Comparative analysis of metallothionein proteins (MTs) from different grass species

Abstract

Plant metallothioneins (MTs) are small proteins, having rich cysteine residues andappear to play key roles in metal homeostasis. In current study, MTs of 9 grass species (Brachypodium distachyon, Festuca rubra, Hordeum vulgare, Oryza sativa japonica, Oryza sativa indica, Saccharum officinarum, Sorghum bicolor, Triticum aestivum, and Zea mays) were used for in silico comparative analysis. Physicochemical analyses showed that pIvalues and GRAVY index were found to be in the range of (4.44) - (7.36) and (-0.037) - (-0.376), respectively. All MTs investigated in this study exhibited hydrophilic characterand 8 of 9 MTs had acidic nature. Also, there were no sequences containing tryptophan(Trp) residues. While the highest and lowest similar sequence identities were foundbetween S. bicolor & S. officinarum (0.928), and Z. mays & H. vulgare (0.183), respectively. Phylogenetic analysis revealed that one main group observed including two subgroups.The highest bootstrap value was observed between S. bicolor and S. officinarum (92%). Interestingly, H. vulgare appears not to be within any grass species group.