Fig. 4.
Charge changes at BamA E470 increase the activity of BamA. (A) Residues at BamAE470 affect the conformational stability of BamA. A BamA-depletion strain carrying plasmid-encoded bamAE470 alleles was grown to midlog in the absence of arabinose. Boiled (denatured) and folded samples were analyzed by gel electrophoresis. (B) BamAE373K/E470K is viable in haploid. The BamA depletion strain carrying the indicated plasmids was serially diluted onto LB media alone or LB containing arabinose or fucose to monitor dependence on the chromosomally encoded bamA. (C) Suppression of bamAE373K correlates with charge of bamAE470 allele. The indicated strains were analyzed for haploid viability as described in B.