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Nigo F, Nakagawa R, Hirai Y, Imai L, Suzuki Y, Furuta K, Kaito C. Staphylococcus aureus MazG hydrolyzes oxidized guanine nucleotides and contributes to oxidative stress resistance. Biochimie 2023; 209:52-60. [PMID: 36746255 DOI: 10.1016/j.biochi.2023.02.001] [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: 11/23/2022] [Revised: 01/23/2023] [Accepted: 02/02/2023] [Indexed: 02/05/2023]
Abstract
We previously reported that knockout of the mazG (SA1292) gene decreases Staphylococcus aureus killing activity against silkworms. S. aureus MazG (SaMazG) has a nucleotide pyrophosphatase domain conserved among MazG family proteins, but its biochemical characteristics are unknown. In the present study, we purified recombinant N-terminal His-tagged SaMazG protein and examined its biochemical activity. SaMazG hydrolyzed GTP, UTP, dGTP, and TTP into nucleoside monophosphates. Hydrolytic activity of SaMazG against ATP, CTP, dATP, and dCTP was low or not detected. SaMazG exhibited high hydrolytic activity against 8-oxo-GTP and 8-oxo-dGTP, oxidized guanine nucleotides, with a Vmax/Km ratio more than 15-fold that of GTP. Furthermore, the S. aureus mazG knockout mutant was sensitive to hydrogen peroxide compared with the parent strain. These results suggest that SaMazG is a nucleotide pyrophosphatase hydrolyzing oxidized guanine nucleotides that contributes to the oxidative stress resistance of S. aureus.
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Affiliation(s)
- Fuki Nigo
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan.
| | - Ryosuke Nakagawa
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan.
| | - Yuuki Hirai
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
| | - Lina Imai
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan.
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan.
| | - Kazuyuki Furuta
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan.
| | - Chikara Kaito
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Kita-ku, Okayama, Japan.
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Wang S, Gao B, Chen A, Zhang Z, Wang S, Lv L, Zhao G, Li J. Structural analysis of the housecleaning nucleoside triphosphate pyrophosphohydrolase MazG from Mycobacterium tuberculosis. Front Microbiol 2023; 14:1137279. [PMID: 36937295 PMCID: PMC10014863 DOI: 10.3389/fmicb.2023.1137279] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 02/10/2023] [Indexed: 03/05/2023] Open
Abstract
The housecleaning enzyme of Mycobacterium tuberculosis (Mtb), MazG, is a nucleoside triphosphate pyrophosphohydrolase (NTP-PPase) and can hydrolyze all canonical or non-canonical NTPs into NMPs and pyrophosphate. The Mycobacterium tuberculosis MazG (Mtb-MazG) contributes to antibiotic resistance in response to oxidative or nitrosative stress under dormancy, making it a promising target for treating TB in latent infection patients. However, the structural basis of Mtb-MazG is not clear. Here we describe the crystal structure of Mtb-MazG (1-185) at 2.7 Å resolution, composed of two similar folded spherical domains in tandem. Unlike other all-α NTP pyrophosphatases, Mtb-MazG has an N-terminal extra region composed of three α-helices and five β-strands. The second domain is global, with five α-helices located in the N-terminal domain. Gel-filtration assay and SAXS analysis show that Mtb-MazG forms an enzyme-active dimer in solution. In addition, the metal ion Mg2+ is bound with four negative-charged residues Glu119, Glu122, Glu138, and Asp141. Different truncations and site-directed mutagenesis revealed that the full-length dimeric form and the metal ion Mg2+ are indispensable for the catalytic activity of Mtb-MazG. Thus, our work provides new insights into understanding the molecular basis of Mtb-MazG.
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Affiliation(s)
- Sen Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
| | - Baocai Gao
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
| | - Anke Chen
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
| | - Zhifei Zhang
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
| | - Sheng Wang
- Shanghai Zelixir Biotech Company Ltd., Shanghai, China
| | - Liangdong Lv
- School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Guoping Zhao
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
- Guoping Zhao,
| | - Jixi Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Huashan Hospital, MOE Engineering Research Center of Gene Technology, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
- *Correspondence: Jixi Li,
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Scaletti E, Claesson M, Helleday T, Jemth AS, Stenmark P. The First Structure of an Active Mammalian dCTPase and its Complexes With Substrate Analogs and Products. J Mol Biol 2020; 432:1126-1142. [PMID: 31954130 DOI: 10.1016/j.jmb.2020.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/30/2019] [Accepted: 01/03/2020] [Indexed: 11/26/2022]
Abstract
Precise regulation of dNTPs within the cellular nucleotide pool is essential for high accuracy of DNA replication and is critical for retaining the genomic integrity. Recently, human dCTPase (deoxycytidine triphosphatase), also known as DCTPP1 (human all-alpha dCTP pyrophosphatase 1), has been revealed to be a key player in the balance of pyrimidine nucleotide concentrations within cells, with DCTPP1 deficiency causing DNA damage and genetic instability in both chromosomal and mitochondrial DNA. DCTPP1 also exhibits an additional "house cleaning" function as it has been shown to be highly active against modified cytidine triphosphates, such as 5-methyl-dCTP, which, if incorrectly incorporated into DNA can introduce undesirable epigenetic marking. To date, structural studies of mammalian dCTPase have been limited to inactive constructs, which do not provide information regarding the catalytic mechanism of this important enzyme. We present here the first structures of an active mammalian dCTPase from M. musculus in complex with the nonhydrolyzable substrate analog dCMPNPP and the products 5-Me-dCMP and dCMP. These structures provide clear insights into substrate binding and catalysis and clearly elucidate why previous structures of mammalian dCTPase were catalytically inactive. The overall structure of M. musculus dCTPase is highly similar to enzymes from the all-alpha NTP phosphohydrolase superfamily. Comparison of M. musculus dCTPase with homologs from a diverse range of mammals, including humans, shows that the residues, which contribute to substrate recognition, are entirely conserved, further supporting the importance of this enzyme in the protection of genomic integrity in mammalian cells.
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Affiliation(s)
- Emma Scaletti
- Department of Experimental Medical Science, Lund University, Lund, 221 00, Sweden; Department of Biochemistry and Biophysics, Stockholm University, Stockholm, S-106 91, Sweden
| | - Magnus Claesson
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, S-106 91, Sweden
| | - Thomas Helleday
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, Stockholm, S-171 76, Sweden; Sheffield Cancer Centre, Department of Oncology and Metabolism, University of Sheffield, Sheffield, S10 2RX, UK
| | - Ann-Sofie Jemth
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, Stockholm, S-171 76, Sweden.
| | - Pål Stenmark
- Department of Experimental Medical Science, Lund University, Lund, 221 00, Sweden; Department of Biochemistry and Biophysics, Stockholm University, Stockholm, S-106 91, Sweden.
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