Fachbereich Biologie, Universität, Pfaffenbergstraße, D-6750, Kaiserslautern, Federal Republic of Germany.
Planta. 1974 Sep;119(3):233-45. doi: 10.1007/BF00429047.
Elongating upper and non-elongating lower segments of mung bean hypocotyls (Phaseolus aureus Roxb.) were compared in their ability to incorporate labelled polymers into their cell walls when fed with [(14)C]proline. The non-growing segments incorporated more amino acids into the walls and showed a higher degree of hydroxylation of the proline residues. The proportion of the [(14)C]polymer solubilized by chaotropic or complexing solutes was lower in the non-growing segments, possibly because of enhanced formation of covalent crosslinks between the glycoprotein and other cell wall constituents.The [(14)C]polymer was extracted from the wall by alkali at room temperature after removal of most of the hemicellulose by alkali at 0°, regardless of whether or not the pectic substances were first removed. The alkali does not extract any of the pectic polyuronide. Similar results were obtained with 6 M guanidine thiocyanate, which solubilizes appreciable amounts of the glycoprotein at room temperature and neutral pH without removing pectic substances.The results are considered to indicate a cell wall structure in mung bean hypocotyl tissue in which at least part of the pectin and some of the glycoprotein are not linked covalently together or to other cell wall constituents.
在喂食 [(14)C]脯氨酸时，比较了绿豆下胚轴伸长的上节段和非伸长的下节段将标记聚合物掺入细胞壁的能力。非生长节段将更多的氨基酸掺入细胞壁中，并显示出脯氨酸残基更高程度的羟化。在非生长节段中，用离液或络合溶质溶解的 [(14)C]聚合物的比例较低，这可能是由于糖蛋白与其他细胞壁成分之间形成了共价交联的增强。在用碱在 0°C 去除大部分半纤维素后，用碱在室温下从细胞壁中提取 [(14)C]聚合物，无论是否首先去除果胶物质。碱不提取任何果胶聚半乳糖醛酸。用 6 M 硫氰酸胍也得到了类似的结果，该胍在室温下和中性 pH 值下可溶解相当量的糖蛋白，而不会去除果胶物质。这些结果表明绿豆下胚轴组织中的细胞壁结构，其中至少部分果胶和一些糖蛋白没有通过共价键连接在一起或与其他细胞壁成分连接。
