中山大学 生物工程制药 漏题答案.doc

中山大学生命科学学院生物工程与制药 试卷A答案Pharmaceutical Biotechnology Examination Paper任课老师：刘秋云 考试时间：2009-7-9（ 2008 学年 第 2 学期 系 专业）考生姓名学号 一二三四五总 分注: 1.请将全部答案写在答题纸上;2.可用中文、英文或中英文答题;3.请将试卷和答题纸一起交回。Part A：Briefly describe or give definitions to the following questions or terms: (4 points for each term, total 20 points)(简答题)1 Humanized antibody （人源化抗体）将小鼠的CDR（抗原结合区）整合至人源抗体中，约10%为小鼠，具有低的免疫原性，更长的血清半衰期，较轻的过敏反应。2 Phage Display （噬菌体显示）将外源基因片段插在噬菌体外壳蛋白基因中，表达在噬菌体的表面，以研究相互作用的受体、蛋白质及抗原、抗体。31.3 The consensus sequence of yeast glycosylation sites （酵母通常的糖基化位点的氨基酸序列）Asn X Ser/Thr、Ser、Thr4 Inclusion bodies （包涵体）包涵体是指细菌表达的蛋白在细胞内凝集，形成无活性的固体颗粒。主要因为在重组蛋白的表达过程中缺乏某些蛋白质折叠的辅助因子，或环境不适，无法形成正确的次级键等原因形成的。5 How many different 4bp palindromic sequences are there and why? （识别序列为4碱基的回文序列有几种？简单加以解释）16First 2 bp reverse and complement last 2 bp.Part B：Essay questions (20 points for each question, and choose 4 out of 6 questions. Total 80 points) (问答题，任选4题)2. How to use a directed evolution technique to improve a proteins stability or activity? 怎样用定向进化技术改造一个药用蛋白的稳定性或活性？首先进行出错PCR（加Mn离子、非保真性聚合酶、不平衡dNTP）、DNA shuffling 或Staggered extension process, 制造突变体库。然后在不同的条件下进行筛选。3. What is the N-end rule in gene expression in E. coli? Why is leucine in the penultimate position a poor choice? 什么是大肠杆菌基因表达的N-端规则？为什么蛋白质的第二个残基为亮氨酸时对于大肠杆菌基因表达是一个不好的设计？A factor that appears to influence target protein stability is the amino acid immediately following the N-terminal methionine (penultimate amino acid). The amino acid at this position determines the removal of N-terminal fMet. little or no processing was observed when the following amino acids occupied the penultimate position: His, Gln, Glu, Phe, Met, Lys, Tyr, Trp, Arg. Processing ranged from 16%97% when the remaining amino acids occupied this position. Scientists reported protein half-lives of only 2 minutes when the following amino acids were present at the amino terminus: Arg, Lys, Phe, Leu, Trp, and Tyr. In contrast, all other amino acids conferred half-lives of 10 hours when present at the amino terminus in the protein examined. these studies suggest that Leu in the penultimate position would be a poor choice, because it would likely be exposed by fMet processing and then be targeted for rapid degradation. 434567 . 8 What is attenuated vaccine? What is recombinant protein vaccine?什么是减毒疫苗？什么是重组蛋白疫苗？减毒疫苗即毒力减弱的活疫苗。可通过两个途径得到。一是将人的病毒接种猴子细胞，传种多代获得适应性突变，再做人疫苗毒力将会减弱。二是敲掉细菌或病毒的某些基因而使毒力减弱，再做人疫苗。重组蛋白疫苗即用基因工程方法生产重组蛋白，纯化后再作为疫苗。5. What is SNP (single nucleotide polymorphisms)? Why are cytochrome P450 polymorphisms used in the drug screening process by pharmaceutical companies? 请描述分子标记SNP的原理。为什么细胞色素P450被制药公司用在了药物研发过程？基因组上广泛分布的单个核苷酸的改变，会出现在编码区和非编码区，平均1250bp出现一个SNP。SNP多态性会导致遗传病或与遗传病基因连锁。P450与药物代谢、药物反应等有关，具有SNP多态性，并表现出不同的表型，对药物反应效率与副作用等密切相关，因此P450被制药公司用在了药物研发过程，对SNP的综合分析将能够针对不同人群对症治疗。6. Please describe the principle of a next-generation sequencing technology.请描述一超高通量测序技术的原理。Solexa sequencing technology relies on attachment of randomly fragmented genomic DNA to a planar, optically transparent surface and solid phase amplification to create an ultra-high density sequencing flow cell with 10 million clusters, each containing 1,000 copies of template per sq. cm. These templates are sequenced using a robust four-color DNA sequencing-by-synthesis technology that employs reversible terminators with removable fluorescence. 7. Describe the technique for cre