supported by the National Key Research and Development Program of China [grant number 2019YFA0904900];Natural Science Foundation of Jiangsu Province [grant number BK20202002].
Lactase is a member of theβ-galactosidase family of enzymes that can hydrolyze lactose into galactose and glucose.However,extracellular lactase production was still restricted to the process of cell lysis.In this stu...