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Wahhab BH, Oyewusi HA, Wahab RA, Mohammad Hood MH, Abdul Hamid AA, Al-Nimer MS, Edbeib MF, Kaya Y, Huyop F. Comparative modeling and enzymatic affinity of novel haloacid dehalogenase from Bacillus megaterium strain BHS1 isolated from alkaline Blue Lake in Turkey. J Biomol Struct Dyn 2024; 42:1429-1442. [PMID: 37038649 DOI: 10.1080/07391102.2023.2199870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 04/01/2023] [Indexed: 04/12/2023]
Abstract
This study presents the initial structural model of L-haloacid dehalogenase (DehLBHS1) from Bacillus megaterium BHS1, an alkalotolerant bacterium known for its ability to degrade halogenated environmental pollutants. The model provides insights into the structural features of DehLBHS1 and expands our understanding of the enzymatic mechanisms involved in the degradation of these hazardous pollutants. Key amino acid residues (Arg40, Phe59, Asn118, Asn176, and Trp178) in DehLBHS1 were identified to play critical roles in catalysis and molecular recognition of haloalkanoic acid, essential for efficient binding and transformation of haloalkanoic acid molecules. DehLBHS1 was modeled using I-TASSER, yielding a best TM-score of 0.986 and an RMSD of 0.53 Å. Validation of the model using PROCHECK revealed that 89.2% of the residues were located in the most favored region, providing confidence in its structural accuracy. Molecular docking simulations showed that the non-simulated DehLBHS1 preferred 2,2DCP over other substrates, forming one hydrogen bond with Arg40 and exhibiting a minimum energy of -2.5 kJ/mol. The simulated DehLBHS1 exhibited a minimum energy of -4.3 kJ/mol and formed four hydrogen bonds with Arg40, Asn176, Asp9, and Tyr11, further confirming the preference for 2,2DCP. Molecular dynamics simulations supported this preference, based on various metrics, including RMSD, RMSF, gyration, hydrogen bonding, and molecular distance. MM-PBSA calculations showed that the DehLBHS1-2,2-DCP complex had a markedly lower binding energy (-21.363 ± 1.26 kcal/mol) than the DehLBHS1-3CP complex (-14.327 ± 1.738 kcal/mol). This finding has important implications for the substrate specificity and catalytic function of DehLBHS1, particularly in the bioremediation of 2,2-DCP in contaminated alkaline environments. These results provide a detailed view of the molecular interactions between the enzyme and its substrate and may aid in the development of more efficient biocatalytic strategies for the degradation of halogenated compounds.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Batool Hazim Wahhab
- Department of Microbiology, Faculty of Medicine, Al-Mustansiriyah University, Iraq
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Malaysia
| | - Habeebat Adekilekun Oyewusi
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Malaysia
- Department of Biochemistry, School of Science and Computer Studies, Federal Polytechnic Ado Ekiti, Ekiti State, Nigeria
| | - Roswanira Abdul Wahab
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Malaysia
| | - Mohammad Hakim Mohammad Hood
- Department of Biotechnology, Kulliyah of Science, International Islamic University Malaysia, Kuantan, Pahang, Malaysia
| | - Azzmer Azzar Abdul Hamid
- Department of Biotechnology, Kulliyah of Science, International Islamic University Malaysia, Kuantan, Pahang, Malaysia
| | - Marwan Salih Al-Nimer
- Department of Pharmacology, College of Medicine, University of Diyala, Baqubah, Iraq
| | - Mohamed Faraj Edbeib
- Department of Medical Laboratories, Faculty of Medical Technology, Bani Walid University, Libya
| | - Yilmaz Kaya
- Department of Biology, Faculty of Science, Kyrgyz-Turkish Manas University, Bishkek, Kyrgyzstan
- Department of Agricultural Biotechnology, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey
| | - Fahrul Huyop
- Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Malaysia
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Azemin WA, Alias N, Ali AM, Shamsir MS. Structural and functional characterisation of HepTH1-5 peptide as a potential hepcidin replacement. J Biomol Struct Dyn 2023; 41:681-704. [PMID: 34870559 DOI: 10.1080/07391102.2021.2011415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Hepcidin is a principal regulator of iron homeostasis and its dysregulation has been recognised as a causative factor in cancers and iron disorders. The strategy of manipulating the presence of hepcidin peptide has been used for cancer treatment. However, this has demonstrated poor efficiency and has been short-lived in patients. Many studies reported using minihepcidin therapy as an alternative way to treat hepcidin dysregulation, but this was only applied to non-cancer patients. Highly conserved fish hepcidin protein, HepTH1-5, was investigated to determine its potential use in developing a hepcidin replacement for human hepcidin (Hepc25) and as a therapeutic agent by targeting the tumour suppressor protein, p53, through structure-function analysis. The authors found that HepTH1-5 is stably bound to ferroportin, compared to Hepc25, by triggering the ferroportin internalisation via Lys42 and Lys270 ubiquitination, in a similar manner to the Hepc25 activity. Moreover, the residues Ile24 and Gly24, along with copper and zinc ligands, interacted with similar residues, Lys24 and Asp1 of Hepc25, respectively, showing that those molecules are crucial to the hepcidin replacement strategy. HepTH1-5 interacts with p53 and activates its function through phosphorylation. This finding shows that HepTH1-5 might be involved in the apoptosis signalling pathway upon a DNA damage response. This study will be very helpful for understanding the mechanism of the hepcidin replacement and providing insights into the HepTH1-5 peptide as a new target for hepcidin and cancer therapeutics.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Wan-Atirah Azemin
- School of Agriculture Science and Biotechnology, Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, Besut, Terengganu, Malaysia.,Bioinformatics Research Group (BIRG), Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
| | - Nadiawati Alias
- School of Agriculture Science and Biotechnology, Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, Besut, Terengganu, Malaysia
| | - Abdul Manaf Ali
- School of Agriculture Science and Biotechnology, Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, Besut, Terengganu, Malaysia
| | - Mohd Shahir Shamsir
- Bioinformatics Research Group (BIRG), Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia.,Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia, Pagoh Higher Education Hub, Muar, Johor, Malaysia
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In Silico Analysis on the Interaction of Haloacid Dehalogenase from Bacillus cereus IndB1 with 2-Chloroalkanoic Acid Substrates. ScientificWorldJournal 2022; 2022:1579194. [PMID: 36254337 PMCID: PMC9569217 DOI: 10.1155/2022/1579194] [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: 07/07/2022] [Accepted: 09/08/2022] [Indexed: 11/08/2022] Open
Abstract
Recently, haloacid dehalogenases have gained a lot of interest because of their potential applications in bioremediation and synthesis of chemical products. The haloacid dehalogenase gene from Bacillus cereus IndB1 (bcfd1) has been isolated, expressed, and Bcfd1 enzyme activity towards monochloroacetic acid has been successfully studied. However, the structure, enantioselectivity, substrate range, and essential residues of Bcfd1 have not been elucidated. This research performed computational studies to predict the Bcfd1 protein structure and analyse the interaction of Bcfd1 towards several haloacid substrates to comprehend their enantioselectivity and substrates' range. Structure prediction revealed that Bcfd1 protein consist of two domains. The main domain consists of seven β-sheets connected by six α-helices and four 310-helices forming a Rossmannoid fold. On the other hand, the cap domain consists of five β-sheets connected by five α-helices. The docking simulation showed that 2-chloroalkanoic acids bind to the active site of Bcfd1 with docking energy decreases as the length of their alkyl chain increases. The docking simulation also indicated that the docking energy differences of two enantiomers of 2-chloroalkanoic acids substrates were not significant. Further analysis revealed the role of Met1, Asp2, Cys33, and Lys204 residues in orienting the carboxylic group of 2-chloroalkanoic acids in the active site of this enzyme through hydrogen bonds. This research proved that computational studies could be used to figure out the effect of substrates enantiomer and length of carbon skeleton to Bcfd1 affinity toward 2-chloroalkanoic acids.
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Adamu A, Wahab RA, Aliyu F, Aminu AH, Hamza MM, Huyop F. Haloacid dehalogenases of Rhizobium sp. and related enzymes: Catalytic properties and mechanistic analysis. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Muslem WH, Edbeib MF, Aksoy HM, Kaya Y, Hamid AAA, Hood MHM, Wahab RA, Huyop F. Biodegradation of 3-chloropropionic acid (3-CP) by Bacillus cereus WH2 and its in silico enzyme-substrate docking analysis. J Biomol Struct Dyn 2019; 38:3432-3441. [DOI: 10.1080/07391102.2019.1655482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Wafaa Hassan Muslem
- Department of Biology, College of Science, Al-Mustansiriyah University, Baghdad, Iraq
| | - Mohamed Faraj Edbeib
- Faculty of Agriculture, Department of Animal Production, Baniwalid University, Bani Walid, Libya
- Agricultural Faculty, Department of Plant Protection, Ondokuz Mayis University, Samsun, Turkey
| | - Hasan Murat Aksoy
- Agricultural Faculty, Department of Plant Protection, Ondokuz Mayis University, Samsun, Turkey
| | - Yilmaz Kaya
- Agricultural Faculty, Department of Agricultural Biotechnology, Ondokuz Mayis University, Samsun, Turkey
- Faculty of Science, Department of Biology, Kyrgyz-Turkish Manas University, Bishkek, Kyrgyzstan
| | | | | | - Roswanira Abdul Wahab
- Faculty of Science, Department of Chemistry, Universiti Teknologi Malaysia, Johor Bahru, Malaysia
| | - Fahrul Huyop
- Agricultural Faculty, Department of Agricultural Biotechnology, Ondokuz Mayis University, Samsun, Turkey
- Faculty of Science, Department of Biosciences, Universiti Teknologi Malaysia, Skudai, Malaysia
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The mechanistic role of active site residues in non-stereo haloacid dehalogenase E (DehE). J Mol Graph Model 2019; 90:219-225. [PMID: 31103914 DOI: 10.1016/j.jmgm.2019.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 04/21/2019] [Accepted: 05/06/2019] [Indexed: 11/22/2022]
Abstract
Dehalogenase E (DehE) is a non-stereospecific enzyme produced by the soil bacterium, Rhizobium sp. RC1. Till now, the catalytic mechanism of DehE remains unclear although several literature concerning its structure and function are available. Since DehE is non-stereospecific, the enzyme was hypothesized to follow a 'direct attack mechanism' for the catalytic breakdown of a haloacid. For a molecular insight, the DehE modelled structure was docked in silico with the substrate 2-chloropropionic acid (2CP) in the active site. The ideal position of DehE residues that allowed a direct attack mechanism was then assessed via molecular dynamics (MD) simulation. It was revealed that the essential catalytic water was hydrogen bonded to the 'water-bearer', Asn114, at a relatively constant distance of ∼2.0 Å after 50 ns. The same water molecule was also closely sited to the catalytic Asp189 at an average distance of ∼2.0 Å, signifying the imperative role of the latter to initiate proton abstraction for water activation. This reaction was crucial to promote a direct attack on the α-carbon of 2CP to eject the halide ion. The water molecule was oriented favourably towards the α-carbon of 2CP at an angle of ∼75°, mirrored by the formation of stable enzyme-substrate orientations throughout the simulation. The data therefore substantiated that the degradation of a haloacid by DehE followed a 'direct attack mechanism'. Hence, this study offers valuable information into future advancements in the engineering of haloacid dehalogenases with improved activity and selectivity, as well as functionality in solvents other than water.
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Ang TF, Maiangwa J, Salleh AB, Normi YM, Leow TC. Dehalogenases: From Improved Performance to Potential Microbial Dehalogenation Applications. Molecules 2018; 23:E1100. [PMID: 29735886 PMCID: PMC6100074 DOI: 10.3390/molecules23051100] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 04/07/2018] [Accepted: 04/09/2018] [Indexed: 11/16/2022] Open
Abstract
The variety of halogenated substances and their derivatives widely used as pesticides, herbicides and other industrial products is of great concern due to the hazardous nature of these compounds owing to their toxicity, and persistent environmental pollution. Therefore, from the viewpoint of environmental technology, the need for environmentally relevant enzymes involved in biodegradation of these pollutants has received a great boost. One result of this great deal of attention has been the identification of environmentally relevant bacteria that produce hydrolytic dehalogenases—key enzymes which are considered cost-effective and eco-friendly in the removal and detoxification of these pollutants. These group of enzymes catalyzing the cleavage of the carbon-halogen bond of organohalogen compounds have potential applications in the chemical industry and bioremediation. The dehalogenases make use of fundamentally different strategies with a common mechanism to cleave carbon-halogen bonds whereby, an active-site carboxylate group attacks the substrate C atom bound to the halogen atom to form an ester intermediate and a halide ion with subsequent hydrolysis of the intermediate. Structurally, these dehalogenases have been characterized and shown to use substitution mechanisms that proceed via a covalent aspartyl intermediate. More so, the widest dehalogenation spectrum of electron acceptors tested with bacterial strains which could dehalogenate recalcitrant organohalides has further proven the versatility of bacterial dehalogenators to be considered when determining the fate of halogenated organics at contaminated sites. In this review, the general features of most widely studied bacterial dehalogenases, their structural properties, basis of the degradation of organohalides and their derivatives and how they have been improved for various applications is discussed.
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Affiliation(s)
- Thiau-Fu Ang
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Enzyme and Microbial Technology Research Centre, Centre of Excellence, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Jonathan Maiangwa
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Enzyme and Microbial Technology Research Centre, Centre of Excellence, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Abu Bakar Salleh
- Enzyme and Microbial Technology Research Centre, Centre of Excellence, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Institute of Bioscience, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Yahaya M Normi
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Enzyme and Microbial Technology Research Centre, Centre of Excellence, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Thean Chor Leow
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Enzyme and Microbial Technology Research Centre, Centre of Excellence, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
- Institute of Bioscience, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
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Batumalaie K, Edbeib MF, Mahat NA, Huyop F, Wahab RA. In silico and empirical approaches toward understanding the structural adaptation of the alkaline-stable lipase KV1 from Acinetobacter haemolyticus. J Biomol Struct Dyn 2017; 36:3077-3093. [DOI: 10.1080/07391102.2017.1377635] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Kalaivani Batumalaie
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia
| | - Mohamed Faraj Edbeib
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia
| | - Naji Arafat Mahat
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia
| | - Fahrul Huyop
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia
| | - Roswanira Abdul Wahab
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia
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Manas NHA, Bakar FDA, Illias RM. Computational docking, molecular dynamics simulation and subsite structure analysis of a maltogenic amylase from Bacillus lehensis G1 provide insights into substrate and product specificity. J Mol Graph Model 2016; 67:1-13. [DOI: 10.1016/j.jmgm.2016.04.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/14/2016] [Accepted: 04/18/2016] [Indexed: 10/21/2022]
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Adamu A, Wahab RA, Huyop F. l-2-Haloacid dehalogenase (DehL) from Rhizobium sp. RC1. SPRINGERPLUS 2016; 5:695. [PMID: 27347470 PMCID: PMC4899344 DOI: 10.1186/s40064-016-2328-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 05/11/2016] [Indexed: 11/10/2022]
Abstract
l-2-Haloacid dehalogenase (DehL) from Rhizobium sp. RC1 is a stereospecific enzyme that acts exclusively on l-isomers of 2-chloropropionate and dichloroacetate. The amino acid sequence of this enzyme is substantially different from those of other l-specific dehalogenases produced by other organisms. DehL has not been crystallised, and hence its three-dimensional structure is unavailable. Herein, we review what is known concerning DehL and tentatively identify the amino acid residues important for catalysis based on a comparative structural and sequence analysis with well-characterised l-specific dehalogenases.
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Affiliation(s)
- Aliyu Adamu
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Baharu, Johor Malaysia
| | - Roswanira Abdul Wahab
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Baharu, Johor Malaysia
| | - Fahrul Huyop
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Baharu, Johor Malaysia
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An S188V mutation alters substrate specificity of non-stereospecific α-haloalkanoic acid dehalogenase E (DehE). PLoS One 2015; 10:e0121687. [PMID: 25816329 PMCID: PMC4376737 DOI: 10.1371/journal.pone.0121687] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 02/03/2015] [Indexed: 11/19/2022] Open
Abstract
The non-stereospecific α-haloalkanoic acid dehalogenase E (DehE) degrades many halogenated compounds but is ineffective against β-halogenated compounds such as 3-chloropropionic acid (3CP). Using molecular dynamics (MD) simulations and site-directed mutagenesis we show here that introducing the mutation S188V into DehE improves substrate specificity towards 3CP. MD simulations showed that residues W34, F37, and S188 of DehE were crucial for substrate binding. DehE showed strong binding ability for D-2-chloropropionic acid (D-2CP) and L-2-chloropropionic acid (L-2CP) but less affinity for 3CP. This reduced affinity was attributed to weak hydrogen bonding between 3CP and residue S188, as the carboxylate of 3CP forms rapidly interconverting hydrogen bonds with the backbone amide and side chain hydroxyl group of S188. By replacing S188 with a valine residue, we reduced the inter-molecular distance and stabilised bonding of the carboxylate of 3CP to hydrogens of the substrate-binding residues. Therefore, the S188V can act on 3CP, although its affinity is less strong than for D-2CP and L-2CP as assessed by Km. This successful alteration of DehE substrate specificity may promote the application of protein engineering strategies to other dehalogenases, thereby generating valuable tools for future bioremediation technologies.
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Dhindwal S, Priyadarshini P, Patil DN, Tapas S, Kumar P, Tomar S, Kumar P. Ligand-bound structures of 3-deoxy-D-manno-octulosonate 8-phosphate phosphatase fromMoraxella catarrhalisreveal a water channel connecting to the active site for the second step of catalysis. ACTA ACUST UNITED AC 2015; 71:239-55. [DOI: 10.1107/s1399004714025218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 11/17/2014] [Indexed: 11/10/2022]
Abstract
KdsC, the third enzyme of the 3-deoxy-D-manno-octulosonic acid (KDO) biosynthetic pathway, catalyzes a substrate-specific reaction to hydrolyze 3-deoxy-D-manno-octulosonate 8-phosphate to generate a molecule of KDO and phosphate. KdsC is a phosphatase that belongs to the C0 subfamily of the HAD superfamily. To understand the molecular basis for the substrate specificity of this tetrameric enzyme, the crystal structures of KdsC fromMoraxella catarrhalis(Mc-KdsC) with several combinations of ligands, namely metal ion, citrate and products, were determined. Various transition states of the enzyme have been captured in these crystal forms. The ligand-free and ligand-bound crystal forms reveal that the binding of ligands does not cause any specific conformational changes in the active site. However, the electron-density maps clearly showed that the conformation of KDO as a substrate is different from the conformation adopted by KDO when it binds as a cleaved product. Furthermore, structural evidence for the existence of an intersubunit tunnel has been reported for the first time in the C0 subfamily of enzymes. A role for this tunnel in transferring water molecules from the interior of the tetrameric structure to the active-site cleft has been proposed. At the active site, water molecules are required for the formation of a water bridge that participates as a proton shuttle during the second step of the two-step phosphoryl-transfer reaction. In addition, as the KDO biosynthesis pathway is a potential antibacterial target, pharmacophore-based virtual screening was employed to identify inhibitor molecules for theMc-KdsC enzyme.
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Hamid AAA, Tengku Abdul Hamid TH, Wahab RA, Huyop F. Identification of functional residues essential for dehalogenation by the non-stereospecific α-haloalkanoic acid dehalogenase fromRhizobiumsp. RC1. J Basic Microbiol 2013; 55:324-30. [DOI: 10.1002/jobm.201300526] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Azzmer Azzar Abdul Hamid
- Department of Biotechnology; Kulliyyah of Science, IIUM, Bandar Indera Mahkota; Kuantan Pahang Malaysia
| | | | - Roswanira Abdul Wahab
- Department of Chemistry, Faculty of Science; Universiti Teknologi Malaysia (UTM); Johor Bahru Johor Malaysia
| | - Fahrul Huyop
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering; Universiti Teknologi Malaysia (UTM); Johor Bahru Johor Malaysia
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Bagherbaigi S, Gicana RG, Lamis RJ, Nemati M, Huyop F. Characterisation of Arthrobacter sp. S1 that can degrade α and β-haloalkanoic acids isolated from contaminated soil. ANN MICROBIOL 2013. [DOI: 10.1007/s13213-012-0595-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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