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Protein folding. James Dewey Wason Francis Harry Compton Crick. DNA RNA Proein. ?. 中国启动人类肝脏 蛋白质组计划. 国际人类蛋白质组计划的20%以上的任务。. proteomics. 为什么要开展 蛋白质 折叠 的研究 ?. dis ease. 免 疫. 病毒. 研究的源动力. Protein folding & live. 吴 宪 1893,11,24---1959,8,8. 蛋白质研究先驱.
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James Dewey Wason Francis Harry Compton Crick
中国启动人类肝脏 蛋白质组计划 国际人类蛋白质组计划的20%以上的任务。 proteomics
disease 免 疫 病毒 研究的源动力
吴 宪 1893,11,24---1959,8,8 蛋白质研究先驱
1912年到美国麻省理工学院。因愤于我国海军落后,初学造船工程。因受赫胥黎“生命的物理基础”一文的影响,2年后改习化学。1916年毕业,获理学学士学位,留校任化学系助教。1917年进哈佛大学医学院生物系,成为美国著名生物化学家 Folin教授的研究生,进行血液化学研究。1924年起用各种方法使蛋白质变性,1931年得出如下理论:蛋白质的变性是由于蛋白质分子由折叠而变为舒展。
ribonuclease 变性剂 巯基 乙醇 复性
denatured molecule Some denatured proteins can be renatured Anfinsen原理 1961
Probability that correct folding would occur in ribonuclease given that there are8 cysteine residues 1/7 x 1/5 x 1/3 x 1 = 1/105 expected activity~ 1% observed activity was100%
if one conformation is explored every 0.1 psec, then time to refold (t) = 1087 sec Mechanisms to explain re-folding Factors driving protein folding • 2n torsion angles can have 32n ~ 10npossible conformations • if n =100, then number of conformations, 10100 • directed pathways of folding must exists
Framework model Formation of elements of 2-stru. Assembly of 2-stru. Folded con. Unfolded state
GCN4 leucine zipper gabcdefgabcdefgabcdefgabcdefgabcd STHMKQLEDKVEELLSKNYHLENEVARLKKLVGER
CD spectra of GCN4 leucine zipper in the presence of different concentrations of SDS 4 M GuHCl SDS
Changes of ellipticity at 222 nm in the presence of different concentrations of SDS
Native gel electrophoresis of leucine zipper treated with SDS of different concentrations Lane 1 was the native leucine zipper peptide (control); lanes 2- 6 were samples treated with 0.1, 0.2, 0.3, 0.6, and 1.0 mM SDS
Energy surfaces to visualize protein folding pathways a more realistic energy landscape A the protein is funneled towards a native state many pathways are possible some lead straight downhill others may lead to energy minima that delay proper folding
Changes of fluorescence emission spectra of Tg denatured in various concentrations of GuHCl Thyroglobulin
ANS binding characteristics of Tg in various GuHCl concentrations
酶活性部位的柔性学说 邹承鲁
Protein–protein interface design
EPO-EPOR ERPH1-EPOR LiuS,LiuSY,ZhuXL, LiangHH,CaoAN,ChangZJandLaiLH*. Nonnaturalprotein-proteininteraction-pairdesignbykeyresiduesgrafting. PNAS,2007,104,5330
抗氧化剂对A1-40结构的影响 庾照学等,中国病理生理杂志,2000,16 FT - IR spectra of A1 - 40 in PBS(pH7. 4) for 30min FT - IR spectra of A1 - 40 in PBS(pH7. 4) for 7 days
FT- IR spectra of A1 - 40in PBS(pH7. 4) with TA9901 for 7 days (percent ratio : A1 – 40 :TA9901 = 1∶1) FT - IR spectra of A1 - 40 in PBS(pH7. 4) for 7 days
衰 减 全 反 射 红 外 光 谱 研究人乳腺癌组织
记忆合金棒矫正脊柱侧凸 卢世璧 (院士) HSP 肿瘤疫苗
新生肽链的折叠 分子伴侣molecular chaperones
疯牛病带给生命科学界的思考 Mad cow TSE
Alzheimer’s D. Amyloid Protein & Tau protein Conformational Brains Disorders Parkinson D. α-synuclein Huntington D. Glutamine-repeat Protein Conforma- tional Disorders (PCD) Prion D. Prion protein Sickle cell anaemiaHaemoglobin Familial visceral Amyloidosis Lysozyme ….
Human Prion Diseases • Sporadic form Creutzfeldt-Jakob disease (CJD) • Familial (inherited) form Familial CJD Fatal familial insomnia Gerstmann-Straussler-Scheinker syndrome • Acquired (transmitted) form Iatrogenic CJD Kuru New Variant CJD (related to Mad Cow Disease)
Animal Prion Diseases • Scrapie Sheep and goat • Bovine spongiform encephalopathy (Mad Cow Disease) Cattle • Feline spongiform encephalopathy Cat (domestic cats, cheetahs, pumas) • Transmissible mink encephalopathy Mink • Chronic wasting disease Mule deer, elk
朊病毒(Prion)病的共同特征 病理学上的特点: 大脑皮层的神经原细胞退化、空泡变性、死亡、消失, 星状胶质细胞增生,蛋白酶抗性的PrP积聚,有时产生淀 粉样斑 临床表现: 痴呆、共剂失调、震颤等症状
Prion Protein Gene (PRNP) ---Located on chromosome 20 in humans, chromosome 2 in mouse ---Encodes a glycoprotein with two sites for N-linked oligosaccharites and a C-terminal GPI anchor ---High expression in brain. Lower expression in peripheral tissues ---~10-15% of all cases are familial. About 20 mutations are linked to familial disease.
The Nobel Prize in Physiology or Medicine 1976for their discoveries concerning new mechanisms for the origin and dissemination of infectious diseases Baruch S. Blumberg D. Carleton Gajdusek
Stanley B. PrusinerThe Nobel Prize in Physiology or Medicine 1997for his discovery of Prions - a new biological principle of infection
transcription translation DNA RNA Protein folding Sequence structure function 二个中心法则 1. Genetics: 中心法则? 2. Protein:
PrPcPrPsc Conformational transition: from alpha-helix rich to beta-sheet rich
PrPsc PrP27-30 PrPc
References • Roger H.Pain, Mechanisms of Protein Folding • Bengt Nölting, Proein Folding Kinetics –Biophysical Methods • Leninger, Principles of Biochemistry,Worth Publishing, • Mathews and Van Holde, Biochemistry, Benjamin Cummings