Ann M. Valentine

Associate Professor of Chemistry
Member of Yale faculty since 2001

E-mail: ann.valentine@yale.edu
Web site: http://xbeams.chem.yale.edu/~valentine

Research Our research in bioinorganic chemistry focuses on biologically relevant metals that are very sensitive to hydrolysis – mainly iron and titanium – and addresses how biology handles these difficult metals. Problems relate to metal uptake and transport, potential therapeutic applications thereof, and biomineralization.

Nicatransferrin We are working to characterize the monolobal transferrin from marine invertebrate chordates called ascidians, partly to understand better how nature evolved the capacity to manage very hydrolysis-prone metals.

Biologically and Environmentally Relevant Titanium Coordination Chemistry Doing Ti(IV) chemistry in water at neutral pH is tough because Ti(IV) hydrolyzes so easily. We make and characterize complexes using ligands relevant to the coordination of Ti(IV) in biology and/or the environment.

Titanium and Biomolecules Titanium(IV) is a bioactive metal ion, and Ti(IV)-containing molecules have been promising as anticancer drugs. We are characterizing the interactions between titanium ions and biomolecules to explore the nature of this bioactivity, and to exploit it for human benefit.

Biotitanification We have looked at whole organisms and worked with biomolecules modeling those found in diatoms, to understand the controlled mineraliztion of titanium.

Education
B.S. University of Virginia, 1993
Ph.D. Massachusetts Institute of Technology, 1998
Postdoctoral Fellow, Penn State University, 1998-2001

Honors
Research Corporation Research Innovation Award, 2003
NSF CAREER Award, 2004
American Cancer Society Research Scholar Award, 2006
American Chemical Society PROGRESS/Dreyfus Lectureship Award, 2007
Paul Saltman Award for Metals in Biology, 2009

Recent Publications
J.M. Collins, R. Uppal, C.D. Incarvito, & A.M. Valentine. Titanium(IV) Citrate Speciation and Structure under Environmentally and Biologically Relevant Conditions. Inorg. Chem. 2005, 44, 3431-3440.

K.E. Cole, A.N. Ortiz, M.A. Schoonen, & A.M. Valentine. Peptide- and Long-Chain Polyamine- Induced Synthesis of Micro- and Nanostructured Titanium Phosphates. Chem. Mater. 2006, 18, 4592-4599.

R. Uppal, C.D. Incarvito, K.V. Lakshmi, & A.M. Valentine. Aqueous Spectroscopy and Redox Properties of Carboxylate-Bound Titanium. Inorg. Chem. 2006, 45, 1795-1804.

A.D. Tinoco, E.A. Eames, & A.M. Valentine. Reconsideration of Serum Ti(IV) Transport: Albumin and Transferrin Trafficking of Ti(IV) and Its Complexes. J. Am. Chem. Soc. 2008, 130, 2262-2270.

A.D. Tinoco, C.W. Peterson, B. Lucchese, R.P. Doyle, & A.M. Valentine. On the Evolutionary Significance and Metal-binding Characteristics of a Monolobal Transferrin from Ciona intestinalis. Proc. Natl. Acad. Sci. USA 2008, 105, 3268-3273. (Faculty of 1000 Recommended Paper)

Ann M. Valentine

Research Interests