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Liu J, Yuan R, Shao W, Wang J, Silman I, Sussman JL. Do "Newly Born" orphan proteins resemble "Never Born" proteins? A study using three deep learning algorithms. Proteins 2023. [PMID: 37092778 DOI: 10.1002/prot.26496] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 02/26/2023] [Accepted: 04/01/2023] [Indexed: 04/25/2023]
Abstract
"Newly Born" proteins, devoid of detectable homology to any other proteins, known as orphan proteins, occur in a single species or within a taxonomically restricted gene family. They are generated by the expression of novel open reading frames, and appear throughout evolution. We were curious if three recently developed programs for predicting protein structures, namely, AlphaFold2, RoseTTAFold, and ESMFold, might be of value for comparison of such "Newly Born" proteins to random polypeptides with amino acid content similar to that of native proteins, which have been called "Never Born" proteins. The programs were used to compare the structures of two sets of "Never Born" proteins that had been expressed-Group 1, which had been shown experimentally to possess substantial secondary structure, and Group 3, which had been shown to be intrinsically disordered. Overall, although the models generated were scored as being of low quality, they nevertheless revealed some general principles. Specifically, all four members of Group 1 were predicted to be compact by all three algorithms, in agreement with the experimental data, whereas the members of Group 3 were predicted to be very extended, as would be expected for intrinsically disordered proteins, again consistent with the experimental data. These predicted differences were shown to be statistically significant by comparing their accessible surface areas. The three programs were then used to predict the structures of three orphan proteins whose crystal structures had been solved, two of which display novel folds. Surprisingly, only for the protein which did not have a novel fold, and was taxonomically restricted, rather than being a true orphan, did all three algorithms predict very similar, high-quality structures, closely resembling the crystal structure. Finally, they were used to predict the structures of seven orphan proteins with well-identified biological functions, whose 3D structures are not known. Two proteins, which were predicted to be disordered based on their sequences, are predicted by all three structure algorithms to be extended structures. The other five were predicted to be compact structures with only two exceptions in the case of AlphaFold2. All three prediction algorithms make remarkably similar and high-quality predictions for one large protein, HCO_11565, from a nematode. It is conjectured that this is due to many homologs in the taxonomically restricted family of which it is a member, and to the fact that the Dali server revealed several nonrelated proteins with similar folds. An animated Interactive 3D Complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:Proteins:3.
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Affiliation(s)
- Jing Liu
- Department of Biotechnology and Food Engineering, Guangdong Technion-Israel Institute of Technology, Shantou, China
- Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Rongqing Yuan
- Department of Chemistry, Tsinghua University, Beijing, China
| | - Wei Shao
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jitong Wang
- Department of Chemistry, Tsinghua University, Beijing, China
| | - Israel Silman
- Department of Brain Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Joel L Sussman
- Department of Chemical and Structural Biology, The Weizmann Institute of Science, Rehovot, Israel
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2
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Leng Y, Zhou H, Wang W, Fu J. Diagnostic role of urinary CA-2 in urinary stones and its prediction of complications. Am J Transl Res 2022; 14:8686-8694. [PMID: 36628213 PMCID: PMC9827313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 11/21/2022] [Indexed: 01/12/2023]
Abstract
BACKGROUND Carbonic anhydrase-2 (CA-2) is involved in the mineralization and calcification of organisms. Evidence suggests that CA-2 is associated with urolithiasis. However, the relationship between CA-2 and urinary stones remains unclear. The study aimed to assess the correlation of urinary CA-2 (uCA-2) level with the risk of urinary stones. METHODS A retrospective cohort study was conducted on patients with urinary stones and healthy subjects who presented to our hospital between March 2017 and November 2019 to determine the pretreatment uCA-2 level by enzyme linked immunosorbent assay (ELISA). Differences in uCA-2 levels between patients with urinary stones and healthy subjects were compared. Then, comparison between stone patients with complications and those without was carried out as well as correlation analysis to detect factors associated with biomarker expression. RESULTS Patients with urinary stones (n=118) were designated the urinary stones group and healthy subjects (n=42) were designated the healthy control group. The mean pretreatment uCA-2 level was significantly higher in cases than in controls (P=0.028). Furthermore, the uCA-2 level had a positive correlation with urinary stone-associated complications (R=0.379, P<0.001), especially pain (R=0.524, P<0.001) and hematuria (R=0.374, P<0.001). Receiver operating characteristic curve (ROC) analysis revealed that a uCA-2 level threshold of 10.94 ng/mL had 83.67% sensitivity and 68.12% specificity for predicting complications in patients with urinary stones. CONCLUSION Excessive uCA-2 excretion is a major risk factor for urinary stones. Our findings suggest that uCA-2 may be used as a novel biomarker for the diagnosis of urinary stones and the prediction of its complications.
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Affiliation(s)
- Yuanjing Leng
- Department of Urology, Affiliated Hospital of Jiujiang CollegeJiujiang 332000, Jiangxi, People’s Republic of China
| | - Haibin Zhou
- Department of Urology, Affiliated Hospital of Jiujiang CollegeJiujiang 332000, Jiangxi, People’s Republic of China
| | - Wenjuan Wang
- Department of Clinical Laboratory, Affiliated Hospital of Jiujiang CollegeJiujiang 332000, Jiangxi, People’s Republic of China
| | - Jiangling Fu
- Clinical Precision Medical Research Center, Affiliated Hospital of Jiujiang CollegeJiujiang 332000, Jiangxi, People’s Republic of China
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3
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Chand K, Chu YC, Wang TW, Kao CL, Lin YF, Tsai ML, Hsu SC. Nitric oxide generation study of unsymmetrical β-diketiminato copper(II) nitrite complexes. Dalton Trans 2022; 51:3485-3496. [DOI: 10.1039/d1dt03711k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The β-diketiminato copper(II) L1CuCl−L4CuCl and their nitrite complexes L1Cu(O2N) and L2Cu(O2N) has been synthesized and characterized. The X-ray structure of the L1CuCl−L4CuCl complexes clearly indicates towards the mononuclear structure with...
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4
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Nocentini A, Angeli A, Carta F, Winum JY, Zalubovskis R, Carradori S, Capasso C, Donald WA, Supuran CT. Reconsidering anion inhibitors in the general context of drug design studies of modulators of activity of the classical enzyme carbonic anhydrase. J Enzyme Inhib Med Chem 2021; 36:561-580. [PMID: 33615947 PMCID: PMC7901698 DOI: 10.1080/14756366.2021.1882453] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Inorganic anions inhibit the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) generally by coordinating to the active site metal ion. Cyanate was reported as a non-coordinating CA inhibitor but those erroneous results were subsequently corrected by another group. We review the anion CA inhibitors (CAIs) in the more general context of drug design studies and the discovery of a large number of inhibitor classes and inhibition mechanisms, including zinc binders (sulphonamides and isosteres, dithiocabamates and isosteres, thiols, selenols, benzoxaboroles, ninhydrins, etc.); inhibitors anchoring to the zinc-coordinated water molecule (phenols, polyamines, sulfocoumarins, thioxocoumarins, catechols); CAIs occluding the entrance to the active site (coumarins and derivatives, lacosamide), as well as compounds that bind outside the active site. All these new chemotypes integrated with a general procedure for obtaining isoform-selective compounds (the tail approach) has resulted, through the guidance of rigorous X-ray crystallography experiments, in the development of highly selective CAIs for all human CA isoforms with many pharmacological applications.
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Affiliation(s)
- Alessio Nocentini
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Florence, Italy
| | - Andrea Angeli
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Florence, Italy
| | - Fabrizio Carta
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Florence, Italy
| | | | - Raivis Zalubovskis
- Latvian Institute of Organic Synthesis, Riga, Latvia.,Institute of Technology of Organic Chemistry, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Riga, Latvia
| | - Simone Carradori
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Clemente Capasso
- Institute of Biosciences and Bioresources, National Research Council, Napoli, Italy
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, Australia
| | - Claudiu T Supuran
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Florence, Italy
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5
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Stauffer M, Sakhaei Z, Greene C, Ghosh P, Bertke JA, Warren TH. Mechanism of O-Atom Transfer from Nitrite: Nitric Oxide Release at Copper(II). Inorg Chem 2021; 60:15968-15974. [PMID: 34184870 DOI: 10.1021/acs.inorgchem.1c00625] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nitric oxide (NO) is a key signaling molecule in health and disease. While nitrite acts as a reservoir of NO activity, mechanisms for NO release require further understanding. A series of electronically varied β-diketiminatocopper(II) nitrite complexes [CuII](κ2-O2N) react with a range of electronically tuned triarylphosphines PArZ3 that release NO with the formation of O═PArZ3. Second-order rate constants are largest for electron-poor copper(II) nitrite and electron-rich phosphine pairs. Computational analysis reveals a transition-state structure energetically matched with experimentally determined activation barriers. The production of NO follows a pathway that involves nitrite isomerization at CuII from κ2-O2N to κ1-NO2 followed by O-atom transfer (OAT) to form O═PArZ3 and [CuI]-NO that releases NO upon PArZ3 binding at CuI to form [CuI]-PArZ3. These findings illustrate important mechanistic considerations involved in NO formation from nitrite via OAT.
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Affiliation(s)
- Molly Stauffer
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Zeinab Sakhaei
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Christine Greene
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Pokhraj Ghosh
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
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6
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Tsikas D, Gambaryan S. Nitrous anhydrase activity of carbonic anhydrase II: cysteine is required for nitric oxide (NO) dependent phosphorylation of VASP in human platelets. J Enzyme Inhib Med Chem 2021; 36:525-534. [PMID: 33508993 PMCID: PMC7875556 DOI: 10.1080/14756366.2021.1874946] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The carbonic anhydrase (CA) family does not only catalyse the reversible hydration of CO2 to bicarbonate, but it also possesses esterase and phosphatase activity. Recently, bovine CA II and human CA II have been reported to convert inorganic nitrite (O=N-O−) to nitric oxide (NO) and nitrous anhydride (N2O3). Given the ability of NO to mediate vasodilation and inhibit platelet aggregation, this CA II activity would represent a bioactivation of nitrite. There are contradictory reports in the literature and the physiological role of CA II nitrite bioactivation is still disputed. Here, we provide new experimental data in support of the nitrous anhydrase activity of CA II and the key role L-cysteine in the bioactivation of nitrite by CA II. Using washed human platelets and by measuring VASP phosphorylation we provide evidence that exogenous nitrite (10 µM) is bioactivated to NO in a manner strongly depending on L-cysteine (100 and 200 µM). The process is not inhibitable by acetazolamide, a potent CA inhibitor. The contradictory results of recently published studies in this area are thoroughly discussed.
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Affiliation(s)
- Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Hannover, Germany
| | - Stepan Gambaryan
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Petersburg, Russia
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7
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Tsikas D. Comment on the article Structure and mechanism of copper-carbonic anhydrase II: a nitrite reductase. IUCRJ 2021; 8:327-328. [PMID: 33708408 PMCID: PMC7924222 DOI: 10.1107/s2052252520016644] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 12/23/2020] [Indexed: 05/15/2023]
Abstract
The paper discusses a recent paper [Andring et al. (2020). IUCrJ, 7, 287-293] on the nitrite reductase and nitrous anhydrase activity of carbonic anhydrase.
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Affiliation(s)
- Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Carl-Neuberg-Str. 1, Hannover, 30625, Germany
- Correspondence e-mail:
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8
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Andring JT, Kim CU, McKenna R. Erratum: Structure and mechanism of copper-carbonic anhydrase II: a nitrite reductase. Corrigendum. IUCRJ 2021; 8:329. [PMID: 33708409 PMCID: PMC7924238 DOI: 10.1107/s2052252521000208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
[This corrects the article DOI: 10.1107/S2052252520000986.].
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Affiliation(s)
- Jacob T. Andring
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610 USA
| | - Chae Un Kim
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610 USA
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9
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The Active Site of a Prototypical “Rigid” Drug Target is Marked by Extensive Conformational Dynamics. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Deshmukh SS, Kálmán L. Tuning the redox potential of the primary electron donor in bacterial reaction centers by manganese binding and light-induced structural changes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148285. [PMID: 32777306 DOI: 10.1016/j.bbabio.2020.148285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/02/2020] [Accepted: 08/04/2020] [Indexed: 11/26/2022]
Abstract
The influence of transition metal binding on the charge storage ability of native bacterial reaction centers (BRCs) was investigated. Binding of manganous ions uniquely prevented the light-induced conformational changes that would yield to long lifetimes of the charge separated state and the drop of the redox potential of the primary electron donor (P). The lifetimes of the stable charge pair in the terminal conformations were shortened by 50-fold and 7-fold upon manganous and cupric ion binding, respectively. Nickel and zinc binding had only marginal effects. Binding of manganese not only prevented the drop of the potential of P/P+ but also elevated it by up to 117 mV depending on where the metal was binding. With variable conditions, facilitating either manganese binding or light-induced structural changes a controlled tuning of the potential of P/P+ in multiple steps was demonstrated in a range of ~200 mV without the need of a mutation or synthesis. Under the selected conditions, manganese binding was achieved without its photochemical oxidation thus, the energized but still native BRCs can be utilized in photochemistry that is not reachable with regular BRCs. A 42 Å long hydrophobic tunnel was identified that became obstructed upon manganese binding and its likely role is to deliver protons from the hydrophobic core to the surface during conformational changes.
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Affiliation(s)
| | - László Kálmán
- Department of Physics, Concordia University, Montreal, QC, Canada.
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11
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Singh H, Das CK, Vasa SK, Grohe K, Schäfer LV, Linser R. The Active Site of a Prototypical "Rigid" Drug Target is Marked by Extensive Conformational Dynamics. Angew Chem Int Ed Engl 2020; 59:22916-22921. [PMID: 32965765 PMCID: PMC7756556 DOI: 10.1002/anie.202009348] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/16/2020] [Indexed: 12/23/2022]
Abstract
Drug discovery, in particular optimization of candidates using medicinal chemistry, is generally guided by structural biology. However, for optimizing binding kinetics, relevant for efficacy and off-target effects, information on protein motion is important. Herein, we demonstrate for the prototypical textbook example of an allegedly "rigid protein" that substantial active-site dynamics have generally remained unrecognized, despite thousands of medicinal-chemistry studies on this model over decades. Comparing cryogenic X-ray structures, solid-state NMR on micro-crystalline protein at room temperature, and solution NMR structure and dynamics, supported by MD simulations, we show that under physiologically relevant conditions the pocket is in fact shaped by pronounced open/close conformational-exchange dynamics. The study, which is of general significance for pharmacological research, evinces a generic pitfall in drug discovery routines.
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Affiliation(s)
- Himanshu Singh
- Faculty of Chemistry and Chemical Biology, Technical University Dortmund, Otto-Hahn-Str. 4a, 44227, Dortmund, Germany.,Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Chandan K Das
- Theoretical Chemistry, Ruhr University Bochum, Universitätsstr. 150, 44801, Bochum, Germany
| | - Suresh K Vasa
- Faculty of Chemistry and Chemical Biology, Technical University Dortmund, Otto-Hahn-Str. 4a, 44227, Dortmund, Germany.,Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Kristof Grohe
- Faculty of Chemistry and Chemical Biology, Technical University Dortmund, Otto-Hahn-Str. 4a, 44227, Dortmund, Germany.,Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Lars V Schäfer
- Theoretical Chemistry, Ruhr University Bochum, Universitätsstr. 150, 44801, Bochum, Germany
| | - Rasmus Linser
- Faculty of Chemistry and Chemical Biology, Technical University Dortmund, Otto-Hahn-Str. 4a, 44227, Dortmund, Germany.,Faculty for Chemistry and Pharmacy, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, 81377, Munich, Germany
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12
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Kim JK, Lee C, Lim SW, Adhikari A, Andring JT, McKenna R, Ghim CM, Kim CU. Elucidating the role of metal ions in carbonic anhydrase catalysis. Nat Commun 2020; 11:4557. [PMID: 32917908 PMCID: PMC7486293 DOI: 10.1038/s41467-020-18425-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/20/2020] [Indexed: 01/07/2023] Open
Abstract
Why metalloenzymes often show dramatic changes in their catalytic activity when subjected to chemically similar but non-native metal substitutions is a long-standing puzzle. Here, we report on the catalytic roles of metal ions in a model metalloenzyme system, human carbonic anhydrase II (CA II). Through a comparative study on the intermediate states of the zinc-bound native CA II and non-native metal-substituted CA IIs, we demonstrate that the characteristic metal ion coordination geometries (tetrahedral for Zn2+, tetrahedral to octahedral conversion for Co2+, octahedral for Ni2+, and trigonal bipyramidal for Cu2+) directly modulate the catalytic efficacy. In addition, we reveal that the metal ions have a long-range (~10 Å) electrostatic effect on restructuring water network in the active site. Our study provides evidence that the metal ions in metalloenzymes have a crucial impact on the catalytic mechanism beyond their primary chemical properties.
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Affiliation(s)
- Jin Kyun Kim
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
| | - Cheol Lee
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
| | - Seon Woo Lim
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
| | - Aniruddha Adhikari
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
| | - Jacob T. Andring
- grid.15276.370000 0004 1936 8091Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610 USA
| | - Robert McKenna
- grid.15276.370000 0004 1936 8091Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610 USA
| | - Cheol-Min Ghim
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
| | - Chae Un Kim
- grid.42687.3f0000 0004 0381 814XDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Republic of Korea
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13
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Abstract
Metalloenzymes such as the carbonic anhydrases (CAs, EC 4.2.1.1) possess highly specialized active sites that promote fast reaction rates and high substrate selectivity for the physiologic reaction that they catalyze, hydration of CO2 to bicarbonate and a proton. Among the eight genetic CA macrofamilies, α-CAs possess rather spacious active sites and show catalytic promiscuity, being esterases with many types of esters, but also acting on diverse small molecules such as cyanamide, carbonyl sulfide (COS), CS2, etc. Although artificial CAs have been developed with the intent to efficiently catalyse non-biologically related chemical transformations with high control of stereoselectivity, the activities of these enzymes were much lower when compared to natural CAs. Here, we report an overview on the catalytic activities of α-CAs as well as of enzymes which were mutated or artificially designed by incorporation of transition metal ions. In particular, the distinct catalytic mechanisms of the reductase, oxidase and metatheses-ase such as de novo designed CAs are discussed.
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14
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Jonsson BH, Liljas A. Perspectives on the Classical Enzyme Carbonic Anhydrase and the Search for Inhibitors. Biophys J 2020; 119:1275-1280. [PMID: 32910900 DOI: 10.1016/j.bpj.2020.08.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/13/2020] [Accepted: 08/20/2020] [Indexed: 01/19/2023] Open
Abstract
Carbonic anhydrase (CA) is a thoroughly studied enzyme. Its primary role is the rapid interconversion of carbon dioxide and bicarbonate in the cells, where carbon dioxide is produced, and in the lungs, where it is released from the blood. At the same time, it regulates pH homeostasis. The inhibitory function of sulfonamides on CA was discovered some 80 years ago. There are numerous physiological-therapeutic conditions in which inhibitors of carbonic anhydrase have a positive effect, such as glaucoma, or act as diuretics. With the realization that several isoenzymes of carbonic anhydrase are associated with the development of several types of cancer, such as brain and breast cancer, the development of inhibitor drugs specific to those enzyme forms has exploded. We would like to highlight the breadth of research on the enzyme as well as draw the attention to some problems in recent published work on inhibitor discovery.
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Affiliation(s)
- Bengt-Harald Jonsson
- Department of Physics, Chemistry, and Biology, Division of Chemistry, Linköping University, Linköping, Sweden
| | - Anders Liljas
- Departments of Biochemistry and Structural Biology, Lund University, Lund, Sweden.
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15
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Abstract
The enzyme carbonic anhydrase binds its zinc ion by three histidine residues in a similar manner to the way copper is bound to nitrite reductase. This remote similarity has now been shown to be real [Andring et al. (2020). IUCrJ, 7, 287-293]. A carbonic anhydrase with two bound copper ions is also a nitrite reductase.
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Affiliation(s)
- Anders Liljas
- Biochemistry and Structural Biology, Lund University, Lund, Sweden
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