Abstract

Equilibrium denaturation of dimeric mouse beta-nerve growth factor (beta-NGF) has been studied by monitoring changes in the protein's spectroscopic characteristics. Denaturation of beta-NGF in guanidine hydrochloride and urea resulted in an altered intrinsic fluorescence emission spectrum, fluorescence depolarization, and diminished negative circular dichroism. Native-like spectroscopic properties and specific biological activity are restored when denaturant is diluted from unfolded samples, demonstrating that this process is fully reversible. However, refolding of denatured beta-NGF is dependent on the three disulfide bonds present in the native protein and does not readily occur when the disulfide bonds are reduced. Graphical analysis and nonlinear least-squares fitting of beta-NGF denaturation data demonstrate that denaturation is dependent on the concentration of beta-NGF and is consistent with a two-state model involving native dimer and denatured monomer (N2 = 2D). The conformational stability of mouse beta-NGF calculated according to this model is 19.3 +/- 1.1 kcal/mol in 100 mM sodium phosphate at pH 7. Increasing the hydrogen ion concentration resulted in a 25% decrease in beta-NGF stability at pH 4 relative to pH 7. Study holds ProTherm entries: 10369, 10370, 10371, 10372, 10373, 10374 Extra Details: beta-nerve growth factor; denaturation; fluorescence; protein structure

Submission Details

ID: SyGQaG7Q4

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:40 p.m.

Version: 1

Publication Details

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