Cysteine/metabolism; Diatoms/enzymology; Phosphoglycerate Kinase/metabolism; Plastids/enzymology; Amino Acid Sequence; Cloning, Molecular; Diamide/pharmacology; Diatoms/genetics; Diatoms/physiology; Disulfides/metabolism; Dithiothreitol/pharmacology; Electrophoresis, Polyacrylamide Gel; Enzyme Activation; Enzyme Assays; Enzyme Inhibitors/pharmacology; Escherichia coli/genetics; Escherichia coli/metabolism; Glutathione/pharmacology; Hydrogen Peroxide/pharmacology; Models, Molecular; Molecular Sequence Data; Mutagenesis, Site-Directed; Nitroprusside/pharmacology; Oxidation-Reduction; Phosphoglycerate Kinase/genetics; Plasmids/genetics; Plasmids/metabolism; Plastids/genetics; Recombinant Proteins/genetics; Recombinant Proteins/metabolism; Sequence Alignment; Sulfenic Acids/metabolism; Thioredoxins/pharmacology