Global regulators are proteins that can repress oractivate the expression of large numbers of genes inan organism. A recent report describes structural studieson the anti-repressor AbbA from thebacterium Bacillussubtilis [Tucker etaL, J. Mol. Biol. (2014)]. This protein hasthe ability to bind to a second protein, a globalrepressor named AbrB.
These researchers first characterized their recombinantversion of AbbA, a 65-residue protein preparedin E.colicells.
(Qa).During the isolation andpurification of AbbA, samples were monitored using a combinationof SDS-PAGE gels, Bradford and BCAassays. Identify the general chemical propertiesutilized for protein measurements by 1. Bradfordand 2. BCA assays.In each case, comment on theeffectiveness of the particular assay for monitoringprotein concentration.
(Qb).What specificinformation is obtained for a protein sample from an SDS-PAGE gelthat cannot be obtained from the Bradford or BCAprocedures?
