TY - JOUR
T1 - Refolding of urea-induced denaturation of model proteins by trimethylamine N-oxide
AU - Attri, Pankaj
AU - Venkatesu, Pannuru
N1 - Funding Information:
We are gratefully acknowledged the Council of Scientific Industrial Research (CSIR), New Delhi, grant No. 01(2343)/09/EMR-II , Department of Science and Technology (DST), New Delhi, India (Grant No. SR/SI/PC-54/2008 ) and University Grants Commission (UGC), New Delhi, for financial support.
PY - 2011/11/10
Y1 - 2011/11/10
N2 - The biomolecules are known to be stabilized by osmolytes, trimethylamine-N-oxide (TMAO) while urea, destabilizes the protein structures. The deleterious effect of urea on proteins has been counteracted by TMAO is well understood; nonetheless, refolding of urea-induced conformational changes of proteins by TMAO is still an active subject. To understand the refolding ability of TMAO from urea-induced denaturation of biomolecules, we have performed transfer free energy (ΔG′tr) and the hydrodynamic diameter (dH) of cyclic dipeptides (CDs) such as, cyclo(Gly-Gly), and cyclo(Leu-Ala) through solubilities and dynamic light scattering (DLS) measurements, respectively. We observed positive and negative values of ΔG′tr for CDs from water to TMAO and urea, respectively. Our results reveal that TMAO is a refolding additive for urea deleterious actions on CDs at 1:1 and 1:2 molar ratios of TMAO and urea. However, TMAO (1 M) fails to refolding CDs structure from the urea (3-5 M)-induced conformational changes on CDs.
AB - The biomolecules are known to be stabilized by osmolytes, trimethylamine-N-oxide (TMAO) while urea, destabilizes the protein structures. The deleterious effect of urea on proteins has been counteracted by TMAO is well understood; nonetheless, refolding of urea-induced conformational changes of proteins by TMAO is still an active subject. To understand the refolding ability of TMAO from urea-induced denaturation of biomolecules, we have performed transfer free energy (ΔG′tr) and the hydrodynamic diameter (dH) of cyclic dipeptides (CDs) such as, cyclo(Gly-Gly), and cyclo(Leu-Ala) through solubilities and dynamic light scattering (DLS) measurements, respectively. We observed positive and negative values of ΔG′tr for CDs from water to TMAO and urea, respectively. Our results reveal that TMAO is a refolding additive for urea deleterious actions on CDs at 1:1 and 1:2 molar ratios of TMAO and urea. However, TMAO (1 M) fails to refolding CDs structure from the urea (3-5 M)-induced conformational changes on CDs.
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U2 - 10.1016/j.tca.2011.09.006
DO - 10.1016/j.tca.2011.09.006
M3 - Article
AN - SCOPUS:80455176984
SN - 0040-6031
VL - 526
SP - 143
EP - 150
JO - Thermochimica Acta
JF - Thermochimica Acta
IS - 1-2
ER -