Crystal and surface structure analysis of biosynthesized aliphatic polyesters and its depolymerase

生物合成脂肪族聚酯及其解聚酶的晶体和表面结构分析

• 批准号: 11217216
• 负责人: IWATA Tadahisa
• 金额: $ 8.77万
• 依托单位: RIKEN Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11217216/
• 关键词: Biodegradable Aliphatic Polyesters; Single Crystal; Film; Crystal Structure; Surface Structure; Depolymerase; High-ordered Structure; Biodegradable Mechanism; 結晶化; 生分解性; 脂肪族ポリエステル; 透過型電子顕微鏡; 分解酵素; 酵素精製

The biodegradability of aliphatic polyesters, which are produced by biosynthesis and chemosynthesis, strongly correlated to the polymer morphology such as crystallinity, molecular orientation, chain packing state and crystal surface, in addition to the chemical structures. For elucidation of biodegradation mechanism of crystal regions by atomic level, lamellar single crystals of poly ([R]-3-hydroxybutyrate) (P(3HB)) and its copolymers, poly ([R]-3-hydroxyvalerate) (P(3HV)), poly (L-lactic acid) (PLLA). poly (β-propiolactone) (PPL), poly (δ-valerolactone) (PVL), poly (4-hydroxybutyrate) (P(4HB)), poly (ε-caprolactone) (PCL) and poly (ethylene succinate) (PES) were prepared from dilute solution by isothermal crystallization, and the crystal structures and morphologies were investigated by means of mainly transmission electron microscopy and atomic force microscopy. All single crystals were intramolecular single crystals and these crystals gave well-resolved electron diffractograms. Three … More dimensional crystal structures of PPL, P (4HB) and PVL were revealed by X-ray and electron diffractions and computer simulations.The enzymatic degradations of lamellar crystals of P(3HB) and its copolymers, PLLA, PPL, PCL and PES were carried out with extracellular PHB depolymerases or proteinase-K or lipase, and it was reveled that enzymatic degradation of lamellar crystals progressed from crystal edges and ends rather than the chain-folding surfaces of crystals without decreasing the molecular weights and lamellar thickness. These results suggest that the attack by the active site of enzyme takes place at the disordered chain-packing regions of crystals, that is, disordered lateral sides which have higher mobility of molecular chains are preferentially degraded.We succeeded to crystallize PHB depolymerase purified from Penicillium funiculosum by vapor diffusion. High-resolution data were collected under cryogenic conditions with synchrotron radiation. Native data to a resolution of 1.7 A have been collected with an R_<merge> of 6.8%. Less

生物合成和化学合成的脂肪族聚酯的生物降解性除了与化学结构有关外，还与聚合物的结晶度、分子取向、链堆积状态和晶体表面等形态密切相关。为了从原子水平上阐明结晶区的生物降解机理，制备了聚（[R]-3-羟基丁酸酯）（P（3 HB））及其共聚物、聚（[R]-3-羟基戊酸酯）（P（3 HV））、聚（L-乳酸）（PLLA）的层状单晶。采用稀溶液等温结晶法制备了聚β-丙内酯（PPL）、聚δ-戊内酯（PVL）、聚4-羟基丁酸酯（P（4 HB））、聚ε-己内酯（PCL）和聚丁二酸乙二酯（PES），并用透射电镜和原子力显微镜（AFM）研究了它们的晶体结构和形貌。所有单晶均为分子内单晶，这些晶体的电子衍射图分辨良好。三 ...更多信息 用X射线衍射、电子衍射和计算机模拟等方法研究了PPL、P（4 HB）和PVL的三维晶体结构，并用胞外的PHB解聚酶、蛋白酶K和脂肪酶对P（3 HB）及其共聚物、PLLA、PPL、PCL和PES的片晶进行了酶促降解，并且揭示了层状晶体的酶降解从晶体边缘和末端而不是链进行，折叠晶体表面而不降低分子量和片层厚度。这些结果表明，酶活性中心的攻击发生在晶体的无序链堆积区域，即分子链的无序侧边具有较高的运动性，优先被降解。高分辨率数据是在低温条件下用同步辐射收集的。已收集到分辨率为1.7 A的原始数据，R_<merge>为6.8%。少

项目成果

T. Fujiwara, M. Miyamoto, Y. Kimura, T. Iwata, Y. Doi: "Self-organization of diblock and triblock copolymers of poly(L-lactide) and poly(oxyethylene) into nano-structured bands and their network system"Macromolecules. 34(12). 4043-4050 (2001)

T. Fujiwara、M. Miyamoto、Y. Kimura、T. Iwata、Y. Doi：“聚（L-丙交酯）和聚（氧乙烯）的二嵌段和三嵌段共聚物自组织成纳米结构带及其网络系统

T. Murase, T. Iwata, Y. Doi: "Atomic force microscopy investigation of poly([R]-3-hydroxybutyrate) lamellar single crystals : Relationship between molecular weight and enzymatic degradation behaviour"Macromolecular Bioscience. 1(7). 275-281 (2001)

T. Murase、T. Iwata、Y. Doi：“聚（[R]-3-羟基丁酸酯）层状单晶的原子力显微镜研究：分子量与酶降解行为之间的关系”高分子生物科学。

Y.Kikkawa, H.Abe, T.Iwata, Y.Inoue, Y.Doi: "Crystal structure and enzymatic degradation of melt-crystallized thin films of random copolyesters of (R)-3-hydroxybutyric acid with (R)-3-hydroxyalkanoic acids"Polymer Degradation and Stability. 76. 467-478 (20

Y.Kikkawa、H.Abe、T.Iwata、Y.Inoue、Y.Doi：“(R)-3-羟基丁酸与 (R)-3 的无规共聚酯熔融结晶薄膜的晶体结构和酶促降解

T.Iwata, Y.Doi, K.Isono, Y.Yoshida: "Morphology and enzymatic degradation of solution-grown single crystals of poly (ethylene succinate)"Macromolecues. 34. 7343-7348 (2001)

T.Iwata、Y.Doi、K.Isono、Y.Yoshida：“聚（琥珀酸乙烯酯）溶液生长单晶的形态和酶促降解”大分子。

W.-K.Lee,T.Iwata,F.-Y.Su,Y.Furuhashi and Y.Doi: "Visualization on recrystallization of solution-grown poly[(R)-3-hydroxybutyrate] lamellar crystals"Macromolecular Rapid Communications. (in press).

W.-K.Lee、T.Iwata、F.-Y.Su、Y.Furuhashi 和 Y.Doi：“溶液生长聚[(R)-3-羟基丁酸酯]层状晶体重结晶的可视化”高分子快速通讯