Roles of sucrose-metabolizing enzymes in accumulation of sugars in Cabernet Sauvignon grape fruit.

In order to ascertain the relationship between accumulation of sugars and sucrose-metabolizing enzymes,the con-tent of sucrose,glucose,fructose and the activities of sucrose-metabolizin enzymes(soluble acid invertase,soluble neutral invertase,cell wall-bound acid invertase,sucrose synthase and sucrose phosphate synthase) in the fruits of Cabernet Sauvi-gnon grape were measured.The results showed that glucose and fructose were mainly accumulated in sugar accumulation of Cabernet Sauvignon grape fruits;the key enzyme which controled the grape sugar accumulation was invertase;the glucose and fructose accumulation in grape fruits were mainly mediated by invertase;the sucrose accumulation were mainly mediated by sucrose synthase;and the accumulation of sugar was controled by a variety of enzymes together.