1
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Zlobin A, Smirnov I, Golovin A. Dynamic interchange between two protonation states is characteristic of active sites of cholinesterases. Protein Sci 2024; 33:e5100. [PMID: 39022909 PMCID: PMC11255601 DOI: 10.1002/pro.5100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 05/28/2024] [Accepted: 06/19/2024] [Indexed: 07/20/2024]
Abstract
Cholinesterases are well-known and widely studied enzymes crucial to human health and involved in neurology, Alzheimer's, and lipid metabolism. The protonation pattern of active sites of cholinesterases influences all the chemical processes within, including reaction, covalent inhibition by nerve agents, and reactivation. Despite its significance, our comprehension of the fine structure of cholinesterases remains limited. In this study, we employed enhanced-sampling quantum-mechanical/molecular-mechanical calculations to show that cholinesterases predominantly operate as dynamic mixtures of two protonation states. The proton transfer between two non-catalytic glutamate residues follows the Grotthuss mechanism facilitated by a mediator water molecule. We show that this uncovered complexity of active sites presents a challenge for classical molecular dynamics simulations and calls for special treatment. The calculated proton transfer barrier of 1.65 kcal/mol initiates a discussion on the potential existence of two coupled low-barrier hydrogen bonds in the inhibited form of butyrylcholinesterase. These findings expand our understanding of structural features expressed by highly evolved enzymes and guide future advances in cholinesterase-related protein and drug design studies.
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Affiliation(s)
- Alexander Zlobin
- Institute for Drug DiscoveryLeipzig University Medical SchoolLeipzigGermany
- Faculty of Bioengineering and BioinformaticsLomonosov Moscow State UniversityMoscowRussia
| | - Ivan Smirnov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscowRussia
| | - Andrey Golovin
- Faculty of Bioengineering and BioinformaticsLomonosov Moscow State UniversityMoscowRussia
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscowRussia
- Belozersky Institute of Physico‐Chemical BiologyLomonosov Moscow State UniversityMoscowRussia
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2
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Shelley KL, Garman EF. Quantifying and comparing radiation damage in the Protein Data Bank. Nat Commun 2022; 13:1314. [PMID: 35288575 PMCID: PMC8921271 DOI: 10.1038/s41467-022-28934-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 02/18/2022] [Indexed: 11/09/2022] Open
Abstract
Radiation damage remains one of the major bottlenecks to accurate structure solution in protein crystallography. It can induce structural and chemical changes in protein crystals, and is hence an important consideration when assessing the quality and biological veracity of crystal structures in repositories like the Protein Data Bank (PDB). However, detection of radiation damage artefacts has traditionally proved very challenging. To address this, here we introduce the Bnet metric. Bnet summarises in a single value the extent of damage suffered by a crystal structure by comparing the B-factor values of damage-prone and non-damage-prone atoms in a similar local environment. After validating that Bnet successfully detects damage in 23 different crystal structures previously characterised as damaged, we calculate Bnet values for 93,978 PDB crystal structures. Our metric highlights a range of damage features, many of which would remain unidentified by the other summary statistics typically calculated for PDB structures.
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Affiliation(s)
- Kathryn L Shelley
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom.
| | - Elspeth F Garman
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.
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3
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Caldararu O, Ekberg V, Logan DT, Oksanen E, Ryde U. Exploring ligand dynamics in protein crystal structures with ensemble refinement. Acta Crystallogr D Struct Biol 2021; 77:1099-1115. [PMID: 34342282 PMCID: PMC8329865 DOI: 10.1107/s2059798321006513] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/21/2021] [Indexed: 11/10/2022] Open
Abstract
Understanding the dynamics of ligands bound to proteins is an important task in medicinal chemistry and drug design. However, the dominant technique for determining protein-ligand structures, X-ray crystallography, does not fully account for dynamics and cannot accurately describe the movements of ligands in protein binding sites. In this article, an alternative method, ensemble refinement, is used on six protein-ligand complexes with the aim of understanding the conformational diversity of ligands in protein crystal structures. The results show that ensemble refinement sometimes indicates that the flexibility of parts of the ligand and some protein side chains is larger than that which can be described by a single conformation and atomic displacement parameters. However, since the electron-density maps are comparable and Rfree values are slightly increased, the original crystal structure is still a better model from a statistical point of view. On the other hand, it is shown that molecular-dynamics simulations and automatic generation of alternative conformations in crystallographic refinement confirm that the flexibility of these groups is larger than is observed in standard refinement. Moreover, the flexible groups in ensemble refinement coincide with groups that give high atomic displacement parameters or non-unity occupancy if optimized in standard refinement. Therefore, the conformational diversity indicated by ensemble refinement seems to be qualitatively correct, indicating that ensemble refinement can be an important complement to standard crystallographic refinement as a tool to discover which parts of crystal structures may show extensive flexibility and therefore are poorly described by a single conformation. However, the diversity of the ensembles is often exaggerated (probably partly owing to the rather poor force field employed) and the ensembles should not be trusted in detail.
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Affiliation(s)
- Octav Caldararu
- Department of Theoretical Chemistry, Lund University, Chemical Centre, PO Box 124, SE-221 00 Lund, Sweden
| | - Vilhelm Ekberg
- Department of Theoretical Chemistry, Lund University, Chemical Centre, PO Box 124, SE-221 00 Lund, Sweden
| | - Derek T. Logan
- Biochemistry and Structural Biology, Centre for Molecular Protein Science, Department of Chemistry, Lund University, Chemical Centre, PO Box 124, SE-221 00 Lund, Sweden
| | - Esko Oksanen
- European Spallation Source Consortium ESS ERIC, PO Box 176, SE-221 00 Lund, Sweden
| | - Ulf Ryde
- Department of Theoretical Chemistry, Lund University, Chemical Centre, PO Box 124, SE-221 00 Lund, Sweden
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4
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Godoy R, Machuca J, Venthur H, Quiroz A, Mutis A. An Overview of Antennal Esterases in Lepidoptera. Front Physiol 2021; 12:643281. [PMID: 33868009 PMCID: PMC8044547 DOI: 10.3389/fphys.2021.643281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 03/15/2021] [Indexed: 12/02/2022] Open
Abstract
Lepidoptera are used as a model for the study of insect olfactory proteins. Among them, odorant degrading enzymes (ODEs), that degrade odorant molecules to maintain the sensitivity of antennae, have received less attention. In particular, antennal esterases (AEs; responsible for ester degradation) are crucial for intraspecific communication in Lepidoptera. Currently, transcriptomic and genomic studies have provided AEs in several species. However, efforts in gene annotation, classification, and functional assignment are still lacking. Therefore, we propose to combine evidence at evolutionary, structural, and functional level to update ODEs as well as key information into an easier classification, particularly of AEs. Finally, the kinetic parameters for putative inhibition of ODEs are discussed in terms of its role in future integrated pest management (IPM) strategies.
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Affiliation(s)
- Ricardo Godoy
- Programa de Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Temuco, Chile
- Centro de Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Temuco, Chile
| | - Juan Machuca
- Programa de Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Temuco, Chile
- Centro de Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Temuco, Chile
| | - Herbert Venthur
- Centro de Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Temuco, Chile
| | - Andrés Quiroz
- Centro de Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Temuco, Chile
| | - Ana Mutis
- Centro de Investigación Biotecnológica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Temuco, Chile
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5
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Overcoming insecticide resistance through computational inhibitor design. Proc Natl Acad Sci U S A 2019; 116:21012-21021. [PMID: 31575743 DOI: 10.1073/pnas.1909130116] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Insecticides allow control of agricultural pests and disease vectors and are vital for global food security and health. The evolution of resistance to insecticides, such as organophosphates (OPs), is a serious and growing concern. OP resistance often involves sequestration or hydrolysis of OPs by carboxylesterases. Inhibiting carboxylesterases could, therefore, restore the effectiveness of OPs for which resistance has evolved. Here, we use covalent virtual screening to produce nano-/picomolar boronic acid inhibitors of the carboxylesterase αE7 from the agricultural pest Lucilia cuprina as well as a common Gly137Asp αE7 mutant that confers OP resistance. These inhibitors, with high selectivity against human acetylcholinesterase and low to no toxicity in human cells and in mice, act synergistically with the OPs diazinon and malathion to reduce the amount of OP required to kill L. cuprina by up to 16-fold and abolish resistance. The compounds exhibit broad utility in significantly potentiating another OP, chlorpyrifos, against the common pest, the peach-potato aphid (Myzus persicae). These compounds represent a solution to OP resistance as well as to environmental concerns regarding overuse of OPs, allowing significant reduction of use without compromising efficacy.
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6
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Hopkins DH, Rane RV, Younus F, Coppin CW, Pandey G, Jackson CJ, Oakeshott JG. The molecular basis for the neofunctionalization of the juvenile hormone esterase duplication in Drosophila. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 106:10-18. [PMID: 30611903 DOI: 10.1016/j.ibmb.2019.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/01/2019] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
The Drosophila melanogaster enzymes juvenile hormone esterase (DmJHE) and its duplicate, DmJHEdup, present ideal examples for studying the structural changes involved in the neofunctionalization of enzyme duplicates. DmJHE is a hormone esterase with precise regulation and highly specific activity for its substrate, juvenile hormone. DmJHEdup is an odorant degrading esterase (ODE) responsible for processing various kairomones in antennae. Our phylogenetic analysis shows that the JHE lineage predates the hemi/holometabolan split and that several duplications of JHEs have been templates for the evolution of secreted β-esterases such as ODEs through the course of insect evolution. Our biochemical comparisons further show that DmJHE has sufficient substrate promiscuity and activity against odorant esters for a duplicate to evolve a general ODE function against a range of mid-long chain food esters, as is shown in DmJHEdup. This substrate range complements that of the only other general ODE known in this species, Esterase 6. Homology models of DmJHE and DmJHEdup enabled comparisons between each enzyme and the known structures of a lepidopteran JHE and Esterase 6. Both JHEs showed very similar active sites despite low sequence identity (30%). Both ODEs differed drastically from the JHEs and each other, explaining their complementary substrate ranges. A small number of amino acid changes are identified that may have been involved in the early stages of the neofunctionalization of DmJHEdup. Our results provide key insights into the process of neofunctionalization and the structural changes that can be involved.
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Affiliation(s)
- Davis H Hopkins
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, 2601, Australia; CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia.
| | - Rahul V Rane
- CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia
| | - Faisal Younus
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, 2601, Australia; CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia
| | - Chris W Coppin
- CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia
| | - Gunjan Pandey
- CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - John G Oakeshott
- CSIRO Land and Water, Black Mountain, Canberra, Australian Capital Territory, 2601, Australia
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7
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Wei P, Li J, Liu X, Nan C, Shi L, Zhang Y, Li C, He L. Functional analysis of four upregulated carboxylesterase genes associated with fenpropathrin resistance in Tetranychus cinnabarinus (Boisduval). PEST MANAGEMENT SCIENCE 2019; 75:252-261. [PMID: 29877064 DOI: 10.1002/ps.5109] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 05/25/2018] [Accepted: 05/28/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Carboxylesterases (CarEs) are important in pesticide resistance. Four overexpressed CarE genes with inducible character were screened out in fenpropathrin-resistant Tetranychus cinnabarinus, but their functional roles remained to be further analyzed by RNAi and protein expression. RESULTS Feeding a single double-stranded (ds)RNA of each of four genes led to gene-specific downregulation of mRNA, decreased esterase activity and diminished resistance in T. cinnabarinus. More interestingly, feeding four dsRNAs simultaneously led to a more significant decrease in enzymatic activity and fold resistance than feeding a single dsRNA individually, suggesting that these CarE genes were involved in fenpropathrin-resistance and had cooperative roles. The gene CarE6 was regarded as the primary and representative candidate to be functionally expressed, because silencing of CarE6 led to the most significant decrease in resistance level. The activity of CarE6 protein was competitively inhibited by fenpropathrin. It could effectively decompose 41.7 ± 0.09% of fenpropathrin within 3 h, proving that CarE6 protein was capable of metabolizing fenpropathrin effectively in T. cinnabarinus. CONCLUSION The results confirm that four CarE genes are cooperatively involved in fenpropathrin resistance and the metabolic enzymes encoded by these overexpressed genes do indeed metabolize acaricide in resistant T. cinnabarinus in the evolution of acaricide resistance. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Peng Wei
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Jinhang Li
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Xinyang Liu
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Can Nan
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Li Shi
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
- College of Plant Protection, Hunan Agricultural University, Hunan Province, China
| | - Yichao Zhang
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Chuanzhen Li
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
| | - Lin He
- Academy of Agricultural Sciences, Southwest University; College of Plant Protection, Southwest University, Chongqing, China
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8
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Buckle AM, Borg NA. Integrating Experiment and Theory to Understand TCR-pMHC Dynamics. Front Immunol 2018; 9:2898. [PMID: 30581442 PMCID: PMC6293202 DOI: 10.3389/fimmu.2018.02898] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/26/2018] [Indexed: 11/13/2022] Open
Abstract
The conformational dynamism of proteins is well established. Rather than having a single structure, proteins are more accurately described as a conformational ensemble that exists across a rugged energy landscape, where different conformational sub-states interconvert. The interaction between αβ T cell receptors (TCR) and cognate peptide-MHC (pMHC) is no exception, and is a dynamic process that involves substantial conformational change. This review focuses on technological advances that have begun to establish the role of conformational dynamics and dynamic allostery in TCR recognition of the pMHC and the early stages of signaling. We discuss how the marriage of molecular dynamics (MD) simulations with experimental techniques provides us with new ways to dissect and interpret the process of TCR ligation. Notably, application of simulation techniques lags behind other fields, but is predicted to make substantial contributions. Finally, we highlight integrated approaches that are being used to shed light on some of the key outstanding questions in the early events leading to TCR signaling.
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Affiliation(s)
- Ashley M Buckle
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Natalie A Borg
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
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9
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Dehouck Y, Bastolla U. The maximum penalty criterion for ridge regression: application to the calibration of the force constant in elastic network models. Integr Biol (Camb) 2018; 9:627-641. [PMID: 28555214 DOI: 10.1039/c7ib00079k] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Tikhonov regularization, or ridge regression, is a popular technique to deal with collinearity in multivariate regression. We unveil a formal analogy between ridge regression and statistical mechanics, where the objective function is comparable to a free energy, and the ridge parameter plays the role of temperature. This analogy suggests two novel criteria for selecting a suitable ridge parameter: specific-heat (Cv) and maximum penalty (MP). We apply these fits to evaluate the relative contributions of rigid-body and internal fluctuations, which are typically highly collinear, to crystallographic B-factors. This issue is particularly important for computational models of protein dynamics, such as the elastic network model (ENM), since the amplitude of the predicted internal motion is commonly calibrated using B-factor data. After validation on simulated datasets, our results indicate that rigid-body motions account on average for more than 80% of the amplitude of B-factors. Furthermore, we evaluate the ability of different fits to reproduce the amplitudes of internal fluctuations in X-ray ensembles from the B-factors in the corresponding single X-ray structures. The new ridge criteria are shown to be markedly superior to the commonly used two-parameter fit that neglects rigid-body rotations and to the full fits regularized under generalized cross-validation. In conclusion, the proposed fits ensure a more robust calibration of the ENM force constant and should prove valuable in other applications.
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Affiliation(s)
- Yves Dehouck
- Machine Learning Group, Université Libre de Bruxelles (ULB), Boulevard du Triomphe CP 212, 1050 Brussels, Belgium.
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10
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Fodor J, Riley BT, Borg NA, Buckle AM. Previously Hidden Dynamics at the TCR-Peptide-MHC Interface Revealed. THE JOURNAL OF IMMUNOLOGY 2018; 200:4134-4145. [PMID: 29728507 DOI: 10.4049/jimmunol.1800315] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 04/10/2018] [Indexed: 12/28/2022]
Abstract
A structural characterization of the interaction between αβ TCRs and cognate peptide-MHC (pMHC) is central to understanding adaptive T cell-mediated immunity. X-ray crystallography, although the source of much structural data, traditionally provides only a static snapshot of the protein. Given the emerging evidence for the important role of conformational dynamics in protein function, we interrogated 309 crystallographic structures of pMHC complexes using ensemble refinement, a technique that can extract dynamic information from the x-ray data. Focusing on a subset of human pMHC class I systems, we found that in many cases, ensemble methods were able to uncover previously hidden evidence of significant conformational plasticity, thereby revealing additional information that can build upon and significantly enhance functional interpretations that are based on a single static structure. Notable examples include the interpretation of differences in the disease association of HLA subtypes, the relationship between peptide prominence and TCR recognition, the role of conformational flexibility in vaccine design, and the discrimination between induced fit and conformational selection models of TCR binding. We show that the currently widespread practice of analyzing pMHC interactions via the study of a single crystallographic structure does not make use of pertinent and easily accessible information from x-ray data concerning alternative protein conformations. This new analysis therefore not only highlights the capacity for ensemble methods to significantly enrich the interpretation of decades of structural data but also provides previously missing information concerning the dynamics of existing characterized TCR-pMHC interactions.
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Affiliation(s)
- James Fodor
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Blake T Riley
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Natalie A Borg
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Ashley M Buckle
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
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11
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Gong YH, Ai GM, Li M, Shi XY, Diao QY, Gao XW. Functional characterization of carboxylesterase gene mutations involved in Aphis gossypii resistance to organophosphate insecticides. INSECT MOLECULAR BIOLOGY 2017; 26:702-714. [PMID: 28799241 DOI: 10.1111/imb.12331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Carboxylesterases (CarEs) play an important role in detoxifying insecticides in insects. Over-expression and structural modification of CarEs have been implicated in the development of organophosphate (OP) insecticide resistance in insects. A previous study identified four nonsynonymous mutations (resulting in four amino acid residue substitutions) in the open reading frame of the carboxylesterase gene of resistant cotton aphids compared to the omethoate susceptible strain, which has possibly influenced the development of resistance to omethoate (a systemic OP insecticide). The current study further characterized the function of these mutations, both alone and in combination, in the hydrolysis of OP insecticides. The metabolism results suggest that the combination of four mutations, mainly existing in the laboratory-selected OP-resistant cotton aphid population, increased the OP hydrolase activity (approximately twofold) at the cost of detectable carboxylesterase activity. The functional studies of single or multiple mutations suggest the positive effect of H104R, A128V and T333P on the acquisition of OP hydrolase activity, especially the combination of H104R with A128V or T333P. K484R substitution decreased both the OP hydrolase activity and the CarE activity, indicating that this mutation primarily drives the negative effect on the acquisition of OP hydrolase activity amongst these four mutations in the resistant strain. The modelling and docking results are basically consistent with the metabolic results, which strongly suggest that the structural gene modification is the molecular basis for the OP resistance in this laboratory-selected cotton aphid strain.
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Affiliation(s)
- Y-H Gong
- Department of Entomology, China Agricultural University, Beijing, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - G-M Ai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - M Li
- University of California, Riverside, CA, USA
| | - X-Y Shi
- Department of Entomology, China Agricultural University, Beijing, China
| | - Q-Y Diao
- Department of Honeybee Protection and Biosafety, Institute of Apicultural Research, Chinese Academy of Agricultural Science, Beijing, China
| | - X-W Gao
- Department of Entomology, China Agricultural University, Beijing, China
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12
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Budday D, Fonseca R, Leyendecker S, van den Bedem H. Frustration-guided motion planning reveals conformational transitions in proteins. Proteins 2017; 85:1795-1807. [DOI: 10.1002/prot.25333] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 05/19/2017] [Accepted: 06/07/2017] [Indexed: 01/27/2023]
Affiliation(s)
- Dominik Budday
- Chair of Applied Dynamics, University of Erlangen-Nuremberg; Erlangen Germany
| | - Rasmus Fonseca
- Department of Molecular and Cellular Physiology; Stanford University; California Menlo Park
- Biosciences Division; SLAC National Accelerator Laboratory, Stanford University; California Menlo Park
| | - Sigrid Leyendecker
- Chair of Applied Dynamics, University of Erlangen-Nuremberg; Erlangen Germany
| | - Henry van den Bedem
- Biosciences Division; SLAC National Accelerator Laboratory, Stanford University; California Menlo Park
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13
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Palamini M, Canciani A, Forneris F. Identifying and Visualizing Macromolecular Flexibility in Structural Biology. Front Mol Biosci 2016; 3:47. [PMID: 27668215 PMCID: PMC5016524 DOI: 10.3389/fmolb.2016.00047] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/22/2016] [Indexed: 12/29/2022] Open
Abstract
Structural biology comprises a variety of tools to obtain atomic resolution data for the investigation of macromolecules. Conventional structural methodologies including crystallography, NMR and electron microscopy often do not provide sufficient details concerning flexibility and dynamics, even though these aspects are critical for the physiological functions of the systems under investigation. However, the increasing complexity of the molecules studied by structural biology (including large macromolecular assemblies, integral membrane proteins, intrinsically disordered systems, and folding intermediates) continuously demands in-depth analyses of the roles of flexibility and conformational specificity involved in interactions with ligands and inhibitors. The intrinsic difficulties in capturing often subtle but critical molecular motions in biological systems have restrained the investigation of flexible molecules into a small niche of structural biology. Introduction of massive technological developments over the recent years, which include time-resolved studies, solution X-ray scattering, and new detectors for cryo-electron microscopy, have pushed the limits of structural investigation of flexible systems far beyond traditional approaches of NMR analysis. By integrating these modern methods with powerful biophysical and computational approaches such as generation of ensembles of molecular models and selective particle picking in electron microscopy, more feasible investigations of dynamic systems are now possible. Using some prominent examples from recent literature, we review how current structural biology methods can contribute useful data to accurately visualize flexibility in macromolecular structures and understand its important roles in regulation of biological processes.
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Affiliation(s)
| | | | - Federico Forneris
- The Armenise-Harvard Laboratory of Structural Biology, Department of Biology and Biotechnology, University of PaviaPavia, Italy
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