Comparative study of structural and activity changes of HIV-1 protease and its covalently linked dimer under high pressure

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F70883521%3A28110%2F17%3A63517203" target="_blank" >RIV/70883521:28110/17:63517203 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Comparative study of structural and activity changes of HIV-1 protease and its covalently linked dimer under high pressure

Original language description

High-pressure techniques are nowadays being used as a tool for studying the structure and stability of protein molecules including their oligomerization state and enzyme activity. They exploit the fact that high-pressure favours the states lowering the total volume of the system, which are, in general, the states with lower structure complexity (dissociated oligomers, unfolded proteins, etc.). HIV-1 protease is a small proteolytic enzyme active as a homodimer that is highly stable at atmospheric pressure. Application of high pressure induces dimer dissociation and, consequently, unfolding of monomers. In addition, it also causes the decrease of the proteolytic activity if this enzyme. Recently, we measured the atmospheric-pressure dissociation constant of HIV-1 protease dimer using the high-pressure tryptophan fluorescence method and showed the mutual relation between the dimer dissociation and protein unfolding [1]. In this study we compare the wild-type HIV-1 protease with its covalently linked dimer (twt) in which two monomers of HIV-1 protease are intertwined within a single polypeptide chain. The mutual comparison of these proteins shows not only higher structural stability of twt with respect to wt, but also a different influence of high pressure on the enzyme activity. This way it is possible to separate the influence of dimer dissociation to the HIV-1 protease activity from the other, dimerization independent, phenomena. The experiments show substantial contributions of both dimerization dependent and independent effects to the HIV-1 protease activity. In order to better understand the mechanisms of high-pressure influence on this protein, we carry out also molecular-dynamics simulations of this system at different pressures [2]. These simulations reveal a substantial effect of the hydrophobic active-site cavity on the volume change of the dimer dissociation as well as the influence of ions interacting with the substrate in the active site on the enzyme activity and its high-pressure modification.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

10608 - Biochemistry and molecular biology

Project

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Continuities

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů