N-terminal domain unfolds first in the sequential unfolding of papain.
Temperature and Guanidine hydrochloride induced unfolding transitions of papain at pH 2.0 are biphasic implying independent and sequential unfolding of its two domains. To determine the order of unfolding, the active site located in the interface of the domains was labeled with an environment specific fluorescent probe (1,8-IAEDANS). Unfolding of this complex relative to the free protein followed by intrinsic and extrinsic fluorescence measurements suggests that the N domain unfolds initially in the sequential unfolding of domains.
Sharma
Yagya Valkya
YV
Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India.
Jagannadham
M V
MV
D001665:Binding Sites; D019791:Guanidine / Q000737:chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D009282:Naphthalenesulfonates / Q000737:chemistry; D010206:Papain / Q000737:chemistry*; D011489:Protein Denaturation; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D013050:Spectrometry, Fluorescence / Q000379:methods
D009282:Naphthalenesulfonates; C006422:1,8-I-AEDANS; D010206:Papain; D019791:Guanidine