. The identity and stabilizing role of cross-links were subsequently elucidated using mass spectrometry and in situ small-angle X-ray scattering. Our findings provide a new design approach for protein-based liquid crystalline elastomers and the self-assembly of nanolattices.

  PublisherOA PDFDOI

• Viscoelastic analysis of mussel threads reveals energy dissipative mechanisms

  Journal of The Royal Society Interface · 2022-03-01 · 11 citations

  articleOpen accessSenior authorCorresponding

  Mussels use byssal threads to secure themselves to rocks and as shock absorbers during cyclic loading from wave motion. Byssal threads combine high strength and toughness with extensibility of nearly 200%. Researchers attribute tensile properties of byssal threads to their elaborate multi-domain collagenous protein cores. Because the elastic properties have been previously scrutinized, we instead examined byssal thread viscoelastic behaviour, which is essential for withstanding cyclic loading. By targeting protein domains in the collagenous core via chemical treatments, stress relaxation experiments provided insights on domain contributions and were coupled with in situ small-angle X-ray scattering to investigate relaxation-specific molecular reorganizations. Results show that when silk-like domains in the core were disrupted, the stress relaxation of the threads decreased by nearly 50% and lateral molecular spacing also decreased, suggesting that these domains are essential for energy dissipation and assume a compressed molecular rearrangement when disrupted. A generalized Maxwell model was developed to describe the stress relaxation response. The model predicts that maximal damping (energy dissipation) occurs at around 0.1 Hz which closely resembles the wave frequency along the California coast and implies that these materials may be well adapted to the cyclic loading of the ambient conditions.

  PublisherOA PDFDOI

• Data and Code_Viscoelastic analysis of mussel threads reveals energy dissipative mechanisms.zip

  Figshare · 2022-01-01

  datasetOpen access

  The data and code presented here was used to obtain results presented in the article 'Viscoelastic analysis of mussel threads reveals energy dissipative mechanisms' by Marcela Areyano, Eric Valois, Ismael Carvajal Sanchez, Ivan Rajkovic, William R. Wonderly, Attila Kossa, Robert M. Mcmeeking, and J. Herbert Waite.

  PublisherDOI

Recent grants

• Transating Mussel Adhesion

  NIH · $4.2M · 2008–2019

• NIH Grant R01DE010042

  NIH · $2.1M · 2005

• NIH Grant R01DE014672

  NIH · $2.5M · 2008

• NIH Grant R22AI024450

  NIH · $232k · 1989

• NIH Grant R01DE005956

  NIH · $60k · 1986

Frequent coauthors

• Jacob N. Israelachvili

  45 shared

• Galen D. Stucky

  University of California, Santa Barbara

  27 shared

• Megan T. Valentine

  University of California, Santa Barbara

  25 shared

• Leszek M. Rzepecki

  22 shared

• Emmanouela Filippidi

  University of Crete

  22 shared

• Dong Soo Hwang

  19 shared

• Douglas C. Hansen

  University of Dayton

  18 shared

• Henrik Birkedal

  Aarhus University

  18 shared

Education

• PhD Biochemistry, Zoology

  Duke University

  1976

• Batchelors/Biology, Comparative Zoology

  Harvard University

  1971

Awards & honors

• PHS Service Award Fellow, University of Connecticut, 1978-19…