Transglutaminases (TGases) are a class of enzyme widely spread in nature, and observed in plants, microorganisms, vertebrates and invertebrates. This enzyme catalyzes post-translational protein modification, by acyl transfer reactions, deamidation and crosslinking (polymerisation). There is a large interest for TGases functions, in particular for human TGases and their involvement in physiopathological processes. In bacteria, TGases appear largely present, although the function of this enzyme is still unknown. Microbial TGases (MTG, or MTGase) are of extreme interest, in particular MTGase from Streptomyces mobaraensis, used in biopolymers industry, in cosmetics production, in wool textiles, and in the food processing. We present the results of bioinformatics analysis on MTGases sequences, based on database searching, sequence comparisons and alignments, phylogenetic tree constructions, with the aim of improving the knowledge of MTGases, in the perspective of investigating by protein modelling and simulations techniques the functional features.