Accessing local structural disruption of Bid protein during thermal denaturation by absorption-mode ESR spectroscopy.

ABSTRACT: Bid is a requisite protein that connects death receptors to the initiation of mitochondrial-dependent apoptosis. Its structure was determined more than a decade ago, but its structure-function relationship remains largely unexplored. Here we investigate the thermostability of Bid protein and explore how the death-promoting function of Bid is affected by thermally-induced unfolding. First, we show by circular dichroism (CD) spectroscopy that Bid remains partially folded at high temperatures (350-368 K), and that the thermal unfolding of Bid is irreversible and accompanied with intermolecular associations that lead to protein aggregation. In 3 M GdnHCl, the onset of unfolding can, however, be conveniently observed at much lower temperatures around 320 K. We employ pulsed ESR dipolar spectros

SUBMITTER: Hung CL 

PROVIDER: S-EPMC9087001 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature