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Dra. Vanesa Galassi

 

-Assistant Researcher - CONICET Facultad de Ciencias Exactas y Naturales. Universidad Nacional de Cuyo.





Email: vanegalassi[at]gmail.com










Research Interests:

Voltage sensitive dyes (CSV) are widely used to determine membrane potential in imaging diagnosis field, and in scientific research. However, their application is limited by their sensibility and rate of response. 

There is a new family of dyes called VoltageFluor (VF), which mechanism of response relies on photo-induced electron transfer (PET), in which a photon absorption in the membrane core embedded moiety triggers the electron transfer through the molecule towards the surface, where a fluorescent group emits the output signal.


(A) Partition of a CSV in a lipid bilayer. The red line represents the free energy for the partition process F(z). (B) Scheme for PET the mechanism, responsible for voltage sensing. In VF molecules, anilin moiety (orange square) is electron donor, that transfer its electrons through the polyestyrene cable (black stick) upon photo-induction to the receptor fluoresceine (green square) (C) VF structure scheme. n is the number of estyrene units.


(A) Partition of a CSV in a lipid bilayer. The red line represents the free energy for the partition process F(z). (B) Scheme for PET the mechanism, responsible for voltage sensing. In VF molecules, anilin moiety (orange square) is electron donor, that transfer its electrons through the polyestyrene cable (black stick) upon photo-induction to the receptor fluoresceine (green square) (C) VF structure scheme. n is the number of estyrene units.










We aim at developing a thorough computational study for CSVs, ranging from the study of the partition of the molecular probe in the membrane to the simulation of the electron transfer process in order to reproduce and predict the fluorescent response when modifying the probe. This approach involves the use of atomistic classical potentials, hybrid potentials from quantum mechanics and molecular mechanics (QM/MM) and time-resolved electronic structure methods. The long-term objective is to develop a methodology that allows the study and optimization of CSVs.




Background:

2013-2016. Postdoctoral Fellow, Laboratório de Bioquímica e Biofísica Computacionais (LBBC) - Instituto de Química (IQ) da Universidade de Sao Paulo (USP).

2008-2013. Ph.D. in Chemistry, Facultad de Ciencias Químicas (FCQ) - Universidad Nacional de Córdoba (UNC) - Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC). Funding: CONICET.

2003-2008. B. Sc. in Chemistry, Facultad de Ciencias Químicas (FCQ) - Universidad Nacional de Córdoba (UNC).



Publications:

- V Galassi, V Nolan, MA Villarreal, M Perduca, HL Monaco, GG Montich. Kinetics of lipid-membrane binding and conformational change of L-BABP. Biochemical and biophysical research communications (2009) 382 (4), 771-775.

- MB Decca, VV Galassi, M Perduca, HL Monaco, GG Montich. Influence of the lipid phase state and electrostatic surface potential on the conformations of a peripherally bound membrane protein. The Journal of Physical Chemistry B (2010) 114 (46), 15141-15150.

- VV Galassi, MA Villarreal, V Posada, GG Montich. Interactions of the fatty acid-binding protein ReP1-NCXSQ with lipid membranes. Influence of the membrane electric field on binding and orientation. Biochimica et Biophysica Acta (BBA)-Biomembranes (2014) 1838 (3), 910-920.

- VV Galassi, GM Arantes. Partition, orientation and mobility of ubiquinones in a lipid bilayer. Biochimica et Biophysica Acta (BBA)-Bioenergetics (2015) 1847 (12), 1560-1573.