Purity > 90% as determined by SDS-PAGE. MW: 41.5kDa. Partial: 768-995aa. N-terminal 6xHis-SUMO-tagged. Arabidopsis thaliana (Mouse-ear cress). Plays a major role in photosynthetic sucrose synthesis by catalyzing the rate-limiting step of sucrose biosynthesis from UDP-glucose and fructose- 6-phosphate. Involved in the regulation of carbon partitioning in the leaves of plants. May regulate the synthesis of sucrose and therefore play a major role as a limiting factor in the export of photoassimilates out of the leaf. Plays a role for sucrose availability that is essential for plant growth and fiber elongation. Required for nectar secretion.