Title
Crowding interactions perturb structure and stability by destabilizing the stable core of the α-subunit of tryptophan synthase
Author
Rajashekar Varma Kadumuri, Jagadeesh Gullipalli, SriVidya Subramanian, Garima Jaipuria, Hanudatta S. Atreya, Ramakrishna Vadrevu
Year
2016
Journal
FEBS Letters
Abstract
The consequences of crowding derived from relatively small and intrinsically disordered proteins are not clear yet. We report the effect of ficoll-70 on the structure and stability of native and partially folded states of the 29 kDa alpha subunit of tryptophan synthase (αTS). Overall, combining the changes in the circular dichroism and fluorescence spectra, in conjunction with the gradual loss of cooperativity under urea denaturation in the presence of increasing amounts of ficoll, it may be concluded that the crowding agent perturbs not only the native state but also the partially folded state of αTS. Importantly, NMR data indicate that ficoll interacts with the residues that constitute the stable core of the protein thus shedding light on the origin of the observed perturbation.
Instrument
J-1500, 815
Keywords
Circular dichroism, Secondary structure, Tertiary structure, Ligand binding, Protein denaturation, Biochemistry