The kinetics of thermal stress induced denaturation of Aquaporin 0.

Aquaporin 0 (AQP0) is an integral membrane protein that facilitates water transport and cellular adhesion in the lens. Its dysfunction has been associated with cataractogenesis. Our earlier studies showed AQP0 undergoes aggregation when subjected to thermal stress and this aggregation seems to have been facilitated by mechanical agitation brought about by gentle stirring.

Design of a simple cryogenic system for ultraviolet-visible absorption spectroscopy with a back-reflectance fiber optic probe.

We report a convenient and inexpensive technique for the rapid acquisition of absorption spectra from small samples at cryogenic temperatures using a home built cryostat with novel collection optics. A cylindrical copper block was constructed with a coaxial bore to hold a 4.00 mm diameter electron paramagnetic resonance (EPR) tube and mounted on a copper feed in thermal contact with liquid nitrogen.

Thermal stress induced aggregation of aquaporin 0 (AQP0) and protection by α-crystallin via its chaperone function.

Aquaporin 0 (AQP0) formerly known as membrane intrinsic protein (MIP), is expressed exclusively in the lens during terminal differentiation of fiber cells. AQP0 plays an important role not only in the regulation of water content but also in cell-to-cell adhesion of the lens fiber cells. We have investigated the thermal stress-induced structural alterations of detergent (octyl glucoside)-solubilized calf lens AQP0.

A pH dependence study on the unfolding and refolding of apoazurin: comparison with Zn(II) azurin.

Azurin, a small blue copper protein from the bacterial species Pseudomonas aeruginosa, is mostly a beta-sheet protein arranged into a single domain. Previous folding studies have shown that the equilibrium denaturation of the holoprotein follows a two-state process; however, upon removal of the copper, the denaturation had been reported to follow a three-state process. The two unfolding transitions measured for apoazurin had been thought to arise from two different folding domains.