Physical Chemistry Seminar: Professor Alison Butler, University of California, Santa Barbara, Sapp Center Lecture Hall, 4:30pm (Host: Lynette Cegelski)
About the Seminar
“Metals, Marine Microbes and Mussels: the Chemical Biology of Siderophores and Surface Adhesion”
The bioinorganic chemistry of the marine environment reflects the chemical composition in which organisms evolve, survive and thrive. The transition metal ion composition of the surface ocean, differs remarkably from terrestrial environments. The most abundant transition metal ion in surface seawater is molybdenum followed by vanadium, and by contrast, iron is extremely low. Yet iron is essential to many marine organisms. Catechol ligands are also important, both as 2,3-dihydroxybenzoic acid present in certain siderophores used for Fe(III) uptake, and as 3,4-dihydroxyphenylalanine (DOPA) present in mussel foot proteins (mfps) for adhesion. In some mfps the catechol content is as high as 30 mol percent and matched by an equally high content of Lys or Arg. The siderophore cyclic trichrysobactin also has a matched ratio of catechol to Lys.
We recently discovered a synergistic role between cationic amines and catechols in surface adhesion to mica, in aqueous environments. Mica, an aluminosilicate mineral, develops a significant hydration layer in salt water. The cationic amine is important in displacement of hydrated surface cations, enabling catechol adhesion. In this talk new adhesive catechol compounds resembling siderophores and mussel foot proteins will be considered which further probe the importance of coupled catechol and cationic amine groups in aqueous wet adhesion. The coordination chemistry and biosynthesis of other siderophores will also be covered.
Adaptive synergy between catechol and lysine promotes wet adhesion by surface salt displacement, G.P. Maier, M.V. Rapp, J.H. Waite, J.N. Israelachvili, and Alison Butler, Science, 2015, 349, 628-632
Defining the Catechol-Cation Synergy for Enhanced Wet Adhesion to Mineral Surfaces M.V. Rapp, G.P. Maier, H.A. Dobbs, N.J. Higdon, J.H. Waite, Alison Butler, J.N. Israelachvili, J. Am. Chem. Soc., 2016, 138, 9013–9016.
Biosynthesis of Amphi-enterobactin Siderophores by Vibrio harveyi BAA-1116: Identification of a Bifunctional NRPS Condensation Domain, H.K. Zane, H. Naka, F. Rosconi, M. Sandy, M. G. Haygood and Alison Butler, J. Am. Chem. Soc., 2014, 134, 5615-5618
About the Speaker
Alison Butler joined the Department of Chemistry at UCSB in 1986, following postdoctoral fellowships at Caltech in Harry Gray’s laboratory and at UCLA in Joan Valentine’s laboratory. She majored in Chemistry as an undergraduate at Reed College and obtained a PhD at UC San Diego in the Department of Chemistry & Biochemistry with Robert G. Linck and Teddy G. Traylor.
Her research interests are in bioinorganic chemistry and metallobiochemistry, particularly elucidating roles of metal ions in catalysis by metalloenzymes, as well as processes by which microbes acquire metal ions they need to grow. Alison Butler’s research group is currently focusing on the biosynthesis and tailoring reactions of acylated siderophores in regards to microbial iron acquisition; the role of haloperoxidases in disruption of microbial quorum sensing, as well as in cryptic halogenation reactions; and the design of catechol compounds to investigate the role of catechols and cations in wet adhesion properties of mussels and microbes.