相关实验视频
Updated: Jan 26, 2026

08:26
Analysis of N-glycans from Raphanus sativus Cultivars Using PNGase H+
Published on: June 25, 2018
7.1K
控制免疫性鞭毛蛋白的水解释放
Pierre Buscaill1, Balakumaran Chandrasekar1, Nattapong Sanguankiattichai1
1Department of Plant Sciences, University of Oxford, Oxford, UK.
概括
植物的免疫系统可以检测细菌的鞭毛蛋白, 但它的释放需要特定的酶. 我们发现植物β-银酶1 (BGAL1) 释放这些碎片, 对于植物对某些细菌病原体的免疫力至关重要.
科学领域:
- 植物病原体相互作用
- 分子免疫学
- 细菌的糖化
背景情况:
- 植物和动物具有检测保存的鞭毛蛋白碎片的免疫机制,表明细菌入侵.
- 旗素片段,免疫诱导,嵌入在旗素聚合物中,需要水解释放来激活宿主细胞表面受体.
- 控制这些免疫性鞭片段释放的精确机制在很大程度上仍未被描述.
研究的目的:
- 研究植物酶在免疫性鞭毛蛋白碎片的水解释放中的作用.
- 阐明特定的细菌因素和宿主成分参与植物对鞭毛菌的免疫力.
- 了解细菌的反防御策略,以鞭毛蛋白识别为媒介的植物免疫反应.
主要方法:
- 在鞭毛蛋白加工过程中涉及的植物分泌酶的识别和表征.
- 在致病性*Pseudomonas syringae*菌株中分析鞭毛蛋白O-甘氨酸结构.
- 试验是为了评估植物β-银酶1 (BGAL1) 和细菌鞭毛蛋白之间的相互作用.
- 对具有不同鞭糖化模式的P. syringae菌株进行植物免疫反应的评估.
主要成果:
- 发现Nicotiana benthamiana* β-galactosidase 1 (BGAL1) 是一种促进鞭毛蛋白释放的关键酶.
- BGAL1介导的免疫对具有终端修饰的viosamine (mVio) 的P. syringae菌株有效.
- *P. syringae* 种类已经进化了反防御机制,包括抗BGAL1的O- glycans和BGAL1抑制剂,以逃避宿主免疫力.
结论:
- 植物β-银酶1 (BGAL1) 通过释放免疫性鞭毛蛋白碎片,在植物免疫性中发挥关键作用.
- 细菌鞭毛体的糖化状态,特别是mVio的存在,决定了它们对BGAL1等宿主酶的识别和敏感性.
- 细菌鞭状甘氨酸是宿主免疫的重要决定因素,病原体采用各种策略来调节这些结构以逃避免疫.
相关概念视频
Phase I Reactions: Hydrolytic Reactions
648
Hydrolysis, a cornerstone of phase I biotransformation reactions, uses water to cleave chemical bonds. This process is pivotal in drug metabolism, generating more polar metabolites that can be easily excreted.
An important hydrolytic reaction is ester hydrolysis. Ester bonds, often found in prodrugs, are broken down, increasing the solubility of drugs like aspirin and lidocaine for more straightforward elimination. Amide hydrolysis is another critical reaction, targeting amide bonds prevalent...
An important hydrolytic reaction is ester hydrolysis. Ester bonds, often found in prodrugs, are broken down, increasing the solubility of drugs like aspirin and lidocaine for more straightforward elimination. Amide hydrolysis is another critical reaction, targeting amide bonds prevalent...
648
Peptide Bonds
82.6K
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
82.6K
Single Nucleotide Polymorphisms-SNPs
18.0K
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
18.0K
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
686
Polymorphism refers to the existence of a drug substance in multiple crystalline forms, known as polymorphs. Recently, this term has been expanded to include solvates (forms containing a solvent), amorphous forms (non-crystalline forms), and desolvated solvates (forms from which the solvent has been removed).
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
686
Energy-releasing Steps of Glycolysis
146.5K
Glycolysis is divided into two phases based on whether energy is utilized or released. While the first phase consumes ATP, the second phase produces energy in the form of ATP and NADH. The energy is released over a sequence of reactions that turns G3P into pyruvate. The energy-releasing phase—steps 6-10 of glycolysis—occurs twice, once for each of the two 3-carbon sugars produced during steps 1-5 of the first phase.
The first energy-releasing step—the 6th step of glycolysis...
The first energy-releasing step—the 6th step of glycolysis...
146.5K
Pharmaceutical Alternatives: Polymorphic Form-Related and Particle Size-Related Therapeutic Nonequivalence
163
Changes in polymorphic forms can significantly influence the bioavailability of poorly soluble drugs. Although the FDA defines pharmaceutical equivalence based on having the same active ingredient, dosage form, and route of administration, it does not automatically disqualify products with different polymorphic forms. This means two products with different polymorphs can still be deemed pharmaceutically equivalent. However, polymorphic differences can affect properties like wettability,...
163

