1
|
Nardini M, Pesce A, Bolognesi M. Truncated (2/2) hemoglobin: Unconventional structures and functional roles in vivo and in human pathogenesis. Mol Aspects Med 2021; 84:101049. [PMID: 34776271 DOI: 10.1016/j.mam.2021.101049] [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: 10/22/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 12/12/2022]
Abstract
Truncated hemoglobins (trHbs) build a sub-class of the globin family, found in eubacteria, cyanobacteria, unicellular eukaryotes, and in higher plants; among these, selected human pathogens are found. The trHb fold is based on a 2/2 α-helical sandwich, consisting of a simplified and reduced-size version of the classical 3/3 α-helical sandwich of vertebrate and invertebrate globins. Phylogenetic analysis indicates that trHbs further branch into three groups: group I (or trHbN), group II (or trHbO), and group III (or trHbP), each group being characterized by specific structural features. Among these, a protein matrix tunnel, or a cavity system implicated in diatomic ligand diffusion through the protein matrix, is typical of group I and group II, respectively. In general, a highly intertwined network of hydrogen bonds stabilizes the heme bound ligand, despite variability of the heme distal residues in the different trHb groups. Notably, some organisms display genes from more than one trHb group, suggesting that trHbN, trHbO, and trHbP may support different functions in vivo, such as detoxification of reactive nitrogen and oxygen species, respiration, oxygen storage/sensoring, thus aiding survival of an invading microorganism. Here, structural features and proposed functions of trHbs from human pathogens are reviewed.
Collapse
Affiliation(s)
- Marco Nardini
- Department of Biosciences, University of Milano, Milano, Italy
| | | | | |
Collapse
|
2
|
Pinto GP, Hendrikse NM, Stourac J, Damborsky J, Bednar D. Virtual screening of potential anticancer drugs based on microbial products. Semin Cancer Biol 2021; 86:1207-1217. [PMID: 34298109 DOI: 10.1016/j.semcancer.2021.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/14/2021] [Accepted: 07/18/2021] [Indexed: 01/20/2023]
Abstract
The development of microbial products for cancer treatment has been in the spotlight in recent years. In order to accelerate the lengthy and expensive drug development process, in silico screening tools are systematically employed, especially during the initial discovery phase. Moreover, considering the steadily increasing number of molecules approved by authorities for commercial use, there is a demand for faster methods to repurpose such drugs. Here we present a review on virtual screening web tools, such as publicly available databases of molecular targets and libraries of ligands, with the aim to facilitate the discovery of potential anticancer drugs based on microbial products. We provide an entry-level step-by-step description of the workflow for virtual screening of microbial metabolites with known protein targets, as well as two practical examples using freely available web tools. The first case presents a virtual screening study of drugs developed from microbial products using Caver Web, a web tool that performs docking along a tunnel. The second case comprises a comparative analysis between a wild type isocitrate dehydrogenase 1 and a mutant that results in cancer, using the recently developed web tool PredictSNPOnco. In summary, this review provides the basic and essential background information necessary for virtual screening experiments, which may accelerate the discovery of novel anticancer drugs.
Collapse
Affiliation(s)
- Gaspar P Pinto
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/A13, Brno, 625 00, Czech Republic; International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, Brno, 656 91, Czech Republic
| | - Natalie M Hendrikse
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/A13, Brno, 625 00, Czech Republic
| | - Jan Stourac
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/A13, Brno, 625 00, Czech Republic; International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, Brno, 656 91, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/A13, Brno, 625 00, Czech Republic; International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, Brno, 656 91, Czech Republic
| | - David Bednar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Kamenice 5/A13, Brno, 625 00, Czech Republic; International Clinical Research Center, St. Anne's University Hospital Brno, Pekarska 53, Brno, 656 91, Czech Republic.
| |
Collapse
|
3
|
Pinto GP, Vavra O, Marques SM, Filipovic J, Bednar D, Damborsky J. Screening of world approved drugs against highly dynamical spike glycoprotein of SARS-CoV-2 using CaverDock and machine learning. Comput Struct Biotechnol J 2021; 19:3187-3197. [PMID: 34104357 PMCID: PMC8174816 DOI: 10.1016/j.csbj.2021.05.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/09/2021] [Accepted: 05/25/2021] [Indexed: 12/19/2022] Open
Abstract
The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes pathological pulmonary symptoms. Most efforts to develop vaccines and drugs against this virus target the spike glycoprotein, particularly its S1 subunit, which is recognised by angiotensin-converting enzyme 2. Here we use the in-house developed tool CaverDock to perform virtual screening against spike glycoprotein using a cryogenic electron microscopy structure (PDB-ID: 6VXX) and the representative structures of five most populated clusters from a previously published molecular dynamics simulation. The dataset of ligands was obtained from the ZINC database and consists of drugs approved for clinical use worldwide. Trajectories for the passage of individual drugs through the tunnel of the spike glycoprotein homotrimer, their binding energies within the tunnel, and the duration of their contacts with the trimer's three subunits were computed for the full dataset. Multivariate statistical methods were then used to establish structure-activity relationships and select top candidate for movement inhibition. This new protocol for the rapid screening of globally approved drugs (4359 ligands) in a multi-state protein structure (6 states) showed high robustness in the rate of finished calculations. The protocol is universal and can be applied to any target protein with an experimental tertiary structure containing protein tunnels or channels. The protocol will be implemented in the next version of CaverWeb (https://loschmidt.chemi.muni.cz/caverweb/) to make it accessible to the wider scientific community.
Collapse
Affiliation(s)
- Gaspar P. Pinto
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Centre, St. Ann’s Hospital, Brno, Czech Republic
| | - Ondrej Vavra
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Centre, St. Ann’s Hospital, Brno, Czech Republic
| | - Sergio M. Marques
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Centre, St. Ann’s Hospital, Brno, Czech Republic
| | - Jiri Filipovic
- Institute of Computer Science, Masaryk University, Brno, Czech Republic
| | - David Bednar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Centre, St. Ann’s Hospital, Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Centre, St. Ann’s Hospital, Brno, Czech Republic
| |
Collapse
|
4
|
Municoy M, Roda S, Soler D, Soutullo A, Guallar V. aquaPELE: A Monte Carlo-Based Algorithm to Sample the Effects of Buried Water Molecules in Proteins. J Chem Theory Comput 2020; 16:7655-7670. [PMID: 33201691 DOI: 10.1021/acs.jctc.0c00925] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Water is frequently found inside proteins, carrying out important roles in catalytic reactions or molecular recognition tasks. Therefore, computational models that aim to study protein-ligand interactions usually have to include water effects through explicit or implicit approaches to obtain reliable results. While full explicit models might be too computationally daunting for some applications, implicit models are normally faster but omit some of the most important contributions of water. This is the case of our in-house software, called protein energy landscape exploration (PELE), which uses implicit models to speed up conformational explorations as much as possible; the lack of explicit water sampling, however, limits its model. In this work, we confront this problem with the development of aquaPELE. It is a new algorithm that extends the exploration capabilities while keeping efficiency as it employs a mixed implicit/explicit approach to also take into account the effects of buried water molecules. With an additional Monte Carlo (MC) routine, a set of explicit water molecules is perturbed inside protein cavities and their effects are dynamically adjusted to the current state of the system. As a result, this implementation can be used to predict the principal hydration sites or the rearrangement and displacement of conserved water molecules upon the binding of a ligand. We benchmarked this new tool focusing on estimating ligand binding modes and hydration sites in cavities with important interfacial water molecules, according to crystallographic structures. Results suggest that aquaPELE sets a fast and reliable alternative for molecular recognition studies in systems with a strong water-dependency.
Collapse
Affiliation(s)
- Martí Municoy
- Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain
| | - Sergi Roda
- Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain
| | - Daniel Soler
- Nostrum Biodiscovery, Jordi Girona 29, Nexus II D128, 08034 Barcelona, Spain
| | - Alberto Soutullo
- Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain
| | - Victor Guallar
- Barcelona Supercomputing Center, Jordi Girona 29, E-08034 Barcelona, Spain.,ICREA, Passeig Lluís Companys 23, E-08010 Barcelona, Spain
| |
Collapse
|
5
|
Giordano D, Boubeta FM, di Prisco G, Estrin DA, Smulevich G, Viappiani C, Verde C. Conformational Flexibility Drives Cold Adaptation in Pseudoalteromonas haloplanktis TAC125 Globins. Antioxid Redox Signal 2020; 32:396-411. [PMID: 31578873 DOI: 10.1089/ars.2019.7887] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Significance: Temperature is one of the most important drivers in shaping protein adaptations. Many biochemical and physiological processes are influenced by temperature. Proteins and enzymes from organisms living at low temperature are less stable in comparison to high-temperature adapted proteins. The lower stability is generally due to greater conformational flexibility. Recent Advances: Adaptive changes in the structure of cold-adapted proteins may occur at subunit interfaces, distant from the active site, thus producing energy changes associated with conformational transitions transmitted to the active site by allosteric modulation, valid also for monomeric proteins in which tertiary structural changes may play an essential role. Critical Issues: Despite efforts, the current experimental and computational methods still fail to produce general principles on protein evolution, since many changes are protein and species dependent. Environmental constraints or other biological cellular signals may override the ancestral information included in the structure of the protein, thus introducing inaccuracy in estimates and predictions on the evolutionary adaptations of proteins in response to cold adaptation. Future Directions: In this review, we describe the studies and approaches used to investigate stability and flexibility in the cold-adapted globins of the Antarctic marine bacterium Pseudoalteromonas haloplanktis TAC125. In fact, future research directions will be prescient on more detailed investigation of cold-adapted proteins and the role of fluctuations between different conformational states.
Collapse
Affiliation(s)
- Daniela Giordano
- Institute of Biosciences and BioResources (IBBR), CNR, Napoli, Italy.,Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - Fernando Martín Boubeta
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Guido di Prisco
- Institute of Biosciences and BioResources (IBBR), CNR, Napoli, Italy
| | - Dario A Estrin
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Cristiano Viappiani
- Department of Mathematical, Physical and Computer Sciences, University of Parma, Parma, Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), CNR, Napoli, Italy.,Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Napoli, Italy
| |
Collapse
|
6
|
Díaz L, Soler D, Tresadern G, Buyck C, Perez-Benito L, Saen-Oon S, Guallar V, Soliva R. Monte Carlo simulations using PELE to identify a protein-protein inhibitor binding site and pose. RSC Adv 2020; 10:7058-7064. [PMID: 35493910 PMCID: PMC9049779 DOI: 10.1039/d0ra01127d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/06/2020] [Indexed: 12/18/2022] Open
Abstract
In silico binding site location and pose prediction for a molecule targeted at a large protein surface is a challenging task. We report a blind test with two peptidomimetic molecules that bind the flu virus hemagglutinin (HA) surface antigen, JNJ7918 and JNJ4796 (recently disclosed in van Dongen et al., Science, 2019, 363). Tests with a series of conventional approaches such as rigid (receptor) docking against available X-ray crystal structures or against an ensemble of structures generated by quick methodologies (NMA, homology modeling) gave mixed results, due to the shallowness and flexibility of the binding site and the sheer size of the target. However, tests with our Monte Carlo platform PELE in two protocols involving either exploration of the whole protein surface (global exploration), or the latter followed by refinement of best solutions (local exploration) yielded remarkably good results by locating the actual binding site and generating binding modes that recovered all native contacts found in the X-ray structures. Thus, the Monte Carlo scheme of PELE seems promising as a quick methodology to overcome the challenge of identifying entirely unknown binding sites and modes for protein–protein disruptors. PELE prospectively unveils the binding site and mode of a protein–protein disruptor.![]()
Collapse
Affiliation(s)
- Lucía Díaz
- Nostrum Biodiscovery Jordi Girona 29, Nexus II D128 08034 Barcelona Spain
| | - Daniel Soler
- Nostrum Biodiscovery Jordi Girona 29, Nexus II D128 08034 Barcelona Spain
| | - Gary Tresadern
- Computational Chemistry, Janssen Research & Development, Janssen Pharmaceutica N. V. Turnhoutseweg 30, B-2340 Beerse Belgium
| | - Christophe Buyck
- Computational Chemistry, Janssen Research & Development, Janssen Pharmaceutica N. V. Turnhoutseweg 30, B-2340 Beerse Belgium
| | - Laura Perez-Benito
- Computational Chemistry, Janssen Research & Development, Janssen Pharmaceutica N. V. Turnhoutseweg 30, B-2340 Beerse Belgium
| | - Suwipa Saen-Oon
- Nostrum Biodiscovery Jordi Girona 29, Nexus II D128 08034 Barcelona Spain
| | - Victor Guallar
- Barcelona Supercomputing Center, Join IRB-BSC Program in Computational Biology Spain.,ICREA Passeig Lluís Companys 23 E-08010 Barcelona Spain
| | - Robert Soliva
- Nostrum Biodiscovery Jordi Girona 29, Nexus II D128 08034 Barcelona Spain
| |
Collapse
|
7
|
More than a Confinement: “Soft” and “Hard” Enzyme Entrapment Modulates Biological Catalyst Function. Catalysts 2019. [DOI: 10.3390/catal9121024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Catalysis makes chemical and biochemical reactions kinetically accessible. From a technological point of view, organic, inorganic, and biochemical catalysis is relevant for several applications, from industrial synthesis to biomedical, material, and food sciences. A heterogeneous catalyst, i.e., a catalyst confined in a different phase with respect to the reagents’ phase, requires either its physical confinement in an immobilization matrix or its physical adsorption on a surface. In this review, we will focus on the immobilization of biological catalysts, i.e., enzymes, by comparing hard and soft immobilization matrices and their effect on the modulation of the catalysts’ function. Indeed, unlike smaller molecules, the catalytic activity of protein catalysts depends on their structure, conformation, local environment, and dynamics, properties that can be strongly affected by the immobilization matrices, which, therefore, not only provide physical confinement, but also modulate catalysis.
Collapse
|
8
|
Pinto GP, Vavra O, Filipovic J, Stourac J, Bednar D, Damborsky J. Fast Screening of Inhibitor Binding/Unbinding Using Novel Software Tool CaverDock. Front Chem 2019; 7:709. [PMID: 31737596 PMCID: PMC6828983 DOI: 10.3389/fchem.2019.00709] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 10/09/2019] [Indexed: 11/20/2022] Open
Abstract
Protein tunnels and channels are attractive targets for drug design. Drug molecules that block the access of substrates or release of products can be efficient modulators of biological activity. Here, we demonstrate the applicability of a newly developed software tool CaverDock for screening databases of drugs against pharmacologically relevant targets. First, we evaluated the effect of rigid and flexible side chains on sets of substrates and inhibitors of seven different proteins. In order to assess the accuracy of our software, we compared the results obtained from CaverDock calculation with experimental data previously collected with heat shock protein 90α. Finally, we tested the virtual screening capabilities of CaverDock with a set of oncological and anti-inflammatory FDA-approved drugs with two molecular targets—cytochrome P450 17A1 and leukotriene A4 hydrolase/aminopeptidase. Calculation of rigid trajectories using four processors took on average 53 min per molecule with 90% successfully calculated cases. The screening identified functional tunnels based on the profile of potential energies of binding and unbinding trajectories. We concluded that CaverDock is a sufficiently fast, robust, and accurate tool for screening binding/unbinding processes of pharmacologically important targets with buried functional sites. The standalone version of CaverDock is available freely at https://loschmidt.chemi.muni.cz/caverdock/ and the web version at https://loschmidt.chemi.muni.cz/caverweb/.
Collapse
Affiliation(s)
- Gaspar P Pinto
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czechia.,International Centre for Clinical Research, St. Anne's University Hospital Brno, Brno, Czechia
| | - Ondrej Vavra
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czechia.,International Centre for Clinical Research, St. Anne's University Hospital Brno, Brno, Czechia
| | - Jiri Filipovic
- Institute of Computer Science, Masaryk University, Brno, Czechia
| | - Jan Stourac
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czechia.,International Centre for Clinical Research, St. Anne's University Hospital Brno, Brno, Czechia
| | - David Bednar
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czechia.,International Centre for Clinical Research, St. Anne's University Hospital Brno, Brno, Czechia
| | - Jiri Damborsky
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czechia.,International Centre for Clinical Research, St. Anne's University Hospital Brno, Brno, Czechia
| |
Collapse
|
9
|
Bringas M, Lombardi LE, Luque FJ, Estrin DA, Capece L. Ligand Binding Rate Constants in Heme Proteins Using Markov State Models and Molecular Dynamics Simulations. Chemphyschem 2019; 20:2451-2460. [PMID: 31365183 DOI: 10.1002/cphc.201900589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/30/2019] [Indexed: 11/07/2022]
Abstract
Computer simulation studies of the molecular basis for ligand migration in proteins allow the description of key events such as the transition between docking sites, displacement of existing ligands and solvent molecules, and open/closure of specific "gates", among others. In heme proteins, ligand migration from the solvent to the active site preludes the binding to the heme iron and triggers different functions. In this work, molecular dynamics simulations, a Markov State Model of migration and empirical kinetic equations are combined to study the migration of O2 and NO in two truncated hemoglobins of Mycobacterium tuberculosis (Mt-TrHbN and Mt-TrHbO). For Mt-TrHbN, we show that the difference in the association constant in the oxy and deoxy states relies mainly in the displacement of water molecules anchored in the distal cavity in the deoxy form. The results here provide a valuable approach to study ligand migration in globins.
Collapse
Affiliation(s)
- Mauro Bringas
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EGA, Buenos Aires, Argentina.,Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), C1428EGA, Buenos Aires, Argentina
| | - Leandro E Lombardi
- Instituto de Cálculo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - CONICET, C1428EGA, Buenos Aires, Argentina
| | - F Javier Luque
- Department of Nutrition, Food Sciences and Gastronomy, Faculty of Pharmacy and Food Sciences, University of Barcelona, Campus Torribera, 08921, Santa Coloma de Gramenet, Spain.,Institute of Biomedicine (IBUB) and Institute of Theoretical and Computational Chemistry (IQTCUB), University of Barcelona, 08028, Barcelona, Spain
| | - Darío A Estrin
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EGA, Buenos Aires, Argentina.,Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), C1428EGA, Buenos Aires, Argentina
| | - Luciana Capece
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EGA, Buenos Aires, Argentina.,Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), C1428EGA, Buenos Aires, Argentina
| |
Collapse
|
10
|
Gilabert JF, Lecina D, Estrada J, Guallar V. Monte Carlo Techniques for Drug Design: The Success Case of PELE. BIOMOLECULAR SIMULATIONS IN STRUCTURE-BASED DRUG DISCOVERY 2018. [DOI: 10.1002/9783527806836.ch5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Joan F. Gilabert
- Barcelona Supercomputing Center (BSC); Life Science Department; Jordi Girona 29 08034 Barcelona Spain
| | - Daniel Lecina
- Barcelona Supercomputing Center (BSC); Life Science Department; Jordi Girona 29 08034 Barcelona Spain
| | - Jorge Estrada
- Barcelona Supercomputing Center (BSC); Life Science Department; Jordi Girona 29 08034 Barcelona Spain
| | - Victor Guallar
- Barcelona Supercomputing Center (BSC); Life Science Department; Jordi Girona 29 08034 Barcelona Spain
- ICREA; Passeig Lluís Companys 23 08010 Barcelona Spain
| |
Collapse
|
11
|
Gell DA. Structure and function of haemoglobins. Blood Cells Mol Dis 2017; 70:13-42. [PMID: 29126700 DOI: 10.1016/j.bcmd.2017.10.006] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 12/18/2022]
Abstract
Haemoglobin (Hb) is widely known as the iron-containing protein in blood that is essential for O2 transport in mammals. Less widely recognised is that erythrocyte Hb belongs to a large family of Hb proteins with members distributed across all three domains of life-bacteria, archaea and eukaryotes. This review, aimed chiefly at researchers new to the field, attempts a broad overview of the diversity, and common features, in Hb structure and function. Topics include structural and functional classification of Hbs; principles of O2 binding affinity and selectivity between O2/NO/CO and other small ligands; hexacoordinate (containing bis-imidazole coordinated haem) Hbs; bacterial truncated Hbs; flavohaemoglobins; enzymatic reactions of Hbs with bioactive gases, particularly NO, and protection from nitrosative stress; and, sensor Hbs. A final section sketches the evolution of work on the structural basis for allosteric O2 binding by mammalian RBC Hb, including the development of newer kinetic models. Where possible, reference to historical works is included, in order to provide context for current advances in Hb research.
Collapse
Affiliation(s)
- David A Gell
- School of Medicine, University of Tasmania, TAS 7000, Australia.
| |
Collapse
|
12
|
Bindings of NO, CO, and O 2 to multifunctional globin type dehaloperoxidase follow the 'sliding scale rule'. Biochem J 2017; 474:3485-3498. [PMID: 28899945 DOI: 10.1042/bcj20170515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/06/2017] [Accepted: 09/12/2017] [Indexed: 01/09/2023]
Abstract
Dehaloperoxidase-hemoglobin (DHP), a multifunctional globin protein, not only functions as an oxygen carrier as typical globins such as myoglobin and hemoglobin, but also as a peroxidase, a mono- and dioxygenase, peroxygenase, and an oxidase. Kinetics of DHP binding to NO, CO, and O2 were characterized for wild-type DHP A and B and the H55D and H55V DHP A mutants using stopped-flow methods. All three gaseous ligands bind to DHP significantly more weakly than sperm whale myoglobin (SWMb). Both CO and NO bind to DHP in a one-step process to form a stable six-coordinate complex. Multiple-step NO binding is not observed in DHP, which is similar to observations in SWMb, but in contrast with many heme sensor proteins. The weak affinity of DHP for O2 is mainly due to a fast O2 dissociation rate, in accordance with a longer εN-Fe distance between the heme iron and distal histidine in DHP than that in Mb, and an open-distal pocket that permits ligand escape. Binding affinities in DHP show the same 3-4 orders separation between the pairs NO/CO and CO/O2, consistent with the 'sliding scale rule' hypothesis. Strong gaseous ligand discrimination by DHP is very different from that observed in typical peroxidases, which show poor gaseous ligand selectivity, correlating with a neutral proximal imidazole ligand rather than an imidazolate. The present study provides useful insights into the rationale for DHP to function both as mono-oxygenase and oxidase, and is the first example of a globin peroxidase shown to follow the 'sliding scale rule' hypothesis in gaseous ligand discrimination.
Collapse
|
13
|
Bustamante JP, Szretter ME, Sued M, Martí MA, Estrin DA, Boechi L. A quantitative model for oxygen uptake and release in a family of hemeproteins. Bioinformatics 2016; 32:1805-13. [PMID: 27153569 DOI: 10.1093/bioinformatics/btw083] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 01/30/2016] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION Hemeproteins have many diverse functions that largely depend on the rate at which they uptake or release small ligands, like oxygen. These proteins have been extensively studied using either simulations or experiments, albeit only qualitatively and one or two proteins at a time. RESULTS We present a physical-chemical model, which uses data obtained exclusively from computer simulations, to describe the uptake and release of oxygen in a family of hemeproteins, called truncated hemoglobins (trHbs). Through a rigorous statistical analysis we demonstrate that our model successfully recaptures all the reported experimental oxygen association and dissociation kinetic rate constants, thus allowing us to establish the key factors that determine the rates at which these hemeproteins uptake and release oxygen. We found that internal tunnels as well as the distal site water molecules control ligand uptake, whereas oxygen stabilization by distal site residues controls ligand release. Because these rates largely determine the functions of these hemeproteins, these approaches will also be important tools in characterizing the trHbs members with unknown functions. CONTACT lboechi@ic.fcen.uba.ar SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Juan P Bustamante
- Departamento de Química Inorgánica, Analítica Y Química Física, INQUIMAE-CONICET, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires
| | - María E Szretter
- Instituto De Cálculo, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires Departamento De Matemática, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires
| | - Mariela Sued
- Instituto De Cálculo, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires
| | - Marcelo A Martí
- Departamento De Química Biológica E Instituto De Química Biológica De La Facultad De Ciencias Exactas Y Naturales (IQUIBICEN), Universidad De Buenos Aires, Buenos Aires, Argentina
| | - Darío A Estrin
- Departamento de Química Inorgánica, Analítica Y Química Física, INQUIMAE-CONICET, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires
| | - Leonardo Boechi
- Instituto De Cálculo, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires
| |
Collapse
|
14
|
Hospital A, Goñi JR, Orozco M, Gelpí JL. Molecular dynamics simulations: advances and applications. Adv Appl Bioinform Chem 2015; 8:37-47. [PMID: 26604800 PMCID: PMC4655909 DOI: 10.2147/aabc.s70333] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Molecular dynamics simulations have evolved into a mature technique that can be used effectively to understand macromolecular structure-to-function relationships. Present simulation times are close to biologically relevant ones. Information gathered about the dynamic properties of macromolecules is rich enough to shift the usual paradigm of structural bioinformatics from studying single structures to analyze conformational ensembles. Here, we describe the foundations of molecular dynamics and the improvements made in the direction of getting such ensemble. Specific application of the technique to three main issues (allosteric regulation, docking, and structure refinement) is discussed.
Collapse
Affiliation(s)
- Adam Hospital
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, University of Barcelona, Barcelona, Spain
| | - Josep Ramon Goñi
- Joint BSC-IRB Research Program in Computational Biology, University of Barcelona, Barcelona, Spain ; Barcelona Supercomputing Center, University of Barcelona, Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, University of Barcelona, Barcelona, Spain ; Joint BSC-IRB Research Program in Computational Biology, University of Barcelona, Barcelona, Spain ; Barcelona Supercomputing Center, University of Barcelona, Barcelona, Spain ; Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| | - Josep L Gelpí
- Joint BSC-IRB Research Program in Computational Biology, University of Barcelona, Barcelona, Spain ; Barcelona Supercomputing Center, University of Barcelona, Barcelona, Spain ; Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| |
Collapse
|
15
|
Estarellas Martin C, Seira Castan C, Luque Garriga FJ, Bidon-Chanal Badia A. Understanding the kinetics of ligand binding to globins with molecular dynamics simulations: the necessity of multiple state models. DRUG DISCOVERY TODAY. TECHNOLOGIES 2015; 17:22-27. [PMID: 26724333 DOI: 10.1016/j.ddtec.2015.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/09/2015] [Accepted: 09/14/2015] [Indexed: 06/05/2023]
Abstract
Residue conformational changes and internal cavity migration processes play a key role in regulating the kinetics of ligand migration and binding events in globins. Molecular dynamics simulations have demonstrated their value in the study of these processes in different haemoglobins, but derivation of kinetic data demands the use of more complex techniques like enhanced sampling molecular dynamics methods. This review discusses the different methodologies that are currently applied to study the ligand migration process in globins and highlight those specially developed to derive kinetic data.
Collapse
Affiliation(s)
- Carolina Estarellas Martin
- Departament de Fisicoquímica and Institut de Biomedicina (IBUB), Facultat de Farmàcia, Universitat de Barcelona, Campus de l'Alimentació de Torribera, Santa Coloma de Gramenet, Spain
| | - Constantí Seira Castan
- Departament de Fisicoquímica and Institut de Biomedicina (IBUB), Facultat de Farmàcia, Universitat de Barcelona, Campus de l'Alimentació de Torribera, Santa Coloma de Gramenet, Spain
| | - F Javier Luque Garriga
- Departament de Fisicoquímica and Institut de Biomedicina (IBUB), Facultat de Farmàcia, Universitat de Barcelona, Campus de l'Alimentació de Torribera, Santa Coloma de Gramenet, Spain
| | - Axel Bidon-Chanal Badia
- Departament de Fisicoquímica and Institut de Biomedicina (IBUB), Facultat de Farmàcia, Universitat de Barcelona, Campus de l'Alimentació de Torribera, Santa Coloma de Gramenet, Spain.
| |
Collapse
|
16
|
Boron I, Bustamante JP, Davidge KS, Singh S, Bowman LAH, Tinajero-Trejo M, Carballal S, Radi R, Poole RK, Dikshit K, Estrin DA, Marti MA, Boechi L. Ligand uptake in Mycobacterium tuberculosis truncated hemoglobins is controlled by both internal tunnels and active site water molecules. F1000Res 2015; 4:22. [PMID: 26478812 PMCID: PMC4591903 DOI: 10.12688/f1000research.5921.2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/20/2015] [Indexed: 11/23/2022] Open
Abstract
Mycobacterium tuberculosis, the causative agent of human tuberculosis, has two proteins belonging to the truncated hemoglobin (trHb) family. Mt-trHbN presents well-defined internal hydrophobic tunnels that allow O 2 and •NO to migrate easily from the solvent to the active site, whereas Mt-trHbO possesses tunnels interrupted by a few bulky residues, particularly a tryptophan at position G8. Differential ligand migration rates allow Mt-trHbN to detoxify •NO, a crucial step for pathogen survival once under attack by the immune system, much more efficiently than Mt-trHbO. In order to investigate the differences between these proteins, we performed experimental kinetic measurements, •NO decomposition, as well as molecular dynamics simulations of the wild type Mt-trHbN and two mutants, VG8F and VG8W. These mutations affect both the tunnels accessibility as well as the affinity of distal site water molecules, thus modifying the ligand access to the iron. We found that a single mutation allows Mt-trHbN to acquire ligand migration rates comparable to those observed for Mt-trHbO, confirming that ligand migration is regulated by the internal tunnel architecture as well as by water molecules stabilized in the active site.
Collapse
Affiliation(s)
- Ignacio Boron
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Juan Pablo Bustamante
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Kelly S Davidge
- Centre for Biomolecular Sciences, The University of Nottingham, Nottingham, NG7 2RD, UK
| | - Sandip Singh
- Institute of Microbial Technology, CSIR, Chandigarh, 160036, India
| | - Lesley AH Bowman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK
| | - Mariana Tinajero-Trejo
- Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Sebastián Carballal
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, 11100, Uruguay
| | - Rafael Radi
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, 11100, Uruguay
| | - Robert K Poole
- Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Kanak Dikshit
- Institute of Microbial Technology, CSIR, Chandigarh, 160036, India
| | - Dario A Estrin
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Marcelo A Marti
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Leonardo Boechi
- Instituto de Cálculo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| |
Collapse
|
17
|
Boron I, Bustamante JP, Davidge KS, Singh S, Bowman LAH, Tinajero-Trejo M, Carballal S, Radi R, Poole RK, Dikshit K, Estrin DA, Marti MA, Boechi L. Ligand uptake in Mycobacterium tuberculosis truncated hemoglobins is controlled by both internal tunnels and active site water molecules. F1000Res 2015; 4:22. [PMID: 26478812 PMCID: PMC4591903 DOI: 10.12688/f1000research.5921.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/19/2015] [Indexed: 06/04/2024] Open
Abstract
Mycobacterium tuberculosis, the causative agent of human tuberculosis, has two proteins belonging to the truncated hemoglobin (trHb) family. Mt-trHbN presents well-defined internal hydrophobic tunnels that allow O 2 and (•)NO to migrate easily from the solvent to the active site, whereas Mt-trHbO possesses tunnels that are partially blocked by a few bulky residues, particularly a tryptophan at position G8. Differential ligand migration rates allow Mt-trHbN to detoxify (•)NO, a crucial step for pathogen survival once under attack by the immune system, much more efficiently than Mt-trHbO. In order to investigate the differences between these proteins, we performed experimental kinetic measurements, (•)NO decomposition, as well as molecular dynamics simulations of the wild type Mt-trHbN and two mutants, VG8F and VG8W. These mutations introduce modifications in both tunnel topologies and affect the incoming ligand capacity to displace retained water molecules at the active site. We found that a single mutation allows Mt-trHbN to acquire ligand migration rates comparable to those observed for Mt-trHbO, confirming that ligand migration is regulated by the internal tunnel architecture as well as by water molecules stabilized in the active site.
Collapse
Affiliation(s)
- Ignacio Boron
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Juan Pablo Bustamante
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Kelly S Davidge
- Centre for Biomolecular Sciences, The University of Nottingham, Nottingham, NG7 2RD, UK
| | - Sandip Singh
- Institute of Microbial Technology, CSIR, Chandigarh, 160036, India
| | - Lesley AH Bowman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK
| | - Mariana Tinajero-Trejo
- Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Sebastián Carballal
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, 11100, Uruguay
| | - Rafael Radi
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, 11100, Uruguay
| | - Robert K Poole
- Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Kanak Dikshit
- Institute of Microbial Technology, CSIR, Chandigarh, 160036, India
| | - Dario A Estrin
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Marcelo A Marti
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| | - Leonardo Boechi
- Instituto de Cálculo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, C1428EGA, Argentina
| |
Collapse
|
18
|
Howes BD, Boechi L, Boffi A, Estrin DE, Smulevich G. Bridging Theory and Experiment to Address Structural Properties of Truncated Haemoglobins: Insights from Thermobifida fusca HbO. Adv Microb Physiol 2015; 67:85-126. [PMID: 26616516 DOI: 10.1016/bs.ampbs.2015.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In this chapter, we will discuss the paradigmatic case of Thermobifida fusca (Tf-trHb) HbO in its ferrous and ferric states and its behaviour towards a battery of possible ligands. This choice was dictated by the fact that it has been one of the most extensively studied truncated haemoglobins, both in terms of spectroscopic and molecular dynamics studies. Tf-trHb typifies the structural properties of group II trHbs, as the active site is characterized by a highly polar distal environment in which TrpG8, TyrCD1, and TyrB10 provide three potential H-bond donors in the distal cavity capable of stabilizing the incoming ligands. The role of these residues in key topological positions, and their interplay with the iron-bound ligands, has been addressed in studies carried out on the CO, F(-), OH(-), CN(-), and HS(-) adducts formed with the wild-type protein and a combinatorial set of mutants, in which the distal polar residues, TrpG8, TyrCD1, and TyrB10, have been singly, doubly, or triply replaced by a Phe residue. In this context, such a complete analysis provides an excellent benchmark for the investigation of the relationship between protein structure and function, allowing one to translate physicochemical properties of the active site into the observed functional behaviour. Tf-trHb will be compared with other members of the group II trHbs and, more generally, with members of the other trHb subgroups.
Collapse
Affiliation(s)
- Barry D Howes
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Sesto Fiorentino, Italy
| | - Leonardo Boechi
- Instituto de Cálculo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Alberto Boffi
- Dipartimento di Scienze Biochimiche, Università "Sapienza", Rome, Italy
| | - Dario E Estrin
- Departamento de Química Inorgánica, Analítica y Química Física and Inquimae-Conicet, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Giulietta Smulevich
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Sesto Fiorentino, Italy.
| |
Collapse
|
19
|
Patrizi B, Lapini A, Di Donato M, Marcelli A, Lima M, Righini R, Foggi P, Baiocco P, Bonamore A, Boffi A. Role of local structure and dynamics of small ligand migration in proteins: a study of a mutated truncated hemoprotein from Thermobifida fusca by time resolved MIR spectroscopy. J Phys Chem B 2014; 118:9209-17. [PMID: 25019316 DOI: 10.1021/jp504499b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Carbon monoxide recombination dynamics in a mutant of the truncated hemoglobin from Thermobida fusca (3F-Tf-trHb) has been analyzed by means of ultrafast Visible-pump/MidIR-probe spectroscopy and compared with that of the wild-type protein. In 3F-Tf-trHb, three topologically relevant amino acids, responsible for the ligand stabilization through the formation of a H-bond network (TyrB10 TyrCD1 and TrpG8), have been replaced by Phe residues. X-ray diffraction data show that Phe residues in positions B10 and G8 maintain the same rotameric arrangements as Tyr and Trp in the wild-type protein, while Phe in position CD1 displays significant rotameric heterogeneity. Photodissociation of the ligand has been induced by exciting the sample with 550 nm pump pulses and the CO rebinding has been monitored in two mid-IR regions respectively corresponding to the ν(CO) stretching vibration of the iron-bound CO (1880-1980 cm(-1)) and of the dissociated free CO (2050-2200 cm(-1)). In both the mutant and wild-type protein, a significant amount of geminate CO rebinding is observed on a subnanosecond time scale. Despite the absence of the distal pocket hydrogen-bonding network, the kinetics of geminate rebinding in 3F-Tf-trHb is very similar to the wild-type, showing how the reactivity of dissociated CO toward the heme is primarily regulated by the effective volume and flexibility of the distal pocket and by caging effects exerted on the free CO on the analyzed time scale.
Collapse
Affiliation(s)
- Barbara Patrizi
- LENS (European Laboratory for Nonlinear Spectroscopy) Via N. Carrara 1, Sesto Fiorentino, Florence 50019, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Abstract
Small size globins that have been defined as 'truncated haemoglobins' or as '2/2 haemoglobins' have increasingly been discovered in microorganisms since the early 1990s. Analysis of amino acid sequences allowed to distinguish three groups that collect proteins with specific and common structural properties. All three groups display 3D structures that are based on four main α-helices, which are a subset of the conventional eight-helices globin fold. Specific features, such as the presence of protein matrix tunnels that are held to promote diffusion of functional ligands to/from the haem, distinguish members of the three groups. Haem distal sites vary for their accessibility, local structures, polarity, and ligand stabilization mechanisms, suggesting functional roles that are related to O2/NO chemistry. In a few cases, such activities have been proven in vitro and in vivo through deletion mutants. The issue of 2/2 haemoglobin varied biological functions throughout the three groups remains however fully open.
Collapse
|
21
|
Abstract
The genus Mycobacterium is comprised of Gram-positive bacteria occupying a wide range of natural habitats and includes species that range from severe intracellular pathogens to economically useful and harmless microbes. The recent upsurge in the availability of microbial genome data has shown that genes encoding haemoglobin-like proteins are ubiquitous among Mycobacteria and that multiple haemoglobins (Hbs) of different classes may be present in pathogenic and non-pathogenic species. The occurrence of truncated haemoglobins (trHbs) and flavohaemoglobins (flavoHbs) showing distinct haem active site structures and ligand-binding properties suggests that these Hbs may be playing diverse functions in the cellular metabolism of Mycobacteria. TrHbs and flavoHbs from some of the severe human pathogens such as Mycobacterium tuberculosis and Mycobacterium leprae have been studied recently and their roles in effective detoxification of reactive nitrogen and oxygen species, electron cycling, modulation of redox state of the cell and facilitation of aerobic respiration have been proposed. This multiplicity in the function of Hbs may aid these pathogens to cope with various environmental stresses and survive during their intracellular regime. This chapter provides recent updates on genomic, structural and functional aspects of Mycobacterial Hbs to address their role in Mycobacteria.
Collapse
|
22
|
Bustamante JP, Abbruzzetti S, Marcelli A, Gauto D, Boechi L, Bonamore A, Boffi A, Bruno S, Feis A, Foggi P, Estrin DA, Viappiani C. Ligand uptake modulation by internal water molecules and hydrophobic cavities in hemoglobins. J Phys Chem B 2014; 118:1234-45. [PMID: 24410478 DOI: 10.1021/jp410724z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Internal water molecules play an active role in ligand uptake regulation, since displacement of retained water molecules from protein surfaces or cavities by incoming ligands can promote favorable or disfavorable effects over the global binding process. Detection of these water molecules by X-ray crystallography is difficult given their positional disorder and low occupancy. In this work, we employ a combination of molecular dynamics simulations and ligand rebinding over a broad time range to shed light into the role of water molecules in ligand migration and binding. Computational studies on the unliganded structure of the thermostable truncated hemoglobin from Thermobifida fusca (Tf-trHbO) show that a water molecule is in the vicinity of the iron heme, stabilized by WG8 with the assistance of YCD1, exerting a steric hindrance for binding of an exogenous ligand. Mutation of WG8 to F results in a significantly lower stabilization of this water molecule and in subtle dynamical structural changes that favor ligand binding, as observed experimentally. Water is absent from the fully hydrophobic distal cavity of the triple mutant YB10F-YCD1F-WG8F (3F), due to the lack of residues capable of stabilizing it nearby the heme. In agreement with these effects on the barriers for ligand rebinding, over 97% of the photodissociated ligands are rebound within a few nanoseconds in the 3F mutant case. Our results demonstrate the specific involvement of water molecules in shaping the energetic barriers for ligand migration and binding.
Collapse
Affiliation(s)
- Juan P Bustamante
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires , Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Abbruzzetti S, Spyrakis F, Bidon-Chanal A, Luque FJ, Viappiani C. Ligand migration through hemeprotein cavities: insights from laser flash photolysis and molecular dynamics simulations. Phys Chem Chem Phys 2013; 15:10686-701. [PMID: 23733145 DOI: 10.1039/c3cp51149a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The presence of cavities and tunnels in the interior of proteins, in conjunction with the structural plasticity arising from the coupling to the thermal fluctuations of the protein scaffold, has profound consequences on the pathways followed by ligands moving through the protein matrix. In this perspective we discuss how quantitative analysis of experimental rebinding kinetics from laser flash photolysis, trapping of unstable conformational states by embedding proteins within the nanopores of silica gels, and molecular simulations can synergistically converge to gain insight into the migration mechanism of ligands. We show how the evaluation of the free energy landscape for ligand diffusion based on the outcome of computational techniques can assist the definition of sound reaction schemes, leading to a comprehensive understanding of the broad range of chemical events and time scales that encompass the transport of small ligands in hemeproteins.
Collapse
Affiliation(s)
- Stefania Abbruzzetti
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Parma, viale delle Scienze 7A, 43124, Parma, Italy
| | | | | | | | | |
Collapse
|
24
|
Madadkar-Sobhani A, Guallar V. PELE web server: atomistic study of biomolecular systems at your fingertips. Nucleic Acids Res 2013; 41:W322-8. [PMID: 23729469 PMCID: PMC3692087 DOI: 10.1093/nar/gkt454] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PELE, Protein Energy Landscape Exploration, our novel technology based on protein structure prediction algorithms and a Monte Carlo sampling, is capable of modelling the all-atom protein–ligand dynamical interactions in an efficient and fast manner, with two orders of magnitude reduced computational cost when compared with traditional molecular dynamics techniques. PELE’s heuristic approach generates trial moves based on protein and ligand perturbations followed by side chain sampling and global/local minimization. The collection of accepted steps forms a stochastic trajectory. Furthermore, several processors may be run in parallel towards a collective goal or defining several independent trajectories; the whole procedure has been parallelized using the Message Passing Interface. Here, we introduce the PELE web server, designed to make the whole process of running simulations easier and more practical by minimizing input file demand, providing user-friendly interface and producing abstract outputs (e.g. interactive graphs and tables). The web server has been implemented in C++ using Wt (http://www.webtoolkit.eu) and MySQL (http://www.mysql.com). The PELE web server, accessible at http://pele.bsc.es, is free and open to all users with no login requirement.
Collapse
Affiliation(s)
- Armin Madadkar-Sobhani
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain.
| | | |
Collapse
|
25
|
Spyrakis F, Lucas F, Bidon-Chanal A, Viappiani C, Guallar V, Luque FJ. Comparative analysis of inner cavities and ligand migration in non-symbiotic AHb1 and AHb2. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1957-67. [PMID: 23583621 DOI: 10.1016/j.bbapap.2013.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 03/30/2013] [Accepted: 04/03/2013] [Indexed: 10/27/2022]
Abstract
This study reports a comparative analysis of the topological properties of inner cavities and the intrinsic dynamics of non-symbiotic hemoglobins AHb1 and AHb2 from Arabidopsis thaliana. The two proteins belong to the 3/3 globin fold and have a sequence identity of about 60%. However, it is widely assumed that they have distinct physiological roles. In order to investigate the structure-function relationships in these proteins, we have examined the bis-histidyl and ligand-bound hexacoordinated states by atomistic simulations using in silico structural models. The results allow us to identify two main pathways to the distal cavity in the bis-histidyl hexacoordinated proteins. Nevertheless, a larger accessibility to small gaseous molecules is found in AHb2. This effect can be attributed to three factors: the mutation Leu35(AHb1)→Phe32(AHb2), the enhanced flexibility of helix B, and the more favorable energetic profile for ligand migration to the distal cavity. The net effect of these factors would be to facilitate the access of ligands, thus compensating the preference for the fully hexacoordination of AHb2, in contrast to the equilibrium between hexa- and pentacoordinated species in AHb1. On the other hand, binding of the exogenous ligand introduces distinct structural changes in the two proteins. A well-defined tunnel is formed in AHb1, which might be relevant to accomplish the proposed NO detoxification reaction. In contrast, no similar tunnel is found in AHb2, which can be ascribed to the reduced flexibility of helix E imposed by the larger number of salt bridges compared to AHb1. This feature would thus support the storage and transport functions proposed for AHb2. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
Collapse
Affiliation(s)
- Francesca Spyrakis
- Dipartimento di Scienze degli Alimenti, Università degli Studi di Parma, Parma, Italy.
| | | | | | | | | | | |
Collapse
|
26
|
Small ligand-globin interactions: reviewing lessons derived from computer simulation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1722-38. [PMID: 23470499 DOI: 10.1016/j.bbapap.2013.02.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 02/22/2013] [Accepted: 02/26/2013] [Indexed: 11/24/2022]
Abstract
In this work we review the application of classical and quantum-mechanical atomistic computer simulation tools to the investigation of small ligand interaction with globins. In the first part, studies of ligand migration, with its connection to kinetic association rate constants (kon), are presented. In the second part, we review studies for a variety of ligands such as O2, NO, CO, HS(-), F(-), and NO2(-) showing how the heme structure, proximal effects, and the interactions with the distal amino acids can modulate protein ligand binding. The review presents mainly results derived from our previous works on the subject, in the context of other theoretical and experimental studies performed by others. The variety and extent of the presented data yield a clear example of how computer simulation tools have, in the last decade, contributed to our deeper understanding of small ligand interactions with globins. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
Collapse
|
27
|
Mukhi N, Dhindwal S, Uppal S, Kumar P, Kaur J, Kundu S. X-ray crystallographic structural characteristics of Arabidopsis hemoglobin I and their functional implications. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1944-56. [PMID: 23485912 DOI: 10.1016/j.bbapap.2013.02.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/16/2013] [Accepted: 02/19/2013] [Indexed: 11/24/2022]
Abstract
Genome of the model dicot flowering plant, Arabidopsis thaliana, a popular tool for understanding molecular biology of plant physiology, encodes all three classes of plant hemoglobins that differ in their sequence, ligand binding and spectral properties. As such these globins are of considerable attention. Crystal structures of few members of plant class I nonsymbiotic hemoglobin have been described earlier. Here we report the crystal structure of Arabidopsis class I hemoglobin (AHb1) to 2.2Ǻ and compare its key features with the structures of similar nonsymbiotic hemoglobin from other species. Crystal structure of AHb1 is homologous to the related members with similar globin fold and heme pocket architecture. The structure is homodimeric in the asymmetric unit with both distal and proximal histidines coordinating to the heme iron atom. Residues lining the dimeric interface are also conserved in AHb1 with the exception of additional electrostatic interaction between H112 and E113 of each subunit and that involving Y119 through two water molecules. In addition, differences in heme pocket non-covalent interactions, a novel Ser residue at F7 position, Xe binding site variability, internal cavity topology differences, CD loop conformation and stability and other such properties might explain kinetic variability in AHb1. Detailed cavity analysis of AHb1 showed the presence of a novel long tunnel connecting the distal pockets of both the monomers. Presence of such tunnel, along with conformational heterogeneity observed in the two chains, might suggest cooperative ligand binding and support its role in NO scavenging. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
Collapse
Affiliation(s)
- Nitika Mukhi
- Department of Genetics, University of Delhi South Campus, New Delhi, India
| | | | | | | | | | | |
Collapse
|
28
|
Modifying the catalytic preference of tributyrin in Bacillus thermocatenulatus lipase through in-silico modeling of enzyme-substrate complex. Protein Eng Des Sel 2013; 26:325-33. [DOI: 10.1093/protein/gzt004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
29
|
Hospital A, Gelpi JL. High-throughput molecular dynamics simulations: toward a dynamic view of macromolecular structure. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2013. [DOI: 10.1002/wcms.1142] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
30
|
Lucas MF, Guallar V. Single vs. multiple ligand pathways in globins: a computational view. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1739-43. [PMID: 23388390 DOI: 10.1016/j.bbapap.2013.01.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 01/25/2013] [Accepted: 01/28/2013] [Indexed: 11/30/2022]
Abstract
Diatomic ligand migration in globins has been the subject of numerous studies. Still, a consensus picture for the ligand entrance is not clear, with a growing concern among experimental researchers that computational simulations always show multiple pathways for any globin. Modeling non-biased ligand entrance from conventional molecular dynamics techniques, however, has shown to be difficult (and expensive). Here we use our Monte Carlo methodology, capable of freely mapping ligand diffusion and the description of rare events, to two well-studied systems: myoglobin and the mini-hemoglobin from the sea worm Cerebratulus lacteus. Our results clearly show that the simulations are specific to the system providing a different trend in the entrance pathway, as expected from experiments. While Mb presents multiple entrance pathways, populating the well-known xenon cavities, in CerHb the ligand enters the protein only by one apolar channel. Most of the trajectories (64%) visiting myoglobin's active site though, are gated by the distal histidine. Such detailed information, accessible through the state of the art algorithms in PELE, is computationally inexpensive and available to all non-profit researchers. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.
Collapse
Affiliation(s)
- M Fátima Lucas
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | | |
Collapse
|
31
|
Lapini A, Di Donato M, Patrizi B, Marcelli A, Lima M, Righini R, Foggi P, Sciamanna N, Boffi A. Carbon monoxide recombination dynamics in truncated hemoglobins studied with visible-pump midIR-probe spectroscopy. J Phys Chem B 2012; 116:8753-61. [PMID: 22759230 DOI: 10.1021/jp3019149] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Carbon monoxide recombination dynamics upon photodissociation with visible light has been characterized by means of ultrafast visible-pump/MidIR probe spectroscopy for the truncated hemoglobins from Thermobifida fusca and Bacillus subtilis. Photodissociation has been induced by exciting the sample at two different wavelengths: 400 nm, corresponding to the heme absorption in the B-band, and 550 nm, in the Q-bands. The bleached iron-CO coordination band located at 1850-1950 cm(-1) and the free CO absorption band in the region 2050-2200 cm(-1) have been observed by probe pulses tuned in the appropriate infrared region. The kinetic traces measured at 1850-1950 cm(-1) reveal multiexponential subnanosecond dynamics that have been interpreted as arising from fast geminate recombination of the photolyzed CO. A compared analysis of the crystal structure of the two proteins reveals a similar structure of their distal heme pocket, which contains conserved polar and aromatic amino acid residues closely interacting with the iron ligand. Although fast geminate recombination is observed in both proteins, several kinetic differences can be evidenced, which can be interpreted in terms of a different structural flexibility of the corresponding heme distal pockets. The analysis of the free CO band-shape and of its dynamic evolution brings out novel features about the nature of the docking site inside the protein cavity.
Collapse
Affiliation(s)
- Andrea Lapini
- LENS (European Laboratory for Nonlinear Spectroscopy), via N. Carrara 1, 50019 Sesto Fiorentino (FI), Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Marcelli A, Abbruzzetti S, Bustamante JP, Feis A, Bonamore A, Boffi A, Gellini C, Salvi PR, Estrin DA, Bruno S, Viappiani C, Foggi P. Following ligand migration pathways from picoseconds to milliseconds in type II truncated hemoglobin from Thermobifida fusca. PLoS One 2012; 7:e39884. [PMID: 22792194 PMCID: PMC3391200 DOI: 10.1371/journal.pone.0039884] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 05/28/2012] [Indexed: 11/18/2022] Open
Abstract
CO recombination kinetics has been investigated in the type II truncated hemoglobin from Thermobifida fusca (Tf-trHb) over more than 10 time decades (from 1 ps to ∼100 ms) by combining femtosecond transient absorption, nanosecond laser flash photolysis and optoacoustic spectroscopy. Photolysis is followed by a rapid geminate recombination with a time constant of ∼2 ns representing almost 60% of the overall reaction. An additional, small amplitude geminate recombination was identified at ∼100 ns. Finally, CO pressure dependent measurements brought out the presence of two transient species in the second order rebinding phase, with time constants ranging from ∼3 to ∼100 ms. The available experimental evidence suggests that the two transients are due to the presence of two conformations which do not interconvert within the time frame of the experiment. Computational studies revealed that the plasticity of protein structure is able to define a branched pathway connecting the ligand binding site and the solvent. This allowed to build a kinetic model capable of describing the complete time course of the CO rebinding kinetics to Tf-trHb.
Collapse
Affiliation(s)
- Agnese Marcelli
- LENS, European Laboratory for Non-linear Spectroscopy, Florence, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Jasaitis A, Ouellet H, Lambry JC, Martin JL, Friedman JM, Guertin M, Vos MH. Ultrafast heme–ligand recombination in truncated hemoglobin HbO from Mycobacterium tuberculosis: A ligand cage. Chem Phys 2012. [DOI: 10.1016/j.chemphys.2011.04.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
34
|
Lucas MF, Guallar V. An atomistic view on human hemoglobin carbon monoxide migration processes. Biophys J 2012; 102:887-96. [PMID: 22385860 DOI: 10.1016/j.bpj.2012.01.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 01/02/2012] [Accepted: 01/11/2012] [Indexed: 10/28/2022] Open
Abstract
A significant amount of work has been devoted to obtaining a detailed atomistic knowledge of the human hemoglobin mechanism. Despite this impressive research, to date, the ligand diffusion processes remain unclear and controversial. Using recently developed computational techniques, PELE, we are capable of addressing the ligand migration processes. First, the methodology was tested on myoglobin's CO migration, and the results were compared with the wealth of theoretical and experimental studies. Then, we explored both hemoglobin tense and relaxed states and identified the differences between the α-and β-subunits. Our results indicate that the proximal site, equivalent to the Xe1 cavity in myoglobin, is never visited. Furthermore, strategically positioned residues alter the diffusion processes within hemoglobin's subunits and suggest that multiple pathways exist, especially diversified in the α-globins. A significant dependency of the ligand dynamics on the tertiary structure is also observed.
Collapse
Affiliation(s)
- M Fátima Lucas
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | | |
Collapse
|
35
|
Cossins BP, Hosseini A, Guallar V. Exploration of Protein Conformational Change with PELE and Meta-Dynamics. J Chem Theory Comput 2012; 8:959-65. [PMID: 26593358 DOI: 10.1021/ct200675g] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atomistic molecular simulation methods are now able to explore complex protein or protein-ligand dynamical space in a tractable way with methods such as meta-dynamics or adaptive biasing force. However, many of these methods either require a careful selection of reaction coordinates or the knowledge of an initial pathway of some kind. Thus, it is important that effective methods are developed to produce this pathway data in an efficient fashion. PELE, a proven protein-ligand sampling code, has been developed to provide rapid protein sampling in highly flexible cases, using a reduced network model eigen problem approach. The resulting method is able to rapidly sample configuration space with very general driving information. When applied to ubiquitin, PELE was able to reproduce RMSD and average force data found in molecular dynamics simulations. PELE was also applied to explore the opening/closing transition of T4 lysozyme. A meta-dynamics exploration using a low energy pathway validated that the configurations explored by PELE represent the most populated regions of phase space. PELE and meta-dynamics explorations also discovered a low free energy region where a large cross-domain helix of T4 lysozyme is broken in two. There is previous NMR evidence for the validity of this unfolded helix region.
Collapse
Affiliation(s)
- Benjamin P Cossins
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, c/Jordi Girona 29,08034 Barcelona, Spain
| | - Ali Hosseini
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, c/Jordi Girona 29,08034 Barcelona, Spain
| | - Victor Guallar
- Joint BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, c/Jordi Girona 29,08034 Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain
| |
Collapse
|
36
|
Hernández-Ortega A, Lucas F, Ferreira P, Medina M, Guallar V, Martínez AT. Modulating O2 reactivity in a fungal flavoenzyme: involvement of aryl-alcohol oxidase Phe-501 contiguous to catalytic histidine. J Biol Chem 2011; 286:41105-14. [PMID: 21940622 DOI: 10.1074/jbc.m111.282467] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aryl-alcohol oxidase (AAO) is a flavoenzyme responsible for activation of O(2) to H(2)O(2) in fungal degradation of lignin. The AAO crystal structure shows a buried active site connected to the solvent by a hydrophobic funnel-shaped channel, with Phe-501 and two other aromatic residues forming a narrow bottleneck that prevents the direct access of alcohol substrates. However, ligand diffusion simulations show O(2) access to the active site following this channel. Site-directed mutagenesis of Phe-501 yielded a F501A variant with strongly reduced O(2) reactivity. However, a variant with increased reactivity, as shown by kinetic constants and steady-state oxidation degree, was obtained by substitution of Phe-501 with tryptophan. The high oxygen catalytic efficiency of F501W, ∼2-fold that of native AAO and ∼120-fold that of F501A, seems related to a higher O(2) availability because the turnover number was slightly decreased with respect to the native enzyme. Free diffusion simulations of O(2) inside the active-site cavity of AAO (and several in silico Phe-501 variants) yielded >60% O(2) population at 3-4 Å from flavin C4a in F501W compared with 44% in AAO and only 14% in F501A. Paradoxically, the O(2) reactivity of AAO decreased when the access channel was enlarged and increased when it was constricted by introducing a tryptophan residue. This is because the side chain of Phe-501, contiguous to the catalytic histidine (His-502 in AAO), helps to position O(2) at an adequate distance from flavin C4a (and His-502 Nε). Phe-501 substitution with a bulkier tryptophan residue resulted in an increase in the O(2) reactivity of this flavoenzyme.
Collapse
Affiliation(s)
- Aitor Hernández-Ortega
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | | | | | | | | | | |
Collapse
|
37
|
Chen H, Lai W, Shaik S. Multireference and multiconfiguration ab initio methods in heme-related systems: what have we learned so far? J Phys Chem B 2011; 115:1727-42. [PMID: 21344948 DOI: 10.1021/jp110016u] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
This work reviews the recent applications of ab initio multireference/multiconfiguration (MR/MC) electronic structure methods to heme-related systems, involving tetra-, penta-, and hexa-coordinate species, as well as the high-valent iron-oxo species. The current accuracy of these methods in the various systems is discussed, with special attention to potential sources of systematic errors. Thus, the review summarizes and tries to rationalize the key elements of MR/MC calculations, namely, the choice of the employed active space, especially the so-called double-shell effect that has already been recognized to be important in transition-metal-containing systems, and the impact of these elements on the spin-state energetics of heme species, as well as on the bonding mechanism of small molecules to the heme. It is shown that expansion of the MC wave function into one based on localized orbitals provides a compact and insightful view on some otherwise complex electronic structures. The effects of protein environment on the MR/MC results are summarized for the few available quantum mechanical/molecular mechanical (QM/MM) studies. Comparisons with corresponding DFT results are also made wherever available. Potential future directions are proposed.
Collapse
Affiliation(s)
- Hui Chen
- Institute of Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel.
| | | | | |
Collapse
|
38
|
Mañez PA, Lu C, Boechi L, Martí MA, Shepherd M, Wilson JL, Poole RK, Luque FJ, Yeh SR, Estrin DA. Role of the distal hydrogen-bonding network in regulating oxygen affinity in the truncated hemoglobin III from Campylobacter jejuni. Biochemistry 2011; 50:3946-56. [PMID: 21476539 PMCID: PMC4535342 DOI: 10.1021/bi101137n] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Oxygen affinity in heme-containing proteins is determined by a number of factors, such as the nature and conformation of the distal residues that stabilize the heme bound-oxygen via hydrogen-bonding interactions. The truncated hemoglobin III from Campylobacter jejuni (Ctb) contains three potential hydrogen-bond donors in the distal site: TyrB10, TrpG8, and HisE7. Previous studies suggested that Ctb exhibits an extremely slow oxygen dissociation rate due to an interlaced hydrogen-bonding network involving the three distal residues. Here we have studied the structural and kinetic properties of the G8(WF) mutant of Ctb and employed state-of-the-art computer simulation methods to investigate the properties of the O(2) adduct of the G8(WF) mutant, with respect to those of the wild-type protein and the previously studied E7(HL) and/or B10(YF) mutants. Our data indicate that the unique oxygen binding properties of Ctb are determined by the interplay of hydrogen-bonding interactions between the heme-bound ligand and the surrounding TyrB10, TrpG8, and HisE7 residues.
Collapse
Affiliation(s)
- Pau Arroyo Mañez
- Departamento de Química Inorgánica, Analítica, y Química Fisica, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Changyuan Lu
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Leonardo Boechi
- Departamento de Química Inorgánica, Analítica, y Química Fisica, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Marcelo A. Martí
- Departamento de Química Inorgánica, Analítica, y Química Fisica, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| | - Mark Shepherd
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - Jayne Louise Wilson
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - Robert K. Poole
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - F. Javier Luque
- Department de Fisicoquimica and Institut de Biomedicina (IBUB), Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - Syun-Ru Yeh
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Darío A. Estrin
- Departamento de Química Inorgánica, Analítica, y Química Fisica, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Universitaria, Buenos Aires, Argentina
| |
Collapse
|
39
|
Substrate diffusion and oxidation in GMC oxidoreductases: an experimental and computational study on fungal aryl-alcohol oxidase. Biochem J 2011; 436:341-50. [DOI: 10.1042/bj20102090] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AAO (aryl-alcohol oxidase) provides H2O2 in fungal degradation of lignin, a process of high biotechnological interest. The crystal structure of AAO does not show open access to the active site, where different aromatic alcohols are oxidized. In the present study we investigated substrate diffusion and oxidation in AAO compared with the structurally related CHO (choline oxidase). Cavity finder and ligand diffusion simulations indicate the substrate-entrance channel, requiring side-chain displacements and involving a stacking interaction with Tyr92. Mixed QM (quantum mechanics)/MM (molecular mechanics) studies combined with site-directed mutagenesis showed two active-site catalytic histidine residues, whose substitution strongly decreased both catalytic and transient-state reduction constants for p-anisyl alcohol in the H502A (over 1800-fold) and H546A (over 35-fold) variants. Combination of QM/MM energy profiles, protonation predictors, molecular dynamics, mutagenesis and pH profiles provide a robust answer regarding the nature of the catalytic base. The histidine residue in front of the FAD ring, AAO His502 (and CHO His466), acts as a base. For the two substrates assayed, it was shown that proton transfer preceded hydride transfer, although both processes are highly coupled. No stable intermediate was observed in the energy profiles, in contrast with that observed for CHO. QM/MM, together with solvent KIE (kinetic isotope effect) results, suggest a non-synchronous concerted mechanism for alcohol oxidation by AAO.
Collapse
|
40
|
Forti F, Boechi L, Estrin DA, Marti MA. Comparing and combining implicit ligand sampling with multiple steered molecular dynamics to study ligand migration processes in heme proteins. J Comput Chem 2011; 32:2219-31. [DOI: 10.1002/jcc.21805] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 01/18/2011] [Accepted: 03/06/2011] [Indexed: 12/30/2022]
|
41
|
Heroux MS, Mohan AD, Olsen KW. Ligand migration in the truncated hemoglobin of Mycobacterium tuberculosis. IUBMB Life 2011; 63:214-20. [DOI: 10.1002/iub.438] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
42
|
Wallrapp FH, Guallar V. Mixed quantum mechanics and molecular mechanics methods: Looking inside proteins. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.27] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
43
|
Droghetti E, Nicoletti FP, Bonamore A, Boechi L, Arroyo Mañez P, Estrin DA, Boffi A, Smulevich G, Feis A. Heme pocket structural properties of a bacterial truncated hemoglobin from Thermobifida fusca. Biochemistry 2010; 49:10394-402. [PMID: 21049911 DOI: 10.1021/bi101452k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An acidic surface variant (ASV) of the "truncated" hemoglobin from Thermobifida fusca was designed with the aim of creating a versatile globin scaffold endowed with thermostability and a high level of recombinant expression in its soluble form while keeping the active site unmodified. This engineered protein was obtained by mutating the surface-exposed residues Phe107 and Arg91 to Glu. Molecular dynamics simulations showed that the mutated residues remain solvent-exposed, not affecting the overall protein structure. Thus, the ASV was used in a combinatorial mutagenesis of the distal heme pocket residues in which one, two, or three of the conserved polar residues [TyrB10(54), TyrCD1(67), and TrpG8(119)] were substituted with Phe. Mutants were characterized by infrared and resonance Raman spectroscopy and compared with the wild-type protein. Similar Fe-proximal His stretching frequencies suggest that none of the mutations alters the proximal side of the heme cavity. Two conformers were observed in the spectra of the CO complexes of both wild-type and ASV protein: form 1 with ν(FeC) and ν(CO) at 509 and 1938 cm(-1) and form 2 with ν(FeC) and ν(CO) at 518 and 1920 cm(-1), respectively. Molecular dynamics simulations were performed for the wild-type and ASV forms, as well as for the TyrB10 mutant. The spectroscopic and computational results demonstrate that CO interacts with TrpG8 in form 1 and interacts with both TrpG8 and TyrCD1 in form 2. TyrB10 does not directly interact with the bound CO.
Collapse
Affiliation(s)
- Enrica Droghetti
- Dipartimento di Chimica Ugo Schiff, Università di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino (FI), Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Arroyo-Mañez P, Bikiel DE, Boechi L, Capece L, Di Lella S, Estrin DA, Martí MA, Moreno DM, Nadra AD, Petruk AA. Protein dynamics and ligand migration interplay as studied by computer simulation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1814:1054-64. [PMID: 20797453 DOI: 10.1016/j.bbapap.2010.08.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 08/12/2010] [Accepted: 08/13/2010] [Indexed: 10/19/2022]
Abstract
Since proteins are dynamic systems in living organisms, the employment of methodologies contemplating this crucial characteristic results fundamental to allow revealing several aspects of their function. In this work, we present results obtained using classical mechanical atomistic simulation tools applied to understand the connection between protein dynamics and ligand migration. Firstly, we will present a review of the different sampling schemes used in the last years to obtain both ligand migration pathways and the thermodynamic information associated with the process. Secondly, we will focus on representative examples in which the schemes previously presented are employed, concerning the following: i) ligand migration, tunnels, and cavities in myoglobin and neuroglobin; ii) ligand migration in truncated hemoglobin members; iii) NO escape and conformational changes in nitrophorins; iv) ligand selectivity in catalase and hydrogenase; and v) larger ligand migration: the P450 and haloalkane dehalogenase cases. This article is part of a Special Issue entitled: Protein Dynamics: Experimental and Computational Approaches.
Collapse
Affiliation(s)
- Pau Arroyo-Mañez
- Departamento de Química Inorgánica, Analítica y Química-Física (INQUIMAE-CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Guallar V, Wallrapp FH. QM/MM methods: looking inside heme proteins biochemistry. Biophys Chem 2010; 149:1-11. [PMID: 20400222 DOI: 10.1016/j.bpc.2010.03.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 03/15/2010] [Accepted: 03/16/2010] [Indexed: 11/29/2022]
Abstract
Mixed quantum mechanics/molecular mechanics methods offer a valuable computational tool for understanding biochemical events. When combined with conformational sampling techniques, they allow for an exhaustive exploration of the enzymatic mechanism. Heme proteins are ubiquitous and essential for every organism. In this review we summarize our efforts towards the understanding of heme biochemistry. We present: 1) results on ligand migration on globins coupled to the ligand binding event, 2) results on the localization of the spin density in compound I of cytochromes and peroxidases, 3) novel methodologies for mapping the electron transfer pathways and 4) novel data on Tryptophan 2,3-dioxygenase. For this enzyme our results strongly indicate that the distal oxygen will end up on the C3 indole carbon, whereas the proximal oxygen will end up in the C2 position. Interestingly, the process involves the formation of an epoxide and a heme ferryl intermediate. The overall energy profile indicates an energy barrier of approximately 18 kcal/mol and an exothermic driving force of almost 80 kcal/mol.
Collapse
Affiliation(s)
- Victor Guallar
- Life Science Department, Barcelona Supercomputing Center, Jordi Girona, 29, 08034 Barcelona, Spain.
| | | |
Collapse
|
46
|
Lu C, Zhao X, Lu Y, Rousseau DL, Yeh SR. Role of copper ion in regulating ligand binding in a myoglobin-based cytochrome C oxidase model. J Am Chem Soc 2010; 132:1598-605. [PMID: 20070118 DOI: 10.1021/ja907777f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cytochrome c oxidase (CcO), the terminal enzyme in the mitochondrial respiratory chain, catalyzes the four-electron reduction of dioxygen to water in a binuclear center comprised of a high-spin heme (heme a(3)) and a copper atom (Cu(B)) coordinated by three histidine residues. As a minimum model for CcO, a mutant of sperm whale myoglobin, named Cu(B)Mb, has been engineered, in which a copper atom is held in the distal heme pocket by the native E7 histidine and two nonnative histidine residues. In this work, the role of the copper in regulating ligand binding in Cu(B)Mb was investigated. Resonance Raman studies show that the presence of copper in CO-bound Cu(B)Mb leads to a CcO-like distal heme pocket. Stopped-flow data show that, upon the initiation of the CO binding reaction, the ligand first binds to the Cu(+); it subsequently transfers from Cu(+) to Fe(2+) in an intramolecular process, similar to that reported for CcO. The high CO affinity toward Cu(+) and the slow intramolecular CO transfer rate between Cu(+) and Fe(2+) in the Cu(B)Mb/Cu(+) complex are analogous to those in Thermus thermophilus CcO (TtCcO) but distinct from those in bovine CcO (bCcO). Additional kinetic studies show that, upon photolysis of the NO-bound Cu(B)Mb/Cu(+) complex, the photolyzed ligand transiently binds to Cu(+) and subsequently rebinds to Fe(2+), accounting for the 100% geminate recombination yield, similar to that found in TtCcO. The data demonstrate that the Cu(B)Mb/Cu(+) complex reproduces essential structural and kinetic features of CcO and that the complex is more akin to TtCcO than to bCcO.
Collapse
Affiliation(s)
- Changyuan Lu
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | | | | | | | | |
Collapse
|
47
|
Nickel E, Nienhaus K, Lu C, Yeh SR, Nienhaus GU. Ligand and substrate migration in human indoleamine 2,3-dioxygenase. J Biol Chem 2009; 284:31548-54. [PMID: 19767648 DOI: 10.1074/jbc.m109.039859] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human indoleamine 2,3-dioxygenase (hIDO), a monomeric heme enzyme, catalyzes the oxidative degradation of L-Trp and other indoleamine derivatives. Using Fourier transform infrared and optical absorption spectroscopy, we have investigated the interplay between ferrous hIDO, the ligand analog CO, and the physiological substrate L-Trp. These data provide the long sought evidence for two distinct L-Trp binding sites. Upon photodissociation from the heme iron at T > 200 K, CO escapes into the solvent. Concomitantly, L-Trp exits the active site and, depending on the l-Trp concentration, migrates to a secondary binding site or into the solvent. Although L-Trp is spectroscopically silent at this site, it is still noticeable due to its pronounced effect on the CO association kinetics, which are significantly slower than those of L-Trp-free hIDO. L-Trp returns to its initial site only after CO has rebound to the heme iron.
Collapse
Affiliation(s)
- Elena Nickel
- Institute of Biophysics, University of Ulm, 89069 Ulm, Germany
| | | | | | | | | |
Collapse
|
48
|
Borrelli KW, Cossins B, Guallar V. Exploring hierarchical refinement techniques for induced fit docking with protein and ligand flexibility. J Comput Chem 2009; 31:1224-35. [DOI: 10.1002/jcc.21409] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|