Posttranslational modifications to proteins do not correlate with changes in RBC oxygen-handling function. (A) Proteomic analysis of RBC lysates (under S = standard or H = hypoxia storage, or in Rej = rejuvenated and Pre = its control). Heatmap shows signal filtered for proteins in the oxidized state. (B) Proteins for which oxidation was significantly affected by hypoxic storage. Top row shows total protein signal (unfiltered), and bottom row shows peptides gated for oxidized state. Note that these do not relate directly to oxygen transport. (C) Analysis of proteins directly involved in oxygen transport or shown previously to undergo oxidative damage during standard storage. Hypoxic storage had no effect on this posttranslational modification.