Folding intermediates of hyperthermophilic D‐glyceraldehyde‐3‐phosphate dehydrogenase from Thermotoga maritima are trapped at low temperature

FEBS Letters

Jaenicke, Rainer¹  Schultes, Verena¹ 

[1] Institut für Biophysik und Physikalische Biochemie, Universität Regensburg, D-8400 Regensburg, Germany

关键词: Cold denaturation;    Folding intermediate;    Glyceraldehyde-3-phosphate dehydrogenase;    Thermophile;    Thermotoga maritima;    GAPDH;    D-glyceraldehyde-3-phosphate dehydrogenase;    GdmCl;    guanidinium chloride;    M w;    weight average molecular weight;    s 20;    w;    sedimentation coefficient under standard conditions;   

DOI  :  10.1016/0014-5793(91)81268-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

D-Glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic eubacterium, Thermotoga maritima, is extremely thermostable showing a thermal transition beyong 105°C. At low temperature, ‘cold denaturation’ becomes detectable only in the presence of destabilizing agents. Reconstitution after preceding denaturation depends on temperature. At 0°C, no significant recovery of activity is detectable, whereas between 30 and 100°C reactivation reaches up to 85%. Shifting the temperature from low values to the range of optimum reconstitution releases the trapped intermediate in a fast reaction. Evidence from ultra-centrifugal analysis and far-UV circular dichroism proves the intermediate to be partially assembled to the tetramer, with most of its native secondary structure restored in a fast reaction. Fluorescence emission exhibits at least biphasic kinetics with the rate-limiting step(s) reflecting local adjustments of aromatic residues involved in tertiary contacts in the native state of the enzyme.

【 授权许可】

Unknown