Isabel Usón

Institut de Biologia Molecular de Barcelona (CSIC - IBMB)

Life & Medical Sciences

Isabel Usón Finkenzeller completed a Chemistry degree (1987) and Ph. D. (1992) in synthetic organometallic chemistry at the U. of Zaragoza. In November 1992, she joined Procter & Gamble as Product Research Scientist in Brussels, gaining insight into the science and management of industrial chemistry. She moved as HCM postdoc to the U. of Göttingen in 1994. She has developed methods for crystallography for 23 years, first within the group of Prof. Sheldrick FRS, author of SHELX, during her postdoctoral research and Habilitation (1994-2001) and as of July 2001 leading an emergent group. September 2003, she moved to Barcelona as ICREA Research Professor. Her work on structural chemistry and biology has led to over 135 publications. The software ARCIMBOLDO is the central output of her work. She is one of the seven members of the Maria de Maeztu Excellence Unit of Structural Biology at the IBMB-CSIC.

Research interests

Macromolecular crystallography provides conclusive structural information down to atomic detail and has been inextricable from major advances in the life sciences. Nevertheless, this structural model cannot be directly calculated from the experimental data, as we cannot measure the phases of the diffracted X-ray beams. Our group develops methods to exploit the stereochemical knowledge present in small, accurate units such as secondary structure fragments and their association into local folds. Their use to solve the central phase problem of crystallography is implemented in our software ARCIMBOLDO. This has required devising our own particular toolbox for fragments. We are extending this detailed view to map interpretation within the program SHELXE (Sheldrick) and general structure interpretation within our program BORGES_MATRIX. As illustrated in paintings by G. Arcimboldo, the information content derived from a correct combination of fragments goes beyond their simple addition.

Selected publications

– Osman D, Piergentili C, Chen J, Sayer LN, Usón I, Huggins TG, Robinson NJ & Pohl E 2016, ‘The Effectors and Sensory Sites of Formaldehyde-Responsive Regulator FrmR and Metal-Sensing Variant’, J. Biol. Chem., 291(37):19502-16.

– Fedosyuk S, Bezerra GA, Radakovics K, Smith TK, Sammito M, Bobik N et al. 2016, ‘Vaccinia Virus Immunomodulator A46: A Lipid and Vaccinia Virus Immunomodulator A46: A Lipid and Protein-Binding Scaffold for Sequestering Host TIR-Domain Proteins’, PLOS Pathogens, 12(12):e1006079.

Selected research activities

– Release of the ARCIMBOLDO programs within the main European consortium for crystallographic software, CCP4 in January 2016, further integration and extension of the CCP4 version along the year.

– Release of a new ARCIMBOLDO_SHREDDER in December 2016.

– Release of coauthored SHELXE beta version.

– Sabbatical research stay at the CIMR, University of Cambridge.

– Member of the management board for the construction of the XAIRA microfocus beamline at ALBA.