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Suthi S, Mounika A, Potukuchi VGKS. Elevated acetate kinase (ackA) gene expression, activity, and biofilm formation observed in methicillin-resistant strains of Staphylococcus aureus (MRSA). J Genet Eng Biotechnol 2023; 21:100. [PMID: 37831271 PMCID: PMC10575836 DOI: 10.1186/s43141-023-00555-0] [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: 10/21/2022] [Accepted: 09/20/2023] [Indexed: 10/14/2023]
Abstract
BACKGROUND Staphylococcus aureus spreads its infections through biofilms. This usually happens in the stationary phase of S. aureus growth where it utilizes accumulated acetate as a carbon source via the phosphotrans-acetylase-acetate kinase (Pta-Ack) pathway. In which acetate kinase (ackA) catalyzes the substrate-level phosphorylation, a vital secondary energy-yielding pathway that promotes biofilms formation aids bacterium survival in hostile environments. In this study, we describe the cloning, sequencing, and expression of S. aureus ackA gene. The expression analysis of ackA gene in methicillin-resistant strains of S. aureus (MRSA) correlates with ackA activity and biofilm units. The uniqueness of ackA was analyzed by using in silico methods. RESULTS Elevated ackA gene expression was observed in MRSA strains, which correlates with increased ackA activity and biofilm units, explaining ackA role in MRSA growth and pathogenicity. The pure recombinant acetate kinase showed a molecular weight of 44 kDa, with enzyme activity of 3.35 ± 0.05 μM/ml/min. The presence of ACKA-1, ACKA-2 sites, one ATP, and five serine/threonine-protein kinase sites in the ackA gene (KC954623.1) indicated that acetyl phosphate production is strongly controlled. The comparative structural analysis of S. aureus ackA with ackA structures of Mycobacterium avium (3P4I) and Salmonella typhimurium (3SLC) exhibited variations as indicated by the RMSD values 1.877 Å and 2.141 Å respectively, explaining why ackA functions are differently placed in bacteria, concurring its involvement in S. aureus pathogenesis. CONCLUSIONS Overall findings of this study highlight the correlation of ackA expression profoundly increases survival capacity through biofilm formation, which is a pathogenic factor in MRSA and plays a pivotal role in infection spreading.
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Affiliation(s)
- Subbarayudu Suthi
- Microbial Genetics Laboratory, Department of Biotechnology, Sri Venkateswara Institute of Medical Sciences, Alipiri Road, Tirupati, 517501, Andhra Pradesh, India
| | - A Mounika
- Microbial Genetics Laboratory, Department of Biotechnology, Sri Venkateswara Institute of Medical Sciences, Alipiri Road, Tirupati, 517501, Andhra Pradesh, India
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2
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Nattermann M, Wenk S, Pfister P, He H, Lee SH, Szymanski W, Guntermann N, Zhu F, Nickel L, Wallner C, Zarzycki J, Paczia N, Gaißert N, Franciò G, Leitner W, Gonzalez R, Erb TJ. Engineering a new-to-nature cascade for phosphate-dependent formate to formaldehyde conversion in vitro and in vivo. Nat Commun 2023; 14:2682. [PMID: 37160875 PMCID: PMC10170137 DOI: 10.1038/s41467-023-38072-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 04/14/2023] [Indexed: 05/11/2023] Open
Abstract
Formate can be envisioned at the core of a carbon-neutral bioeconomy, where it is produced from CO2 by (electro-)chemical means and converted into value-added products by enzymatic cascades or engineered microbes. A key step in expanding synthetic formate assimilation is its thermodynamically challenging reduction to formaldehyde. Here, we develop a two-enzyme route in which formate is activated to formyl phosphate and subsequently reduced to formaldehyde. Exploiting the promiscuity of acetate kinase and N-acetyl-γ-glutamyl phosphate reductase, we demonstrate this phosphate (Pi)-based route in vitro and in vivo. We further engineer a formyl phosphate reductase variant with improved formyl phosphate conversion in vivo by suppressing cross-talk with native metabolism and interface the Pi route with a recently developed formaldehyde assimilation pathway to enable C2 compound formation from formate as the sole carbon source in Escherichia coli. The Pi route therefore offers a potent tool in expanding the landscape of synthetic formate assimilation.
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Affiliation(s)
- Maren Nattermann
- Department of Biochemistry & Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Sebastian Wenk
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Pascal Pfister
- Department of Biochemistry & Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Hai He
- Department of Biochemistry & Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Seung Hwan Lee
- Department of Chemical, Biological, and Materials Engineering, University of South Florida, Tampa, FL, USA
| | - Witold Szymanski
- Institute of Translational Proteomics, Philipps University, Marburg, Germany
| | - Nils Guntermann
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen, Germany
| | - Fayin Zhu
- Department of Chemical, Biological, and Materials Engineering, University of South Florida, Tampa, FL, USA
| | | | | | - Jan Zarzycki
- Department of Biochemistry & Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Nicole Paczia
- Core Facility for Metabolomics and Small Molecule Mass Spectrometry, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | | | - Giancarlo Franciò
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen, Germany
| | - Walter Leitner
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen, Germany
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Ramon Gonzalez
- Department of Chemical, Biological, and Materials Engineering, University of South Florida, Tampa, FL, USA
| | - Tobias J Erb
- Department of Biochemistry & Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany.
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3
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McDowell JR, Bai G, Lasek-Nesselquist E, Eisele LE, Wu Y, Hurteau G, Johnson R, Bai Y, Chen Y, Chan J, McDonough KA. Mycobacterial phosphodiesterase Rv0805 is a virulence determinant and its cyclic nucleotide hydrolytic activity is required for propionate detoxification. Mol Microbiol 2023; 119:401-422. [PMID: 36760076 PMCID: PMC10315211 DOI: 10.1111/mmi.15030] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 01/15/2023] [Accepted: 01/21/2023] [Indexed: 02/11/2023]
Abstract
Cyclic AMP (cAMP) signaling is essential to Mycobacterium tuberculosis (Mtb) pathogenesis. However, the roles of phosphodiesterases (PDEs) Rv0805, and the recently identified Rv1339, in cAMP homeostasis and Mtb biology are unclear. We found that Rv0805 modulates Mtb growth within mice, macrophages and on host-associated carbon sources. Mycobacterium bovis BCG grown on a combination of propionate and glycerol as carbon sources showed high levels of cAMP and had a strict requirement for Rv0805 cNMP hydrolytic activity. Supplementation with vitamin B12 or spontaneous genetic mutations in the pta-ackA operon restored the growth of BCGΔRv0805 and eliminated propionate-associated cAMP increases. Surprisingly, reduction of total cAMP levels by ectopic expression of Rv1339 restored only 20% of growth, while Rv0805 complementation fully restored growth despite a smaller effect on total cAMP levels. Deletion of an Rv0805 localization domain also reduced BCG growth in the presence of propionate and glycerol. We propose that localized Rv0805 cAMP hydrolysis modulates activity of a specialized pathway associated with propionate metabolism, while Rv1339 has a broader role in cAMP homeostasis. Future studies will address the biological roles of Rv0805 and Rv1339, including their impacts on metabolism, cAMP signaling and Mtb pathogenesis.
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Affiliation(s)
- James R. McDowell
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Guangchun Bai
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Immunology and Microbial Disease, MC-151, Albany Medical College, Albany, NY 12208-3479
| | - Erica Lasek-Nesselquist
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Leslie E. Eisele
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Yan Wu
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Gregory Hurteau
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Richard Johnson
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Yinlan Bai
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Yong Chen
- Albert Einstein College of Medicine, Bronx, NY
| | - John Chan
- Albert Einstein College of Medicine, Bronx, NY
| | - Kathleen A. McDonough
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
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4
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Huang R, Liu H, Zhao W, Wang S, Wang S, Cai J, Yang C. AdpA, a developmental regulator, promotes ε-poly-l-lysine biosynthesis in Streptomyces albulus. Microb Cell Fact 2022; 21:60. [PMID: 35397580 PMCID: PMC8994273 DOI: 10.1186/s12934-022-01785-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/31/2022] [Indexed: 12/01/2022] Open
Abstract
Background AdpA is a global regulator of morphological differentiation and secondary metabolism in Streptomyces, but the regulatory roles of the Streptomyces AdpA family on the biosynthesis of the natural product ε-poly-l-lysine (ε-PL) remain unidentified, and few studies have focused on increasing the production of ε-PL by manipulating transcription factors in Streptomyces. Results In this study, we revealed the regulatory roles of different AdpA homologs in ε-PL biosynthesis and morphological differentiation and effectively promoted ε-PL production and sporulation in Streptomycesalbulus NK660 by heterologously expressing adpA from S.neyagawaensis NRRLB-3092 (adpASn). First, we identified a novel AdpA homolog named AdpASa in S.albulus NK660 and characterized its function as an activator of ε-PL biosynthesis and morphological differentiation. Subsequently, four heterologous AdpA homologs were selected to investigate their phylogenetic relationships and regulatory roles in S.albulus, and AdpASn was demonstrated to have the strongest ability to promote both ε-PL production and sporulation among these five AdpA proteins. The ε-PL yield of S.albulus heterologously expressing adpASn was approximately 3.6-fold higher than that of the control strain. Finally, we clarified the mechanism of AdpASn in enhancing ε-PL biosynthesis and its effect on ε-PL polymerization degree using real-time quantitative PCR, microscale thermophoresis and MALDI-TOF–MS. AdpASn was purified, and its seven direct targets, zwf, tal, pyk2, pta, ack, pepc and a transketolase gene (DC74_2409), were identified, suggesting that AdpASn may cause the redistribution of metabolic flux in central metabolism pathways, which subsequently provides more carbon skeletons and ATP for ε-PL biosynthesis in S.albulus. Conclusions Here, we characterized the positive regulatory roles of Streptomyces AdpA homologs in ε-PL biosynthesis and their effects on morphological differentiation and reported for the first time that AdpASn promotes ε-PL biosynthesis by affecting the transcription of its target genes in central metabolism pathways. These findings supply valuable insights into the regulatory roles of the Streptomyces AdpA family on ε-PL biosynthesis and morphological differentiation and suggest that AdpASn may be an effective global regulator for enhanced production of ε-PL and other valuable secondary metabolites in Streptomyces. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01785-6.
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5
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Tao YM, Bu CY, Zou LH, Hu YL, Zheng ZJ, Ouyang J. A comprehensive review on microbial production of 1,2-propanediol: micro-organisms, metabolic pathways, and metabolic engineering. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:216. [PMID: 34794503 PMCID: PMC8600716 DOI: 10.1186/s13068-021-02067-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/07/2021] [Indexed: 06/13/2023]
Abstract
1,2-Propanediol is an important building block as a component used in the manufacture of unsaturated polyester resin, antifreeze, biofuel, nonionic detergent, etc. Commercial production of 1,2-propanediol through microbial biosynthesis is limited by low efficiency, and chemical production of 1,2-propanediol requires petrochemically derived routes involving wasteful power consumption and high pollution emissions. With the development of various strategies based on metabolic engineering, a series of obstacles are expected to be overcome. This review provides an extensive overview of the progress in the microbial production of 1,2-propanediol, particularly the different micro-organisms used for 1,2-propanediol biosynthesis and microbial production pathways. In addition, outstanding challenges associated with microbial biosynthesis and feasible metabolic engineering strategies, as well as perspectives on the future microbial production of 1,2-propanediol, are discussed.
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Affiliation(s)
- Yuan-Ming Tao
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Chong-Yang Bu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Li-Hua Zou
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Yue-Li Hu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Zhao-Juan Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Jia Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, People's Republic of China.
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China.
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6
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Kim Y, Lama S, Agrawal D, Kumar V, Park S. Acetate as a potential feedstock for the production of value-added chemicals: Metabolism and applications. Biotechnol Adv 2021; 49:107736. [PMID: 33781888 DOI: 10.1016/j.biotechadv.2021.107736] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 02/22/2021] [Accepted: 03/19/2021] [Indexed: 10/21/2022]
Abstract
Acetate is regarded as a promising carbon feedstock in biological production owing to its possible derivation from C1 gases such as CO, CO2 and methane. To best use of acetate, comprehensive understanding of acetate metabolisms from genes and enzymes to pathways and regulations is needed. This review aims to provide an overview on the potential of acetate as carbon feedstock for industrial biotechnology. Biochemical, microbial and biotechnological aspects of acetate metabolism are described. Especially, the current state-of-the art in the production of value-added chemicals from acetate is summarized. Challenges and future perspectives are also provided.
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Affiliation(s)
- Yeonhee Kim
- School of Energy and Chemical Engineering, UNIST, 50, UNIST-gil, Ulsan 44919, Republic of Korea
| | - Suman Lama
- School of Energy and Chemical Engineering, UNIST, 50, UNIST-gil, Ulsan 44919, Republic of Korea
| | - Deepti Agrawal
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR- Indian Institute of Petroleum, Mohkampur, Dehradun 248005, India
| | - Vinod Kumar
- Centre for Climate and Environmental Protection, School of Water, Energy and Environment, Cranfield University, Cranfield, MK430AL, United Kingdom.
| | - Sunghoon Park
- School of Energy and Chemical Engineering, UNIST, 50, UNIST-gil, Ulsan 44919, Republic of Korea.
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7
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Sekhar T, Thriveni P, Ramesh K, Giri Prasad P, Srihari I, Gorityala N, Rao Sagurthi S, Sankar Allam U. Green synthesis, antitubercular evaluation, and molecular docking studies of ethyl 3,5-dicyano-6-oxo-2,4-diarylpiperidine-3-carboxylate derivatives. Med Chem Res 2020. [DOI: 10.1007/s00044-020-02519-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Bachochin MJ, Venegas JC, Singh G, Zhang L, Barber RD. Characterization of a butyrate kinase from Desulfovibrio vulgaris str. Hildenborough. FEMS Microbiol Lett 2020; 367:5804727. [PMID: 32166312 DOI: 10.1093/femsle/fnaa047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 03/10/2020] [Indexed: 11/13/2022] Open
Abstract
Short and branched chain fatty acid kinases participate in both bacterial anabolic and catabolic processes, including fermentation, through the reversible, ATP-dependent synthesis of acyl phosphates. This study reports biochemical properties of a predicted butyrate kinase from Desulfovibrio vulgaris str. Hildenborough (DvBuk) expressed heterologously and purified from Escherichia coli. Gel filtration chromatography indicates purified DvBuk is active as a dimer. The optimum temperature and pH for DvBuk activity is 44°C and 7.5, respectively. The enzyme displays enhanced thermal stability in the presence of substrates as observed for similar enzymes. Measurement of kcat and KM for various substrates reveals DvBuk exhibits the highest catalytic efficiencies for butyrate, valerate and isobutyrate. In particular, these measurements reveal this enzyme's apparent high affinity for C4 fatty acids relative to other butyrate kinases. These results have implications on structure and function relationships within the ASKHA superfamily of phosphotransferases, particularly regarding the acyl binding pocket, as well as potential physiological roles for this enzyme in Desulfovibrio vulgaris str. Hildenborough.
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Affiliation(s)
- Maxwell J Bachochin
- Department of Biological Sciences, College of Natural and Health Sciences, University of Wisconsin-Parkside, Room 355 Greenquist Hall; 900 Wood Rd., Kenosha, WI 53141-2000, USA
| | - Jessica Castillo Venegas
- Department of Biological Sciences, College of Natural and Health Sciences, University of Wisconsin-Parkside, Room 355 Greenquist Hall; 900 Wood Rd., Kenosha, WI 53141-2000, USA
| | - Gundeep Singh
- Department of Biological Sciences, College of Natural and Health Sciences, University of Wisconsin-Parkside, Room 355 Greenquist Hall; 900 Wood Rd., Kenosha, WI 53141-2000, USA
| | - Liyang Zhang
- Department of Biological Sciences, College of Natural and Health Sciences, University of Wisconsin-Parkside, Room 355 Greenquist Hall; 900 Wood Rd., Kenosha, WI 53141-2000, USA
| | - Robert D Barber
- Department of Biological Sciences, College of Natural and Health Sciences, University of Wisconsin-Parkside, Room 355 Greenquist Hall; 900 Wood Rd., Kenosha, WI 53141-2000, USA
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9
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Abstract
Acetylation is a posttranslational modification conserved in all domains of life that is carried out by N-acetyltransferases. While acetylation can occur on Nα-amino groups, this review will focus on Nε-acetylation of lysyl residues and how the posttranslational modification changes the cellular physiology of bacteria. Up until the late 1990s, acetylation was studied in eukaryotes in the context of chromatin maintenance and gene expression. At present, bacterial protein acetylation plays a prominent role in central and secondary metabolism, virulence, transcription, and translation. Given the diversity of niches in the microbial world, it is not surprising that the targets of bacterial protein acetyltransferases are very diverse, making their biochemical characterization challenging. The paradigm for acetylation in bacteria involves the acetylation of acetyl-CoA synthetase, whose activity must be tightly regulated to maintain energy charge homeostasis. While this paradigm has provided much mechanistic detail for acetylation and deacetylation, in this review we discuss advances in the field that are changing our understanding of the physiological role of protein acetylation in bacteria.
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Affiliation(s)
- Chelsey M VanDrisse
- Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA;
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10
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Short-Chain Fatty Acids Alter Metabolic and Virulence Attributes of Borrelia burgdorferi. Infect Immun 2018; 86:IAI.00217-18. [PMID: 29891543 DOI: 10.1128/iai.00217-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/06/2018] [Indexed: 12/22/2022] Open
Abstract
Borrelia burgdorferi responds to a variety of host-derived factors and appropriately alters its gene expression for adaptation under different host-specific conditions. We previously showed that various levels of acetate, a short-chain fatty acid (SCFA), altered the protein profile of B. burgdorferi In this study, we determined the effects of other physiologically relevant SCFAs in the regulation of metabolic/virulence-associated proteins using mutant borrelial strains. No apparent increase in the synthesis of outer surface protein C (OspC) was noted when a carbon storage regulator A (csrA of B. burgdorferi, or csrABb ) mutant (mt) was propagated within dialysis membrane chambers implanted within rat peritoneal cavity, while the parental wild type (wt; B31-A3 strain) and csrABb cis-complemented strain (ct) had increased OspC with a reciprocal reduction in OspA levels. Growth rates of wt, mt, ct, 7D (csrABb mutant lacking 7 amino acids at the C terminus), and 8S (csrABb with site-specific changes altering its RNA-binding properties) borrelial strains were similar in the presence of acetate. Increased levels of propionate and butyrate reduced the growth rates of all strains tested, with mt and 8S exhibiting profound growth deficits at higher concentrations of propionate. Transcriptional levels of rpoS and ospC were elevated on supplementation of SCFAs compared to those of untreated spirochetes. Immunoblot analysis revealed elevated levels of RpoS, OspC, and DbpA with increased levels of SCFAs. Physiological levels of SCFAs prevalent in select human and rodent fluids were synergistic with mammalian host temperature and pH to increase the levels of aforementioned proteins, which could impact the colonization of B. burgdorferi during the mammalian phase of infection.
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11
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Majou D, Christieans S. Mechanisms of the bactericidal effects of nitrate and nitrite in cured meats. Meat Sci 2018; 145:273-284. [PMID: 30005374 DOI: 10.1016/j.meatsci.2018.06.013] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 06/12/2018] [Accepted: 06/12/2018] [Indexed: 12/20/2022]
Abstract
For cured meat products, nitrite is recognized for its antimicrobial effects against pathogenic bacteria, even though the specific inhibitory mechanisms are not well known. Nitrite contributes to oxidative stress by being the precursor of peroxynitrite (ONOO-), which is the major strong oxidant. Thus, bacterial stress (highly pH-very low partial pressure of oxygen-dependent) is enhanced by the nitrate-nitrite-peroxynitrite system which is also highly pH- and low partial pressure of oxygen-dependent. Nitrite is a hurdle technology which effectiveness depends on several other hurdle technologies including sodium chloride (accelerating the autoxidation of oxymyoglobin and promote peroxynitrite formation), ascorbate (increasing ONOO- synthesis), and Aw. In this environment, certain species are more resistant than others to acidic, oxidative, and nitrative stresses. The most resistant are gram-negative aerobic/facultative anaerobic bacteria (Escherichia coli, Salmonella), and the most fragile are gram-positive anaerobic bacteria (Clostridium botulinum). This position review highlights the major chemical mechanisms involved, the active molecules and their actions on bacterial metabolisms in the meat ecosystem.
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Affiliation(s)
- Didier Majou
- Association pour la Coordination Technique pour l'Industrie Agro-Alimentaire (ACTIA), 16, rue Claude Bernard, 75005 Paris 05, France
| | - Souad Christieans
- Association pour le Développement de l'Industrie de la Viande (ADIV), 10, rue Jacqueline Auriol, 63039 Clermont-Ferrand, France..
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12
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Gotoh A, Nara M, Sugiyama Y, Sakanaka M, Yachi H, Kitakata A, Nakagawa A, Minami H, Okuda S, Katoh T, Katayama T, Kurihara S. Use of Gifu Anaerobic Medium for culturing 32 dominant species of human gut microbes and its evaluation based on short-chain fatty acids fermentation profiles. Biosci Biotechnol Biochem 2017; 81:2009-2017. [PMID: 28782454 DOI: 10.1080/09168451.2017.1359486] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recently, a "human gut microbial gene catalogue," which ranks the dominance of microbe genus/species in human fecal samples, was published. Most of the bacteria ranked in the catalog are currently publicly available; however, the growth media recommended by the distributors vary among species, hampering physiological comparisons among the bacteria. To address this problem, we evaluated Gifu anaerobic medium (GAM) as a standard medium. Forty-four publicly available species of the top 56 species listed in the "human gut microbial gene catalogue" were cultured in GAM, and out of these, 32 (72%) were successfully cultured. Short-chain fatty acids from the bacterial culture supernatants were then quantified, and bacterial metabolic pathways were predicted based on in silico genomic sequence analysis. Our system provides a useful platform for assessing growth properties and analyzing metabolites of dominant human gut bacteria grown in GAM and supplemented with compounds of interest.
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Affiliation(s)
- Aina Gotoh
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan.,b Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | - Misaki Nara
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Yuta Sugiyama
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Mikiyasu Sakanaka
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Hiroyuki Yachi
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Aya Kitakata
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Akira Nakagawa
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Hiromichi Minami
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
| | - Shujiro Okuda
- c Graduate School of Medical and Dental Sciences , Niigata University , Niigata , Japan
| | - Toshihiko Katoh
- b Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | - Takane Katayama
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan.,b Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | - Shin Kurihara
- a Research Institute for Bioresources and Biotechnology , Ishikawa Prefectural University , Nonoichi , Japan
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13
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Dang T, Ingram-Smith C. Investigation of pyrophosphate versus ATP substrate selection in the Entamoeba histolytica acetate kinase. Sci Rep 2017; 7:5912. [PMID: 28724909 PMCID: PMC5517563 DOI: 10.1038/s41598-017-06156-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/08/2017] [Indexed: 12/21/2022] Open
Abstract
Acetate kinase (ACK; E.C. 2.7.2.1), which catalyzes the interconversion of acetate and acetyl phosphate, is nearly ubiquitous in bacteria but is present only in one genus of archaea and certain eukaryotic microbes. All ACKs utilize ATP/ADP as the phosphoryl donor/acceptor in the respective directions of the reaction (acetate + ATP \documentclass[12pt]{minimal}
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\begin{document}$${\boldsymbol{\leftrightarrows }}$$\end{document}⇆ acetyl phosphate + ADP), with the exception of the Entamoeba histolytica ACK (EhACK) which uses pyrophosphate (PPi)/inorganic phosphate (Pi) (acetyl phosphate + Pi
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\begin{document}$${\boldsymbol{\leftrightarrows }}$$\end{document}⇆ acetate + PPi). Structural analysis and modeling of EhACK indicated steric hindrance by active site residues constricts entry to the adenosine pocket as compared to ATP-utilizing Methanosarcina thermophila ACK (MtACK). Reciprocal alterations were made to enlarge the adenosine pocket of EhACK and reduce that of MtACK. The EhACK variants showed a step-wise increase in ADP and ATP binding but were still unable to use these as substrates, and enzymatic activity with Pi/PPi was negatively impacted. Consistent with this, ATP utilization by MtACK variants was negatively affected but the alterations were not sufficient to convert this enzyme to Pi/PPi utilization. Our results suggest that controlling access to the adenosine pocket can contribute to substrate specificity but is not the sole determinant.
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Affiliation(s)
- Thanh Dang
- Department of Genetics and Biochemistry and the Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC, 29634, USA
| | - Cheryl Ingram-Smith
- Department of Genetics and Biochemistry and the Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC, 29634, USA.
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14
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Bar-Even A. Formate Assimilation: The Metabolic Architecture of Natural and Synthetic Pathways. Biochemistry 2016; 55:3851-63. [PMID: 27348189 DOI: 10.1021/acs.biochem.6b00495] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Formate may become an ideal mediator between the physicochemical and biological realms, as it can be produced efficiently from multiple available sources, such as electricity and biomass, and serve as one of the simplest organic compounds for providing both carbon and energy to living cells. However, limiting the realization of formate as a microbial feedstock is the low diversity of formate-fixing enzymes and thereby the small number of naturally occurring formate-assimilation pathways. Here, the natural enzymes and pathways supporting formate assimilation are presented and discussed together with proposed synthetic routes that could permit growth on formate via existing as well as novel formate-fixing reactions. By considering such synthetic routes, the diversity of metabolic solutions for formate assimilation can be expanded dramatically, such that different host organisms, cultivation conditions, and desired products could be matched with the most suitable pathway. Astute application of old and new formate-assimilation pathways may thus become a cornerstone in the development of sustainable strategies for microbial production of value-added chemicals.
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Affiliation(s)
- Arren Bar-Even
- Max Planck Institute of Molecular Plant Physiology , Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
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15
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Mondal SI, Ferdous S, Jewel NA, Akter A, Mahmud Z, Islam MM, Afrin T, Karim N. Identification of potential drug targets by subtractive genome analysis of Escherichia coli O157:H7: an in silico approach. Adv Appl Bioinform Chem 2015; 8:49-63. [PMID: 26677339 PMCID: PMC4677596 DOI: 10.2147/aabc.s88522] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Bacterial enteric infections resulting in diarrhea, dysentery, or enteric fever constitute a huge public health problem, with more than a billion episodes of disease annually in developing and developed countries. In this study, the deadly agent of hemorrhagic diarrhea and hemolytic uremic syndrome, Escherichia coli O157:H7 was investigated with extensive computational approaches aimed at identifying novel and broad-spectrum antibiotic targets. A systematic in silico workflow consisting of comparative genomics, metabolic pathways analysis, and additional drug prioritizing parameters was used to identify novel drug targets that were essential for the pathogen’s survival but absent in its human host. Comparative genomic analysis of Kyoto Encyclopedia of Genes and Genomes annotated metabolic pathways identified 350 putative target proteins in E. coli O157:H7 which showed no similarity to human proteins. Further bio-informatic approaches including prediction of subcellular localization, calculation of molecular weight, and web-based investigation of 3D structural characteristics greatly aided in filtering the potential drug targets from 350 to 120. Ultimately, 44 non-homologous essential proteins of E. coli O157:H7 were prioritized and proved to have the eligibility to become novel broad-spectrum antibiotic targets and DNA polymerase III alpha (dnaE) was the top-ranked among these targets. Moreover, druggability of each of the identified drug targets was evaluated by the DrugBank database. In addition, 3D structure of the dnaE was modeled and explored further for in silico docking with ligands having potential druggability. Finally, we confirmed that the compounds N-coeleneterazine and N-(1,4-dihydro-5H-tetrazol-5-ylidene)-9-oxo-9H-xanthene-2-sulfon-amide were the most suitable ligands of dnaE and hence proposed as the potential inhibitors of this target protein. The results of this study could facilitate the discovery and release of new and effective drugs against E. coli O157:H7 and other deadly human bacterial pathogens.
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Affiliation(s)
- Shakhinur Islam Mondal
- Genetic Engineering and Biotechnology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh ; Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Sabiha Ferdous
- Genetic Engineering and Biotechnology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Nurnabi Azad Jewel
- Genetic Engineering and Biotechnology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Arzuba Akter
- Biochemistry and Molecular Biology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh ; Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Zabed Mahmud
- Genetic Engineering and Biotechnology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Md Muzahidul Islam
- Genetic Engineering and Biotechnology Department, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Tanzila Afrin
- Department of Pharmacy, East West University, Aftabnagar, Bangladesh
| | - Nurul Karim
- Biochemistry and Molecular Biology Department, Jahangirnagar University, Savar, Bangladesh ; Division of Parasitology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
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16
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Moore TC, Escalante-Semerena JC. The EutQ and EutP proteins are novel acetate kinases involved in ethanolamine catabolism: physiological implications for the function of the ethanolamine metabolosome in Salmonella enterica. Mol Microbiol 2015; 99:497-511. [PMID: 26448059 DOI: 10.1111/mmi.13243] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2015] [Indexed: 11/29/2022]
Abstract
Salmonella enterica catabolizes ethanolamine inside a compartment known as the metabolosome. The ethanolamine utilization (eut) operon of this bacterium encodes all functions needed for the assembly and function of this structure. To date, the roles of EutQ and EutP were not known. Herein we show that both proteins have acetate kinase activity and that EutQ is required during anoxic growth of S. enterica on ethanolamine and tetrathionate. EutP and EutQ-dependent ATP synthesis occurred when enzymes were incubated with ADP, Mg(II) ions and acetyl-phosphate. EutQ and EutP also synthesized acetyl-phosphate from ATP and acetate. Although EutP had acetate kinase activity, ΔeutP strains lacked discernible phenotypes under the conditions where ΔeutQ strains displayed clear phenotypes. The kinetic parameters indicate that EutP is a faster enzyme than EutQ. Our evidence supports the conclusion that EutQ and EutP represent novel classes of acetate kinases. We propose that EutQ is necessary to drive flux through the pathway under physiological conditions, preventing a buildup of acetaldehyde. We also suggest that ATP generated by these enzymes may be used as a substrate for EutT, the ATP-dependent corrinoid adenosyltransferase and for the EutA ethanolamine ammonia-lyase reactivase.
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Affiliation(s)
- Theodore C Moore
- Department of Microbiology, University of Georgia, 120 Cedar Street, Athens, GA, 30602, USA
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17
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Rozova ON, Khmelenina VN, Gavletdinova JZ, Mustakhimov II, Trotsenko YA. Acetate kinase-an enzyme of the postulated phosphoketolase pathway in Methylomicrobium alcaliphilum 20Z. Antonie van Leeuwenhoek 2015; 108:965-74. [PMID: 26275877 DOI: 10.1007/s10482-015-0549-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 07/24/2015] [Indexed: 01/10/2023]
Abstract
Recombinant acetate kinase (AcK) was obtained from the aerobic haloalkalitolerant methanotroph Methylomicrobium alcaliphilum 20Z by heterologous expression in Escherichia coli and purification by affinity chromatography. The substrate specificity, the kinetics and oligomeric state of the His6-tagged AcK were determined. The M. alcaliphilum AcK (2 × 45 kDa) catalyzed the reversible phosphorylation of acetate into acetyl phosphate and exhibited a dependence on Mg(2+) or Mn(2+) ions and strong specificity to ATP/ADP. The enzyme showed the maximal activity and high stability at 70 °C. AcK was 20-fold more active in the reaction of acetate synthesis compared to acetate phosphorylation and had a higher affinity to acetyl phosphate (K m 0.11 mM) than to acetate (K m 5.6 mM). The k cat /K m ratios indicated that the enzyme had a remarkably high catalytic efficiency for acetate and ATP formation (k cat/K m = 1.7 × 10(6)) compared to acetate phosphorylation (k cat/K m = 2.5 × 10(3)). The ack gene of M. alcaliphilum 20Z was shown to be co-transcribed with the xfp gene encoding putative phosphoketolase. The Blast analysis revealed the ack and xfp genes in most genomes of the sequenced aerobic methanotrophs, as well as methylotrophic bacteria not growing on methane. The distribution and metabolic role of the postulated phosphoketolase shunted glycolytic pathway in aerobic C1-utilizing bacteria is discussed.
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Affiliation(s)
- Olga N Rozova
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Prospect Nauki 5, Pushchino, 142290, Russia,
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18
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Potential Role of Acetyl-CoA Synthetase (acs) and Malate Dehydrogenase (mae) in the Evolution of the Acetate Switch in Bacteria and Archaea. Sci Rep 2015; 5:12498. [PMID: 26235787 PMCID: PMC4522649 DOI: 10.1038/srep12498] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 06/16/2015] [Indexed: 11/30/2022] Open
Abstract
Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does not exist for the acetate kinase in Bacteria, Archaea, or Eukarya. Here we demonstrate that Archaeal AMP-Acs and ADP-Acs contain paralogous ATPase motifs previously identified in Ack, which demonstrate a novel relation between these proteins in Archaea. The identification of ATPase motif conservation and resulting structural features in AMP- and ADP-acetyl-CoA synthetase proteins in this study expand the ASKHA superfamily to include acetyl-CoA synthetase. Additional phylogenetic analysis showed that Pta and MaeB sequences had a common ancestor, and that the Pta lineage within the halophilc archaea was an ancestral lineage. These results suggested that divergence of a duplicated maeB within an ancient halophilic, archaeal lineage formed a putative pta ancestor. These results provide a potential scenario for the establishment of the Ack/Pta pathway and provide novel insight into the evolution of acetate metabolism for all three domains of life.
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19
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Murthy AMV, Mathivanan S, Chittori S, Savithri HS, Murthy MRN. Structures of substrate- and nucleotide-bound propionate kinase from Salmonella typhimurium: substrate specificity and phosphate-transfer mechanism. ACTA ACUST UNITED AC 2015; 71:1640-8. [PMID: 26249345 DOI: 10.1107/s1399004715009992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/22/2015] [Indexed: 11/11/2022]
Abstract
Kinases are ubiquitous enzymes that are pivotal to many biochemical processes. There are contrasting views on the phosphoryl-transfer mechanism in propionate kinase, an enzyme that reversibly transfers a phosphoryl group from propionyl phosphate to ADP in the final step of non-oxidative catabolism of L-threonine to propionate. Here, X-ray crystal structures of propionate- and nucleotide-bound Salmonella typhimurium propionate kinase are reported at 1.8-2.0 Å resolution. Although the mode of nucleotide binding is comparable to those of other members of the ASKHA superfamily, propionate is bound at a distinct site deeper in the hydrophobic pocket defining the active site. The propionate carboxyl is at a distance of ∼ 5 Å from the γ-phosphate of the nucleotide, supporting a direct in-line transfer mechanism. The phosphoryl-transfer reaction is likely to occur via an associative SN2-like transition state that involves a pentagonal bipyramidal structure with the axial positions occupied by the nucleophile of the substrate and the O atom between the β- and the γ-phosphates, respectively. The proximity of the strictly conserved His175 and Arg236 to the carboxyl group of the propionate and the γ-phosphate of ATP suggests their involvement in catalysis. Moreover, ligand binding does not induce global domain movement as reported in some other members of the ASKHA superfamily. Instead, residues Arg86, Asp143 and Pro116-Leu117-His118 that define the active-site pocket move towards the substrate and expel water molecules from the active site. The role of Ala88, previously proposed to be the residue determining substrate specificity, was examined by determining the crystal structures of the propionate-bound Ala88 mutants A88V and A88G. Kinetic analysis and structural data are consistent with a significant role of Ala88 in substrate-specificity determination. The active-site pocket-defining residues Arg86, Asp143 and the Pro116-Leu117-His118 segment are also likely to contribute to substrate specificity.
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Affiliation(s)
| | - Subashini Mathivanan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Sagar Chittori
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
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20
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Sargo CR, Campani G, Silva GG, Giordano RC, Da Silva AJ, Zangirolami TC, Correia DM, Ferreira EC, Rocha I. Salmonella typhimurium and Escherichia coli dissimilarity: Closely related bacteria with distinct metabolic profiles. Biotechnol Prog 2015; 31:1217-25. [PMID: 26097206 DOI: 10.1002/btpr.2128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/20/2015] [Indexed: 01/17/2023]
Abstract
Live attenuated strains of Salmonella typhimurium have been extensively investigated as vaccines for a number of infectious diseases. However, there is still little information available concerning aspects of their metabolism. S. typhimurium and Escherichia coli show a high degree of similarity in terms of their genome contents and metabolic networks. However, this work presents experimental evidence showing that significant differences exist in their abilities to direct carbon fluxes to biomass and energy production. It is important to study the metabolism of Salmonella to elucidate the formation of acetate and other metabolites involved in optimizing the production of biomass, essential for the development of recombinant vaccines. The metabolism of Salmonella under aerobic conditions was assessed using continuous cultures performed at dilution rates ranging from 0.1 to 0.67 h(-1), with glucose as main substrate. Acetate assimilation and glucose metabolism under anaerobic conditions were also investigated using batch cultures. Chemostat cultivations showed deviation of carbon towards acetate formation, starting at dilution rates above 0.1 h(-1). This differed from previous findings for E. coli, where acetate accumulation was only detected at dilution rates exceeding 0.4 h(-1), and was due to the lower rate of acetate assimilation by S. typhimurium under aerobic conditions. Under anaerobic conditions, both microorganisms mainly produced ethanol, acetate, and formate. A genome-scale metabolic model, reconstructed for Salmonella based on an E. coli model, provided a poor description of the mixed fermentation pattern observed during Salmonella cultures, reinforcing the different patterns of carbon utilization exhibited by these closely related bacteria.
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Affiliation(s)
- Cintia R Sargo
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Gilson Campani
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Gabriel G Silva
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Roberto C Giordano
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Adilson J Da Silva
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Teresa C Zangirolami
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Daniela M Correia
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil.,CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
| | - Eugénio C Ferreira
- CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
| | - Isabel Rocha
- CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
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21
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Ingram-Smith C, Wharton J, Reinholz C, Doucet T, Hesler R, Smith K. The Role of Active Site Residues in ATP Binding and Catalysis in the Methanosarcina thermophila Acetate Kinase. Life (Basel) 2015; 5:861-71. [PMID: 25775277 PMCID: PMC4390882 DOI: 10.3390/life5010861] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/02/2015] [Accepted: 03/04/2015] [Indexed: 11/16/2022] Open
Abstract
Acetate kinase (ACK), which catalyzes the reversible phosphorylation of acetate by ATP, is a member of the acetate and sugar kinase/heat shock cognate/actin (ASKHA) superfamily. ASKHA family members share a common core fold that includes an ATPase domain with five structural motifs. The PHOSPHATE1 motif has previously been shown to be important for catalysis. We have investigated the role of two of these motifs in the Methanosarcina thermophila ACK (MtACK) and have shown that residues projecting into the ACK active site from the PHOSPHATE2 and ADENOSINE loops and a third highly conserved loop designated here as LOOP3 play key roles in nucleotide triphosphate (NTP) selection and utilization. Alteration of Asn211 of PHOSPHATE2, Gly239 of LOOP3, and Gly331 of ADENOSINE greatly reduced catalysis. In particular, Gly331, which is highly conserved throughout the ASKHA superfamily, has the greatest effect on substrate selection. Alteration at this site strongly skewed MtACK toward utilization of purines over pyrimidines, unlike the wild type enzyme that shows broad NTP utilization. Further investigation into differences between the ATPase domain in MtACK and other acetate kinases that show different substrate preferences will provide us with a better understanding of the diversity of phosphoryl donor selection in this enzyme family.
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Affiliation(s)
- Cheryl Ingram-Smith
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
| | - Jeffrey Wharton
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
| | - Christian Reinholz
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
| | - Tara Doucet
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
| | - Rachel Hesler
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
| | - Kerry Smith
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA.
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Chan SHJ, Nørregaard L, Solem C, Jensen PR. Acetate kinase isozymes confer robustness in acetate metabolism. PLoS One 2014; 9:e92256. [PMID: 24638105 PMCID: PMC3956926 DOI: 10.1371/journal.pone.0092256] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/19/2014] [Indexed: 11/18/2022] Open
Abstract
Acetate kinase (ACK) (EC no: 2.7.2.1) interconverts acetyl-phosphate and acetate to either catabolize or synthesize acetyl-CoA dependent on the metabolic requirement. Among all ACK entries available in UniProt, we found that around 45% are multiple ACKs in some organisms including more than 300 species but surprisingly, little work has been done to clarify whether this has any significance. In an attempt to gain further insight we have studied the two ACKs (AckA1, AckA2) encoded by two neighboring genes conserved in Lactococcus lactis (L. lactis) by analyzing protein sequences, characterizing transcription structure, determining enzyme characteristics and effect on growth physiology. The results show that the two ACKs are most likely individually transcribed. AckA1 has a much higher turnover number and AckA2 has a much higher affinity for acetate in vitro. Consistently, growth experiments of mutant strains reveal that AckA1 has a higher capacity for acetate production which allows faster growth in an environment with high acetate concentration. Meanwhile, AckA2 is important for fast acetate-dependent growth at low concentration of acetate. The results demonstrate that the two ACKs have complementary physiological roles in L. lactis to maintain a robust acetate metabolism for fast growth at different extracellular acetate concentrations. The existence of ACK isozymes may reflect a common evolutionary strategy in bacteria in an environment with varying concentrations of acetate.
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Affiliation(s)
| | - Lasse Nørregaard
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Christian Solem
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
- * E-mail: (CS); (PRJ)
| | - Peter Ruhdal Jensen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
- * E-mail: (CS); (PRJ)
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23
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Regulation of acetate kinase isozymes and its importance for mixed-acid fermentation in Lactococcus lactis. J Bacteriol 2014; 196:1386-93. [PMID: 24464460 DOI: 10.1128/jb.01277-13] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Acetate kinase (ACK) converts acetyl phosphate to acetate along with the generation of ATP in the pathway for mixed-acid fermentation in Lactococcus lactis. The reverse reaction yields acetyl phosphate for assimilation purposes. Remarkably, L. lactis has two ACK isozymes, and the corresponding genes are present in an operon. We purified both enzymes (AckA1 and AckA2) from L. lactis MG1363 and determined their oligomeric state, specific activities, and allosteric regulation. Both proteins form homodimeric complexes, as shown by size exclusion chromatography and static light-scattering measurements. The turnover number of AckA1 is about an order of magnitude higher than that of AckA2 for the reaction in either direction. The Km values for acetyl phosphate, ATP, and ADP are similar for both enzymes. However, AckA2 has a higher affinity for acetate than does AckA1, suggesting an important role under acetate-limiting conditions despite the lower activity. Fructose-1,6-bisphosphate, glyceraldehyde-3-phosphate, and phospho-enol-pyruvate inhibit the activities of AckA1 and AckA2 to different extents. The allosteric regulation of AckA1 and AckA2 and the pool sizes of the glycolytic intermediates are consistent with a switch from homolactic to mixed-acid fermentation upon slowing of the growth rate.
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24
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Brandt U, Hiessl S, Schuldes J, Thürmer A, Wübbeler JH, Daniel R, Steinbüchel A. Genome-guided insights into the versatile metabolic capabilities of the mercaptosuccinate-utilizing β-proteobacterium Variovorax paradoxus strain B4. Environ Microbiol 2013; 16:3370-86. [PMID: 24245581 DOI: 10.1111/1462-2920.12340] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/12/2013] [Indexed: 10/26/2022]
Abstract
Variovorax paradoxus B4 is able to utilize 2-mercaptosuccinate (MS) as sole carbon, sulfur and energy source. The whole genome of V. paradoxus B4 was sequenced, annotated and evaluated with special focus on genomic elements related to MS metabolism. The genome encodes two chromosomes harbouring 5 795 261 and 1 353 255 bp. A total of 6753 putative protein-coding sequences were identified. Based on the genome and in combination with results from previous studies, a putative pathway for the degradation of MS could be postulated. The putative molybdopterin oxidoreductase identified during transposon mutagenesis probably catalyses the conversion of MS first into sulfinosuccinate and then into sulfosuccinate by successive transfer of oxygen atoms. Subsequently, the cleavage of sulfosuccinate yields oxaloacetate and sulfite, while the latter is oxidized to sulfate. The expression of the putative molybdopterin oxidoreductase was induced by MS, but not by gluconate, as confirmed by reverse transcriptase polymerase chain reaction. Further, in silico studies combined with experiments and comparative genomics revealed high metabolic diversity of strain B4. It bears a high potential as plant growth-promoting bacterium and as candidate for degradation and detoxification of xenobiotics and other hardly degradable substances. Additionally, the strain is of special interest for production of polythioesters with sulfur-containing precursors as MS.
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Affiliation(s)
- Ulrike Brandt
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität, Corrensstraße 3, Münster, D-48149, Germany
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