Genome-Wide Analysis Reveals Chitinases as Putative Defense-Related Proteins Against Fungi in the Genomes of Coffea arabica and Its Progenitors

Chitinases have been demonstrated to enhance plant resistance to fungi in various pathosystems. Although there is evidence of the effectiveness of these proteins in coffee–fungus interactions, no genome-wide identification or characterization of coffee chitinases has been performed. In this study, we employed phylogenetic analysis, domain architecture, gene structure analysis, and subcellular localization to identify and characterize putative genes and proteins in the genomes of Coffea arabica and its progenitors, Coffea canephora and Coffea eugenioides. A total of 113, 47, and 69 putative chitinase proteins were identified in C. arabica, C. canephora, and C. eugenioides, respectively. These chitinases were classified according to their catalytic domains, GH18 and GH19, and into Classes I, II, III, IV, and V, as determined through phylogenetic analysis based on the Arabidopsis thaliana classification. Furthermore, based on orthologous analysis, we identified ten, six, and seven putative chitinases associated with fungal defense responses in C. arabica, C. canephora, and C. eugenioides, respectively. These findings are valuable for future studies focusing on coffee chitinases, particularly on genetic programs involved in plant pathogen resistance.