COMPETITIVE-INHIBITION OF THE AUXIN-INDUCED ELONGATION BY ALPHA-D-OLIGOGALACTURONIDES IN PEA STEM SEGMENTS
COMPETITIVE-INHIBITION OF THE AUXIN-INDUCED ELONGATION BY ALPHA-D-OLIGOGALACTURONIDES IN PEA STEM SEGMENTS
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DOI：
10.1111/j.1399-3054.1988.tb09157.x
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发表时间：
1988-03-01
影响因子：
6.4
通讯作者：
CERVONE, F
中科院分区：
文献类型：
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作者：
BRANCA, C;DELORENZO, G;CERVONE, F
用均相黑曲霉内多聚半乳糖醛酸酶(EC 3.2.1.15)部分水解多聚酯钠制备α-D-半乳糖醛酸寡聚体(OG)。测定了经10、20、30、60、120min和24 h消化后获得的Og对IAA诱导的豌豆伸长的干扰能力。阿拉斯加)茎。聚合度近似大于8的低聚物具有最大的抑制活性，较长的OG对酶的抑制作用较小，24 h的消化产物和未水解的多聚果糖对酶的抑制作用不明显。向豌豆茎中添加OG引起IAA剂量-效应曲线的平行右移。这种转变依赖于OG的使用量，表明低聚半乳糖醛酸苷的行为是IAA的竞争性拮抗剂。OG的存在使伸长率的第二极大值消失，第一极大值减小。还测试了它们抑制IAA诱导的豌豆茎段乙烯释放的能力。与干扰IAA诱导的伸长的OG大小相同的OG获得最大的抑制作用。对生长素作用的抑制似乎是特异的，因为OG不干扰赤霉酸(GA3)或激动素的活性。结果表明，低聚半乳糖醛酸内酯虽然不能直接影响豌豆茎段的伸长，但对IAA的活性有强烈的干扰作用。
.alpha.-D-galacturonide oligomers (OG) were prepared by partial hydrolysis of sodium polypectate with an homogeneous Aspergillus niger endopolygalacturonase (EC 3.2.1.15). OG, obtained after digestion for 10, 20, 30, 60, 120 min and 24 h, were assayed for their ability to interfere with the IAA-induced elongation of pea (Pisum sativum L. cv. Alaska) stems. Maximum inhibiting activity was exhibited by oligomers with an approximate degree of polymerization higher than 8. Inhibition by longer OG was much lower, and the products of the 24 h digestion and the unhydrolysed polypectate were ineffective. The addition of OG to pea stems caused a parallel shift to the right of the IAA dose-effect curve. The shift depended on the amount of OG used, showing that oligogalacturonides behave as competitive antagonists of IAA. The presence of OG caused the disappearance of the second maximum of the elongation rate and reduced the first maximum. OG was also tested for their ability to inhibit IAA-induced ethylene evolution of pea stem segments. Maximal inhibition was obtained with OG of the same size as those that interfered with IAA-induced elongation. Inhibition of the auxin action seemed to be specific as OG did not interfere with the activity of gibberellic acid (GA3) or kinetin. It was concluded that oligogalacturonides strongly interfere with the activity of IAA, although they are by themselves incapable to influence the elongation of pea stem segments directly.