Cysteine, silver-staining

An increase in sensitivity is realized by silver-staining, where residues containing sulfur (cysteine, methionine) or basic side chains (arginine, lysine, histidine) reduce Ag+, leading to brown or black colored bands. Here, down to 0.1 ng of protein can be detected. 

CyDye DIGE Fluor saturation dye Cy3, Cy5 100% of cystein residues One himdred times higher than silver staining... 

Figure 4 MARTXvc is processed in a CPD-dependent manner, (a) Silver stain of culture supernatants harvested from V. chderae strains harboring either an intact tixA gene (wt), a null mutation in rtxA ArtxA) or a point mutation in the CPD catalytic cysteine (C3581A).

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