PHYSICOCHEMICAL STUDIES ON STARCHES .63. MOLECULAR-SIZE AND SHAPE OF AMYLOPECTIN
PHYSICOCHEMICAL STUDIES ON STARCHES .63. MOLECULAR-SIZE AND SHAPE OF AMYLOPECTIN
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DOI：
10.1002/star.19720240802
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发表时间：
1972-01-01
期刊：
影响因子：
--
通讯作者：
JONES, IG
中科院分区：
文献类型：
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作者：
BANKS, W;GEDDES, R;JONES, IG
光散射、粘度和超离心技术已应用于许多支链淀粉样品。这些测量已经证实了大分子的非常大的尺寸，并表明这些值是真实的，而不是由于氢键导致的聚集。已将支链淀粉的流体动力学行为与密切相关的糖原的流体动力学行为进行比较。两者之间的差异已被证明是由于支链淀粉的更灵活，线圈状的性质。已经对随着pH值变化而控制支链淀粉延伸的因素进行了检查，结果表明，在适当的溶剂条件下，可以观察到“卷曲到螺旋”的转化。讨论了支链淀粉分子的构象，提出了大分子是二维实体的概念。
Light‐scattering, viscosity and ultracentrifugal techniques have been applied to a number of amylopectin samples. These measurements have confirmed the very large size of the macromolecule, and shown that such values are real, and are not due to aggregation resulting from hydrogen‐bonding. The hydrodynamic behaviour of amylopectin has been compared with that of the closely‐related glycogen. The difference between the two has been shown to be due to the much more flexible, coil‐like nature of the amylopectin. An examination has been made of the factors governing the extension of amylopectin as the pH is varied, and it is shown that under appropriate solvent conditions a “coil‐to‐helix” transformation may be observed. The conformation of the amylopectin molecule is discussed, and the concept that the macromolecule is a two‐dimensional entity is proposed.