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About

About

With a degree in Pharmaceutical Sciences by the University of Coimbra (2001), a PhD in Computational Chemistry (FCUP, 2006), and a 6-year Post-Doc experience in Computational Biology in CIIMAR, I started working in INESC TEC in 2014, in Science Management, supporting the coordination of CRACS and LIAAD.

In March 2018, I was appointed Data Protection Officer of INESC TEC, a position that I held until January 2019.

Currently, I am the Data Protection Officer of the University of Porto.

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Details

Details

008
Publications

2013

Computational study of the covalent bonding of microcystins to cysteine residues - a reaction involved in the inhibition of the PPP family of protein phosphatases

Authors
Pereira, SR; Vasconcelos, VM; Antunes, A;

Publication
FEBS JOURNAL

Abstract
Microcystins (MCs) are cyclic peptides, produced by cyanobacteria, that are hepatotoxic to mammals. The toxicity mechanism involves the potent inhibition of protein phosphatases, as the toxins bind the catalytic subunits of five enzymes of the phosphoprotein phosphatase (PPP) family of serine/threonine-specific phosphatases: Ppp1 (aka PP1), Ppp2 (aka PP2A), Ppp4, Ppp5 and Ppp6. The interaction with the proteins includes the formation of a covalent bond with a cysteine residue. Although this reaction seems to be accessory for the inhibition of PPP enzymes, it has been suggested to play an important part in the biological role of MCs and furthermore is involved in their nonenzymatic conjugation to glutathione. In this study, the molecular interaction of microcystins with their targeted PPP catalytic subunits is reviewed, including the relevance of the covalent bond for overall inhibition. The chemical reaction that leads to the formation of the covalent bond was evaluated in silico, both thermodynamically and kinetically, using quantum mechanical-based methods. As a result, it was confirmed to be a Michael-type addition, with simultaneous abstraction of the thiol hydrogen by a water molecule, transfer of hydrogen from the water to the alpha,beta-unsaturated carbonyl group of the microcystin and addition of the sulfur to the beta-carbon of the microcystin moiety. The calculated kinetics are in agreement with previous experimental results that had indicated the reaction to occur in a second step after a fast noncovalent interaction that inhibited the enzymes per se.

2011

The phosphoprotein phosphatase family of Ser/Thr phosphatases as principal targets of naturally occurring toxins

Authors
Susana R. Pereira; Vítor M. Vasconcelos; Agostinho Antunes

Publication
Crit Rev Toxicol - Critical Reviews in Toxicology, vol.41, no.2, pp.83-110

Abstract