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

Area of Science:

• Biochemistry
• Structural Biology
• Biophysics

Background:

• Proteins require stabilization against environmental stresses like dehydration for biotechnological applications.
• Late Embryogenesis Abundant (LEA) proteins are known for their protective roles in desiccated organisms.
• Red fluorescent protein mKate2's utility can be limited by its sensitivity to drying.

Purpose of the Study:

• To evaluate the protective efficacy of a short model peptide from Group 3 LEA (G3LEA) proteins on mKate2 fluorescence under desiccation.
• To compare the protective ability of the G3LEA model peptide against native G3LEA protein, trehalose, and Bovine Serum Albumin (BSA).

Main Methods:

• Repeated dehydration-rehydration cycles were applied to mKate2 alone and in combination with various additives.
• Fluorescence intensity measurements were used to quantify the preservation of mKate2 activity.
• Structural integrity of the mKate2 active site was inferred from fluorescence retention.

Main Results:

• mKate2 fluorescence intensity significantly decreased after repeated dehydration-rehydration treatments when used alone.
• The presence of the G3LEA model peptide maintained mKate2 peak fluorescence intensity almost perfectly during desiccation stress.
• The G3LEA model peptide demonstrated superior protective capabilities compared to native G3LEA protein, trehalose, and BSA.

Conclusions:

• Short model peptides derived from G3LEA proteins can effectively protect the structural integrity and function of fluorescent proteins under severe desiccation.
• These LEA-derived peptides represent a promising strategy for stabilizing proteins in a dry state, enhancing their utility in various applications.
• The G3LEA model peptide offers a more effective solution for protein stabilization during dehydration than conventional protectants.