Citrus Research and Education Centre, University of Florida, IFAS, Lake Alfred, Florida 33850.
Plant Physiol. 1991 Aug;96(4):1014-7. doi: 10.1104/pp.96.4.1014.
Tonoplast vesicles and vacuoles isolated from red beet (Beta vulgaris L.) hypocotyl accumulated externally supplied [(14)C]sucrose but not [(14)C]sucrose phosphate despite the occurrence of sucrose phosphate phosphohydrolytic activity in the vacuole. The activities of sucrose synthase and sucrose phosphate synthase in whole cell extracts were 960 and 30 nanomoles per milligram protein per minute, respectively; whereas, no sucrose synthesizing activity was measured in tonoplast preparations. The results obtained in this investigation are incompatible with the involvement of sucrose phosphate synthase in the process of sucrose synthesis and accumulation in the storage cells of red beet.
从红甜菜(Beta vulgaris L.)下胚轴分离得到的液泡膜囊泡和液泡尽管存在蔗糖磷酸磷酸水解活性,但仍能积累外源提供的 [(14)C]蔗糖,而不能积累 [(14)C]蔗糖磷酸。在整个细胞提取物中,蔗糖合酶和蔗糖磷酸合酶的活性分别为每分钟每毫克蛋白 960 和 30 毫摩尔;而在液泡膜制剂中则未测量到蔗糖合成活性。本研究的结果与蔗糖磷酸合酶参与红甜菜储存细胞中蔗糖合成和积累的过程不一致。