Maiti I B, Loewus F A
Department of Agricultural Chemistry, Washington State University, Pullman, Washington 99164.
Plant Physiol. 1978 Aug;62(2):280-3. doi: 10.1104/pp.62.2.280.
Addition of myo-inositol to pentaerythritol-based germination media repressed the conversion of d-[1-(14)C]glucose to labeled uronosyl and pentosyl units of tube wall pectic substance in lily pollen (Lilium longiflorum Thunb.). Conversion of d-[1-(14)C]glucose to labeled glucosyl, galactosyl, and rhamnosyl units was unaffected. The reverse experiment, addition of d-glucose to pentaerythritol-based media, failed to affect the conversion of myo-[2-(3)H]inositol to uronosyl and pentosyl units although the flow of label into products of myo-inositol-linked glucogenesis was blocked. Results of these experiments are discussed in terms of a functional myo-inositol oxidation pathway.d-[1-(14)C]Glucose-labeled pollen tubes contain a labeled, 70% ethyl alcohol-soluble, acidic compound whose formation is blocked by the myo-inositol antagonist, 2-O,C-methylene-myo-inositol (Chen et al. 1977 Plant Physiol. 59: 658). This compound has been identified as l-malic acid.
在基于季戊四醇的萌发培养基中添加肌醇,可抑制百合花粉(Lilium longiflorum Thunb.)中d-[1-(14)C]葡萄糖向管壁果胶物质的标记糖醛酰基和戊糖基单元的转化。d-[1-(14)C]葡萄糖向标记的葡萄糖基、半乳糖基和鼠李糖基单元的转化不受影响。反向实验,即在基于季戊四醇的培养基中添加d-葡萄糖,尽管标记物向肌醇连接的糖异生产物的流动受阻,但未能影响肌醇-[2-(3)H]向糖醛酰基和戊糖基单元的转化。根据功能性肌醇氧化途径对这些实验结果进行了讨论(d-[1-(14)C]葡萄糖标记的花粉管含有一种标记的、70%乙醇可溶的酸性化合物,其形成被肌醇拮抗剂2-O,C-亚甲基-肌醇阻断(Chen等人,1977年,《植物生理学》59:658)。该化合物已被鉴定为L-苹果酸。