摘要
以不同成熟度的草莓果实为试材,研究了草莓果实成熟过程中Ca2+-ATPase活性变化规律、最适pH值、动力学参数Km值和Vmax值。研究结果表明,草莓果实从开始成熟时(绿熟期)Ca2+-ATPase活性不断升高,果实完全成熟时(粉红期)达到最大值,随着成熟后的不断衰老,其活性逐渐降低;该酶的最适pH值为7.0;不同成熟阶段果实Ca2+-ATPase反应所需的Ca2+浓度有所不同,EGTA对各成熟阶段草莓果实的Ca2+-ATPase活性的抑制作用存在明显的差异。经对Ca2+-ATPase的动力学分析表明,不同成熟度果实Ca2+-ATPase的Km值和Vmax值不同,从果实开始成熟Km值逐渐降低,衰老时又逐渐上升,变化趋势与酶活性变化趋势相反;Vmax值变化趋势与酶活性变化趋势相同。
The activity,optimum pH,Km and Vmax of Ca 2+ -ATPase were studied in the different ripening stage of 'Chunxing' strawberry(Fragaria ananassa Duch.).The results indicated that the activity of Ca 2+ -ATPase increased at the beginning of fruit ripening,and reached the peak in pink stage,and then dropped rapidly after pink stage.The optimum pH of Ca 2+ -AT-Pase was7.0.Both the optimum reaction concentration of Ca 2+ and the inhibition rate of EGTA were different depending on the ripening stage.The kinetic of Ca 2+ -ATPase were analyzed in this paper.The results displayed that the change of Km was opposite to that of activity and the change of Vmax was similar to that of activity.
出处
《果树学报》
CAS
CSCD
北大核心
2003年第2期99-102,共4页
Journal of Fruit Science
