【作者】 李琳；

【导师】 于长青；

【作者基本信息】 黑龙江八一农垦大学 ， 食品科学， 2015， 硕士

【摘要】 众所周知胆固醇水平过高会对人体健康产生危害，它是诱发心血管疾病的主要因素，目前心血管疾病已经成为世界五大死因之一，因此研究如何降低血清胆固醇含量已成为国际热点课题。植物乳杆菌的降胆固醇能力已得到国内外众多学者的公认，但其降解机理目前尚不明确，本研究运用蛋白质组学技术研究降胆固醇能力不同的植物乳杆菌差异表达蛋白，为植物乳杆菌降胆固醇机理的探讨提供科学的依据。实验对两株降胆固醇能力不同的植物乳杆菌M1和UVs29活化培养后测定胆固醇降解率，然后分别提取菌体蛋白，应用双向聚丙烯酰胺凝胶电泳技术分离样品中的蛋白质，银染显色获得差异表达蛋白点，并用基质辅助激光解析电离飞行时间质谱技术对其进行分析，结合NCBI数据库检索，鉴定这些差异表达蛋白。最后，应用生物信息学技术对差异蛋白进行GO分析和Pathway分析。本实验获得了降胆固醇能力不同的植物乳杆菌M1和UVs29差异表达蛋白的双向凝胶电泳图谱，利用质谱技术成功鉴定出24种差异表达蛋白，分别是30S核糖体蛋白S9、30S核糖体蛋白S4、烯醇化酶、热激蛋白Hsp20、腺嘌呤磷酸核糖转移酶、延长因子P、果糖-二磷酸醛缩酶、分子伴侣DnaK、腺苷酸激酶、30S核糖体蛋白S3、NADH过氧化物酶、丝氨酸羟甲基转移酶、乳清酸磷酸核糖转移酶、未知蛋白、TetR家族转录调控子、核糖体再循环因子、6-磷酸葡萄糖酸脱氢酶、延长因子Tu、S-核糖基同型半胱氨酸酶、烯酰-ACP还原酶、转录调节因子、尿嘧啶磷酸核糖转移酶、50S核糖体蛋白L1、核糖-磷酸焦磷酸激酶。通过生物信息学分析发现，其中烯醇化酶、烯酰-ACP还原酶、果糖-二磷酸醛缩酶、6-磷酸葡萄糖酸脱氢酶、核糖-磷酸焦磷酸激酶、未知蛋白、腺苷酸激酶、腺嘌呤磷酸核糖转移酶可能与植物乳杆菌降胆固醇能力有关系。本实验首次对降胆固醇能力不同的两株植物乳杆菌进行蛋白质组学研究，应用双向凝胶电泳和质谱技术分离并鉴定了24种差异表达蛋白，利用生物信息学技术研究了这些差异表达蛋白与植物乳杆菌降胆固醇能力可能存在的关系，这些差异表达蛋白及其在降胆固醇方面所产生的影响还需要更深入的验证。本实验对探明植物乳杆菌降胆固醇机理具有重要的指导意义。更多还原

【Abstract】 It is well known if the level of cholesterol is too high it will be harm to human body health,it is the main factor to induce cardiovascular disease, the cardiovascular disease has become oneof the world’s five leading cause of death, so it is the international hot subject about how toreduce serum cholesterol content. The cholesterol-lowering ability of Lactobacillus plantarumhave been recognized by many scholars at home and abroad, but its degradation mechanism isnot yet clear. This study we researched the differential expressed proteins of Lactobacillusplantarum of different cholesterol-lowering ability by proteomics technology. It can providescientific basis for the cholesterol-lowering mechanism of Lactobacillus plantarum.In this study, we test the cholesterol-lowering ability of Lactobacillus plantarum M1andLactobacillus plantarum UVs29, and then protein was extracted from the Lactobacillusplantarum M1and Lactobacillus plantarum UVs29. After sample proteins were separated bytwo-dimensional polyacrylamide gel electrophoresis, silwer stained gel imaging to get thedifferential expression proteins, then, the spots of the differential expression proteins wereanalyzed by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry(MALDI-TOF-MS) and the search of NCBI database, and then were analyzed online throughbioinformatics.Electrophoretogram of Lactobacillus plantarum M1and Lactobacillus plantarum UVs29were obtained by2-DE,24differential expressed proteins were separated and identified byMALDI-TOF-MS, and results showed that these proteins are30S ribosomal protein S9,enolase,30S ribosomal protein S4, adenine phosphoribosyltransferase, heat shock proteinHsp20,elongation factor P,fructose-bisphosphate aldolase,molecular chaperone DnaK,adenylatekinase,30S ribosomal protein S3,NADH peroxidase,serine hydroxymethyltransferase,orotatephosphoribosyltransferase, TetR family transcriptional regulator,Ribosome-recycling factor,unnamed protein product,UTP-glucose-1-phosphate uridylyltransferase,6-phosphogluconatedehydrogenase, enoyl-ACP reductase,Elongation factor Tu,S-ribosylhomocysteine lyase,transcriptional regulator,uracil phosphoribosyltransferase, ribose-phosphate pyrophosphokinase,50S ribosomal protein L1.In this study, we first explore two strains of Lactobacillus plantarum of different cholesterol-lowering ability by proteomics. Two-dimensional gel electrophoresis and massspectrometry were used to separate and identify the24differential expressed proteins. Thendiscuss the relationship between these differential expressed proteins and cholesterol-loweringability of Lactobacillus plantarum， however, it need to verify these proteins and theirrelationship with cholesterol-lowering ability in the future. This experiment had very importantguiding meaning of ascertain the cholesterol-lowering mechanism of Lactobacillus plantarum.更多还原