Termites are wood pests that cause vast economic damage every year. They digest both cellulose and starch, but the enzymes for starch digestion have not been well characterized. We obtained complete amino acid sequence information on the KME1 α-amylase from Reticulitermes speratus KMT1 through analysis of total mRNA sequences. The KME1 enzyme has two α-amylase domains and is 68% identical to the α-amylase from Blattellager manica, its closest relative in the GenBank database. Some unique features of its conserved region and its distant evolutionary relationship to other insect α-amylases suggest that KME1 is a new type of α-amylase.
Among termites, lower termites need symbiotic microorganisms in the digestive tract for digestion and cellulose metabolism. In this symbiotic relationship, the decomposition of cellulose is initiated by endoglucanase in termite salivary glands and completed by β‐glycosidase of symbiotic microorganisms in the hindgut. The expression of β‐glycosidase in lower termites has been reported in recent studies. The expression of two endoglucanases and one β‐glycosidase gene related to cellulose degradation was identified in Reticulitermes speratus, a lower termite, through transcriptomic analysis. The proposed enzyme activities of three identified cellulose degradation genes were confirmed by heterologous expression in Escherichia coli. In addition to the endoglucanase expressed in the salivary gland, additional endoglucanase and β‐glycosidase genes suggest that R. speratus performs the overall cellulose digestion using its own enzymes at all stages.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.