Direct Observation of Enzymatic Degradation Behavior of Poly[(R)-3-hydroxybutyrate] Lamellar Single Crystals by Atomic Force Microscopy
Direct Observation of Enzymatic Degradation Behavior of Poly[(R)-3-hydroxybutyrate] Lamellar Single Crystals by Atomic Force Microscopy
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DOI：
10.1021/ma001505c
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发表时间：
2001-07
期刊：
影响因子：
5.5
通讯作者：
T. Murase;T. Iwata;Y. Doi
中科院分区：
文献类型：
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作者：
T. Murase;T. Iwata;Y. Doi
利用原子力显微镜直接观察了吸附在高度有序热解石墨表面的溶液生长的聚[（R）-3-羟基丁酸酯]（P（3 HB））单晶在粪产碱菌（Alcaligenes faecalis）T1胞外聚羟基丁酸酯（PHB）解聚酶作用下的降解行为。在降解的初始阶段，吸附和水解的酶促作用通过单晶的扭曲区域的主要降解产生较小的晶体块。随后，水解从结晶块的生成端进行，导致裂纹的形成。晶体的中部也发生了降解，产生了裂缝。几个裂纹和狭缝沿晶体长轴沿着排列，进一步的酶解将裂纹和狭缝合并成更长的裂纹。通过这些过程，酶降解将板条状层状单晶转化为板条状指状物和晶体碎片。它是由T…
The enzymatic degradation behavior of solution-grown single crystals of poly[(R)-3-hydroxybutyrate] (P(3HB)), which were adsorbed on the surface of highly ordered pyrolytic graphite, with an extracellular PHB depolymerase from Alcaligenes faecalis T1 was directly observed by atomic force microscopy. At the initial stage of degradation, enzymatic action of both adsorption and hydrolysis produced smaller crystal blocks by predominant degradation of distorted regions of a single crystal. Subsequently, the hydrolysis progressed from a generated end of the crystal block, resulting in the formation of cracks. The degradation also took place at a middle part of the crystal, yielding slits. Several cracks and slits stood in a line along the long axis of crystal, and further enzymatic hydrolysis combined the cracks and the slits into longer cracks. With these processes, the enzymatic degradation converted a lath-shaped lamellar single crystal into lathlike fingers and crystal fragments. It has been proposed from t...