A LEA model peptide protects the function of a red fluorescent protein in the dry state

We tested whether a short model peptide derived from a group 3 late embryogenesis abundant (G3LEA) protein is able to maintain the fluorescence activity of a red fluorescent protein, mKate2, in the dry state. The fluorescence intensity of mKate2 alone decreased gradually through repeated dehydration-rehydration treatments. However, in the presence of the LEA model peptide, the peak intensity was maintained almost perfectly during such stress treatments, which implies that the three dimensional structure of the active site of mKate2 was protected even under severe desiccation conditions. For comparison, similar experiments were performed with other additives such as a native G3LEA protein, trehalose and BSA, all of whose protective abilities were lower than that of the LEA model peptide.
Highlights • We prepared a 22-mer model peptide of a group-3 LEA protein. • The fluorescent peak of a red fluorescent protein was almost lost on drying. • The model peptide suppressed such desiccation-induced damage. • This indicates that the 3D structure of the fluorophore was protected. • The peptide exhibited the highest protective effect among the reagents tested.