PMID: 22132858
Yu Q, Zheng X
The crystal structure of human UDP-glucose pyrophosphorylase reveals a latch effect that influence enzymatic activity.
Biochem J. 2011 Dec 1.
UDP-glucose pyrophosphorylase (UGPase) is highly conserved among eukaryotes. UGPase reversely catalyzes the formation of UDP-glucose and is critical in carbohydrate metabolism. Previous studies have mainly focused on the UGPases from plants, fungi and parasites and indicate that the regulatory mechanisms responsible for the enzyme activity vary among different organisms. Here the crystal structure of human UGPase (hUGPase) was determined and shown to form octamers through end-to-end and side-by-side interactions. The observed latch loop in hUGPase distinctly differs from yeast UGPase (yUGPase), which could explain why hUGPase and yUGPase possess different enzymatic activities. Mutagenesis studies showed that both dissociation of octamers and mutations of the latch loop can significantly affect the UGPase activity. Moreover, this latch effect is also evolutionarily meaningful in UGPase from different species.