编码子优化对Escherichia coli蛋白质编码DNA序列表达的作用,这些序列来自原生动物Eimeria
Mark C Jenkins1, Carolyn Parker1, Celia O'Brien1
1Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, NEA, ARS, USDA, United States of America.
Journal of microbiological methods
|June 4, 2023
概括
对于大肠杆菌中重组蛋白质表达的Codon优化并不总是增加Eimeria基因的产量. 分析揭示了与蛋白质结构无关的复杂的编码子使用模式,表明其他因素影响表达.
科学领域:
- 分子生物学分子生物学
- 寄生虫学的寄生虫学
- 生物技术是生物技术.
背景情况:
- 再组合蛋白质的生产对于研究和治疗至关重要.
- 埃梅里亚寄生虫对牲畜造成重大经济损失.
- 在大肠杆菌等宿主系统中优化基因表达对于高效的蛋白质生产至关重要.
研究的目的:
- 评估编码子优化对大肠杆菌中Eimeria基因的重组蛋白产量的影响.
- 调查Eimeria中的codon使用模式及其与蛋白质结构和表达水平的潜在关系.
主要方法:
- 克隆Eimeria基因序列 (EmaxSO7,EmaxIMP1,EAH00033530) 有或没有编码子优化.
- 在大肠杆菌中聚His融合蛋白的表达.
- 再组合蛋白质水平的量化.
- 分析基因序列内的编码子使用频率和分布.
主要成果:
- 子优化并不总是导致重组蛋白的产量增加;观察到更高,更低和不变的产量.
- 艾梅里亚基因序列表现出罕见和经常使用的密码子的混合,类似于其他生物体.
- 预测的蛋白质结构和常见或罕见的编码子的分布之间没有发现相关性.
结论:
- 仅仅是Codon优化并不是提高Eimeria重组蛋白表达在E. coli中的保证策略.
- 艾梅里亚的密码子使用受到区域二次蛋白质结构以外的因素的影响,这表明复杂的调节机制.
相关概念视频
Leaky Scanning
5.2K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.2K
Improving Translational Accuracy
11.7K
Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
11.7K
From DNA to Protein
18.6K
The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis...
18.6K
The Central Dogma
127.2K
Overview
127.2K
Stringent Response in E. coli
32
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
32
What is Gene Expression?
8.6K
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is comprised of nucleotides and proteins are comprised of amino acids, a mediator is required to convert the information encoded in DNA into proteins. This mediator is the messenger RNA (mRNA). mRNA copies the blueprint from DNA by a process called transcription. In eukaryotes, transcription occurs in the nucleus by complementary base-pairing with the DNA template. The mRNA is then...
8.6K


