QM/MM Study of the Uracil DNA Glycosylase Reaction Mechanism: A Competition between Asp145 and His148.
[No authors listed]
摘要
Uracil DNA glycosylase catalyzes the N-glycosidic bond cleavage of uracil, thereby initiating the base excision repair mechanism for this DNA lesion. Here we employ hybrid quantum mechanics/molecular mechanics calculations to investigate the exact mechanism of the nucleophile attack and the role of the conserved His148 residue. Our calculations suggest that the C1'-N1 bond dissociation proceeds by a migration of the electrophilic sugar in the direction of the water nucleophile, resulting in a planar, oxocarbenium-like transition state. The subsequent nucleophile addition and proton transfer to a nearby base occur without a barrier. We assign the role of a proton acceptor to His148 and elucidate why mutations of this residue curtail the enzymatic activity but do not fully suppress it.
KEYWORDS: {{ getKeywords(articleDetailText.words) }}
基因功能
- {{$index+1}}.{{ gene }}
原始数据
| Sample name | Organism | Experiment title | Sample type | Library instrument | Attributes | |||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| {{attr}} | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
| {{ dataList.sampleTitle }} | {{ dataList.organism }} | {{ dataList.expermentTitle }} | {{ dataList.sampleType }} | {{ dataList.libraryInstrument }} | {{ showAttributeName(index,attr,dataList.attributes) }} | |||||||||||||||||||||||||||||||||||||||||||||||||
文献解读
| {{ list.authorName }} {{ list.authorName }} |
