Department of Botany, Institute of Biology and Ecology, Faculty of Science, P. J. Šafárik University, Mánesova 23, 041 67 Košice, Slovak Republic.
J Agric Food Chem. 2010 Sep 22;58(18):10270-6. doi: 10.1021/jf101977v.
The effect of phenylalanine ammonia-lyase (PAL) inhibition by 2-aminoindane-2-phosphonic acid (AIP) in copper-exposed diploid and tetraploid chamomile (Matricaria chamomilla ) roots has been studied in a short-term experiment (24 h). Cu evoked stronger induction of PAL activity and accumulation of soluble phenols, flavonols (quercetin and kaempferol), and lignin in diploid plants, whereas AlCl3-reactive flavonoids and phenolic acids did not differ with respect to ploidy. Amounts of hydrogen peroxide and superoxide also preferentially increased in diploid. Surprisingly, PAL activity was restored in both +AIP cultivars, being inversely correlated with the accumulation of free phenylalanine. Notwithstanding this, total soluble phenols and flavonols were more depleted in Cu+AIP diploid roots. Soluble proteins decreased in response to Cu, and AIP had no effect. Among free amino acids, proline increased more visibly in Cu+AIP diploid, suggesting that this could be a protective mechanism in conditions with depleted content of phenols. Decrease in potassium content was ploidy-independent, calcium increased in all Cu variants, and Fe increased in Cu-exposed tetraploid. Shoot Cu content did not differ in Cu-exposed cultivars, but diploid roots contained more Cu. AIP decreased root Cu but increased shoot Cu amounts in diploid, whereas tetraploid plants did not exhibit similar responses. These data indicate that inhibition of root phenolic metabolism by AIP was effective enough, allowing Cu to accumulate in diploid shoots. The present findings are discussed in the context of available data about AIP effects and with respect to the role of phenols in metal uptake.
在短期实验（24 小时）中，研究了 2-氨基茚满-2-膦酸（AIP）对铜暴露的二倍体和四倍体甘菊（Matricaria chamomilla）根中天冬氨酸氨裂解酶（PAL）的抑制作用。Cu 引起二倍体植物中 PAL 活性和可溶性酚、类黄酮（槲皮素和山柰酚）和木质素的积累更强的诱导，而 AlCl3 反应性类黄酮和酚酸则与倍性无关。过氧化氢和超氧化物的量也优先在二倍体中增加。令人惊讶的是，两种+AIP 品种的 PAL 活性都得到了恢复，与游离苯丙氨酸的积累呈反比。尽管如此，Cu+AIP 二倍体根中的总可溶性酚和类黄酮含量仍然更加耗尽。可溶性蛋白质对 Cu 作出反应而减少，AIP 没有影响。在游离氨基酸中，脯氨酸在 Cu+AIP 二倍体中增加得更为明显，表明这可能是在酚类物质含量减少的情况下的一种保护机制。钾含量的减少与倍性无关，钙在所有 Cu 变异体中增加，而铁在暴露于 Cu 的四倍体中增加。暴露于 Cu 的品种的地上部 Cu 含量没有差异，但二倍体根中含有更多的 Cu。AIP 减少了根 Cu，但增加了二倍体地上部 Cu 的含量，而四倍体植物没有表现出类似的反应。这些数据表明，AIP 对根酚类代谢的抑制作用足够有效，允许 Cu 在二倍体地上部积累。本研究结果在现有关于 AIP 作用的数据和关于酚类物质在金属吸收中的作用的背景下进行了讨论。
