ROLE OF EXTRACELLULAR PHOSPHATASES IN THE PHOSPHORUS-NUTRITION OF CLOVER
ROLE OF EXTRACELLULAR PHOSPHATASES IN THE PHOSPHORUS-NUTRITION OF CLOVER
复制标题
DOI：
10.1093/jxb/44.10.1595
复制
发表时间：
1993-10-01
影响因子：
6.9
通讯作者：
GREENWAY, H
中科院分区：
文献类型：
--
作者：
BARRETTLENNARD, EG;DRACUP, M;GREENWAY, H
本文研究了地下三叶草利用对酯作为生长磷源的能力与这些对酯在根表面的酶水解之间的关系。 Trifolium subterraneum (cv. Mt. Barker) 在无菌条件下在含有 KH2PO4 (P(i))、2',3'-环单磷酸腺苷 (cAMP) 或肌醇六磷酸 (IHP) 作为培养基中 P 来源的多孔琼脂中生长。地下三叶草使用 cAMP 和 P(i) 作为生长所需的磷源，但很少使用 IHP。这种使用 P-酯的偏好与外部可及的根磷酸酶的底物特异性的差异有关；在无菌条件下生长的缺磷三叶草的根对 cAMP 具有较高的水解活性，但对 IHP 则没有。这些结果根据外部可及磷酸酶的功能的假设进行讨论，即磷酸酶的存在是为了从细胞泄漏的有机磷化合物中重新捕获磷。
This paper examines the relationship between the ability of subterranean clover to use P-esters as sources of P for growth, and the enzymatic hydrolysis of those P-esters at the root surface. Trifolium subterraneum (cv. Mt. Barker) was grown under sterile conditions in porous agar containing either KH2PO4 (P(i)), 2',3'-cyclic adenosine monophosphate (cAMP) or inositol hexaphosphate (IHP) as the source of P in the medium. Subterranean clover used cAMP as well as P(i) as a source of P for growth, but made little use of IHP. This preference in the use of P-esters was associated with differences in the substrate specificities of the externally accessible root phosphatases; roots of P-deficient clover grown under sterile conditions had high hydrolytic activity against cAMP but not IHP. These results are discussed in terms of an hypothesis on the function of the externally accessible phosphatases, i.e. that the phosphatases are present to recapture P from organic P compounds leaked from the cells.