Crowding interactions perturb structure and stability by destabilizing the stable core of the α‐subunit of tryptophan synthase

August 13, 2018

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

FP-6300

Keywords

Fluorescence, Protein structure, Chemical stability, Protein folding, Protein denaturation, Biochemistry