1
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Leitl KD, Sperl LE, Hagn F. Preferred inhibition of pro-apoptotic Bak by BclxL via a two-step mechanism. Cell Rep 2024; 43:114526. [PMID: 39046879 DOI: 10.1016/j.celrep.2024.114526] [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: 02/27/2024] [Revised: 06/14/2024] [Accepted: 07/08/2024] [Indexed: 07/27/2024] Open
Abstract
Bak is a pore-forming Bcl2 protein that induces apoptosis at the outer mitochondrial membrane, which can either proceed via Bak oligomerization or be inhibited by anti-apoptotic Bcl2 proteins, such as BclxL. BclxL is very efficient in inhibiting Bak pore formation, but the mechanistic basis of this preferred interaction has remained enigmatic. Here, we identify Bakα1 as a second binding site for BclxL and show that it specifically interacts with the Bcl2-homology (BH)3 binding groove of BclxL. The affinity between BclxL and Bakα1 is weaker than with Bak-BH3, suggesting that Bakα1, being exposed early in the pore-forming trajectory, transiently captures BclxL, which subsequently transitions to the proximal BH3 site. Bak variants where the initial transient interaction with BclxL is modulated show a markedly altered response to BclxL inhibition. This work contributes to a better mechanistic understanding of the fine-tuned interactions between different players of the Bcl2 protein family.
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Affiliation(s)
- Kira D Leitl
- Bavarian NMR Center (BNMRZ), Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany; Molecular Targets and Therapeutics Center (MTTC), Institute of Structural Biology, Helmholtz Munich, 85764 Neuherberg, Germany
| | - Laura E Sperl
- Bavarian NMR Center (BNMRZ), Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany
| | - Franz Hagn
- Bavarian NMR Center (BNMRZ), Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany; Molecular Targets and Therapeutics Center (MTTC), Institute of Structural Biology, Helmholtz Munich, 85764 Neuherberg, Germany.
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2
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Liu J, Nam Y, Choi D, Choi Y, Lee SE, Oh H, Wang G, Lee SH, Liu Y, Hong S. MXene/Hydrogel-based bioelectronic nose for the direct evaluation of food spoilage in both liquid and gas-phase environments. Biosens Bioelectron 2024; 256:116260. [PMID: 38613935 DOI: 10.1016/j.bios.2024.116260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/22/2024] [Accepted: 03/28/2024] [Indexed: 04/15/2024]
Abstract
Various bioelectronic noses have been recently developed for mimicking human olfactory systems. However, achieving direct monitoring of gas-phase molecules remains a challenge for the development of bioelectronic noses due to the instability of receptor and the limitations of its surrounding microenvironment. Here, we report a MXene/hydrogel-based bioelectronic nose for the sensitive detection of liquid and gaseous hexanal, a signature odorant from spoiled food. In this study, a conducting MXene/hydrogel structure was formed on a sensor via physical adsorption. Then, canine olfactory receptor 5269-embedded nanodiscs (cfOR5269NDs) which could selectively recognize hexanal molecules were embedded in the three-dimensional (3D) MXene/hydrogel structures using glutaraldehyde as a linker. Our MXene/hydrogel-based bioelectronic nose exhibited a high selectivity and sensitivity for monitoring hexanal in both liquid and gas phases. The bioelectronic noses could sensitively detect liquid and gaseous hexanal down to 10-18 M and 6.9 ppm, and they had wide detection ranges of 10-18 - 10-6 M and 6.9-32.9 ppm, respectively. Moreover, our bioelectronic nose allowed us to monitor hexanal levels in fish and milk. In this respect, our MXene/hydrogel-based bioelectronic nose could be a practical strategy for versatile applications such as food spoilage assessments in both liquid and gaseous systems.
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Affiliation(s)
- Jing Liu
- School of Food Science and Engineering, Ningxia University, Yinchuan, 750021, China
| | - Youngju Nam
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, 15588, Republic of Korea
| | - Danmin Choi
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yoonji Choi
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sang-Eun Lee
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Honggyu Oh
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, 15588, Republic of Korea
| | - Guangxian Wang
- School of Food Science and Engineering, Ningxia University, Yinchuan, 750021, China
| | - Seung Hwan Lee
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, 15588, Republic of Korea.
| | - Yuan Liu
- Department of Food Science & Technology, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Seunghun Hong
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea.
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3
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Baskakova KO, Kuzmichev PK, Karbyshev MS. Advanced applications of Nanodiscs-based platforms for antibodies discovery. Biophys Chem 2024; 313:107290. [PMID: 39002246 DOI: 10.1016/j.bpc.2024.107290] [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: 03/31/2024] [Revised: 06/18/2024] [Accepted: 07/08/2024] [Indexed: 07/15/2024]
Abstract
Due to their fundamental biological importance, membrane proteins (MPs) are attractive targets for drug discovery, with cell surface receptors, transporters, ion channels, and membrane-bound enzymes being of particular interest. However, due to numerous challenges, these proteins present underutilized opportunities for discovering biotherapeutics. Antibodies hold the promise of exquisite specificity and adaptability, making them the ideal candidates for targeting complex membrane proteins. They can target specific conformations of a particular membrane protein and can be engineered into various formats. Generating specific and effective antibodies targeting these proteins is no easy task due to several factors. The antigen's design, antibody-generation strategies, lead optimization technologies, and antibody modalities can be modified to tackle these challenges. The rational employment of cutting-edge lipid nanoparticle systems for retrieving the membrane antigen has been successfully implemented to simplify the mechanism-based therapeutic antibody discovery approach. Despite the highlighted MP production challenges, this review unequivocally underscores the advantages of targeting complex membrane proteins with antibodies and designing membrane protein antigens. Selected examples of lipid nanoparticle success have been illustrated, emphasizing the potential of therapeutic antibody discovery in this regard. With further research and development, we can overcome these challenges and unlock the full potential of therapeutic antibodies directed to target complex MPs.
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Affiliation(s)
- Kristina O Baskakova
- Laboratory of Molecular Therapy of Cancer, Cancer Research Institute, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russian Federation
| | - Pavel K Kuzmichev
- Research Сenter for Molecular Mechanisms of Aging and Age-related Diseases, Moscow Institute of Physics and Technology, Dolgoprudniy, Russian Federation
| | - Mikhail S Karbyshev
- Laboratory of Molecular Therapy of Cancer, Cancer Research Institute, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russian Federation; Department of Biochemistry and Molecular Biology, Pirogov Russian National Research Medical University, Moscow, Russian Federation.
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4
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Daniilidis M, Sperl LE, Müller BS, Babl A, Hagn F. Efficient Segmental Isotope Labeling of Integral Membrane Proteins for High-Resolution NMR Studies. J Am Chem Soc 2024; 146:15403-15410. [PMID: 38787792 PMCID: PMC11157531 DOI: 10.1021/jacs.4c03294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024]
Abstract
High-resolution structural NMR analyses of membrane proteins are challenging due to their large size, resulting in broad resonances and strong signal overlap. Among the isotope labeling methods that can remedy this situation, segmental isotope labeling is a suitable strategy to simplify NMR spectra and retain high-resolution structural information. However, protein ligation within integral membrane proteins is complicated since the hydrophobic protein fragments are insoluble, and the removal of ligation side-products is elaborate. Here, we show that a stabilized split-intein system can be used for rapid and high-yield protein trans-splicing of integral membrane proteins under denaturing conditions. This setup enables segmental isotope labeling experiments within folded protein domains for NMR studies. We show that high-quality NMR spectra of markedly reduced complexity can be obtained in detergent micelles and lipid nanodiscs. Of note, the nanodisc insertion step specifically selects for the ligated and correctly folded membrane protein and simultaneously removes ligation byproducts. Using this tailored workflow, we show that high-resolution NMR structure determination is strongly facilitated with just two segmentally isotope-labeled membrane protein samples. The presented method will be broadly applicable to structural and dynamical investigations of (membrane-) proteins and their complexes by solution and solid-state NMR but also other structural methods where segmental labeling is beneficial.
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Affiliation(s)
- Melina Daniilidis
- Bavarian
NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85748 Garching, Germany
| | - Laura E. Sperl
- Bavarian
NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85748 Garching, Germany
| | - Benedikt S. Müller
- Bavarian
NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85748 Garching, Germany
| | - Antonia Babl
- Bavarian
NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85748 Garching, Germany
| | - Franz Hagn
- Bavarian
NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85748 Garching, Germany
- Institute
of Structural Biology, Helmholtz Munich, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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5
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The Advanced Properties of Circularized MSP Nanodiscs Facilitate High-resolution NMR Studies of Membrane Proteins. J Mol Biol 2022; 434:167861. [PMID: 36273602 DOI: 10.1016/j.jmb.2022.167861] [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: 08/01/2022] [Revised: 10/12/2022] [Accepted: 10/16/2022] [Indexed: 11/06/2022]
Abstract
Membrane mimetics are essential for structural and functional studies of membrane proteins. A promising lipid-based system are phospholipid nanodiscs, where two copies of a so-called membrane scaffold protein (MSP) wrap around a patch of lipid bilayer. Consequently, the size of a nanodisc is determined by the length of the MSP. Furthermore, covalent MSP circularization was reported to improve nanodisc stability. However, a more detailed comparative analysis of the biophysical properties of circularized and linear MSP nanodiscs for their use in high-resolution NMR has not been conducted so far. Here, we analyze the membrane fluidity and temperature-dependent size variability of circularized and linear nanodiscs using a large set of analytical methods. We show that MSP circularization does not alter the membrane fluidity in nanodiscs. Further, we show that the phase transition temperature increases for circularized versions, while the cooperativity decreases. We demonstrate that circularized nanodiscs keep a constant size over a large temperature range, in contrast to their linear MSP counterparts. Due to this size stability, circularized nanodiscs are beneficial for high-resolution NMR studies of membrane proteins at elevated temperatures. Despite their slightly larger size as compared to linear nanodiscs, 3D NMR experiments of the voltage-dependent anion channel 1 (VDAC1) in circularized nanodiscs have a markedly improved spectral quality in comparison to VDAC1 incorporated into linear nanodiscs of a similar size. This study provides evidence that circularized MSP nanodiscs are a promising tool to facilitate high-resolution NMR studies of larger and challenging membrane proteins in a native lipid environment.
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6
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Krishnarjuna B, Ramamoorthy A. Detergent-Free Isolation of Membrane Proteins and Strategies to Study Them in a Near-Native Membrane Environment. Biomolecules 2022; 12:1076. [PMID: 36008970 PMCID: PMC9406181 DOI: 10.3390/biom12081076] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 07/31/2022] [Accepted: 08/02/2022] [Indexed: 02/06/2023] Open
Abstract
Atomic-resolution structural studies of membrane-associated proteins and peptides in a membrane environment are important to fully understand their biological function and the roles played by them in the pathology of many diseases. However, the complexity of the cell membrane has severely limited the application of commonly used biophysical and biochemical techniques. Recent advancements in NMR spectroscopy and cryoEM approaches and the development of novel membrane mimetics have overcome some of the major challenges in this area. For example, the development of a variety of lipid-nanodiscs has enabled stable reconstitution and structural and functional studies of membrane proteins. In particular, the ability of synthetic amphipathic polymers to isolate membrane proteins directly from the cell membrane, along with the associated membrane components such as lipids, without the use of a detergent, has opened new avenues to study the structure and function of membrane proteins using a variety of biophysical and biological approaches. This review article is focused on covering the various polymers and approaches developed and their applications for the functional reconstitution and structural investigation of membrane proteins. The unique advantages and limitations of the use of synthetic polymers are also discussed.
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Affiliation(s)
- Bankala Krishnarjuna
- Department of Chemistry and Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry and Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
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7
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Tanriver G, Monard G, Catak S. Impact of Deamidation on the Structure and Function of Antiapoptotic Bcl-x L. J Chem Inf Model 2021; 62:102-115. [PMID: 34942070 DOI: 10.1021/acs.jcim.1c00808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bcl-xL is an antiapoptotic mitochondrial trans-membrane protein, which is known to play a crucial role in the survival of tumor cells. The deamidation of Bcl-xL is a pivotal switch that regulates its biological function. The potential impact of deamidation on the structure and dynamics of Bcl-xL is directly linked to the intrinsically disordered region (IDR), which is the main site for post-translational modifications (PTMs). In this study, we explored deamidation-induced conformational changes in Bcl-xL to gain insight into its loss of function by performing microsecond-long molecular dynamics (MD) simulations. MD simulation outcomes showed that the IDR motion and interaction patterns have changed notably upon deamidation. Principal component analysis (PCA) demonstrates significant differences between wild-type and deamidated Bcl-xL and suggests that deamidation affects the structure and dynamics of Bcl-xL. The combination of clustering analysis, H-bond analysis, and PCA revealed changes in conformation, interaction, and dynamics upon deamidation. Differences in contact patterns and essential dynamics that lead to a narrowing in the binding groove (BG) are clear indications of deamidation-induced allosteric effects. In line with previous studies, we show that the IDR plays a very important role in the loss of apoptotic functions of Bcl-xL while providing a unique perspective on the underlying mechanism of Bcl-xL deamidation-induced cell death.
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Affiliation(s)
- Gamze Tanriver
- Department of Chemistry, Bogazici University, Bebek, 34342 Istanbul, Turkey.,Université de Lorraine, LPCT UMR 7019 CNRS, Boulevard des Aiguillettes B.P. 70239, 54506 Vandœuvre-les-Nancy, France
| | - Gerald Monard
- Université de Lorraine, LPCT UMR 7019 CNRS, Boulevard des Aiguillettes B.P. 70239, 54506 Vandœuvre-les-Nancy, France
| | - Saron Catak
- Department of Chemistry, Bogazici University, Bebek, 34342 Istanbul, Turkey
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8
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Abstract
Membrane proteins (MPs) play essential roles in numerous cellular processes. Because around 70% of the currently marketed drugs target MPs, a detailed understanding of their structure, binding properties, and functional dynamics in a physiologically relevant environment is crucial for a more detailed understanding of this important protein class. We here summarize the benefits of using lipid nanodiscs for NMR structural investigations and provide a detailed overview of the currently used lipid nanodisc systems as well as their applications in solution-state NMR. Despite the increasing use of other structural methods for the structure determination of MPs in lipid nanodiscs, solution NMR turns out to be a versatile tool to probe a wide range of MP features, ranging from the structure determination of small to medium-sized MPs to probing ligand and partner protein binding as well as functionally relevant dynamical signatures in a lipid nanodisc setting. We will expand on these topics by discussing recent NMR studies with lipid nanodiscs and work out a key workflow for optimizing the nanodisc incorporation of an MP for subsequent NMR investigations. With this, we hope to provide a comprehensive background to enable an informed assessment of the applicability of lipid nanodiscs for NMR studies of a particular MP of interest.
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Affiliation(s)
- Umut Günsel
- Bavarian NMR Center (BNMRZ) at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Strasse 2, 85748 Garching, Germany
| | - Franz Hagn
- Bavarian NMR Center (BNMRZ) at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Strasse 2, 85748 Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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9
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Sperl LE, Rührnößl F, Schiller A, Haslbeck M, Hagn F. High-resolution analysis of the conformational transition of pro-apoptotic Bak at the lipid membrane. EMBO J 2021; 40:e107159. [PMID: 34523144 PMCID: PMC8521305 DOI: 10.15252/embj.2020107159] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 08/09/2021] [Accepted: 08/20/2021] [Indexed: 12/21/2022] Open
Abstract
Permeabilization of the outer mitochondrial membrane by pore-forming Bcl2 proteins is a crucial step for the induction of apoptosis. Despite a large set of data suggesting global conformational changes within pro-apoptotic Bak during pore formation, high-resolution structural details in a membrane environment remain sparse. Here, we used NMR and HDX-MS (Hydrogen deuterium exchange mass spectrometry) in lipid nanodiscs to gain important high-resolution structural insights into the conformational changes of Bak at the membrane that are dependent on a direct activation by BH3-only proteins. Furthermore, we determined the first high-resolution structure of the Bak transmembrane helix. Upon activation, α-helix 1 in the soluble domain of Bak dissociates from the protein and adopts an unfolded and dynamic potentially membrane-bound state. In line with this finding, comparative protein folding experiments with Bak and anti-apoptotic BclxL suggest that α-helix 1 in Bak is a metastable structural element contributing to its pro-apoptotic features. Consequently, mutagenesis experiments aimed at stabilizing α-helix 1 yielded Bak variants with delayed pore-forming activity. These insights will contribute to a better mechanistic understanding of Bak-mediated membrane permeabilization.
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Affiliation(s)
- Laura E Sperl
- Bavarian NMR Center at the Department of ChemistryTechnical University of MunichGarchingGermany
- Institute of Structural BiologyHelmholtz Zentrum MünchenNeuherbergGermany
| | - Florian Rührnößl
- Center for Functional Protein Assemblies and Department of ChemistryTechnical University of MunichGarchingGermany
| | - Anita Schiller
- Bavarian NMR Center at the Department of ChemistryTechnical University of MunichGarchingGermany
- Institute of Structural BiologyHelmholtz Zentrum MünchenNeuherbergGermany
| | - Martin Haslbeck
- Center for Functional Protein Assemblies and Department of ChemistryTechnical University of MunichGarchingGermany
| | - Franz Hagn
- Bavarian NMR Center at the Department of ChemistryTechnical University of MunichGarchingGermany
- Institute of Structural BiologyHelmholtz Zentrum MünchenNeuherbergGermany
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10
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Effects of Cardiolipin on the Conformational Dynamics of Membrane-Anchored Bcl-xL. Int J Mol Sci 2021; 22:ijms22179388. [PMID: 34502299 PMCID: PMC8431346 DOI: 10.3390/ijms22179388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/24/2021] [Accepted: 08/26/2021] [Indexed: 02/06/2023] Open
Abstract
The anti-apoptotic protein Bcl-xL regulates apoptosis by preventing the permeation of the mitochondrial outer membrane by pro-apoptotic pore-forming proteins, which release apoptotic factors into the cytosol that ultimately lead to cell death. Two different membrane-integrated Bcl-xL constructs have been identified: a membrane-anchored and a membrane-inserted conformation. Here, we use molecular dynamics simulations to study the effect of the mitochondrial specific lipid cardiolipin and the protein protonation state on the conformational dynamics of membrane-anchored Bcl-xL. The analysis reveals that the protonation state of the protein and cardiolipin content of the membrane modulate the orientation of the soluble head region (helices α1 through α7) and hence the exposure of its BH3-binding groove, which is required for its interaction with pro-apoptotic proteins.
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11
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Sora V, Sanchez D, Papaleo E. Bcl-xL Dynamics under the Lens of Protein Structure Networks. J Phys Chem B 2021; 125:4308-4320. [PMID: 33848145 DOI: 10.1021/acs.jpcb.0c11562] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Understanding the finely orchestrated interactions leading to or preventing programmed cell death (apoptosis) is of utmost importance in cancer research because the failure of these systems could eventually lead to the onset of the disease. In this regard, the maintenance of a delicate balance between the promoters and inhibitors of mitochondrial apoptosis is crucial, as demonstrated by the interplay among the Bcl-2 family members. In particular, B-cell lymphoma extra-large (Bcl-xL) is a target of interest due to the forefront role of its dysfunctions in cancer development. Bcl-xL prevents apoptosis by binding both the pro-apoptotic BH3-only proteins, like PUMA, and the noncanonical partners, such as p53, at different sites. An allosteric communication between the BH3-only protein binding pocket and the p53 binding site, mediating the release of p53 from Bcl-xL upon PUMA binding, has been postulated and supported by nuclear magnetic resonance and other biophysical data. The molecular details of this mechanism, especially at the residue level, remain unclear. In this work, we investigated the distal communication between these two sites in Bcl-xL in its free state and when bound to PUMA. We also evaluated how missense mutations of Bcl-xL found in cancer samples might impair this communication and therefore the allosteric mechanism. We employed all-atom explicit solvent microsecond molecular dynamics simulations, analyzed through a Protein Structure Network approach and integrated with calculations of changes in free energies upon cancer-related mutations identified by genomics studies. We found a subset of candidate residues responsible for both maintaining protein stability and for conveying structural information between the two binding sites and hypothesized possible communication routes between specific residues at both sites.
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Affiliation(s)
- Valentina Sora
- Computational Biology Laboratory, Danish Cancer Society Research Center, 2100 Copenhagen, Denmark.,Cancer Systems Biology, Section for Bioinformatics, Department of Health and Technology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Dionisio Sanchez
- Computational Biology Laboratory, Danish Cancer Society Research Center, 2100 Copenhagen, Denmark
| | - Elena Papaleo
- Computational Biology Laboratory, Danish Cancer Society Research Center, 2100 Copenhagen, Denmark.,Cancer Systems Biology, Section for Bioinformatics, Department of Health and Technology, Technical University of Denmark, 2800 Lyngby, Denmark
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12
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Jirasko V, Lends A, Lakomek N, Fogeron M, Weber ME, Malär AA, Penzel S, Bartenschlager R, Meier BH, Böckmann A. Dimer Organization of Membrane‐Associated NS5A of Hepatitis C Virus as Determined by Highly Sensitive
1
H‐Detected Solid‐State NMR. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013296] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Alons Lends
- Physical Chemistry ETH Zurich 8093 Zurich Switzerland
| | | | - Marie‐Laure Fogeron
- Molecular Microbiology and Structural Biochemistry Labex Ecofect UMR 5086 CNRS Université de Lyon 1 7 passage du Vercors 69367 Lyon France
| | | | | | | | - Ralf Bartenschlager
- Department of Infectious Diseases Molecular Virology Heidelberg University Im Neuenheimer Feld 345 69120 Heidelberg Germany
- German Centre for Infection Research (DZIF) Heidelberg partner site Heidelberg Germany
| | - Beat H. Meier
- Physical Chemistry ETH Zurich 8093 Zurich Switzerland
| | - Anja Böckmann
- Molecular Microbiology and Structural Biochemistry Labex Ecofect UMR 5086 CNRS Université de Lyon 1 7 passage du Vercors 69367 Lyon France
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13
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Jirasko V, Lends A, Lakomek N, Fogeron M, Weber ME, Malär AA, Penzel S, Bartenschlager R, Meier BH, Böckmann A. Dimer Organization of Membrane-Associated NS5A of Hepatitis C Virus as Determined by Highly Sensitive 1 H-Detected Solid-State NMR. Angew Chem Int Ed Engl 2021; 60:5339-5347. [PMID: 33205864 PMCID: PMC7986703 DOI: 10.1002/anie.202013296] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/17/2020] [Indexed: 12/17/2022]
Abstract
The Hepatitis C virus nonstructural protein 5A (NS5A) is a membrane-associated protein involved in multiple steps of the viral life cycle. Direct-acting antivirals (DAAs) targeting NS5A are a cornerstone of antiviral therapy, but the mode-of-action of these drugs is poorly understood. This is due to the lack of information on the membrane-bound NS5A structure. Herein, we present the structural model of an NS5A AH-linker-D1 protein reconstituted as proteoliposomes. We use highly sensitive proton-detected solid-state NMR methods suitable to study samples generated through synthetic biology approaches. Spectra analyses disclose that both the AH membrane anchor and the linker are highly flexible. Paramagnetic relaxation enhancements (PRE) reveal that the dimer organization in lipids requires a new type of NS5A self-interaction not reflected in previous crystal structures. In conclusion, we provide the first characterization of NS5A AH-linker-D1 in a lipidic environment shedding light onto the mode-of-action of clinically used NS5A inhibitors.
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Affiliation(s)
| | - Alons Lends
- Physical ChemistryETH Zurich8093ZurichSwitzerland
| | | | - Marie‐Laure Fogeron
- Molecular Microbiology and Structural BiochemistryLabex EcofectUMR 5086 CNRSUniversité de Lyon 17 passage du Vercors69367LyonFrance
| | | | | | | | - Ralf Bartenschlager
- Department of Infectious DiseasesMolecular VirologyHeidelberg UniversityIm Neuenheimer Feld 34569120HeidelbergGermany
- German Centre for Infection Research (DZIF)Heidelberg partner siteHeidelbergGermany
| | | | - Anja Böckmann
- Molecular Microbiology and Structural BiochemistryLabex EcofectUMR 5086 CNRSUniversité de Lyon 17 passage du Vercors69367LyonFrance
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14
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Sinha S, Ghosh Dastidar S. Shifting Polar Residues Across Primary Sequence Frames of Transmembrane Domains Calibrates Membrane Permeation Thermodynamics. Biochemistry 2020; 59:4353-4366. [PMID: 33136366 DOI: 10.1021/acs.biochem.0c00536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Permeation of the mitochondrial outer membrane (MOM) using the transmembrane domains (TMDs) is the key step of the Bcl-2 family of proteins to control apoptosis. The primary sequences of the TMDs of the family members like Bcl-xL, Bcl-2, Bak, etc. indicate the presence of charged residues at the C-terminal tip to be essential for drilling the membrane. However, Bax, a variant of the same family, is an exception, as the charged residues are shifted away from the tip by two positional frames in the primary sequence, but does it matter really? The free energy landscapes of membrane permeation, computed from a total of ∼13.3 μs of conformational sampling, show how such shifting of the amino acid frames in the primary sequence is correlated with the energy landscape that ensures the balance between membrane permeation and cytosolic population. Shifting the charged residues back to the terminal, in suitable mutants of Bax, proves the necessity of terminal charged residues by improving the insertion free energy but adds a high energy barrier unless some other polar residues are adjusted further. The difference in the TMDs of Bcl-xL and Bax is also reflected in their mechanism to drill the MOM-like anionic membrane; only Bax-TMD requires surface crowding to favorably shape the permeation landscape by weakening the bilayer integrity. So, this investigation suggests that such proteins can calibrate the free energy landscape of membrane permeation by adjusting the positions of the charged or polar residues in the primary sequence frames, a strategy analogous to the game of the "sliding tile puzzle" but played with primary sequence frames.
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Affiliation(s)
- Souvik Sinha
- Division of Bioinformatics, Bose Institute, P-1/12 CIT Scheme VII M, Kolkata 700054, India
| | - Shubhra Ghosh Dastidar
- Division of Bioinformatics, Bose Institute, P-1/12 CIT Scheme VII M, Kolkata 700054, India
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15
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Ryzhov P, Tian Y, Yao Y, Bobkov AA, Im W, Marassi FM. Conformational States of the Cytoprotective Protein Bcl-xL. Biophys J 2020; 119:1324-1334. [PMID: 32888404 PMCID: PMC7567986 DOI: 10.1016/j.bpj.2020.08.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 07/01/2020] [Accepted: 08/17/2020] [Indexed: 12/20/2022] Open
Abstract
Bcl-xL is a major inhibitor of apoptosis, a fundamental homeostatic process of programmed cell death that is highly conserved across evolution. Because it plays prominent roles in cancer, Bcl-xL is a major target for anticancer therapy and for studies aimed at understanding its structure and activity. Although Bcl-xL is active primarily at intracellular membranes, most studies have focused on soluble forms of the protein lacking both the membrane-anchoring C-terminal tail and the intrinsically disordered loop, and this has resulted in a fragmented view of the protein's biological activity. Here, we describe the conformation of full-length Bcl-xL. Using NMR spectroscopy, molecular dynamics simulations, and isothermal titration calorimetry, we show how the three structural elements affect the protein's structure, dynamics, and ligand-binding activity in both its soluble and membrane-anchored states. The combined data provide information about the molecular basis for the protein's functionality and a view of its complex molecular mechanisms.
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Affiliation(s)
- Pavel Ryzhov
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Ye Tian
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Yong Yao
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Andrey A Bobkov
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Wonpil Im
- Departments of Biological Sciences, Chemistry, and Bioengineering, Lehigh University, Bethlehem, Pennsylvania
| | - Francesca M Marassi
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California.
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16
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Häusler E, Fredriksson K, Goba I, Peters C, Raltchev K, Sperl L, Steiner A, Weinkauf S, Hagn F. Quantifying the insertion of membrane proteins into lipid bilayer nanodiscs using a fusion protein strategy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183190. [DOI: 10.1016/j.bbamem.2020.183190] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 12/13/2022]
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17
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Li J, Zhang Y, Soubias O, Khago D, Chao FA, Li Y, Shaw K, Byrd RA. Optimization of sortase A ligation for flexible engineering of complex protein systems. J Biol Chem 2020; 295:2664-2675. [PMID: 31974162 DOI: 10.1074/jbc.ra119.012039] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/22/2020] [Indexed: 01/06/2023] Open
Abstract
Engineering and bioconjugation of proteins is a critically valuable tool that can facilitate a wide range of biophysical and structural studies. The ability to orthogonally tag or label a domain within a multidomain protein may be complicated by undesirable side reactions to noninvolved domains. Furthermore, the advantages of segmental (or domain-specific) isotopic labeling for NMR, or deuteration for neutron scattering or diffraction, can be realized by an efficient ligation procedure. Common methods-expressed protein ligation, protein trans-splicing, and native chemical ligation-each have specific limitations. Here, we evaluated the use of different variants of Staphylococcus aureus sortase A for a range of ligation reactions and demonstrate that conditions can readily be optimized to yield high efficiency (i.e. completeness of ligation), ease of purification, and functionality in detergents. These properties may enable joining of single domains into multidomain proteins, lipidation to mimic posttranslational modifications, and formation of cyclic proteins to aid in the development of nanodisc membrane mimetics. We anticipate that the method for ligating separate domains into a single functional multidomain protein reported here may enable many applications in structural biology.
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Affiliation(s)
- Jess Li
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Yue Zhang
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Olivier Soubias
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Domarin Khago
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Fa-An Chao
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Yifei Li
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - Katherine Shaw
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201
| | - R Andrew Byrd
- Structural Biophysics Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Frederick, Maryland 21702-1201.
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18
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Nuijens T, Toplak A, Schmidt M, Ricci A, Cabri W. Natural Occurring and Engineered Enzymes for Peptide Ligation and Cyclization. Front Chem 2019; 7:829. [PMID: 31850317 PMCID: PMC6895249 DOI: 10.3389/fchem.2019.00829] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/14/2019] [Indexed: 12/16/2022] Open
Abstract
The renaissance of peptides as prospective therapeutics has fostered the development of novel strategies for their synthesis and modification. In this context, besides the development of new chemical peptide ligation approaches, especially the use of enzymes as a versatile tool has gained increased attention. Nowadays, due to their inherent properties such as excellent regio- and chemoselectivity, enzymes represent invaluable instruments in both academic and industrial laboratories. This mini-review focuses on natural- and engineered peptide ligases that can form a new peptide (amide) bond between the C-terminal carboxy and N-terminal amino group of a peptide and/or protein. The pro's and cons of several enzyme classes such as Sortases, Asparaginyl Endoproteases, Trypsin related enzymes and as a central focus subtilisin-derived variants are summarized. Most recent developments with regards to ligation and cyclization are highlighted.
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Affiliation(s)
- Timo Nuijens
- Fresenius Kabi iPSUM, I&D Center EnzyPep B.V., Geleen, Netherlands
| | - Ana Toplak
- Fresenius Kabi iPSUM, I&D Center EnzyPep B.V., Geleen, Netherlands
| | - Marcel Schmidt
- Fresenius Kabi iPSUM, I&D Center EnzyPep B.V., Geleen, Netherlands
| | | | - Walter Cabri
- Fresenius Kabi iPSUM, I&D Center EnzyPep B.V., Geleen, Netherlands
- Fresenius Kabi iPSUM Srl, Villadose, Italy
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19
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Klöpfer K, Hagn F. Beyond detergent micelles: The advantages and applications of non-micellar and lipid-based membrane mimetics for solution-state NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:271-283. [PMID: 31779883 DOI: 10.1016/j.pnmrs.2019.08.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/20/2019] [Accepted: 08/22/2019] [Indexed: 06/10/2023]
Abstract
Membrane proteins are important players in signal transduction and the exchange of metabolites within or between cells. Thus, this protein class is the target of around 60 % of currently marketed drugs, emphasizing their essential biological role. Besides functional assays, structural and dynamical investigations on this protein class are crucial to fully understanding their functionality. Even though X-ray crystallography and electron microscopy are the main methods to determine structures of membrane proteins and their complexes, NMR spectroscopy can contribute essential information on systems that (a) do not crystallize and (b) are too small for EM. Furthermore, NMR is a versatile tool for monitoring functional dynamics of biomolecules at various time scales. A crucial aspect of such studies is the use of a membrane mimetic that resembles a native environment and thus enables the extraction of functional insights. In recent decades, the membrane protein NMR community has moved from rather harsh detergents to membrane systems having more native-like properties. In particular, most recently phospholipid nanodiscs have been developed and optimized mainly for solution-state NMR but are now also being used for solid-state NMR spectroscopy. Nanodiscs consist of a patch of a planar lipid bilayer that is encircled by different (bio-)polymers to form particles of defined and tunable size. In this review, we provide an overview of available membrane mimetics, including nanodiscs, amphipols and bicelles, that are suitable for high-resolution NMR spectroscopy and describe how these advanced membrane mimetics can facilitate NMR studies on the structure and dynamics of membrane proteins. Since the stability of membrane proteins depends critically on the chosen membrane mimetic, we emphasize the importance of a suitable system that is not necessarily developed for solution-state NMR applications and hence requires optimization for each membrane protein. However, lipid-based membrane mimetics offer the possibility of performing NMR experiments at elevated temperatures and studying ligand and partner protein complexes as well as their functional dynamics in a realistic membrane environment. In order to be able to make an informed decision during the selection of a suitable membrane system, we provide a detailed overview of the available options for various membrane protein classes and thereby facilitate this often-difficult selection process for a broad range of desired NMR applications.
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Affiliation(s)
- Kai Klöpfer
- Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85747 Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Franz Hagn
- Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Str. 2, 85747 Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
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20
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The Structural Biology of Bcl-x L. Int J Mol Sci 2019; 20:ijms20092234. [PMID: 31067648 PMCID: PMC6540150 DOI: 10.3390/ijms20092234] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 01/12/2023] Open
Abstract
Interactions between the pro-survival and pro-apoptotic members of the Bcl-2 family of proteins dictate whether a cell lives or dies. Much of our knowledge of the molecular details of these interactions has come from biochemical and structural studies on the pro-survival protein Bcl-xL. The first high-resolution structure of any Bcl-2 family member was of Bcl-xL, which revealed the conserved topology amongst all family members. Subsequent structures of Bcl-xL complexes with pro-apoptotic ligands demonstrated the general features of all pro-survival:pro-apoptotic complexes. Structural studies involving Bcl-xL were also the basis for the discovery of the first small-molecule pro-survival protein inhibitors, leading ultimately to the development of a new class of drugs now successfully used for cancer treatment in the clinic. This article will review our current knowledge of the structural biology of Bcl-xL and how this has impacted our understanding of the molecular details of the intrinsic apoptotic pathway.
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21
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Dai X, Böker A, Glebe U. Broadening the scope of sortagging. RSC Adv 2019; 9:4700-4721. [PMID: 35514663 PMCID: PMC9060782 DOI: 10.1039/c8ra06705h] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 01/31/2019] [Indexed: 01/20/2023] Open
Abstract
Sortases are enzymes occurring in the cell wall of Gram-positive bacteria. Sortase A (SrtA), the best studied sortase class, plays a key role in anchoring surface proteins with the recognition sequence LPXTG covalently to oligoglycine units of the bacterial cell wall. This unique transpeptidase activity renders SrtA attractive for various purposes and motivated researchers to study multiple in vivo and in vitro ligations in the last decades. This ligation technique is known as sortase-mediated ligation (SML) or sortagging and developed to a frequently used method in basic research. The advantages are manifold: extremely high substrate specificity, simple access to substrates and enzyme, robust nature and easy handling of sortase A. In addition to the ligation of two proteins or peptides, early studies already included at least one artificial (peptide equipped) substrate into sortagging reactions - which demonstrates the versatility and broad applicability of SML. Thus, SML is not only a biology-related technique, but has found prominence as a major interdisciplinary research tool. In this review, we provide an overview about the use of sortase A in interdisciplinary research, mainly for protein modification, synthesis of protein-polymer conjugates and immobilization of proteins on surfaces.
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Affiliation(s)
- Xiaolin Dai
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam 14476 Potsdam-Golm Germany
| | - Alexander Böker
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam 14476 Potsdam-Golm Germany
| | - Ulrich Glebe
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
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22
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Maity A, Sinha S, Ghosh Dastidar S. Dissecting the thermodynamic contributions of the charged residues in the membrane anchoring of Bcl-xl C-terminal domain. Chem Phys Lipids 2018; 218:112-124. [PMID: 30550879 DOI: 10.1016/j.chemphyslip.2018.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 11/20/2018] [Accepted: 12/09/2018] [Indexed: 11/28/2022]
Abstract
The C-terminal helix of the Bcl-xl is known to initiate the membrane insertion of the protein by anchoring into the mitochondrial outer membrane. The C-terminal charged residues of that helix, R232 and K233, are reported to have an important structural role in the process of that insertion. The present work provides a quantitative understanding of the thermodynamic contribution of these residues on the membrane insertion energy-profile, calculated from the Adaptive Biasing Force based MD simulations of 2.67 μs altogether. Interestingly, the effect of the single neutralizing mutations at the C-terminus, i.e. K233A or R232A, is easily tolerated by the peptide without impacting the nature of insertion energy-profile, indicating the efficiency of one positively charged residue to drive the insertion. Whereas a double mutant, i.e. R232A and K233A, makes a significant impact on the energy-profile by destabilizing the membrane-associated states, as well as the membrane-embedded states. The finding provides molecular-level mechanistic insight. The water-mediated interaction formed by the peptide polar side chains within the bilayer core is found to modulate the membrane response during peptide insertion and that subsequently regulates the insertion mechanism. Mutation of the C-terminal residues eventually alters such a cascade of interactions that results in an insertion through energetically more expensive pathway. Since any one of the positively charged residues at the terminal is critical to ensure the membrane insertion, it appears that the natural selection of 'two' instead of 'one' charged residue is redundant in the context of membrane anchoring but may be important for other biochemical events.
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Affiliation(s)
- Atanu Maity
- Division of Bioinformatics, Bose Institute, P-1/12 C.I.T. Scheme VII M, Kolkata, 700054, India
| | - Souvik Sinha
- Division of Bioinformatics, Bose Institute, P-1/12 C.I.T. Scheme VII M, Kolkata, 700054, India
| | - Shubhra Ghosh Dastidar
- Division of Bioinformatics, Bose Institute, P-1/12 C.I.T. Scheme VII M, Kolkata, 700054, India.
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23
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Miehling J, Goricanec D, Hagn F. A Split-Intein-Based Method for the Efficient Production of Circularized Nanodiscs for Structural Studies of Membrane Proteins. Chembiochem 2018; 19:1927-1933. [DOI: 10.1002/cbic.201800345] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Jonas Miehling
- Bavarian NMR Center at the Department of Chemistry, and Institute for Advanced Study; Technical University of Munich; Lichtenbergstrasse 4 85747 Garching Germany
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstrasse 1 85764 Neuherberg Germany
| | - David Goricanec
- Bavarian NMR Center at the Department of Chemistry, and Institute for Advanced Study; Technical University of Munich; Lichtenbergstrasse 4 85747 Garching Germany
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstrasse 1 85764 Neuherberg Germany
| | - Franz Hagn
- Bavarian NMR Center at the Department of Chemistry, and Institute for Advanced Study; Technical University of Munich; Lichtenbergstrasse 4 85747 Garching Germany
- Institute of Structural Biology; Helmholtz Zentrum München; Ingolstädter Landstrasse 1 85764 Neuherberg Germany
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