How does denaturing SDS-PAGE differ from native PAGE in analyzing GFP?

Denaturing SDS-PAGE unfolds proteins and allows them to be separated primarily based on their size. In this process, the SDS (sodium dodecyl sulfate) binds to the proteins, imparting a negative charge that masks the protein's native charge and structural characteristics. This means that, regardless of their original shapes or charges, proteins will migrate through the gel according to their linear length or mass. As a result, denaturing SDS-PAGE provides a way to analyze proteins like GFP in a highly uniform and reproducible manner, allowing for accurate comparisons of molecular weights.

In contrast, native PAGE maintains the proteins in their natural, functional state, preserving their size, shape, and charge. This method can provide insights into protein-protein interactions or the oligomeric state of the proteins but does not separate based solely on size.

Native PAGE can sometimes be quicker, but it often requires optimization of conditions and may not always yield clear results for complex mixtures. The concentration needed for native PAGE can vary greatly depending on the specifics of the protein being analyzed, but it typically does not mandate higher concentrations than SDS-PAGE.

Thus, the distinguishing feature of denaturing SDS-PAGE in the context of GFP analysis is its ability to separate proteins solely based on