アナーロビック・ヒドロキシプロリン分解は,グリシル・ラジカル酵素によるC-N分裂を含む
Yongxu Duan1,2, Yifeng Wei3, Meining Xing1,2
1Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China.
Journal of the American Chemical Society
|May 25, 2022
まとめ
研究者らは新しい無酸素ヒドロキシプロリン分解経路を発見し,新しいグリシル基酵素 (GRE),HplGを含む. この酵素は,トランス-4-ヒドロキシ-d-プロリン (t4D-HP) のリング開きを促進し,重要な代謝産物を生成し,無酸素細菌における多様な酵素基化学を明らかにします.
科学分野:
- 生物化学
- 微生物学
- 酵素学
背景:
- ハイドロキシプロリンは自然に豊富に存在し,構造タンパク質の成分とオスモライトとして機能する.
- トランス - 4 - ヒドロキシ - 1 - プロリン (t4L- HP) の無酸素分解は,グリシル基酵素 (GRE) HypDが関与することが知られている.
研究 の 目的:
- アナーロビックヒドロキシプロリンの分解のための新しい経路を明らかにする.
- この経路に関与する新しいGRE,trans-4-hydroxy-d-proline (t4D-HP) C-N-lyase (HplG) を特徴付ける.
主な方法:
- 酵素の特徴と構造分析
- 2.7 Åの解像度でt4D-HPと複合したHplGの結晶学.
- HplGを含む細菌種を特定する.
主要な成果:
- HplGを含む新しい無酸素ヒドロキシプロリン分解経路が特定されました.
- HplGは,2-アミノ-4-ケトペンタノアート (AKP) へのt4D-HPの根幹媒介のリング開きを触媒化し,GRE 1,2-エリミナーゼ反応である.
- HplGの結晶構造はメカニズム的な洞察を提供します.
- HplGは様々な発酵細菌に存在し,Clostridiaに存在するHypDとは異なる.
結論:
- HplGは,ヒドロキシプロリン分解に関与する新しいGREを表します.
- この経路は無酸素微生物の 酵素の化学反応の理解を広げています
- HplGの分布は,バクテリアの代謝戦略の多様性を強調しています.
関連する概念動画
01:18Amino Acid Catabolism
222
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
222
01:08Nitriles to Carboxylic Acids: Hydrolysis
4.1K
Nitriles undergo acid-catalyzed hydrolysis or base-catalyzed hydrolysis to form a carboxylic acid. These reactions proceed via an amide intermediate.
4.1K
01:15Hydrolysis
116.7K
Overview
Hydrolysis is a chemical reaction in which the addition of water breaks down a polymer into its simpler monomer units. For example, peptides break into amino acids, carbohydrates into simple sugars, and DNA into nucleotides. Enzymes often facilitate these processes.
Hydrolysis Reverses Dehydration Synthesis
Complex carbohydrates can be broken down by breaking the bonds between individual sugar units. The reaction breaks a glycosidic bond as water is added to the compound. The...
Hydrolysis is a chemical reaction in which the addition of water breaks down a polymer into its simpler monomer units. For example, peptides break into amino acids, carbohydrates into simple sugars, and DNA into nucleotides. Enzymes often facilitate these processes.
Hydrolysis Reverses Dehydration Synthesis
Complex carbohydrates can be broken down by breaking the bonds between individual sugar units. The reaction breaks a glycosidic bond as water is added to the compound. The...
116.7K
01:01Acid Halides to Carboxylic Acids: Hydrolysis
2.9K
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
2.9K
01:28Amides to Carboxylic Acids: Hydrolysis
3.5K
Amides can undergo either acid-catalyzed hydrolysis or base-promoted hydrolysis through a typical nucleophilic acyl substitution. Each hydrolysis requires severe conditions.
Acid-catalyzed hydrolysis:
Hydrolysis of amides under acidic conditions yields carboxylic acids. Since the reaction occurs slowly, hydrolysis requires the conditions of heat.
The mechanism begins with the protonation of the carbonyl oxygen by the acid catalyst. The protonation makes the amide carbonyl carbon more...
Acid-catalyzed hydrolysis:
Hydrolysis of amides under acidic conditions yields carboxylic acids. Since the reaction occurs slowly, hydrolysis requires the conditions of heat.
The mechanism begins with the protonation of the carbonyl oxygen by the acid catalyst. The protonation makes the amide carbonyl carbon more...
3.5K
01:10Aldehydes and Ketones with HCN: Cyanohydrin Formation Mechanism
3.4K
Cyanohydrins are formed when cyanide nucleophiles and carbonyl compounds like aldehydes and ketones react. A strong base, the cyanide ion, catalyzes cyanohydrin formation. The ions are generated from HCN under aqueous conditions. Once the cyanide ions are generated, the first step involves the nucleophilic attack of the cyanide ions on the electrophilic carbonyl carbon. This attack shifts the π electrons from the C=O to the oxygen atom forming the alkoxide ion intermediate. The alkoxide anion...
3.4K