1
|
Bian M, Zhao J, Xu W, Han X, Chen X, Wang P, Zhu G. Enzymatic Characterization of the Isocitrate Dehydrogenase with Dual Coenzyme Specificity from the Marine Bacterium Umbonibacter marinipuiceus. Int J Mol Sci 2023; 24:11428. [PMID: 37511187 PMCID: PMC10380307 DOI: 10.3390/ijms241411428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/07/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Isocitrate dehydrogenase (IDH) can be divided into NAD+-dependent and NADP+-dependent types based on the coenzyme specificity. It is worth noting that some IDHs exhibit dual coenzyme specificity characteristics. Herein, a dual coenzyme-dependent IDH from Umbonibacter Marinipuiceus (UmIDH) was expressed, purified, and identified in detail for the first time. SDS-PAGE and Gel filtration chromatography analyses showed that UmIDH is an 84.7 kDa homodimer in solution. The Km values for NAD+ and NADP+ are 1800.0 ± 64.4 μM and 1167.7 ± 113.0 μM in the presence of Mn2+, respectively. Meanwhile, the catalytic efficiency (kcat/Km) of UmIDH is only 2.3-fold greater for NADP+ than NAD+. The maximal activity for UmIDH occurred at pH 8.5 (with Mn2+) or pH 8.7 (with Mg2+) and at 35 °C (with Mn2+ or Mg2+). Heat inactivation assay revealed that UmIDH sustained 50% of maximal activity after incubation at 57 °C for 20 min with either Mn2+ or Mg2+. Moreover, three putative core coenzyme binding residues (R345, L346, and V352) of UmIDH were evaluated by site-directed mutagenesis. This recent work identified a unique dual coenzyme-dependent IDH and achieved the groundbreaking bidirectional modification of this specific IDH's coenzyme dependence for the first time. This provides not only a reference for the study of dual coenzyme-dependent IDH, but also a basis for the investigation of the coenzyme-specific evolutionary mechanisms of IDH.
Collapse
Affiliation(s)
- Mingjie Bian
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Jiaxin Zhao
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Wenqiang Xu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Xueyang Han
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Xuefei Chen
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Peng Wang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| | - Guoping Zhu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, Anhui Normal University, Wuhu 241000, China
| |
Collapse
|
2
|
Expression, purification, and biochemical characterization of an NAD +-dependent homoserine dehydrogenase from the symbiotic Polynucleobacter necessarius subsp. necessarius. Protein Expr Purif 2021; 188:105977. [PMID: 34547433 DOI: 10.1016/j.pep.2021.105977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 11/21/2022]
Abstract
Homoserine dehydrogenase (HSD), encoded by the hom gene, is a key enzyme in the aspartate pathway, which reversibly catalyzes the conversion of l-aspartate β-semialdehyde to l-homoserine (l-Hse), using either NAD(H) or NADP(H) as a coenzyme. In this work, we presented the first characterization of the HSD from the symbiotic Polynucleobacter necessaries subsp. necessarius (PnHSD) produced in Escherichia coli. Sequence analysis showed that PnHSD is an ACT domain-containing monofunctional HSD with 436 amnio acid residues. SDS-PAGE and Western blot demonstrated that PnHSD could be overexpressed in E. coli BL21(DE3) cell as a soluble form by using SUMO fusion technique. It could be purified to apparent homogeneity for biochemical characterization. Size-exclusion chromatography revealed that the purified PnHSD has a native molecular mass of ∼160 kDa, indicating a homotetrameric structure. The oxidation activity of PnHSD was studied in this work. Kinetic analysis revealed that PnHSD displayed an up to 1460-fold preference for NAD+ over NADP+, in contrast to its homologs. The purified PnHSD displayed maximal activity at 35 °C and pH 11. Similar to its NAD+-dependent homolog, neither NaCl and KCl activation nor L-Thr inhibition on the enzymatic activity of PnHSD was observed. These results will contribute to a better understanding of the coenzyme specificity of the HSD family and the aspartate pathway of P. necessarius.
Collapse
|
3
|
Tang W, Wu M, Qin N, Liu L, Meng R, Wang C, Wang P, Zang J, Zhu G. Crystal structures of NAD +-linked isocitrate dehydrogenase from the green alga Ostreococcus tauri and its evolutionary relationship with eukaryotic NADP +-linked homologs. Arch Biochem Biophys 2021; 708:108898. [PMID: 33957092 DOI: 10.1016/j.abb.2021.108898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 11/20/2022]
Abstract
NAD+-linked isocitrate dehydrogenases (NAD-IDHs) catalyze the oxidative decarboxylation of isocitrate into α-ketoglutarate. Previously, we identified a novel phylogenetic clade including NAD-IDHs from several algae in the type II subfamily, represented by homodimeric NAD-IDH from Ostreococcus tauri (OtIDH). However, due to its lack of a crystalline structure, the molecular mechanisms of the ligand binding and catalysis of OtIDH are little known. Here, we elucidate four high-resolution crystal structures of OtIDH in a ligand-free and various ligand-bound forms that capture at least three states in the catalytic cycle: open, semi-closed, and fully closed. Our results indicate that OtIDH shows several novel interactions with NAD+, unlike type I NAD-IDHs, as well as a strictly conserved substrate binding mode that is similar to other homologs. The central roles of Lys283' in dual coenzyme recognition and Lys234 in catalysis were also revealed. In addition, the crystal structures obtained here also allow us to understand the catalytic mechanism. As expected, structural comparisons reveal that OtIDH has a very high structural similarity to eukaryotic NADP+-linked IDHs (NADP-IDHs) within the type II subfamily rather than with the previously reported NAD-IDHs within the type I subfamily. It has also been demonstrated that OtIDH exhibits substantial conformation changes upon ligand binding, similar to eukaryotic NADP-IDHs. These results unambiguously support our hypothesis that OtIDH and OtIDH-like homologs are possible evolutionary ancestors of eukaryotic NADP-IDHs in type II subfamily.
Collapse
Affiliation(s)
- Wanggang Tang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China; Department of Biochemistry and Molecular Biology, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Minhao Wu
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Na Qin
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China
| | - Li Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China
| | - Rui Meng
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China
| | - Chengliang Wang
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Peng Wang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China.
| | - Jianye Zang
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, China.
| | - Guoping Zhu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases and Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, No.1 Beijing East Road, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China.
| |
Collapse
|
4
|
Huang S, Zhao J, Li W, Wang P, Xue Z, Zhu G. Biochemical and Phylogenetic Characterization of a Novel NADP +-Specific Isocitrate Dehydrogenase From the Marine Microalga Phaeodactylum tricornutum. Front Mol Biosci 2021; 8:702083. [PMID: 34291089 PMCID: PMC8287583 DOI: 10.3389/fmolb.2021.702083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/24/2021] [Indexed: 11/13/2022] Open
Abstract
Isocitrate dehydrogenase (IDH) family of proteins is classified into three subfamilies, namely, types I, II, and III. Although IDHs are widely distributed in bacteria, archaea, and eukaryotes, all type III IDHs reported to date are found only in prokaryotes. Herein, a novel type III IDH subfamily member from the marine microalga Phaeodactylum tricornutum (PtIDH2) was overexpressed, purified, and characterized in detail for the first time. Relatively few eukaryotic genomes encode this type of IDH and PtIDH2 shares the highest homology with marine bacterial monomeric IDHs, suggesting that PtIDH2 originated through a horizontal gene transfer event between a marine alga and a bacterium. Size-exclusion chromatography revealed that the native PtIDH2 is a homotetramer (∼320 kDa) in solution, comprising four monomeric IDH-like subunits (80 kDa each). Enzymatic characterization showed that PtIDH2 is a bivalent metal ion-dependent enzyme and Mn2+ is the optimal activator. The recombinant PtIDH2 protein exhibited maximal activity at 35°C and pH 8.0 in the presence of Mn2+. Heat-inactivation analysis revealed that PtIDH2 is a cold-adapted enzyme. Kinetic analysis demonstrated that PtIDH2 is a completely NADP+-specific IDH with no detectable NAD+-associated catalytic activity. The three putative key NADP+-binding residues (His604, Arg615, and Arg664) in PtIDH2 were also evaluated by site-directed mutagenesis. The H604L/R615D/R664S triple mutant showed a 3.25-fold preference for NAD+ over NADP+, implying that the coenzyme specificity of PtIDH2 can be converted from NADP+ to NAD+ through rational engineering approaches. Additionally, the roles of the conserved residues Ala718 and Leu742 in the thermostability of PtIDH2 were also explored by site-directed mutagenesis. We found that the L742F mutant displayed higher thermostability than wild-type PtIDH2. This study expands the phylogeny of the IDH family and provides new insights into the evolution of IDHs.
Collapse
Affiliation(s)
- Shiping Huang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, College of Life Sciences, Anhui Normal University, Wuhu, China.,College of Biological and Food Engineering, Anhui Polytechnic University, Wuhu, China
| | - Jiaxin Zhao
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Wenjing Li
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Peng Wang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Zhenglian Xue
- College of Biological and Food Engineering, Anhui Polytechnic University, Wuhu, China
| | - Guoping Zhu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, Key Laboratory of Biomedicine in Gene Diseases and Health of Anhui Higher Education Institutes, College of Life Sciences, Anhui Normal University, Wuhu, China
| |
Collapse
|
5
|
Tang W, Dong X, Meng J, Feng Y, Xie M, Xu H, Song P. Biochemical characterization and redesign of the coenzyme specificity of a novel monofunctional NAD +-dependent homoserine dehydrogenase from the human pathogen Neisseria gonorrhoeae. Protein Expr Purif 2021; 186:105909. [PMID: 34022392 DOI: 10.1016/j.pep.2021.105909] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/13/2021] [Accepted: 05/15/2021] [Indexed: 12/17/2022]
Abstract
Gonorrhoea, caused by Neisseria gonorrhoeae, is a major global public health concern. Homoserine dehydrogenase (HSD), a key enzyme in the aspartate pathway, is a promising metabolic target against pathogenic infections. In this study, a monofunctional HSD from N. gonorrhoeae (NgHSD) was overexpressed in Escherichia coli and purified to >95% homogeneity for biochemical characterization. Unlike the classic dimeric structure, the purified recombinant NgHSD exists as a tetramer in solution. We determined the enzymatic activity of recombinant NgHSD for l-homoserine oxidation, which revealed that this enzyme was NAD+ dependent, with an approximate 479-fold (kcat/Km) preference for NAD+ over NADP+, and that optimal activity for l-homoserine oxidation occurred at pH 10.5 and 40 °C. At 800 mM, neither NaCl nor KCl increased the activity of NgHSD, in contrast to the behavior of several reported NAD+-independent homologs. Moreover, threonine did not markedly inhibit the oxidation activity of NgHSD. To gain insight into the cofactor specificity, site-directed mutagenesis was used to alter coenzyme specificity. The double mutant L45R/S46R, showing the highest affinity for NADP+, caused a shift in coenzyme preference from NAD+ to NADP+ by a factor of ~974, with a catalytic efficiency comparable with naturally occurring NAD+-independent homologs. Collectively, our results should allow the exploration of drugs targeting NgHSD to treat gonococcal infections and contribute to the prediction of the coenzyme specificity of novel HSDs.
Collapse
Affiliation(s)
- Wanggang Tang
- Department of Biochemistry and Molecular Biology, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China.
| | - Xue Dong
- Research Center of Laboratory Medicine, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Jiang Meng
- Research Center of Laboratory Medicine, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Yanan Feng
- Research Center of Laboratory Medicine, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Manman Xie
- Research Center of Laboratory Medicine, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Haonan Xu
- Research Center of Laboratory Medicine, School of Laboratory Medicine, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Ping Song
- College of Biological and Food Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, China.
| |
Collapse
|