Maintenance and thermal stabilization of NADH dehydrogenase-2 conformation upon elimination of its C-terminal region.

Autor: Villegas JM; Instituto Superior de Investigaciones Biológicas (Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de Tucumán), and Instituto de Química Biológica Dr Bernabé Bloj (Universidad Nacional de Tucumán), Chacabuco 461, San Miguel de Tucumán T4000ILI, Argentina., Torres-Bugeau CM, Chehín R, Burgos MI, Fidelio GD, Rintoul MR, Rapisarda VA
Jazyk: angličtina
Zdroj: Biochimie [Biochimie] 2013 Feb; Vol. 95 (2), pp. 382-7. Date of Electronic Publication: 2012 Oct 23.
DOI: 10.1016/j.biochi.2012.10.010
Abstrakt: Development of an artificial enzyme with activity and structure comparable to that of natural enzymes is an important goal in biological chemistry. Respiratory NADH dehydrogenase-2 (NDH-2) of Escherichia coli is a peripheral membrane-bound flavoprotein, belonging to a group of enzymes with scarce structural information. By eliminating the C-terminal region of NDH-2, a water soluble version with significant enzymatic activity was previously obtained. Here, NDH-2 structural features were established, in comparison to those of the truncated version. Far-UV circular dichroism, Fourier transform infrared spectroscopy and limited proteolysis analysis showed that the overall structure of both proteins was similar at 30 °C. Experimental data agree with the predicted NDH-2 structure (PDB: 1OZK). The absence of C-terminal region stabilized in ∼5-10 °C the truncated protein conformation. However, truncation impaired enzymatic activity at low temperatures, probably due to the weak interaction of the mutant protein with FAD cofactor.
(Copyright © 2012 Elsevier Masson SAS. All rights reserved.)
Databáze: MEDLINE
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