A suite of Switch i and Switch II mutant structures from the G-protein domain of FeoB

Abstract

The acquisition of ferrous iron in prokaryotes is achieved by the G-protein-coupled membrane protein FeoB. This protein possesses a large C-terminal membrane-spanning domain preceded by two soluble cytoplasmic domains that are together termed NFeoB. The first of these soluble domains is a GTPase domain (G-domain), which is then followed by an entirely -helical domain. GTP hydrolysis by the G-domain is essential for iron uptake by FeoB, and various NFeoB mutant proteins from Streptococcus thermophilus have been con-structed. These mutations investigate the role of conserved amino acids from the proteins critical Switch regions. Five crystal structures of these mutant proteins have been determ..