Kinetic and thermodynamic characterization of a novel low-temperature-active xylanase from Arthrobacter sp. GN16 isolated from the feces of Grus nigricollis.

We previously presented the cloning, heterologous expression, and characterization of a novel multidomain endoxylanase from Arthrobacter sp. GN16 isolated from the feces of Grus nigricollis. Molecular and biochemical characterization studies indicate that the glycoside hydrolase (GH) family 10 domain at the N-terminus of the multidomain xylanase (rXynAGN16L) is a low-temperature-active endoxylanase. Many low-temperature-active enzymes contain regions of high local flexibility related to their kinetic and thermodynamic properties compared with mesophilic and thermophilic enzymes. However, the thermodynamic property of low-temperature-active xylanases, including rXynAGN16L, has rarely been reported. In this study, the kinetic and thermodynamic properties of rXynAGN16L were determined using different substrates and temperature conditions to completely characterize its activity properties. The kinetic property of rXynAGN16L is similar to some low-temperature-active GH 10 endoxylanases. Moreover, the thermodynamic property indicates that rXynAGN16L is typically characterized as a low-temperature-active enzyme.