Allosteric Influence of Extremophile Hairpin Motif Mutations on the Protein Splicing Activity of a Hyperthermophilic Intein
| Autor: | Angel Chavez, Jennifer M. Pusztay, Kathryn C Chiarolanzio, Jian Xie, Chunyu Wang, Jing Zhao, Kenneth V. Mills |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Pyrococcus abyssi
0303 health sciences biology Chemistry Archaeal Proteins DNA polymerase II Amino Acid Motifs 030302 biochemistry & molecular biology Allosteric regulation Active site DNA Polymerase II biology.organism_classification Biochemistry Article Hyperthermophile Inteins 03 medical and health sciences Protein splicing RNA splicing biology.protein Protein Splicing Intein |
| Zdroj: | Biochemistry |
| ISSN: | 1520-4995 0006-2960 |
| DOI: | 10.1021/acs.biochem.0c00348 |
| Popis: | Protein splicing is a post-translational process mediated by an intein, whereby the intein excises itself from a precursor protein with concomitant ligation of the two flanking polypeptides. The intein that interrupts the DNA polymerase II in the extreme hyperthermophile Pyrococcus abyssi has a β-hairpin that extends the central β-sheet of the intein. This β-hairpin is mostly found in inteins from archaea, as well as halophilic eubacteria, and is thus called the extremophile hairpin (EXH) motif. The EXH is stabilized by multiple favorable interactions, including electrostatic interactions involving Glu29, Glu31, and Arg40. Mutations of these residues diminish the extent of N-terminal cleavage and the extent of protein splicing, likely by interfering with the coordination of the steps of splicing. These same mutations decrease the global stability of the intein fold as measured by susceptibility to thermolysin cleavage. 15N-1H heteronuclear single-quantum coherence demonstrated that these mutations altered the chemical environment of active site residues such as His93 (B-block histidine) and Ser166 (F-block residue 4). This work again underscores the connected and coordinated nature of intein conformation and dynamics, where remote mutations can disturb a finely tuned interaction network to inhibit or enhance protein splicing. |
| Databáze: | OpenAIRE |
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