Structural and evolutionary relationships among chitinases of flowering plants.

摘要: The analysis of nuclear-encoded chitinase sequences from various angiosperms has allowed the categorization chitinases into discrete classes. Nucleotide their catalytic domains were compared in this study to investigate evolutionary relationships between functionally distinct class III appear be more closely related fungal enzymes involved morphogenesis than other plant chitinases. ordering additional classes mainly relied on presence auxiliary domains—namely, a chitin-binding domain and carboxy-terminal extension—flanking main domain. results our phylogenetic analyses showed that I IV form well-supported monophyletic groups derived common ancestral sequence predates divergence dicots monocots. In contrast, included I* II, lacking one or both types domains, nested within sequences, indicating they have polyphyletic origin. According calculation rates, these probably arose different lineages by relatively recent deletion events. occurrence such trends cultivated plants potential involvement host–pathogen interactions are discussed.