Research Lab

Molecular Biophysics

Molecular Biophysics
29671
Research Interests

The Molecular Biophysics Lab uses a combination of biochemical and biophysical methods to study enzyme mechanisms and characterize active centers and reaction intermediates. Enzymes studied include iron storage and detoxification enzymes of the ferritin family as well as other carboxylate-bridged di-iron containing proteins and cage proteins.

Additionally, the biologic effect of ionizing radiation in macromolecules, particularly metalloenzymes, has been under study. Correlation between radiation effects and metabolites resulting from oxidative stress has been under focus.

The lab is also always interested in the continuous development of different techniques applied on such characterizations, namely biochemical techniques, molecular biology methods and various spectroscopies (UV/visible, CD, EPR and Mössbauer) in conjunction with fast kinetic techniques (stopped-flow and rapid-freeze quench).

Recently, collaborative efforts with industrial partners resulted in new applied research in Moringa oleifera plant system.

Research Highlights
Bionanocages functions and aplications

Proteins of the ferritin family can be divided into two types, the maxi-ferritins and mini-ferritins, involved in important cellular processes, that differ on the subunit composition, capable of sequester, oxidize and mineralize ferrous ions.

These two types of proteins are divided in three ferritin families: the classical ferritins, bacterioferrintins and the Dps (DNA-binding protein from starved cells). With exception of Dps that are 12-oligomers (mini-ferritins), all other ferritins are composed of 24 subunits organized into a hollow spherical protein shell that can store up to 4,500 iron atoms in the form of a ferrihydrite mineral. Dps proteins are capable of store up to 500 iron atoms per molecule. These hollow spheres can be used to incorporate different metal ions and specifically altered to produce chimeric molecules with additional functionalities with applications in medicine and biotechnology. The external interface of the ferritin family interacts with different macromolecules that are present in the surrounding environment. DNA and its interaction with proteins from the ferritin family is of special interest in the external interface of the protein. The interior cavity surface is critical to iron sequestration.

A specially interesting ability of the cavity is the possibility to, without bioengineering, synthesize different types of nanoparticles, forming specific metal cores with different applications. Another interesting application is the use of the hollow cavity as a drug delivery system.

 

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Moringa oleifera

Moringa oleifera tree (all parts, from roots to leaves, seeds and flowers) contains many nutrients such as essential vitamins and minerals, amino acids, beta-carotene, anti-oxidants, anti-inflammatory nutrients, phytochemicals and both omega-3 and omega-6 fatty acids. Well known in Asia and Africa it is used locally to cure many diseases and/or to provide nutrients. Besides, its pharmaceutical and biotechnological potential is recognized worldwide, including by the WHO. More, the development of the concepts green chemistry/green chemicals prompt for the search for new bio-sourced products that justify the current interest. Our lab, in partnership with the Laboratório de Bromatologia e Hidrologia, Departamento de Ciências Químicas, Faculdade de Farmácia da Universidade do Porto (LAQV/REQUIMTE) and the Portuguese-owned company Naturinga, established a research project to explore the development of sustainable methodologies for valorization of proteins extracted from Moringa oleifera seed-cake, a by-product of the oil (an essential oil rich in phytonutrients with great impact in overall health) extraction process, to produce bioactive protein hydrolysates to be used as an additive of supplements for sportspeople and elderly, using an array of techniques. The consortium was established taking into account the adequacy to successful accomplish the proposed aims but also a unique solid background on biochemical and biophysics, nutrition and occupational medicine, as well as to, valorization of industry by-products through recovery of added value compounds and study of its beneficial properties by in vitro studies.

 

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Representative Projects

  • “MOR2020 - Valorization of the protein fraction from Moringa oleifera”, FCT-MCTES, Total funding: €239,421, Unit funding: €116,591, Pedro Tavares (PI).

Selected Publications

Pina, AS; Carvalho, S; Dias, AMGC; Guilherme, M; Pereira, AS; Caraca, LT; Coroadinha, AS; Lowe, CR; Roque, ACA. 2016. Tryptophan tags and de novo designed complementary affinity ligands for the expression and purification of recombinant proteins. JOURNAL OF CHROMATOGRAPHY A, 1472, DOI: 10.1016/j.chroma.2016.10.017
Graca, I; Liang, JS; Guilherme, M; Tavares, P; Ferreira-Pinto, MM; Melo, AMP; Ribeiro-Barros, AI; Pereira, AS. 2016. Cloning, overexpression and functional characterization of a class III chitinase from Casuarina glauca nodules. SYMBIOSIS, 70, DOI: 10.1007/s13199-016-0403-1
Folgosa, F; Tavares, P; Pereira, AS. 2015. Iron management and production of electricity by microorganisms. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 99, DOI: 10.1007/s00253-015-6897-2
Folgosa, F; Camacho, I; Penas, D; Guilherme, M; Frois, J; Ribeiro, PA; Tavares, P; Pereira, AS. 2015. UV radiation effects on a DNA repair enzyme: conversion of a [4Fe-4S](2) cluster into a [2Fe-2S](2). RADIATION AND ENVIRONMENTAL BIOPHYSICS, 54, DOI: 10.1007/s00411-014-0569-y