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Solov'eva TF, Bakholdina SI, Khomenko VA, Sidorin EV, Kim NY, Novikova OD, Shnyrov VL, Stenkova AM, Eremeev VI, Bystritskaya EP, Isaeva MP. Expression of membrane beta-barrel protein in E. coli at low temperatures: Structure of Yersinia pseudotuberculosis OmpF porin inclusion bodies. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183971. [PMID: 35643329 DOI: 10.1016/j.bbamem.2022.183971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 04/14/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
The recombinant OmpF porin of Yersinia pseudotuberculosis as a model of transmembrane protein of the β-barrel structural family was used to study low growth temperature effect on the structure of the produced inclusion bodies (IBs). This porin showed a very low expression level in E. coli at a growth temperature below optimal 37 °C. The introduction of a N-terminal hexahistidine tag into the mature porin molecule significantly increased the biosynthesis of the protein at low cultivation temperatures. The recombinant His-tagged porin (rOmpF-His) was expressed in E. coli at 30 and 18 °C as inclusion bodies (IB-30 and IB-18). The properties and structural organization of IBs, as well as the structure of rOmpF-His solubilized from the IBs with urea and SDS, were studied using turbidimetry, electron microscopy, dynamic light scattering, optical spectroscopy, and amyloid-specific dyes. IB-18, in comparison with IB-30, has a higher solubility in denaturants, suggesting a difference between IBs in the conformation of the associated polypeptide chains. The spectroscopic analysis revealed that rOmpF-His IBs have a high content of secondary structure with a tertiary-structure elements, including a native-like conformation, the proportion of which in IB-18 is higher than in IB-30. Solubilization of the porin from IBs is accompanied by a modification of its secondary structure. The studied IBs also contain amyloid-like structures. The results obtained in this study expand our knowledge of the structural organization of IBs formed by proteins of different structural classes and also have a contribution into the new approaches development of producing functionally active recombinant membrane proteins.
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Affiliation(s)
- Tamara F Solov'eva
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Svetlana I Bakholdina
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia.
| | - Valentina A Khomenko
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Evgeniy V Sidorin
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Natalya Yu Kim
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Olga D Novikova
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Valery L Shnyrov
- Departamento de Bioquimica y Biologia Molecular, Universidad de Salamanca, Plaza Doctores de la Reina s/n, 37007 Salamanca, Spain
| | - Anna M Stenkova
- Far Eastern Federal University School of Biomedicine, Russky Island Ajax Bay 10, 690922 Vladivostok, Russia
| | - Vyacheslav I Eremeev
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Evgenia P Bystritskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
| | - Marina P Isaeva
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia
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Gong J, Zhu M, Zhan M, Xi C, Xu Z, Shui Y, Shen H. PcVDAC promotes WSSV infection by regulating the apoptotic activity of haemocytes in Procambarus clarkii. Comp Biochem Physiol B Biochem Mol Biol 2021; 259:110697. [PMID: 34798242 DOI: 10.1016/j.cbpb.2021.110697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/07/2021] [Accepted: 11/12/2021] [Indexed: 11/15/2022]
Abstract
Apoptosis is programmed cell death that is strictly regulated by a series of related genes and is of great importance in resisting pathogen invasion and maintaining cell environment homeostasis. Among apoptotic proteins, the voltage-dependent anion channel protein (VDAC) plays a key role in the mitochondrial apoptosis pathway because of its close connection with changes in mitochondrial membrane potential. However, the role of VDAC in apoptosis and immune regulation in Procambarus clarkii is poorly understood. In this study, the VDAC gene in P. clarkii (PcVDAC) was cloned by rapid amplification of cDNA ends (RACE) technology. The gene was found to have a total length of 2277 bp, including a 194-bp 5'-UTR, 1234-bp 3'-UTR and 849-bp open reading frame (ORF), and to encode 282 amino acids. PcVDAC was expressed in all tissues tested, and its expression was upregulated after white spot syndrome virus (WSSV) infection (P < 0.05). The RNA interference (RNAi) method was used to explore the role of PcVDAC in WSSV infection. The results showed that the number of WSSV copies in haemocytes was significantly reduced after RNAi (P < 0.05), and the survival rate was significantly increased. In addition, after RNAi, the apoptosis rate was significantly increased (P < 0.05), the mitochondrial membrane potential was reduced (P < 0.01), and the expression of caspase-3 and other genes was upregulated (P < 0.05). These results indicate that PcVDAC promotes the replication of WSSV in P. clarkii by inhibiting haemocytes apoptosis. Therefore, the results presented in this paper provide new insights into the immune response of P. clarkii infected with WSSV.
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Affiliation(s)
- Jie Gong
- Wuxi Fisheries College, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Mengru Zhu
- Wuxi Fisheries College, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Ming Zhan
- Wuxi Fisheries College, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Changjun Xi
- Wuxi Fisheries College, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Zenghong Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
| | - Yan Shui
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
| | - Huaishun Shen
- Wuxi Fisheries College, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
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Benz R. Historical Perspective of Pore-Forming Activity Studies of Voltage-Dependent Anion Channel (Eukaryotic or Mitochondrial Porin) Since Its Discovery in the 70th of the Last Century. Front Physiol 2021; 12:734226. [PMID: 35547863 PMCID: PMC9083909 DOI: 10.3389/fphys.2021.734226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/24/2021] [Indexed: 01/07/2023] Open
Abstract
Eukaryotic porin, also known as Voltage-Dependent Anion Channel (VDAC), is the most frequent protein in the outer membrane of mitochondria that are responsible for cellular respiration. Mitochondria are most likely descendants of strictly aerobic Gram-negative bacteria from the α-proteobacterial lineage. In accordance with the presumed ancestor, mitochondria are surrounded by two membranes. The mitochondrial outer membrane contains besides the eukaryotic porins responsible for its major permeability properties a variety of other not fully identified channels. It encloses also the TOM apparatus together with the sorting mechanism SAM, responsible for the uptake and assembly of many mitochondrial proteins that are encoded in the nucleus and synthesized in the cytoplasm at free ribosomes. The recognition and the study of electrophysiological properties of eukaryotic porin or VDAC started in the late seventies of the last century by a study of Schein et al., who reconstituted the pore from crude extracts of Paramecium mitochondria into planar lipid bilayer membranes. Whereas the literature about structure and function of eukaryotic porins was comparatively rare during the first 10years after the first study, the number of publications started to explode with the first sequencing of human Porin 31HL and the recognition of the important function of eukaryotic porins in mitochondrial metabolism. Many genomes contain more than one gene coding for homologs of eukaryotic porins. More than 100 sequences of eukaryotic porins are known to date. Although the sequence identity between them is relatively low, the polypeptide length and in particular, the electrophysiological characteristics are highly preserved. This means that all eukaryotic porins studied to date are anion selective in the open state. They are voltage-dependent and switch into cation-selective substates at voltages in the physiological relevant range. A major breakthrough was also the elucidation of the 3D structure of the eukaryotic pore, which is formed by 19 β-strands similar to those of bacterial porin channels. The function of the presumed gate an α-helical stretch of 20 amino acids allowed further studies with respect to voltage dependence and function, but its exact role in channel gating is still not fully understood.
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Affiliation(s)
- Roland Benz
- Department of Life Sciences and Chemistry, Jacobs University Bremen, Bremen, Germany
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The N-terminus of VDAC: Structure, mutational analysis, and a potential role in regulating barrel shape. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1350-61. [PMID: 26997586 DOI: 10.1016/j.bbamem.2016.03.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/12/2016] [Accepted: 03/17/2016] [Indexed: 01/24/2023]
Abstract
A novel feature of the voltage-dependent anion channel (VDAC, mitochondrial porin), is the barrel, comprising an odd number of β-strands and closed by parallel strands. Recent research has focused on the N-terminal segment, which in the available structures, resides in the lumen and is not part of the barrel. In this review, the structural data obtained from vertebrate VDAC are integrated with those from VDAC in artificial bilayers, emphasizing the array of native and tagged versions of VDAC used. The data are discussed with respect to a recent gating model (Zachariae et al. (2012) Structure 20:1-10), in which the N-terminus acts not as a gate on a stable barrel, but rather stabilizes the barrel, preventing its shift into a partially collapsed, low-conductance, closed state. Additionally, the role of the N-terminus in VDAC oligomerization, apoptosis through interactions with hexokinase and its interaction with ATP are discussed briefly.
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Villinger S, Giller K, Bayrhuber M, Lange A, Griesinger C, Becker S, Zweckstetter M. Nucleotide interactions of the human voltage-dependent anion channel. J Biol Chem 2014; 289:13397-406. [PMID: 24668813 DOI: 10.1074/jbc.m113.524173] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The voltage-dependent anion channel (VDAC) mediates and gates the flux of metabolites and ions across the outer mitochondrial membrane and is a key player in cellular metabolism and apoptosis. Here we characterized the binding of nucleotides to human VDAC1 (hVDAC1) on a single-residue level using NMR spectroscopy and site-directed mutagenesis. We find that hVDAC1 possesses one major binding region for ATP, UTP, and GTP that partially overlaps with a previously determined NADH binding site. This nucleotide binding region is formed by the N-terminal α-helix, the linker connecting the helix to the first β-strand and adjacent barrel residues. hVDAC1 preferentially binds the charged forms of ATP, providing support for a mechanism of metabolite transport in which direct binding to the charged form exerts selectivity while at the same time permeation of the Mg(2+)-complexed ATP form is possible.
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Affiliation(s)
- Saskia Villinger
- From the Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
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Homblé F, Krammer EM, Prévost M. Plant VDAC: facts and speculations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:1486-501. [PMID: 22155681 DOI: 10.1016/j.bbamem.2011.11.028] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 11/12/2011] [Accepted: 11/22/2011] [Indexed: 01/01/2023]
Abstract
The voltage-dependent anion-selective channel (VDAC) is the most abundant protein in the mitochondrial outer membrane and the major transport pathway for a large variety of compounds ranging from ions to large polymeric molecules such as DNA and tRNA. Plant VDACs feature a secondary structure content and electrophysiological properties akin to those of VDACs from other organisms. They however undergo a specific regulation. The general importance of VDAC in plant physiology has only recently emerged. Besides their role in metabolite transport, plant VDACs are also involved in the programmed cell death triggered in response to biotic and abiotic stresses. Moreover, their colocalization in non-mitochondrial membranes suggests a diversity of function. This review summarizes our current understanding of the structure and function of plant VDACs. This article is part of a Special Issue entitled: VDAC structure, function, and regulation of mitochondrial metabolism.
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Affiliation(s)
- Fabrice Homblé
- Structure et Fontion des Membranes Biologiques, Centre de Biologie Structurale et de Bioinformatique, Université Libre de Bruxelles, Boulevard du Triomphe CP, Brussels, Belgium.
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Wang KCHC, Kondo H, Hirono I, Aoki T. The Marsupenaeus japonicus voltage-dependent anion channel (MjVDAC) protein is involved in white spot syndrome virus (WSSV) pathogenesis. FISH & SHELLFISH IMMUNOLOGY 2010; 29:94-103. [PMID: 20202479 DOI: 10.1016/j.fsi.2010.02.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 02/19/2010] [Accepted: 02/22/2010] [Indexed: 05/28/2023]
Abstract
Voltage-dependent anion channel (VDAC) proteins abound in the outer membrane of mitochondria. They play an important role in mitochondrial membrane permeabilization (MMP), which can lead to stress-induced cellular apoptosis and necrosis. Several pathogens regulate this MMP in their host cells to benefit their replication cycle, while in other cases, the host can use the same mechanism to combat pathogenesis. In this study, the first shrimp VDAC gene was identified and characterized from Marsupenaeus japonicus (MjVDAC). Its open reading frame (ORF) contained 849 bp encoding 282 amino acids. The deduced MjVDAC protein includes the 4-element eukaryotic porin signature motif, the conserved ATP binding motif (the GLK motif) and a VKAKV-like sequence known in other organisms to be involved in the protein's incorporation in the mitochondrial outer membrane. Tissue tropism analysis indicated that MjVDAC is abundant in the heart, muscle, stomach and pleopod. MjVDAC proteins colocalized with mitochondria in transiently transfected Sf9 cells and in shrimp hemocytes. dsRNA silencing of shrimp VDAC delayed white spot syndrome virus (WSSV) infection by 1 day in different shrimp organs. Taken together, these findings suggest that MjVDAC is likely to be involved in WSSV pathogenesis.
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Affiliation(s)
- K C Han-Ching Wang
- Laboratory of Genome Science, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
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8
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Abstract
Precise information regarding the transmembrane topology of mitochondrial porin is essential for understanding the mechanisms by which this protein functions. Porin acts as a channel in the outer membrane and interacts with small solutes and proteins to regulate mitochondrial function. The acquisition of high-resolution structural data requires a method of maintaining high concentrations of unaggregated, properly folded porin. In the current studies, several mixed detergent systems were analyzed for their ability to fold Neurospora mitochondrial porin expressed in and isolated from Escherichia coli. A mixture of sodium dodecyl sulfate and dodecyl-beta-D-maltopyranoside in a 1:6 molar ratio supports a beta-strand-rich conformation. In this state, the two tryptophan residues in the protein reside in hydrophobic environments, and about half of the nine tyrosines are solvent exposed. Most importantly, heat-labile tertiary contacts, as detected by near-UV circular dichroism spectropolarimetry, in the sodium dodecyl sulfate/dodecyl-beta-D-maltopyranoside-solubilized porin are very similar to those of the protein following functional reconstitution into liposomes. Similarly, both forms are protease resistant. Thus, a method has been identified with the potential to solubilize high concentrations of mitochondrial porin in a state virtually indistinguishable from the membrane-embedded form.
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Affiliation(s)
- Denice C Bay
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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Abstract
BACKGROUND Mitochondrial porins, or voltage-dependent anion-selective channels (VDAC) allow the passage of small molecules across the mitochondrial outer membrane, and are involved in complex interactions regulating organellar and cellular metabolism. Numerous organisms possess multiple porin isoforms, and initial studies indicated an intriguing evolutionary history for these proteins and the genes that encode them. RESULTS In this work, the wealth of recent sequence information was used to perform a comprehensive analysis of the evolutionary history of mitochondrial porins. Fungal porin sequences were well represented, and newly-released sequences from stramenopiles, alveolates, and seed and flowering plants were analyzed. A combination of Neighbour-Joining and Bayesian methods was used to determine phylogenetic relationships among the proteins. The aligned sequences were also used to reassess the validity of previously described eukaryotic porin motifs and to search for signature sequences characteristic of VDACs from plants, animals and fungi. Secondary structure predictions were performed on the aligned VDAC primary sequences and were used to evaluate the sites of intron insertion in a representative set of the corresponding VDAC genes. CONCLUSION Our phylogenetic analysis clearly shows that paralogs have appeared several times during the evolution of VDACs from the plants, metazoans, and even the fungi, suggesting that there are no "ancient" paralogs within the gene family. Sequence motifs characteristic of the members of the crown groups of organisms were identified. Secondary structure predictions suggest a common 16 beta-strand framework for the transmembrane arrangement of all porin isoforms. The GLK (and homologous or analogous motifs) and the eukaryotic porin motifs in the four representative Chordates tend to be in exons that appear to have changed little during the evolution of these metazoans. In fact there is phase correlation among the introns in these genes. Finally, our preliminary data support the notion that introns usually do not interrupt structural protein motifs, namely the predicted beta-strands. These observations concur with the concept of exon shuffling, wherein exons encode structural modules of proteins and the loss and gain of introns and the shuffling of exons via recombination events contribute to the complexity of modern day proteomes.
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Runke G, Maier E, Summers WAT, Bay DC, Benz R, Court DA. Deletion variants of Neurospora mitochondrial porin: electrophysiological and spectroscopic analysis. Biophys J 2006; 90:3155-64. [PMID: 16500966 PMCID: PMC1432131 DOI: 10.1529/biophysj.105.072520] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial porins are predicted to traverse the outer membrane as a series of beta-strands, but the precise structure of the resulting beta-barrel has remained elusive. Toward determining the positions of the membrane-spanning segments, a series of small deletions was introduced into several of the predicted beta-strands of the Neurospora crassa porin. Overall, three classes of porin variants were identified: i), those producing large, stable pores, indicating deletions likely outside of beta-strands; ii), those with minimal pore-forming ability, indicating disruptions in key beta-strands or beta-turns; and iii), those that formed small unstable pores with a variety of gating and ion-selectivity properties. The latter class presumably results from a subset of proteins that adopt an alternative barrel structure upon the loss of stabilizing residues. Some variants were not sufficiently stable in detergent for structural analysis; circular dichroism spectropolarimetry of those that were did not reveal significant differences in the overall structural composition among the detergent-solubilized porin variants and the wild-type protein. Several of the variants displayed altered tryptophan fluorescence profiles, indicative of differing microenvironments surrounding these residues. Based on these results, modifications to the existing models for porin structure are proposed.
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Affiliation(s)
- Greg Runke
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 Canada
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Bay DC, Court DA. Origami in the outer membrane: the transmembrane arrangement of mitochondrial porins. Biochem Cell Biol 2003; 80:551-62. [PMID: 12440696 DOI: 10.1139/o02-149] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Voltage-dependent anion-selective channels (VDAC), also known as mitochondrial porins, are key regulators of metabolite flow across the mitochondrial outer membrane. Porins from a wide variety of organisms share remarkably similar electrophysiological properties, in spite of considerable sequence dissimilarity, indicating that they share a common structure. Based on primary sequence considerations, analogy with bacterial porins, and circular dichroism analysis, it is agreed that VDAC spans the outer membrane as a beta-barrel. However, the residues that form the antiparallel beta-strands comprising this barrel remain unknown. Various predictive methods, largely based on the known structures of bacterial beta-barrels, have been applied to the primary sequences of VDAC. Refinement and confirmation of these predictions have developed through numerous investigations of wild-type and variant porins, both in mitochondria and in artificial membranes. These experiments have involved VDAC from several sources, precluding the generation of a unified model. Herein, using the Neurospora VDAC sequence as a template, the published structural information and predictions have been reassessed to delineate a model that satisfies most of the available data.
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Affiliation(s)
- Denice C Bay
- Department of Microbiology, University of Manitoba, Winnipeg, Canada
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