論文 - 詳細
| RRC ID | 76835 |
|---|---|
| 著者 | Zhi-Min Li, Ziwei Hu, Xiaoqin Wang, Suhang Chen, Weiyan Yu, Jianping Liu, Zhimin Li |
| タイトル | Biochemical and Structural Insights into a Thiamine Diphosphate-Dependent α-Ketoglutarate Decarboxylase from Cyanobacterium Microcystis aeruginosa NIES-843 |
| ジャーナル | International Journal of Molecular Sciences |
| Abstract |
α-Ketoglutarate decarboxylase is a crucial enzyme in the tricarboxylic acid cycle of cyanobacteria, catalyzing the non-oxidative decarboxylation of α-ketoglutarate to produce succinate semialdehyde and CO2. The decarboxylation process is reliant on the cofactor of thiamine diphosphate. However, this enzyme’s biochemical and structural properties have not been well characterized. In this work, two α-ketoglutarate decarboxylases encoded by MAE_06010 and MiAbw_01735 genes from Microcystis aeruginosa NIES-843 (MaKGD) and NIES-4325 (MiKGD), respectively, were overexpressed and purified by using an Escherichia coli expression system. It was found that MaKGD exhibited 9.2-fold higher catalytic efficiency than MiKGD, which may be attributed to the absence of glutamate decarboxylase in Microcystis aeruginosa NIES-843. Further biochemical investigation of MaKGD demonstrated that it displayed optimum activity at pH 6.5–7.0 and was most activated by Mg2+. Additionally, MaKGD showed substrate specificity towards α-ketoglutarate. Structural modeling and autodocking results revealed that the active site of MaKGD contained a distinct binding pocket where α-ketoglutarate and thiamine diphosphate interacted with specific amino acid residues via hydrophobic interactions, hydrogen bonds and salt bridges. Furthermore, the mutagenesis study provided strong evidence supporting the importance of certain residues in the catalysis of MaKGD. These findings provide new insights into the structure-function relationships of α-ketoglutarate decarboxylases from cyanobacteria. |
| 巻・号 | 24 |
| ページ | 12198 |
| 公開日 | 2023-7-30 |
| DOI | 10.3390/ijms241512198 |
| PMID | 37569577 |
| PMC | PMC10418658 |
| MeSH | Carboxy-Lyases* / metabolism Ketoglutaric Acids / metabolism Microcystis* / genetics Thiamine Pyrophosphate / metabolism |
| IF | 4.556 |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | Patent(IFI CLAIMS) |
| 各媒体での言及数の合計 | 1 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 藻類 | NIES-843 |