基于多肽质谱检测的丝绸细菌劣化机理研究  

Study on bacterial degradation of silk based on detection of peptide by mass spectrometry

作　　者：泮林丹 陈浩[1] 杨海亮 王秉[1] PAN Lindan;CHEN Hao;YANG Hailiang;WANG Bing(School of Materials Science&Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China;China National Silk Museum,Hangzhou 310002,China)

机构地区：[1]浙江理工大学材料科学与工程学院,杭州310018 [2]中国丝绸博物馆,杭州310002

出　　处：《浙江理工大学学报（自然科学版）》2023年第4期493-499,共7页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：国家重点研发计划(2019YFC1520300);国家自然科学基金项目(52273096);浙江省文物保护科技项目(2020012)。

摘　　要：为研究丝绸文物的微生物劣化降解机理,选取铜绿假单胞菌和嗜麦芽窄食单胞菌对丝织品进行模拟劣化,并通过扫描电子显微镜和傅里叶红外光谱分别观察了丝绸劣化后微观形貌和二级结构的变化,同时对丝绸的劣化降解液进行了基于蚕丝蛋白数据库匹配的多肽质谱检测,以揭示2种细菌对丝绸蛋白的降解机理。结果显示:丝绸纤维表面经劣化后发生了纵向剥离;2种细菌对丝绸纤维无定形区的降解程度比结晶域高;降解的丝绸蛋白绝大多数为重链和轻链以外的其他蛋白,且嗜麦芽窄食单胞菌对丝蛋白的整体破坏能力强于铜绿假单胞菌;将组成重链蛋白的氨基酸残基分成了Header、Linker、(GX)n和C-ter 4个基序,对其进行降解分析,结果表明Header和Linker基序处的氨基酸残基相较于(GX)n和C-ter基序更易断裂,细菌对Linker基序的破坏能力差异是影响重链蛋白降解效果的重要因素;丝蛋白链中无定形区的破坏会暴露丝蛋白大分子链上的微晶体嵌段,进一步加剧丝肽溶出,导致丝织品逐渐降解。该研究为探索古代丝绸的微生物劣化机理研究提供了一种新思路。In order to study the microbial degradation mechanism of silk cultural relics,Pseudomonas aeruginosa and Stenotrophomonas maltophilia were selected to simulate the degradation of silk fabrics,and the changes in the microscopic morphology and secondary structure of silk after degradation were observed by scanning electron microscopy and Fourier infrared spectroscopy.Meanwhile,the degradation solution of silk was detected by polypeptide mass spectrometry based on the matching of silk protein database to reveal the degradation mechanism of silk protein by two bacteria.The results showed that the surface of silk fibers is axially peeled after deterioration.The degradation degree of the two bacteria in the amor phous region of silk fibers was higher than that in the crystalline region.Most of the degraded proteins are other proteins except heavy chain and light chain,and the overall destructive ability of Stenotrophomonas maltophilia to silk filaments is stronger than that of Pseudomonas aeruginosa.The amino acid residues of the heavy chain protein were divided into four moieties,namely,Header,Linker,(GX)n and C-ter,which were further analyzed for the degradation of heavy chain protein.The results showed that the amino acid residues in the Header and Linker moieties are more likely to be broken than the(GX)n and C-ter motifs,and the difference in the destruction ability of Linker moieties is a significant factor that affect the degradation effect of heavy chain protein.The destruction of amorphous regions can lead to the exposure of micro-crystal blocks on the molecular chains of silk proteins and further accelerate the dissolution of silk peptides,resulting in gradual degradation o f silk fabric.This research provides a new insight into the mechanism of microbial degradation of ancient silk.

关 键 词：肽段 质谱分析 丝织品 嗜麦芽窄食单胞菌 铜绿假单胞菌 重链蛋白 

分 类 号：TS141[轻工技术与工程—纺织材料与纺织品设计]