A distinct molecular signature on anhydrobiotic cyanobacterial metallothioneins

Anhydrobiosis refers to a state of suspended animation in which some organisms enter when exposed extreme desiccation, ensuring them an outstanding tolerance several physical stresses due molecular and cellular adaptations. Metallothioneins (MTs) are short cysteine-rich metal-chelating proteins that work as protection element metal ion-rich conditions. Here we aimed investigate possible signatures primary tertiary structures anhydrobiotic cyanobacterial MTs. Anhydrobiotic non-anhydrobiotic MT amino acid sequences were retrieved from NCBI database aligned Clustal Omega server. Additionally, the compositions these determined by GeneRunner. Further, carried out homology-modeling via SWISS-MODEL, structural superposition UCSF Chimera 1.4 Matchmaker tool ligand-binding site prediction COFACTOR. In silico analyses revealed specific divergences positions between groups, evidencing positive negative selections, however without affecting final protein structures. Some changes on polypeptide sequence potentially enhance stabilization during whereas others possibly act additional metal-ion coordinating residues. Analyses adaptations MTs help shed light their functions biological roles, well may have applications development desiccation- metal-tolerant organisms.