title: Enzymatic degradation of Antheraea pernyi silk fibroin 3D scaffolds and fibers.
abstract: In this study, the in vitro enzymatic degradation behavior of the regenerated Antheraea pernyi silk fibroin (Ap-SF) three-dimensional (3D) scaffolds and the natural Ap-SF fibers exposed to enzyme solutions of α-chymotrypsin, collagenase IA and protease XIV were investigated. The results indicated that all three proteases could degrade the Ap-SF 3D scaffolds, and the degradation ability was in the order protease XIV>collagenase IA>α-chymotrypsin. The regenerated Ap-SF 3D scaffold could be degraded completely in 18 days when exposed to 1.0 U/ml protease XIV at 37°C, whereas under the same condition, the natural Ap-SF fiber only lost 5.6% of its weight, revealing its long-term degradation characteristics. There were abundant peptides and some free amino acids in the Ap-SF degradation products, but no free alanine. We suggested that the polyalanine block in the regenerated Ap-SF 3D scaffolds had strong resistance to enzyme attack. The proteolytic attack occurred in the non-polyalanine block of Ap-SF. The degradation rate of Ap-SF materials depended on the molecular conformation of Ap-SF, which could be controlled in the manufacturing process.
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, No. 199 Ren'ai Road, Industrial Park, Suzhou 215123, China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Zhao
authors.forename: Xiufang
authors.initials: X
authors.lastname: Wu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Shuqin
authors.initials: S
authors.lastname: Yan
authors.forename: Mingzhong
authors.initials: M
authors.lastname: Li
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002850:Chromatography, Gel; D002918:Chymotrypsin / Q000378:metabolism; D017364:Collagenases / Q000378:metabolism; D004798:Enzymes / Q000378:metabolism*; D005349:Fibroins / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D009036:Moths / Q000737:chemistry*; D011402:Pronase / Q000378:metabolism; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000596:Amino Acids; D004798:Enzymes; D005349:Fibroins; D002918:Chymotrypsin; C117608:alpha-chymotrypsin; D017364:Collagenases; D011402:Pronase; C417249:collagenase 1