mutants of the uncc gene for the epsilon subunit ( 138 amino acid residues ) of escherichia coli h+-atpase were isolated : strain kf53 ( gln-72 -- -- end ) and kf148 ( sd- ) ( two base substitutions in the shine-dalgarno sequence , ggagg -- -- aaagg ) .
C0002520
amino acid
C0017797
gln