1
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Kang SW, Antoney J, Lupton DW, Speight R, Scott C, Jackson CJ. Asymmetric Ene-Reduction by F 420 -Dependent Oxidoreductases B (FDOR-B) from Mycobacterium smegmatis. Chembiochem 2023; 24:e202200797. [PMID: 36716144 DOI: 10.1002/cbic.202200797] [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: 12/29/2022] [Revised: 01/29/2023] [Accepted: 01/30/2023] [Indexed: 01/31/2023]
Abstract
Asymmetric reduction by ene-reductases has received considerable attention in recent decades. While several enzyme families possess ene-reductase activity, the Old Yellow Enzyme (OYE) family has received the most scientific and industrial attention. However, there is a limited substrate range and few stereocomplementary pairs of current ene-reductases, necessitating the development of a complementary class. Flavin/deazaflavin oxidoreductases (FDORs) that use the uncommon cofactor F420 have recently gained attention as ene-reductases for use in biocatalysis due to their stereocomplementarity with OYEs. Although the enzymes of the FDOR-As sub-group have been characterized in this context and reported to catalyse ene-reductions enantioselectively, enzymes from the similarly large, but more diverse, FDOR-B sub-group have not been investigated in this context. In this study, we investigated the activity of eight FDOR-B enzymes distributed across this sub-group, evaluating their specific activity, kinetic properties, and stereoselectivity against α,β-unsaturated compounds. The stereochemical outcomes of the FDOR-Bs are compared with enzymes of the FDOR-A sub-group and OYE family. Computational modelling and induced-fit docking are used to rationalize the observed catalytic behaviour and proposed a catalytic mechanism.
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Affiliation(s)
- Suk Woo Kang
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,Natural Products Research Center, Korea Institute of Science and Technology (KIST), Gangneung, 25451 (Republic of, Korea
| | - James Antoney
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,School of Biology and Environmental Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia.,ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, Queensland, 4000, Australia
| | - David W Lupton
- School of Chemistry, Monash University, Melbourne, Victoria, 3800, Australia
| | - Robert Speight
- School of Biology and Environmental Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia.,ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, Queensland, 4000, Australia
| | - Colin Scott
- Environment, Commonwealth Scientific and Industrial Research Organization, GPO Box 1700, Canberra, ACT 2601, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.,ARC Centre of Excellence in Synthetic Biology, Australian National University, Canberra, ACT 2601, Australia.,ARC Centre of Excellence for Innovations in Peptide and Protein Science, Australian National University, Canberra, ACT 2601, Australia
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2
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Willemse D, Moodley C, Mehra S, Kaushal D. Transcriptional Response of Mycobacterium tuberculosis to Cigarette Smoke Condensate. Front Microbiol 2021; 12:744800. [PMID: 34721344 PMCID: PMC8554204 DOI: 10.3389/fmicb.2021.744800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/13/2021] [Indexed: 11/13/2022] Open
Abstract
Smoking is known to be an added risk factor for tuberculosis (TB), with nearly a quarter of the TB cases attributed to cigarette smokers in the 22 countries with the highest TB burden. Many studies have indicated a link between risk of active TB and cigarette smoke. Smoking is also known to significantly decrease TB cure and treatment completion rate and increase mortality rates. Cigarette smoke contains thousands of volatile compounds including carcinogens, toxins, reactive solids, and oxidants in both particulate and gaseous phase. Yet, to date, limited studies have analyzed the impact of cigarette smoke components on Mycobacterium tuberculosis (Mtb), the causative agent of TB. Here we report the impact of cigarette smoke condensate (CSC) on survival, mutation frequency, and gene expression of Mtb in vitro. We show that exposure of virulent Mtb to cigarette smoke increases the mutation frequency of the pathogen and strongly induces the expression of the regulon controlled by SigH—a global transcriptional regulator of oxidative stress. SigH has previously been shown to be required for Mtb to respond to oxidative stress, survival, and granuloma formation in vivo. A high-SigH expression phenotype is known to be associated with greater virulence of Mtb. In patients with pulmonary TB who smoke, these changes may therefore play an important, yet unexplored, role in the treatment efficacy by potentially enhancing the virulence of tubercle bacilli.
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Affiliation(s)
- Danicke Willemse
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States
| | - Chivonne Moodley
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States.,Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - Smriti Mehra
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States.,Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - Deepak Kaushal
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States
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3
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Mascotti ML, Juri Ayub M, Fraaije MW. On the diversity of F 420 -dependent oxidoreductases: A sequence- and structure-based classification. Proteins 2021; 89:1497-1507. [PMID: 34216160 PMCID: PMC8518648 DOI: 10.1002/prot.26170] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 03/30/2021] [Accepted: 06/26/2021] [Indexed: 11/05/2022]
Abstract
The F420 deazaflavin cofactor is an intriguing molecule as it structurally resembles the canonical flavin cofactor, although behaves as a nicotinamide cofactor due to its obligate hydride-transfer reactivity and similar low redox potential. Since its discovery, numerous enzymes relying on it have been described. The known deazaflavoproteins are taxonomically restricted to Archaea and Bacteria. The biochemistry of the deazaflavoenzymes is diverse and they exhibit great structural variability. In this study a thorough sequence and structural homology evolutionary analysis was performed in order to generate an overarching classification of the F420 -dependent oxidoreductases. Five different deazaflavoenzyme Classes (I-V) are described according to their structural folds as follows: Class I encompassing the TIM-barrel F420 -dependent enzymes; Class II including the Rossmann fold F420 -dependent enzymes; Class III comprising the β-roll F420 -dependent enzymes; Class IV which exclusively gathers the SH3 barrel F420 -dependent enzymes and Class V including the three layer ββα sandwich F420 -dependent enzymes. This classification provides a framework for the identification and biochemical characterization of novel deazaflavoenzymes.
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Affiliation(s)
- María Laura Mascotti
- Molecular Enzymology Group, University of Groningen, Groningen, The Netherlands.,IMIBIO-SL CONICET, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
| | - Maximiliano Juri Ayub
- IMIBIO-SL CONICET, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
| | - Marco W Fraaije
- Molecular Enzymology Group, University of Groningen, Groningen, The Netherlands
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4
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Liu C, Shao M, Osire T, Xu Z, Rao Z. Identification of bottlenecks in 4-androstene-3,17-dione/1,4-androstadiene-3,17-dione synthesis by Mycobacterium neoaurum JC-12 through comparative proteomics. J Biosci Bioeng 2020; 131:264-270. [PMID: 33308966 DOI: 10.1016/j.jbiosc.2020.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/13/2020] [Accepted: 10/20/2020] [Indexed: 11/28/2022]
Abstract
Intermediates such as 4-androstene-3,17-dione (AD) and 1,4-androstadiene-3,17-dione (ADD) have extensive clinical applications in the production of steroid pharmaceuticals. The present study explores the effect of two factors in the production of these intermediates in Mycobacterium neoaurum JC-12: the precursor, phytosterol and a molecule that increases AD/ADD solubility, hydroxypropyl-β-cyclodextrin (HP-β-CD). Differentially expressed proteins were separated and identified using 2D gel electrophoresis (2-DE) and matrix assisted laser desorption/ionization time-of-flight/time-of-flight tandem mass spectrometry (MALDI-TOF/TOF-MS/MS). In total, 31 proteins were identified, and improved expression levels of ten proteins involved in metabolism was induced by phytosterol and/or HP-β-CD, which strengthened the stress resistance of the strain. In the presence of phytosterol and/or HP-β-CD, five proteins involved in the synthesis of AD/ADD, acetyl-CoA acetyltransferase (AAT), alcohol dehydrogenase (ADH), enoyl-CoA hydratase (EH) and short-chain dehydrogenase 1 and 2, increased their expression levels. Reverse transcription-quantitative PCR (RT-qPCR) was used to verify the 2-DE results and the transcriptional level of these five proteins. This analysis identified AAT, ADH, EH, and electron transfer flavoprotein subunit α/β as the possible bottlenecks for AD/ADD synthesis in M. neoaurum JC-12, which therefore are suggested as targets for strain modification.
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Affiliation(s)
- Chao Liu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; Laboratory of Applied Microorganisms and Metabolic Engineering, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Minglong Shao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; Laboratory of Applied Microorganisms and Metabolic Engineering, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Tolbert Osire
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; Laboratory of Applied Microorganisms and Metabolic Engineering, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhenghong Xu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhiming Rao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; Laboratory of Applied Microorganisms and Metabolic Engineering, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
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5
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Shahbaaz M, Potemkin V, Bisetty K, Hassan MI, Hussien MA. Classification and functional analyses of putative virulence factors of Mycobacterium tuberculosis: A combined sequence and structure based study. Comput Biol Chem 2020; 87:107270. [PMID: 32438116 DOI: 10.1016/j.compbiolchem.2020.107270] [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: 09/06/2019] [Revised: 04/16/2020] [Accepted: 04/26/2020] [Indexed: 11/17/2022]
Abstract
The emergence of the drug-resistant mechanisms in Mycobacterium tuberculosis poses the biggest challenges to the current therapeutic measures, which necessitates the identification of new drug targets. The Hypothetical Proteins (HPs), a class of functionally uncharacterized proteins, may provide a new class of undiscovered therapeutic targets. The genome of M. tuberculosis contains 1000 HPs with their sequences were analyzed using a variety of bioinformatics tools and the functional annotations were performed. The functions of 662 HPs were successfully predicted and further classified 483 HPs as enzymes, 141 HPs were predicted to be involved in the diverse cellular mechanisms and 38 HPs may function as transporters and carriers proteins. Furthermore, 28 HPs were predicted to be virulent in nature. Amongst them, the HP P95201, HP P9WM79, HP I6WZ30, HP I6 × 9T8, HP P9WKP3, and HP P9WK89 showed the highest virulence scores. Therefore, these proteins were subjected to extensive structure analyses and dynamics of their conformations were investigated using the principles of molecular dynamics simulations, each for a 150 ns time scale. This study provides a deeper understanding of the undiscovered drug targets and the generated outputs will facilitate the process of drug design and discovery against the infection of M. tuberculosis.
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Affiliation(s)
- Mohd Shahbaaz
- South African Medical Research Council Bioinformatics Unit, South African National Bioinformatics Institute (SANBI), University of the Western Cape, Private Bag X17, Bellville 7535, Cape Town, South Africa; Laboratory of Computational Modeling of Drugs, South Ural State University, 76 Lenin prospekt, 454080 Chelyabinsk, Russia
| | - Vladimir Potemkin
- Laboratory of Computational Modeling of Drugs, South Ural State University, 76 Lenin prospekt, 454080 Chelyabinsk, Russia
| | - Krishna Bisetty
- Department of Chemistry, Durban University of Technology, Durban, 4000, South Africa
| | - Md Imtaiyaz Hassan
- Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi, 110025, India
| | - Mostafa A Hussien
- Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203 Jeddah 21589, Saudi Arabia; Department of Chemistry, Faculty of Science, Port Said University, Port Said, 42521, Egypt
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6
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Cofactor F420-Dependent Enzymes: An Under-Explored Resource for Asymmetric Redox Biocatalysis. Catalysts 2019. [DOI: 10.3390/catal9100868] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The asymmetric reduction of enoates, imines and ketones are among the most important reactions in biocatalysis. These reactions are routinely conducted using enzymes that use nicotinamide cofactors as reductants. The deazaflavin cofactor F420 also has electrochemical properties that make it suitable as an alternative to nicotinamide cofactors for use in asymmetric reduction reactions. However, cofactor F420-dependent enzymes remain under-explored as a resource for biocatalysis. This review considers the cofactor F420-dependent enzyme families with the greatest potential for the discovery of new biocatalysts: the flavin/deazaflavin-dependent oxidoreductases (FDORs) and the luciferase-like hydride transferases (LLHTs). The characterized F420-dependent reductions that have the potential for adaptation for biocatalysis are discussed, and the enzymes best suited for use in the reduction of oxidized cofactor F420 to allow cofactor recycling in situ are considered. Further discussed are the recent advances in the production of cofactor F420 and its functional analog FO-5′-phosphate, which remains an impediment to the adoption of this family of enzymes for industrial biocatalytic processes. Finally, the prospects for the use of this cofactor and dependent enzymes as a resource for industrial biocatalysis are discussed.
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7
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de Oliveira Viana J, Scotti MT, Scotti L. Molecular Docking Studies in Multitarget Antitubercular Drug Discovery. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2018. [DOI: 10.1007/7653_2018_28] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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8
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Tan JL, Ng KP, Ong CS, Ngeow YF. Genomic Comparisons Reveal Microevolutionary Differences in Mycobacterium abscessus Subspecies. Front Microbiol 2017; 8:2042. [PMID: 29109707 PMCID: PMC5660101 DOI: 10.3389/fmicb.2017.02042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/06/2017] [Indexed: 01/01/2023] Open
Abstract
Mycobacterium abscessus, a rapid-growing non-tuberculous mycobacterium, has been the cause of sporadic and outbreak infections world-wide. The subspecies in M. abscessus complex (M. abscessus, M. massiliense, and M. bolletii) are associated with different biologic and pathogenic characteristics and are known to be among the most frequently isolated opportunistic pathogens from clinical material. To date, the evolutionary forces that could have contributed to these biological and clinical differences are still unclear. We compared genome data from 243 M. abscessus strains downloaded from the NCBI ftp Refseq database to understand how the microevolutionary processes of homologous recombination and positive selection influenced the diversification of the M. abscessus complex at the subspecies level. The three subspecies are clearly separated in the Minimum Spanning Tree. Their MUMi-based genomic distances support the separation of M. massiliense and M. bolletii into two subspecies. Maximum Likelihood analysis through dN/dS (the ratio of number of non-synonymous substitutions per non-synonymous site, to the number of synonymous substitutions per synonymous site) identified distinct genes in each subspecies that could have been affected by positive selection during evolution. The results of genome-wide alignment based on concatenated locally-collinear blocks suggest that (a) recombination has affected the M. abscessus complex more than mutation and positive selection; (b) recombination occurred more frequently in M. massiliense than in the other two subspecies; and (c) the recombined segments in the three subspecies have come from different intra-species and inter-species origins. The results lead to the identification of possible gene sets that could have been responsible for the subspecies-specific features and suggest independent evolution among the three subspecies, with recombination playing a more significant role than positive selection in the diversification among members in this complex.
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Affiliation(s)
- Joon L Tan
- Faculty of Information Science and Technology, Multimedia University, Melaka, Malaysia
| | - Kee P Ng
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chia S Ong
- Faculty of Information Science and Technology, Multimedia University, Melaka, Malaysia
| | - Yun F Ngeow
- Department of Pre-clinical Sciences, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Petaling Jaya, Malaysia
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9
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Ankisettypalli K, Cheng JJY, Baker EN, Bashiri G. PdxH proteins of mycobacteria are typical members of the classical pyridoxine/pyridoxamine 5'-phosphate oxidase family. FEBS Lett 2016; 590:453-60. [PMID: 26823273 DOI: 10.1002/1873-3468.12080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/19/2016] [Accepted: 01/20/2016] [Indexed: 11/08/2022]
Abstract
Pyridoxal 5'-phosphate (PLP) biosynthesis is essential for the survival and virulence of Mycobacterium tuberculosis (Mtb). PLP functions as a cofactor for 58 putative PLP-binding proteins encoded by the Mtb genome and could also act as a potential antioxidant. De novo biosynthesis of PLP in Mtb takes place through the 'deoxyxylulose 5'-phosphate (DXP)-independent' pathway, whereas PdxH enzymes, possessing pyridoxine/pyridoxamine 5'-phosphate oxidase (PNPOx) activity, are involved in the PLP salvage pathway. In this study, we demonstrate that the annotated PdxH enzymes from various mycobacterial species are bona fide members of the classical PNPOx enzyme family, capable of producing PLP using both pyridoxine 5'-phosphate (PNP) and pyridoxamine 5'-phosphate (PMP) substrates.
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Affiliation(s)
- Karthik Ankisettypalli
- Structural Biology Laboratory and Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, New Zealand
| | - Jasmin Jo-Yu Cheng
- Structural Biology Laboratory and Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, New Zealand
| | - Edward N Baker
- Structural Biology Laboratory and Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, New Zealand
| | - Ghader Bashiri
- Structural Biology Laboratory and Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, New Zealand
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10
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Li W, Liu M, Xie J. Rv3369 Induces Cytokine Interleukin-1β Production and Enhances Mycobacterium smegmatis Intracellular Survival. J Interferon Cytokine Res 2015; 36:140-7. [PMID: 26588672 DOI: 10.1089/jir.2015.0090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The pathogenesis of tuberculosis, caused by Mycobacterium tuberculosis, is largely because of the pathogen's successful entry and survival within macrophages. We predicted that rv3369, a gene encoding a conserved protein, might play a role in the interactions with host cells. To test this, rv3369 gene was heterologously expressed in a nonpathogenic fast-growing Mycobacterium smegmatis strain. The recombinant strain survives better than the control within macrophages, accompanied by more host cell death and a marked higher secretion of interleukin-1β (IL-1β). Furthermore, pharmacological inhibition experiments showed that the NF-κB and ERK pathways were involved in the Rv3369-triggered IL-1β changes. These results provided evidence for the engagement of Rv3369 in the interaction between mycobacteria and host.
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Affiliation(s)
- Wu Li
- 1 Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing, China .,2 College of Life Sciences, Neijiang Normal University , Neijiang, China
| | - Minqiang Liu
- 1 Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing, China
| | - Jianping Xie
- 1 Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing, China
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11
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Ahmed FH, Carr PD, Lee BM, Afriat-Jurnou L, Mohamed AE, Hong NS, Flanagan J, Taylor MC, Greening C, Jackson CJ. Sequence-Structure-Function Classification of a Catalytically Diverse Oxidoreductase Superfamily in Mycobacteria. J Mol Biol 2015; 427:3554-3571. [PMID: 26434506 DOI: 10.1016/j.jmb.2015.09.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/23/2015] [Accepted: 09/24/2015] [Indexed: 12/11/2022]
Abstract
The deazaflavin cofactor F420 enhances the persistence of mycobacteria during hypoxia, oxidative stress, and antibiotic treatment. However, the identities and functions of the mycobacterial enzymes that utilize F420 under these conditions have yet to be resolved. In this work, we used sequence similarity networks to analyze the distribution of the largest F420-dependent protein family in mycobacteria. We show that these enzymes are part of a larger split β-barrel enzyme superfamily (flavin/deazaflavin oxidoreductases, FDORs) that include previously characterized pyridoxamine/pyridoxine-5'-phosphate oxidases and heme oxygenases. We show that these proteins variously utilize F420, flavin mononucleotide, flavin adenine dinucleotide, and heme cofactors. Functional annotation using phylogenetic, structural, and spectroscopic methods revealed their involvement in heme degradation, biliverdin reduction, fatty acid modification, and quinone reduction. Four novel crystal structures show that plasticity in substrate binding pockets and modifications to cofactor binding motifs enabled FDORs to carry out a variety of functions. This systematic classification and analysis provides a framework for further functional analysis of the roles of FDORs in mycobacterial pathogenesis and persistence.
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Affiliation(s)
- F Hafna Ahmed
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Paul D Carr
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Brendon M Lee
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Livnat Afriat-Jurnou
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - A Elaaf Mohamed
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Nan-Sook Hong
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia
| | - Jack Flanagan
- University of Auckland Faculty of Medical and Health Sciences, 85 Park Road, Grafton, Auckland 2013, New Zealand
| | - Matthew C Taylor
- Commonwealth Scientific and Industrial Research Organisation Land and Water Flagship, Clunies Ross Street, Acton, ACT 2060, Australia
| | - Chris Greening
- Commonwealth Scientific and Industrial Research Organisation Land and Water Flagship, Clunies Ross Street, Acton, ACT 2060, Australia
| | - Colin J Jackson
- Australian National University Research School of Chemistry, Sullivans Creek Road, Acton, ACT 2601, Australia.
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12
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Experimental Evidence for a Revision in the Annotation of Putative Pyridoxamine 5'-Phosphate Oxidases P(N/M)P from Fungi. PLoS One 2015; 10:e0136761. [PMID: 26327315 PMCID: PMC4556617 DOI: 10.1371/journal.pone.0136761] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Accepted: 08/08/2015] [Indexed: 11/19/2022] Open
Abstract
Pyridoxinamine 5'-phosphate oxidases (P(N/M)P oxidases) that bind flavin mononucleotide (FMN) and oxidize pyridoxine 5'-phosphate or pyridoxamine 5'-phosphate to form pyridoxal 5'-phosphate (PLP) are an important class of enzymes that play a central role in cell metabolism. Failure to generate an adequate supply of PLP is very detrimental to most organisms and is often clinically manifested as a neurological disorder in mammals. In this study, we analyzed the function of YLR456W and YPR172W, two homologous genes of unknown function from S. cerevisiae that have been annotated as putative P(N/M)P oxidases based on sequence homology. Different experimental approaches indicated that neither protein catalyzes PLP formation nor binds FMN. On the other hand, our analysis confirmed the enzymatic activity of Pdx3, the S. cerevisiae protein previously implicated in PLP biosynthesis by genetic and structural characterization. After a careful sequence analysis comparing the putative and confirmed P(N/M)P oxidases, we found that the protein domain (PF01243) that led to the YLR456W and YPR172W annotation is a poor indicator of P(N/M)P oxidase activity. We suggest that a combination of two Pfam domains (PF01243 and PF10590) present in Pdx3 and other confirmed P(N/M)P oxidases would be a stronger predictor of this molecular function. This work exemplifies the importance of experimental validation to rectify genome annotation and proposes a revision in the annotation of at least 400 sequences from a wide variety of fungal species that are homologous to YLR456W and are currently misrepresented as putative P(N/M)P oxidases.
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13
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Mashalidis EH, Gittis AG, Tomczak A, Abell C, Barry CE, Garboczi DN. Molecular insights into the binding of coenzyme F420 to the conserved protein Rv1155 from Mycobacterium tuberculosis. Protein Sci 2015; 24:729-40. [PMID: 25644473 DOI: 10.1002/pro.2645] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 01/17/2015] [Accepted: 01/20/2015] [Indexed: 01/01/2023]
Abstract
Coenzyme F420 is a deazaflavin hydride carrier with a lower reduction potential than most flavins. In Mycobacterium tuberculosis (Mtb), F420 plays an important role in activating PA-824, an antituberculosis drug currently used in clinical trials. Although F420 is important to Mtb redox metabolism, little is known about the enzymes that bind F420 and the reactions that they catalyze. We have identified a novel F420 -binding protein, Rv1155, which is annotated in the Mtb genome sequence as a putative flavin mononucleotide (FMN)-binding protein. Using biophysical techniques, we have demonstrated that instead of binding FMN or other flavins, Rv1155 binds coenzyme F420 . The crystal structure of the complex of Rv1155 and F420 reveals one F420 molecule bound to each monomer of the Rv1155 dimer. Structural, biophysical, and bioinformatic analyses of the Rv1155-F420 complex provide clues about its role in the bacterium.
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Affiliation(s)
- Ellene H Mashalidis
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, 20892; Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, United Kingdom
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