The size of the cellulose microfibril.
The size of the cellulose microfibril.
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DOI：
10.1083/jcb.17.1.105
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发表时间：
1963-04
期刊：
影响因子：
--
通讯作者：
COLVIN JR
中科院分区：
文献类型：
--
作者：
COLVIN JR
最近，通过模型遮蔽实验数据的外推，纤维素微纤维的横向宽度估计为30 A，而不是大约150至200 A。这种差异归因于阴影期间沉积的一层金属。然而，与阴影方向平行和垂直的相同微原纤维的直接照片，微原纤维的无阴影部分与相同微原纤维的阴影部分的比较，染银的无阴影微原纤维，以及无阴影、未染色的微原纤维片段的直接照片，没有证据表明在正常条件下阴影材料中有这种厚度的金属层。此外，从阴性染色实验中获得的约35 A宽的微纤维链的证据受到长丝形式和纤维素对磷钨酸的可变正吸附的偏倚。因此，天然纤维素微原纤维的真正横向宽度约为目前公认值的五分之一的结论尚未得到明确的直接实验证据的证明。
Recently the lateral width of the cellulose microfibril has been estimated as 30 A rather than about 150 to 200 A, by extrapolation of data from model shadowing experiments. The difference was attributed to a layer of metal deposited during shadowing. However, direct photographs of the same microfibrils parallel and perpendicular to the direction of shadowing, of unshadowed portions of microfibrils compared with shadowed portions of the same microfibrils, of silver-stained unshadowed microfibrils, and of unshadowed, unstained segments of microfibrils give no evidence of a layer of metal of this thickness in material shadowed under normal conditions. Furthermore, the evidence for microfibril strands of about 35 A in width from negative-staining experiments is subject to a bias from the form of the filaments and from variable positive adsorption of phosphotungstic acid by cellulose. Consequently, the conclusion that the true lateral width of native cellulose microfibrils is about one-fifth of the presently accepted value is not yet justified by unequivocal direct experimental evidence.