Table 4.

Cysteine residues with unresolved GSH-like electron density and effect of their substitution by alanine or serine on Na,K-ATPase activity.

PDB ID/Cys position	3WGU	3WGV	3KDP	4HYT	3B8E	Na,K-ATPase activity according to [24], mutant/wild type, %
204	Density	Density	Small density	Small density	Small density	49.2
242						—a
367	Density	Fragmented density	Distant density	nd	nd	23.4
698						22.9
452	Density	Fragmented density	Density	Fragmented density	Density	25.3b
456
599	Density	Fragmented density	Density	Fragmented Density	Density	43.5

Abbreviations and all other details are given in the legend of Table 2.

^aCells with Cys 242 Ala or Cys 242 Ser mutant of Na,K-ATPase did not survive under ouabain selective pressure.

^bActivity of Cys 452, Cys 456, and Cys 457 Ser mutant of Na,K-ATPase.