1
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Top J, Zhang X, Hendrickx APA, Boeren S, van Schaik W, Huebner J, Willems RJL, Leavis HL, Paganelli FL. YajC, a predicted membrane protein, promotes Enterococcus faecium biofilm formation in vitro and in a rat endocarditis model. FEMS MICROBES 2024; 5:xtae017. [PMID: 38860142 PMCID: PMC11163983 DOI: 10.1093/femsmc/xtae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/25/2024] [Accepted: 05/17/2024] [Indexed: 06/12/2024] Open
Abstract
Biofilm formation is a critical step in the pathogenesis of difficult-to-treat Gram-positive bacterial infections. We identified that YajC, a conserved membrane protein in bacteria, plays a role in biofilm formation of the clinically relevant Enterococcus faecium strain E1162. Deletion of yajC conferred significantly impaired biofilm formation in vitro and was attenuated in a rat endocarditis model. Mass spectrometry analysis of supernatants of washed ΔyajC cells revealed increased amounts in cytoplasmic and cell-surface-located proteins, including biofilm-associated proteins, suggesting that proteins on the surface of the yajC mutant are only loosely attached. In Streptococcus mutans YajC has been identified in complex with proteins of two cotranslational membrane protein-insertion pathways; the signal recognition particle (SRP)-SecYEG-YajC-YidC1 and the SRP-YajC-YidC2 pathway, but its function is unknown. In S. mutans mutation of yidC1 and yidC2 resulted in impaired protein insertion in the cell membrane and secretion in the supernatant. The E. faecium genome contains all homologous genes encoding for the cotranslational membrane protein-insertion pathways. By combining the studies in S. mutans and E. faecium, we propose that YajC is involved in the stabilization of the SRP-SecYEG-YajC-YidC1 and SRP-YajC-Yid2 pathway or plays a role in retaining proteins for proper docking to the YidC insertases for translocation in and over the membrane.
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Affiliation(s)
- Janetta Top
- Department of Medical Microbiology, University Medical Center Utrecht, PO box 85500, 3584 CX Utrecht, the Netherlands
| | - Xinglin Zhang
- College of Agriculture and Forestry, Linyi University, Building 60, Yujingwan, Linyi City, Shandong Province, 276000, China
| | - Antoni P A Hendrickx
- Centre for Infectious Disease Control (Clb), National Institute for Public Health and the Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, the Netherlands
| | - Sjef Boeren
- Laboratory of Biochemistry, Wageningen University, PO box 8128, 6700 ET Wageningen, the Netherlands
| | - Willem van Schaik
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Johannes Huebner
- Division of Pediatric Infectious Diseases, Hauner Children's Hospital, Ludwig-Maximilian Universität München, Lindwurmstr. 4, 80337 Munich, Germany
| | - Rob J L Willems
- Department of Medical Microbiology, University Medical Center Utrecht, PO box 85500, 3584 CX Utrecht, the Netherlands
| | - Helen L Leavis
- Department of Medical Microbiology, University Medical Center Utrecht, PO box 85500, 3584 CX Utrecht, the Netherlands
| | - Fernanda L Paganelli
- Department of Medical Microbiology, University Medical Center Utrecht, PO box 85500, 3584 CX Utrecht, the Netherlands
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2
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Knyazev DG, Winter L, Vogt A, Posch S, Öztürk Y, Siligan C, Goessweiner-Mohr N, Hagleitner-Ertugrul N, Koch HG, Pohl P. YidC from Escherichia coli Forms an Ion-Conducting Pore upon Activation by Ribosomes. Biomolecules 2023; 13:1774. [PMID: 38136645 PMCID: PMC10741985 DOI: 10.3390/biom13121774] [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: 11/05/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
The universally conserved protein YidC aids in the insertion and folding of transmembrane polypeptides. Supposedly, a charged arginine faces its hydrophobic lipid core, facilitating polypeptide sliding along YidC's surface. How the membrane barrier to other molecules may be maintained is unclear. Here, we show that the purified and reconstituted E. coli YidC forms an ion-conducting transmembrane pore upon ribosome or ribosome-nascent chain complex (RNC) binding. In contrast to monomeric YidC structures, an AlphaFold parallel YidC dimer model harbors a pore. Experimental evidence for a dimeric assembly comes from our BN-PAGE analysis of native vesicles, fluorescence correlation spectroscopy studies, single-molecule fluorescence photobleaching observations, and crosslinking experiments. In the dimeric model, the conserved arginine and other residues interacting with nascent chains point into the putative pore. This result suggests the possibility of a YidC-assisted insertion mode alternative to the insertase mechanism.
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Affiliation(s)
- Denis G. Knyazev
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Lukas Winter
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Andreas Vogt
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert Ludwig University of Freiburg, 79104 Freiburg, Germany (Y.Ö.); (H.-G.K.)
- Spemann-Graduate School of Biology and Medicine (SGBM), Albert Ludwig University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, Albert Ludwig University of Freiburg, 79104 Freiburg, Germany
| | - Sandra Posch
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Yavuz Öztürk
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert Ludwig University of Freiburg, 79104 Freiburg, Germany (Y.Ö.); (H.-G.K.)
| | - Christine Siligan
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Nikolaus Goessweiner-Mohr
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Nora Hagleitner-Ertugrul
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert Ludwig University of Freiburg, 79104 Freiburg, Germany (Y.Ö.); (H.-G.K.)
- Spemann-Graduate School of Biology and Medicine (SGBM), Albert Ludwig University of Freiburg, 79104 Freiburg, Germany
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria; (D.G.K.); (L.W.); (S.P.); (C.S.); (N.G.-M.); (N.H.-E.)
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3
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Mishra S, van Aalst EJ, Wylie BJ, Brady LJ. Cardiolipin occupancy profiles of YidC paralogs reveal the significance of respective TM2 helix residues in determining paralog-specific phenotypes. Front Mol Biosci 2023; 10:1264454. [PMID: 37867558 PMCID: PMC10588454 DOI: 10.3389/fmolb.2023.1264454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/22/2023] [Indexed: 10/24/2023] Open
Abstract
YidC belongs to an evolutionarily conserved family of insertases, YidC/Oxa1/Alb3, in bacteria, mitochondria, and chloroplasts, respectively. Unlike Gram-negative bacteria, Gram-positives including Streptococcus mutans harbor two paralogs of YidC. The mechanism for paralog-specific phenotypes of bacterial YidC1 versus YidC2 has been partially attributed to the differences in their cytoplasmic domains. However, we previously identified a W138R gain-of-function mutation in the YidC1 transmembrane helix 2. YidC1W138R mostly phenocopied YidC2, yet the mechanism remained unknown. Primary sequence comparison of streptococcal YidCs led us to identify and mutate the YidC1W138 analog, YidC2S152 to W/A, which resulted in a loss of YidC2- and acquisition of YidC1-like phenotype. The predicted lipid-facing side chains of YidC1W138/YidC2S152 led us to propose a role for membrane phospholipids in specific-residue dependent phenotypes of S. mutans YidC paralogs. Cardiolipin (CL), a prevalent phospholipid in the S. mutans cytoplasmic membrane during acid stress, is encoded by a single gene, cls. We show a concerted mechanism for cardiolipin and YidC2 under acid stress based on similarly increased promoter activities and similar elimination phenotypes. Using coarse grain molecular dynamics simulations with the Martini2.2 Forcefield, YidC1 and YidC2 wild-type and mutant interactions with CL were assessed in silico. We observed substantially increased CL interaction in dimeric versus monomeric proteins, and variable CL occupancy in YidC1 and YidC2 mutant constructs that mimicked characteristics of the other wild-type paralog. Hence, paralog-specific amino acid- CL interactions contribute to YidC1 and YidC2-associated phenotypes that can be exchanged by point mutation at positions 138 or 152, respectively.
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Affiliation(s)
- Surabhi Mishra
- Department of Oral Biology, University of Florida, Gainesville, FL, United States
| | - Evan J. van Aalst
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States
| | - Benjamin J. Wylie
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States
| | - L. Jeannine Brady
- Department of Oral Biology, University of Florida, Gainesville, FL, United States
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Myronidi I, Ring A, Wu F, Ljungdahl PO. ER-localized Shr3 is a selective co-translational folding chaperone necessary for amino acid permease biogenesis. J Cell Biol 2023; 222:e202208060. [PMID: 37477900 PMCID: PMC10359922 DOI: 10.1083/jcb.202208060] [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: 08/11/2022] [Revised: 04/16/2023] [Accepted: 06/26/2023] [Indexed: 07/22/2023] Open
Abstract
Proteins with multiple membrane-spanning segments (MS) co-translationally insert into the endoplasmic reticulum (ER) membrane of eukaryotic cells. Shr3, an ER membrane-localized chaperone in Saccharomyces cerevisiae, is required for the functional expression of a family of 18 amino acid permeases (AAP) comprised of 12 MS. We have used comprehensive scanning mutagenesis and deletion analysis of Shr3 combined with a modified split-ubiquitin approach to probe chaperone-substrate interactions in vivo. Shr3 selectively interacts with nested C-terminal AAP truncations in marked contrast to similar truncations of non-Shr3 substrate sugar transporters. Shr3-AAP interactions initiate with the first four MS of AAP and successively strengthen but weaken abruptly when all 12 MS are present. Shr3-AAP interactions are based on structural rather than sequence-specific interactions involving membrane and luminal domains of Shr3. The data align with Shr3 engaging nascent N-terminal chains of AAP, functioning as a scaffold to facilitate folding as translation completes.
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Affiliation(s)
- Ioanna Myronidi
- Department of Molecular Biosciences, The Wenner-Gren Institute, SciLifeLab, Stockholm University, Stockholm, Sweden
| | - Andreas Ring
- Department of Molecular Biosciences, The Wenner-Gren Institute, SciLifeLab, Stockholm University, Stockholm, Sweden
| | - Fei Wu
- Department of Biochemistry and Biophysics, SciLifeLab, Stockholm University, Stockholm, Sweden
| | - Per O. Ljungdahl
- Department of Molecular Biosciences, The Wenner-Gren Institute, SciLifeLab, Stockholm University, Stockholm, Sweden
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5
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Dalbey RE, Kaushik S, Kuhn A. YidC as a potential antibiotic target. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119403. [PMID: 36427551 DOI: 10.1016/j.bbamcr.2022.119403] [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: 08/17/2022] [Revised: 11/16/2022] [Accepted: 11/18/2022] [Indexed: 11/24/2022]
Abstract
The membrane insertase YidC, is an essential bacterial component and functions in the folding and insertion of many membrane proteins during their biogenesis. It is a multispanning protein in the inner (cytoplasmic) membrane of Escherichia coli that binds its substrates in the "greasy slide" through hydrophobic interaction. The hydrophilic part of the substrate transiently localizes in the groove of YidC before it is translocated into the periplasm. The groove, which is flanked by the greasy slide, is within the center of the membrane, and provides a promising target for inhibitors that would block the insertase function of YidC. In addition, since the greasy slide is available for the binding of various substrates, it could also provide a binding site for inhibitory molecules. In this review we discuss in detail the structure and the mechanism of how YidC interacts not only with its substrates, but also with its partner proteins, the SecYEG translocase and the SRP signal recognition particle. Insight into the substrate binding to the YidC catalytic groove is presented. We wind up the review with the idea that the hydrophilic groove would be a potential site for drug binding and the feasibility of YidC-targeted drug development.
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Affiliation(s)
- Ross E Dalbey
- Dept. of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States of America.
| | - Sharbani Kaushik
- Dept. of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States of America
| | - Andreas Kuhn
- Institute of Biology, University of Hohenheim, Stuttgart 70599, Germany.
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6
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Kaushik S, He H, Dalbey RE. Bacterial Signal Peptides- Navigating the Journey of Proteins. Front Physiol 2022; 13:933153. [PMID: 35957980 PMCID: PMC9360617 DOI: 10.3389/fphys.2022.933153] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/21/2022] [Indexed: 11/18/2022] Open
Abstract
In 1971, Blobel proposed the first statement of the Signal Hypothesis which suggested that proteins have amino-terminal sequences that dictate their export and localization in the cell. A cytosolic binding factor was predicted, and later the protein conducting channel was discovered that was proposed in 1975 to align with the large ribosomal tunnel. The 1975 Signal Hypothesis also predicted that proteins targeted to different intracellular membranes would possess distinct signals and integral membrane proteins contained uncleaved signal sequences which initiate translocation of the polypeptide chain. This review summarizes the central role that the signal peptides play as address codes for proteins, their decisive role as targeting factors for delivery to the membrane and their function to activate the translocation machinery for export and membrane protein insertion. After shedding light on the navigation of proteins, the importance of removal of signal peptide and their degradation are addressed. Furthermore, the emerging work on signal peptidases as novel targets for antibiotic development is described.
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7
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Hegde RS, Keenan RJ. The mechanisms of integral membrane protein biogenesis. Nat Rev Mol Cell Biol 2022; 23:107-124. [PMID: 34556847 DOI: 10.1038/s41580-021-00413-2] [Citation(s) in RCA: 84] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2021] [Indexed: 02/08/2023]
Abstract
Roughly one quarter of all genes code for integral membrane proteins that are inserted into the plasma membrane of prokaryotes or the endoplasmic reticulum membrane of eukaryotes. Multiple pathways are used for the targeting and insertion of membrane proteins on the basis of their topological and biophysical characteristics. Multipass membrane proteins span the membrane multiple times and face the additional challenges of intramembrane folding. In many cases, integral membrane proteins require assembly with other proteins to form multi-subunit membrane protein complexes. Recent biochemical and structural analyses have provided considerable clarity regarding the molecular basis of membrane protein targeting and insertion, with tantalizing new insights into the poorly understood processes of multipass membrane protein biogenesis and multi-subunit protein complex assembly.
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Affiliation(s)
- Ramanujan S Hegde
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, UK.
| | - Robert J Keenan
- Gordon Center for Integrative Science, The University of Chicago, Chicago, IL, USA.
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8
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Oswald J, Njenga R, Natriashvili A, Sarmah P, Koch HG. The Dynamic SecYEG Translocon. Front Mol Biosci 2021; 8:664241. [PMID: 33937339 PMCID: PMC8082313 DOI: 10.3389/fmolb.2021.664241] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/24/2021] [Indexed: 12/13/2022] Open
Abstract
The spatial and temporal coordination of protein transport is an essential cornerstone of the bacterial adaptation to different environmental conditions. By adjusting the protein composition of extra-cytosolic compartments, like the inner and outer membranes or the periplasmic space, protein transport mechanisms help shaping protein homeostasis in response to various metabolic cues. The universally conserved SecYEG translocon acts at the center of bacterial protein transport and mediates the translocation of newly synthesized proteins into and across the cytoplasmic membrane. The ability of the SecYEG translocon to transport an enormous variety of different substrates is in part determined by its ability to interact with multiple targeting factors, chaperones and accessory proteins. These interactions are crucial for the assisted passage of newly synthesized proteins from the cytosol into the different bacterial compartments. In this review, we summarize the current knowledge about SecYEG-mediated protein transport, primarily in the model organism Escherichia coli, and describe the dynamic interaction of the SecYEG translocon with its multiple partner proteins. We furthermore highlight how protein transport is regulated and explore recent developments in using the SecYEG translocon as an antimicrobial target.
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Affiliation(s)
- Julia Oswald
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Robert Njenga
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Ana Natriashvili
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Pinku Sarmah
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Hans-Georg Koch
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany
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Jauss B, Petriman NA, Drepper F, Franz L, Sachelaru I, Welte T, Steinberg R, Warscheid B, Koch HG. Noncompetitive binding of PpiD and YidC to the SecYEG translocon expands the global view on the SecYEG interactome in Escherichia coli. J Biol Chem 2019; 294:19167-19183. [PMID: 31699901 DOI: 10.1074/jbc.ra119.010686] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/25/2019] [Indexed: 12/22/2022] Open
Abstract
The SecYEG translocon constitutes the major protein transport channel in bacteria and transfers an enormous variety of different secretory and inner-membrane proteins. The minimal core of the SecYEG translocon consists of three inner-membrane proteins, SecY, SecE, and SecG, which, together with appropriate targeting factors, are sufficient for protein transport in vitro However, in vivo the SecYEG translocon has been shown to associate with multiple partner proteins, likely allowing the SecYEG translocon to process its diverse substrates. To obtain a global view on SecYEG plasticity in Escherichia coli, here we performed a quantitative interaction proteomic analysis, which identified several known SecYEG-interacting proteins, verified the interaction of SecYEG with quality-control proteins, and revealed several previously unknown putative SecYEG-interacting proteins. Surprisingly, we found that the chaperone complex PpiD/YfgM is the most prominent interaction partner of SecYEG. Detailed analyses of the PpiD-SecY interaction by site-directed cross-linking revealed that PpiD and the established SecY partner protein YidC use almost completely-overlapping binding sites on SecY. Both PpiD and YidC contacted the lateral gate, the plug domain, and the periplasmic cavity of SecY. However, quantitative MS and cross-linking analyses revealed that despite having almost identical binding sites, their binding to SecY is noncompetitive. This observation suggests that the SecYEG translocon forms different substrate-independent subassemblies in which SecYEG either associates with YidC or with the PpiD/YfgM complex. In summary, the results of this study indicate that the PpiD/YfgM chaperone complex is a primary interaction partner of the SecYEG translocon.
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Affiliation(s)
- Benjamin Jauss
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Narcis-Adrian Petriman
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Friedel Drepper
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Institute of Biology II, Biochemistry and Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Lisa Franz
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Ilie Sachelaru
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Thomas Welte
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Ruth Steinberg
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Institute of Biology II, Biochemistry and Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
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10
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Steinberg R, Knüpffer L, Origi A, Asti R, Koch HG. Co-translational protein targeting in bacteria. FEMS Microbiol Lett 2019; 365:4966980. [PMID: 29790984 DOI: 10.1093/femsle/fny095] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/09/2018] [Indexed: 01/16/2023] Open
Abstract
About 30% of all bacterial proteins execute their function outside of the cytosol and have to be transported into or across the cytoplasmic membrane. Bacteria use multiple protein transport systems in parallel, but the majority of proteins engage two distinct targeting systems. One is the co-translational targeting by two universally conserved GTPases, the signal recognition particle (SRP) and its receptor FtsY, which deliver inner membrane proteins to either the SecYEG translocon or the YidC insertase for membrane insertion. The other targeting system depends on the ATPase SecA, which targets secretory proteins, i.e. periplasmic and outer membrane proteins, to SecYEG for their subsequent ATP-dependent translocation. While SRP selects its substrates already very early during their synthesis, the recognition of secretory proteins by SecA is believed to occur primarily after translation termination, i.e. post-translationally. In this review we highlight recent progress on how SRP recognizes its substrates at the ribosome and how the fidelity of the targeting reaction to SecYEG is maintained. We furthermore discuss similarities and differences in the SRP-dependent targeting to either SecYEG or YidC and summarize recent results that suggest that some membrane proteins are co-translationally targeted by SecA.
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Affiliation(s)
- Ruth Steinberg
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Lara Knüpffer
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Andrea Origi
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany.,Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestr. 1, Freiburg D-79104, Germany
| | - Rossella Asti
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
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11
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Abstract
ABSTRACT
YidC insertase plays a pivotal role in the membrane integration, folding, and assembly of a number of proteins, including energy-transducing respiratory complexes, both autonomously and in concert with the SecYEG channel in bacteria. The YidC family of proteins is widely conserved in all domains of life, with new members recently identified in the eukaryotic endoplasmic reticulum membrane. Bacterial and organellar members share the conserved 5-transmembrane core, which forms a unique hydrophilic cavity in the inner leaflet of the bilayer accessible from the cytoplasm and the lipid phase. In this chapter, we discuss the YidC family of proteins, focusing on its mechanism of substrate insertion independently and in association with the Sec translocon.
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12
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Proctor MS, Chidgey JW, Shukla MK, Jackson PJ, Sobotka R, Hunter CN, Hitchcock A. Plant and algal chlorophyll synthases function in Synechocystis and interact with the YidC/Alb3 membrane insertase. FEBS Lett 2018; 592:3062-3073. [PMID: 30107031 PMCID: PMC6175206 DOI: 10.1002/1873-3468.13222] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 01/17/2023]
Abstract
In the model cyanobacterium Synechocystis sp. PCC 6803, the terminal enzyme of chlorophyll biosynthesis, chlorophyll synthase (ChlG), forms a complex with high light‐inducible proteins, the photosystem II assembly factor Ycf39 and the YidC/Alb3/OxaI membrane insertase, co‐ordinating chlorophyll delivery with cotranslational insertion of nascent photosystem polypeptides into the membrane. To gain insight into the ubiquity of this assembly complex in higher photosynthetic organisms, we produced functional foreign chlorophyll synthases in a cyanobacterial host. Synthesis of algal and plant chlorophyll synthases allowed deletion of the otherwise essential native cyanobacterial gene. Analysis of purified protein complexes shows that the interaction with YidC is maintained for both eukaryotic enzymes, indicating that a ChlG‐YidC/Alb3 complex may be evolutionarily conserved in algae and plants.
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Affiliation(s)
- Matthew S. Proctor
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldUK
| | - Jack W. Chidgey
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldUK
| | - Mahendra K. Shukla
- Institute of MicrobiologyCzech Academy of SciencesCenter AlgatechTřeboňCzech Republic
- Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
| | - Philip J. Jackson
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldUK
- Department of Chemical and Biological EngineeringChELSI InstituteUniversity of SheffieldUK
| | - Roman Sobotka
- Institute of MicrobiologyCzech Academy of SciencesCenter AlgatechTřeboňCzech Republic
- Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
| | - C. Neil Hunter
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldUK
| | - Andrew Hitchcock
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldUK
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13
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Desvaux M, Candela T, Serror P. Surfaceome and Proteosurfaceome in Parietal Monoderm Bacteria: Focus on Protein Cell-Surface Display. Front Microbiol 2018; 9:100. [PMID: 29491848 PMCID: PMC5817068 DOI: 10.3389/fmicb.2018.00100] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 01/16/2018] [Indexed: 12/12/2022] Open
Abstract
The cell envelope of parietal monoderm bacteria (archetypal Gram-positive bacteria) is formed of a cytoplasmic membrane (CM) and a cell wall (CW). While the CM is composed of phospholipids, the CW is composed at least of peptidoglycan (PG) covalently linked to other biopolymers, such as teichoic acids, polysaccharides, and/or polyglutamate. Considering the CW is a porous structure with low selective permeability contrary to the CM, the bacterial cell surface hugs the molecular figure of the CW components as a well of the external side of the CM. While the surfaceome corresponds to the totality of the molecules found at the bacterial cell surface, the proteinaceous complement of the surfaceome is the proteosurfaceome. Once translocated across the CM, secreted proteins can either be released in the extracellular milieu or exposed at the cell surface by associating to the CM or the CW. Following the gene ontology (GO) for cellular components, cell-surface proteins at the CM can either be integral (GO: 0031226), i.e., the integral membrane proteins, or anchored to the membrane (GO: 0046658), i.e., the lipoproteins. At the CW (GO: 0009275), cell-surface proteins can be covalently bound, i.e., the LPXTG-proteins, or bound through weak interactions to the PG or wall polysaccharides, i.e., the cell wall binding proteins. Besides monopolypeptides, some proteins can associate to each other to form supramolecular protein structures of high molecular weight, namely the S-layer, pili, flagella, and cellulosomes. After reviewing the cell envelope components and the different molecular mechanisms involved in protein attachment to the cell envelope, perspectives in investigating the proteosurfaceome in parietal monoderm bacteria are further discussed.
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Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRA, UMR454 MEDiS, Clermont-Ferrand, France
| | - Thomas Candela
- EA4043 Unité Bactéries Pathogènes et Santé, Châtenay-Malabry, France
| | - Pascale Serror
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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14
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Petriman NA, Jauß B, Hufnagel A, Franz L, Sachelaru I, Drepper F, Warscheid B, Koch HG. The interaction network of the YidC insertase with the SecYEG translocon, SRP and the SRP receptor FtsY. Sci Rep 2018; 8:578. [PMID: 29330529 PMCID: PMC5766551 DOI: 10.1038/s41598-017-19019-w] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/20/2017] [Indexed: 12/26/2022] Open
Abstract
YidC/Oxa1/Alb3 are essential proteins that operate independently or cooperatively with the Sec machinery during membrane protein insertion in bacteria, archaea and eukaryotic organelles. Although the interaction between the bacterial SecYEG translocon and YidC has been observed in multiple studies, it is still unknown which domains of YidC are in contact with the SecYEG translocon. By in vivo and in vitro site-directed and para-formaldehyde cross-linking we identified the auxiliary transmembrane domain 1 of E. coli YidC as a major contact site for SecY and SecG. Additional SecY contacts were observed for the tightly packed globular domain and the C1 loop of YidC, which reveals that the hydrophilic cavity of YidC faces the lateral gate of SecY. Surprisingly, YidC-SecYEG contacts were only observed when YidC and SecYEG were present at about stoichiometric concentrations, suggesting that the YidC-SecYEG contact in vivo is either very transient or only observed for a very small SecYEG sub-population. This is different for the YidC-SRP and YidC-FtsY interaction, which involves the C1 loop of YidC and is efficiently observed even at sub-stoichiometric concentrations of SRP/FtsY. In summary, our data provide a first detailed view on how YidC interacts with the SecYEG translocon and the SRP-targeting machinery.
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Affiliation(s)
- Narcis-Adrian Petriman
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Benjamin Jauß
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Antonia Hufnagel
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Lisa Franz
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Ilie Sachelaru
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Friedel Drepper
- Institute of Biology II, Biochemistry - Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Bettina Warscheid
- Institute of Biology II, Biochemistry - Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104, Freiburg, Germany.
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15
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Sachelaru I, Winter L, Knyazev DG, Zimmermann M, Vogt A, Kuttner R, Ollinger N, Siligan C, Pohl P, Koch HG. YidC and SecYEG form a heterotetrameric protein translocation channel. Sci Rep 2017; 7:101. [PMID: 28273911 PMCID: PMC5427846 DOI: 10.1038/s41598-017-00109-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 02/08/2017] [Indexed: 11/26/2022] Open
Abstract
The heterotrimeric SecYEG complex cooperates with YidC to facilitate membrane protein insertion by an unknown mechanism. Here we show that YidC contacts the interior of the SecY channel resulting in a ligand-activated and voltage-dependent complex with distinct ion channel characteristics. The SecYEG pore diameter decreases from 8 Å to only 5 Å for the YidC-SecYEG pore, indicating a reduction in channel cross-section by YidC intercalation. In the presence of a substrate, YidC relocates to the rim of the pore as indicated by increased pore diameter and loss of YidC crosslinks to the channel interior. Changing the surface charge of the pore by incorporating YidC into the channel wall increases the anion selectivity, and the accompanying change in wall hydrophobicity is liable to alter the partition of helices from the pore into the membrane. This could explain how the exit of transmembrane domains from the SecY channel is facilitated by YidC.
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Affiliation(s)
- Ilie Sachelaru
- grid.5963.9Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Stefan Meier Str. 17, Freiburg, 79104 Germany ,grid.5963.9Fakultät für Biologie, Albert-Ludwigs-Universität Freiburg, Stefan Meier Str. 17, 79104 Freiburg, Germany
| | - Lukas Winter
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Denis G. Knyazev
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Mirjam Zimmermann
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Andreas Vogt
- grid.5963.9Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Stefan Meier Str. 17, Freiburg, 79104 Germany ,grid.5963.9Fakultät für Biologie, Albert-Ludwigs-Universität Freiburg, Stefan Meier Str. 17, 79104 Freiburg, Germany ,grid.5963.9Spemann-Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
| | - Roland Kuttner
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Nicole Ollinger
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Christine Siligan
- 0000 0001 1941 5140grid.9970.7Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020 Linz, Austria
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, A-4020, Linz, Austria.
| | - Hans-Georg Koch
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Stefan Meier Str. 17, Freiburg, 79104, Germany. .,Spemann-Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-Universität Freiburg, 79104, Freiburg, Germany.
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16
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Abstract
The insertion and assembly of proteins into the inner membrane of bacteria are crucial for many cellular processes, including cellular respiration, signal transduction, and ion and pH homeostasis. This process requires efficient membrane targeting and insertion of proteins into the lipid bilayer in their correct orientation and proper conformation. Playing center stage in these events are the targeting components, signal recognition particle (SRP) and the SRP receptor FtsY, as well as the insertion components, the Sec translocon and the YidC insertase. Here, we will discuss new insights provided from the recent high-resolution structures of these proteins. In addition, we will review the mechanism by which a variety of proteins with different topologies are inserted into the inner membrane of Gram-negative bacteria. Finally, we report on the energetics of this process and provide information on how membrane insertion occurs in Gram-positive bacteria and Archaea. It should be noted that most of what we know about membrane protein assembly in bacteria is based on studies conducted in Escherichia coli.
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Affiliation(s)
- Andreas Kuhn
- Institute for Microbiology and Molecular Biology, University of Hohenheim, 70599 Stuttgart, Germany
| | - Hans-Georg Koch
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
| | - Ross E Dalbey
- Department of Chemistry, The Ohio State University, Columbus, OH 43210
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17
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Berger I, Jiang Q, Schulze RJ, Collinson I, Schaffitzel C. Multiprotein Complex Production in E. coli: The SecYEG-SecDFYajC-YidC Holotranslocon. Methods Mol Biol 2017; 1586:279-290. [PMID: 28470612 DOI: 10.1007/978-1-4939-6887-9_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A modular approach for balanced overexpression of recombinant multiprotein complexes in E. coli is described, with the prokaryotic protein secretase/insertase complex, the SecYEG-SecDFYajC-YidC holotranslocon (HTL), used as an example. This procedure has been implemented here in the ACEMBL system. The protocol details the design principles of the monocistronic or polycistronic DNA constructs, the expression and purification of functional HTL and its association with translating ribosome nascent chain (RNC) complexes into a RNC-HTL supercomplex.
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Affiliation(s)
- Imre Berger
- The School of Biochemistry, University Walk, University of Bristol, Clifton, BS8 1TD, UK.
- The European Molecular Biology Laboratory (EMBL), and Unit of Virus Host Cell Interactions (UVHCI), BP 181, Polygone Scientifique, 6 Rue Jules Horowitz, 38042, Grenoble Cedex 9, France.
| | - Quiyang Jiang
- The European Molecular Biology Laboratory (EMBL), and Unit of Virus Host Cell Interactions (UVHCI), BP 181, Polygone Scientifique, 6 Rue Jules Horowitz, 38042, Grenoble Cedex 9, France
| | - Ryan J Schulze
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Ian Collinson
- The School of Biochemistry, University Walk, University of Bristol, Clifton, BS8 1TD, UK
| | - Christiane Schaffitzel
- The School of Biochemistry, University Walk, University of Bristol, Clifton, BS8 1TD, UK
- The European Molecular Biology Laboratory (EMBL), and Unit of Virus Host Cell Interactions (UVHCI), BP 181, Polygone Scientifique, 6 Rue Jules Horowitz, 38042, Grenoble Cedex 9, France
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18
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19
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Walter B, Hristou A, Nowaczyk MM, Schünemann D. In vitro reconstitution of co-translational D1 insertion reveals a role of the cpSec-Alb3 translocase and Vipp1 in photosystem II biogenesis. Biochem J 2015; 468:315-24. [PMID: 25803492 DOI: 10.1042/bj20141425] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Photosystem II (PS II) is a multi-subunit complex localized in the thylakoid membrane that performs the light-dependent photosynthetic charge separation. The PS II reaction centre comprises, among others, the D1 protein. De novo synthesis and repair of PS II require efficient mechanisms for transport and insertion of plastid encoded D1 into the thylakoid membrane. To elucidate the process of D1 insertion, we used an in vitro translation system derived from pea chloroplasts to reconstitute the D1 insertion. Thereby, truncated D1 encoding psbA mRNAs lacking a stop codon were translated in the presence of thylakoid membranes and the translation was stalled by addition of chloramphenicol. The generated ribosome nascent chain complexes (RNCs) were tightly associated with the thylakoids. Subsequently, these D1 insertion intermediates were enriched from solubilized thylakoids by sucrose cushion centrifugation. Immunological analyses demonstrated the presence of the cpSec translocase, Alb3, cpFtsY, cpSRP54 and Vipp1 (vesicle-inducing protein in plastids 1) in the enriched D1 insertion intermediates. A complex formation between cpSecY, Alb3, cpFtsY and Vipp1 in thylakoid membranes was shown by gel filtration chromatography, BN (Blue Native)/SDS-PAGE and co-immunoprecipitation experiments. Furthermore, a stimulating effect of recombinant Vipp1 on the formation of a D1 insertion intermediate was observed in vitro. These results suggest a co-operative function of these proteins in D1 insertion.
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Affiliation(s)
- Björn Walter
- *Molecular Biology of Plant Organelles, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Athina Hristou
- *Molecular Biology of Plant Organelles, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Marc M Nowaczyk
- †Plant Biochemistry, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Danja Schünemann
- *Molecular Biology of Plant Organelles, Ruhr-University Bochum, 44780 Bochum, Germany
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20
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Abstract
The YidC/Alb3/Oxa1 family functions in the insertion and folding of proteins in the bacterial cytoplasmic membrane, the chloroplast thylakoid membrane, and the mitochondrial inner membrane. All members share a conserved region composed of five transmembrane regions. These proteins mediate membrane insertion of an assorted group of proteins, ranging from respiratory subunits in the mitochondria and light-harvesting chlorophyll-binding proteins in chloroplasts to ATP synthase subunits in bacteria. This review discusses the YidC/Alb3/Oxa1 protein family as well as their function in membrane insertion and two new structures of the bacterial YidC, which suggest a mechanism for membrane insertion by this family of insertases.
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Affiliation(s)
- Seth W Hennon
- From the Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Raunak Soman
- From the Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Lu Zhu
- From the Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
| | - Ross E Dalbey
- From the Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210
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21
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Komar J, Botte M, Collinson I, Schaffitzel C, Berger I. ACEMBLing a multiprotein transmembrane complex: the functional SecYEG-SecDF-YajC-YidC Holotranslocon protein secretase/insertase. Methods Enzymol 2015; 556:23-49. [PMID: 25857776 DOI: 10.1016/bs.mie.2014.12.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Membrane proteins constitute about one third of the proteome. The ubiquitous Sec machinery facilitates protein movement across or integration of proteins into the cytoplasmic membrane. In Escherichia coli post- and co-translational targeting pathways converge at the protein-conducting channel, consisting of a central pore, SecYEG, which can recruit accessory domains SecDF-YajC and YidC, to form the holotranslocon (HTL) supercomplex. Detailed analysis of HTL function and architecture remained elusive until recently, largely due to the lack of a purified, recombinant complex. ACEMBL is an advanced DNA recombineering-based expression vector system we developed for producing challenging multiprotein complexes. ACEMBL affords the means to combine multiple expression elements including promoter DNAs, tags, genes of interest, and terminators in a combinatorial manner until optimal multigene expression plasmids are constructed that yield correctly assembled, homogenous, and active multiprotein complex specimens. We utilized ACEMBL for recombinant HTL overproduction. We developed protocols for detergent solubilizing and purifying the HTL. Highly purified complex was then used to reveal HTL function and the interactions between its constituents. HTL activity in protein secretion and membrane protein insertion was analyzed in both the presence and absence of the proton-motive force. Setting up ACEMBL for the assembly of multigene expression constructs that achieve high yields of functional multisubunit membrane protein complex is straightforward. Here, we used ACEMBL for obtaining active HTL supercomplex in high quality and quantity. The concept can likewise be applied to obtain many other assemblies of similar complexity, by overexpression in prokaryotic, and also eukaryotic hosts.
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Affiliation(s)
- Joanna Komar
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Mathieu Botte
- European Molecular Biology Laboratory, Grenoble, France; Unit for Virus Host-Cell Interactions, University of Grenoble Alpes-EMBL-CNRS, Unité mixte de Recherche, Grenoble, France
| | - Ian Collinson
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Christiane Schaffitzel
- School of Biochemistry, University of Bristol, Bristol, United Kingdom; European Molecular Biology Laboratory, Grenoble, France; Unit for Virus Host-Cell Interactions, University of Grenoble Alpes-EMBL-CNRS, Unité mixte de Recherche, Grenoble, France
| | - Imre Berger
- School of Biochemistry, University of Bristol, Bristol, United Kingdom; European Molecular Biology Laboratory, Grenoble, France; Unit for Virus Host-Cell Interactions, University of Grenoble Alpes-EMBL-CNRS, Unité mixte de Recherche, Grenoble, France.
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22
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The Escherichia coli membrane protein insertase YidC assists in the biogenesis of penicillin binding proteins. J Bacteriol 2015; 197:1444-50. [PMID: 25666136 DOI: 10.1128/jb.02556-14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Membrane proteins need to be properly inserted and folded in the membrane in order to perform a range of activities that are essential for the survival of bacteria. The Sec translocon and the YidC insertase are responsible for the insertion of the majority of proteins into the cytoplasmic membrane. YidC can act in combination with the Sec translocon in the insertion and folding of membrane proteins. However, YidC also functions as an insertase independently of the Sec translocon for so-called YidC-only substrates. In addition, YidC can act as a foldase and promote the proper assembly of membrane protein complexes. Here, we investigate the effect of Escherichia coli YidC depletion on the assembly of penicillin binding proteins (PBPs), which are involved in cell wall synthesis. YidC depletion does not affect the total amount of the specific cell division PBP3 (FtsI) in the membrane, but the amount of active PBP3, as assessed by substrate binding, is reduced 2-fold. A similar reduction in the amount of active PBP2 was observed, while the levels of active PBP1A/1B and PBP5 were essentially similar. PBP1B and PBP3 disappeared from higher-Mw bands upon YidC depletion, indicating that YidC might play a role in PBP complex formation. Taken together, our results suggest that the foldase activity of YidC can extend to the periplasmic domains of membrane proteins. IMPORTANCE This study addresses the role of the membrane protein insertase YidC in the biogenesis of penicillin binding proteins (PBPs). PBPs are proteins containing one transmembrane segment and a large periplasmic or extracellular domain, which are involved in peptidoglycan synthesis. We observe that in the absence of YidC, two critical PBPs are not correctly folded even though the total amount of protein in the membrane is not affected. Our findings extend the function of YidC as a foldase for membrane protein (complexes) to periplasmic domains of membrane proteins.
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23
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Lewis NE, Brady LJ. Breaking the bacterial protein targeting and translocation model: oral organisms as a case in point. Mol Oral Microbiol 2014; 30:186-97. [PMID: 25400073 DOI: 10.1111/omi.12088] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2014] [Indexed: 12/19/2022]
Abstract
Insights into the membrane biogenesis of oral and throat bacteria have highlighted key differences in protein localization by the general secretion pathway compared with the well-studied Escherichia coli model system. These intriguing novelties have advanced our understanding of both how these microorganisms have adapted to survive and cause disease in the oral cavity, and the field of protein translocation as a whole. This review focuses on findings that highlight where oral bacteria differ from the E. coli paradigm, why these differences are biologically important, and what questions remain about the differences in pathway function. The majority of insight into protein translocation in microbes of the oral cavity has come from streptococcal species, which will be the main topic of this review. However, other bacteria will be discussed when relevant. An overview of the E. coli model of protein targeting and translocation is provided for comparison.
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Affiliation(s)
- N E Lewis
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
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24
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Folding energetics and oligomerization of polytopic α-helical transmembrane proteins. Arch Biochem Biophys 2014; 564:281-96. [DOI: 10.1016/j.abb.2014.07.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 06/26/2014] [Accepted: 07/14/2014] [Indexed: 01/06/2023]
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25
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Glycolipozyme membrane protein integrase (MPIase): recent data. Biomol Concepts 2014; 5:429-38. [DOI: 10.1515/bmc-2014-0030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 09/04/2014] [Indexed: 11/15/2022] Open
Abstract
AbstractA novel factor for membrane protein integration, from the cytoplasmic membrane of Escherichia coli, named MPIase (membrane protein integrase), has recently been identified and characterized. MPIase was revealed to be essential for the membrane integration of a subset of membrane proteins, despite that such integration reactions have been, thus far, thought to occur spontaneously. The structure determination study revealed that MPIase is a novel glycolipid comprising a glycan chain with three N-acetylated amino sugars connected to diacylglycerol through a pyrophosphate linker. As MPIase catalyzes membrane protein integration, we propose that MPIase is a glycolipozyme on the basis of its enzyme-like function. The glycan chain exhibits a molecular chaperone-like function by directly interacting with substrate membrane proteins. Moreover, MPIase also affects the dimer structure of SecYEG, a translocon, thereby significantly stimulating preprotein translocation. The molecular mechanisms of MPIase functions will be outlined.
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26
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Sachelaru I, Petriman NA, Kudva R, Koch HG. Dynamic interaction of the sec translocon with the chaperone PpiD. J Biol Chem 2014; 289:21706-15. [PMID: 24951590 DOI: 10.1074/jbc.m114.577916] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Sec translocon constitutes a ubiquitous protein transport channel that consists in bacteria of the three core components: SecY, SecE, and SecG. Additional proteins interact with SecYEG during different stages of protein transport. During targeting, SecYEG interacts with SecA, the SRP receptor, or the ribosome. Protein transport into or across the membrane is then facilitated by the interaction of SecYEG with YidC and the SecDFYajC complex. During protein transport, SecYEG is likely to interact also with the protein quality control machinery, but details about this interaction are missing. By in vivo and in vitro site-directed cross-linking, we show here that the periplasmic chaperone PpiD is located in front of the lateral gate of SecY, through which transmembrane domains exit the SecY channel. The strongest contacts were found to helix 2b of SecY. Blue native PAGE analyses verify the presence of a SecYEG-PpiD complex in native Escherichia coli membranes. The PpiD-SecY interaction was not influenced by the addition of SecA and only weakly influenced by binding of nontranslating ribosomes to SecYEG. In contrast, PpiD lost contact to the lateral gate of SecY during membrane protein insertion. These data identify PpiD as an additional and transient subunit of the bacterial SecYEG translocon. The data furthermore demonstrate the highly modular and versatile composition of the Sec translocon, which is probably essential for its ability to transport a wide range of substrates across membranes in bacteria and eukaryotes.
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Affiliation(s)
- Ilie Sachelaru
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, the Faculty of Biology, and
| | - Narcis-Adrian Petriman
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, the Faculty of Biology, and
| | - Renuka Kudva
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, the Faculty of Biology, and the Spemann-Graduate School of Biology and Medicine, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
| | - Hans-Georg Koch
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, the Spemann-Graduate School of Biology and Medicine, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
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Denks K, Vogt A, Sachelaru I, Petriman NA, Kudva R, Koch HG. The Sec translocon mediated protein transport in prokaryotes and eukaryotes. Mol Membr Biol 2014; 31:58-84. [DOI: 10.3109/09687688.2014.907455] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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28
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Chidgey JW, Linhartová M, Komenda J, Jackson PJ, Dickman MJ, Canniffe DP, Koník P, Pilný J, Hunter CN, Sobotka R. A cyanobacterial chlorophyll synthase-HliD complex associates with the Ycf39 protein and the YidC/Alb3 insertase. THE PLANT CELL 2014; 26:1267-79. [PMID: 24681617 PMCID: PMC4001383 DOI: 10.1105/tpc.114.124495] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Macromolecular membrane assemblies of chlorophyll-protein complexes efficiently harvest and trap light energy for photosynthesis. To investigate the delivery of chlorophylls to the newly synthesized photosystem apoproteins, a terminal enzyme of chlorophyll biosynthesis, chlorophyll synthase (ChlG), was tagged in the cyanobacterium Synechocystis PCC 6803 (Synechocystis) and used as bait in pull-down experiments. We retrieved an enzymatically active complex comprising ChlG and the high-light-inducible protein HliD, which associates with the Ycf39 protein, a putative assembly factor for photosystem II, and with the YidC/Alb3 insertase. 2D electrophoresis and immunoblotting also provided evidence for the presence of SecY and ribosome subunits. The isolated complex contained chlorophyll, chlorophyllide, and carotenoid pigments. Deletion of hliD elevated the level of the ChlG substrate, chlorophyllide, more than 6-fold; HliD is apparently required for assembly of FLAG-ChlG into larger complexes with other proteins such as Ycf39. These data reveal a link between chlorophyll biosynthesis and the Sec/YidC-dependent cotranslational insertion of nascent photosystem polypeptides into membranes. We expect that this close physical linkage coordinates the arrival of pigments and nascent apoproteins to produce photosynthetic pigment-protein complexes with minimal risk of accumulating phototoxic unbound chlorophylls.
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Affiliation(s)
- Jack W. Chidgey
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Markéta Linhartová
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Josef Komenda
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Philip J. Jackson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- ChELSI Institute, Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom
| | - Mark J. Dickman
- ChELSI Institute, Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom
| | - Daniel P. Canniffe
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Peter Koník
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Jan Pilný
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
| | - C. Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- Address correspondence to
| | - Roman Sobotka
- Institute of Microbiology, Academy of Sciences, 37981 Třeboň, Czech Republic
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice, Czech Republic
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Membrane protein insertion and proton-motive-force-dependent secretion through the bacterial holo-translocon SecYEG-SecDF-YajC-YidC. Proc Natl Acad Sci U S A 2014; 111:4844-9. [PMID: 24550475 DOI: 10.1073/pnas.1315901111] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The SecY/61 complex forms the protein-channel component of the ubiquitous protein secretion and membrane protein insertion apparatus. The bacterial version SecYEG interacts with the highly conserved YidC and SecDF-YajC subcomplex, which facilitates translocation into and across the membrane. Together, they form the holo-translocon (HTL), which we have successfully overexpressed and purified. In contrast to the homo-dimeric SecYEG, the HTL is a hetero-dimer composed of single copies of SecYEG and SecDF-YajC-YidC. The activities of the HTL differ from the archetypal SecYEG complex. It is more effective in cotranslational insertion of membrane proteins and the posttranslational secretion of a β-barreled outer-membrane protein driven by SecA and ATP becomes much more dependent on the proton-motive force. The activity of the translocating copy of SecYEG may therefore be modulated by association with different accessory subcomplexes: SecYEG (forming SecYEG dimers) or SecDF-YajC-YidC (forming the HTL). This versatility may provide a means to refine the secretion and insertion capabilities according to the substrate. A similar modularity may also be exploited for the translocation or insertion of a wide range of substrates across and into the endoplasmic reticular and mitochondrial membranes of eukaryotes.
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31
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Identification of YidC residues that define interactions with the Sec Apparatus. J Bacteriol 2013; 196:367-77. [PMID: 24187090 DOI: 10.1128/jb.01095-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In bacteria, a subset of membrane proteins insert into the membrane via the Sec apparatus with the assistance of the widely conserved essential membrane protein insertase YidC. After threading into the SecYEG translocon, transmembrane segments of nascent proteins are thought to exit the translocon via a lateral gate in SecY, where YidC facilitates their transfer into the lipid bilayer. Interactions between YidC and components of the Sec apparatus are critical to its function. The first periplasmic loop of YidC interacts directly with SecF. We sought to identify the regions or residues of YidC that interact with SecY or with additional components of the Sec apparatus other than SecDF. Using a synthetic lethal screen, we identified residues of YidC that, when mutated, led to dependence on SecDF for viability. Each residue identified is highly conserved among YidC homologs; most lie within transmembrane domains. Overexpression of SecY in the presence of two YidC mutants partially rescued viability in the absence of SecDF, suggesting that the corresponding wild-type YidC residues (G355 and M471) participate in interactions, direct or indirect, with SecY. Staphylococcus aureus YidC complemented depletion of YidC, but not of SecDF, in Escherichia coli. G355 of E. coli YidC is invariant in S. aureus YidC, suggesting that this highly conserved glycine serves a conserved function in interactions with SecY. This study demonstrates that transmembrane residues are critical in YidC interactions with the Sec apparatus and provides guidance on YidC residues of interest for future structure-function analyses.
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Aboulwafa M, Saier MH. Lipid dependencies, biogenesis and cytoplasmic micellar forms of integral membrane sugar transport proteins of the bacterial phosphotransferase system. MICROBIOLOGY-SGM 2013; 159:2213-2224. [PMID: 23985145 DOI: 10.1099/mic.0.070953-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Permeases of the prokaryotic phosphoenolpyruvate-sugar phosphotransferase system (PTS) catalyse sugar transport coupled to sugar phosphorylation. The lipid composition of a membrane determines the activities of these enzyme/transporters as well as the degree of coupling of phosphorylation to transport. We have investigated mechanisms of PTS permease biogenesis and identified cytoplasmic (soluble) forms of these integral membrane proteins. We found that the catalytic activities of the soluble forms differ from those of the membrane-embedded forms. Transport via the latter is much more sensitive to lipid composition than to phosphorylation, and some of these enzymes are much more sensitive to the lipid environment than others. While the membrane-embedded PTS permeases are always dimeric, the cytoplasmic forms are micellar, either monomeric or dimeric. Scattered published evidence suggests that other integral membrane proteins also exist in cytoplasmic micellar forms. The possible functions of cytoplasmic PTS permeases in biogenesis, intracellular sugar phosphorylation and permease storage are discussed.
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Affiliation(s)
- Mohammad Aboulwafa
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, Abbasia, Cairo, Egypt.,Department of Molecular Biology, University of California at San Diego, La Jolla, CA 92093-0116, USA
| | - Milton H Saier
- Department of Molecular Biology, University of California at San Diego, La Jolla, CA 92093-0116, USA
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Zhu L, Kaback HR, Dalbey RE. YidC protein, a molecular chaperone for LacY protein folding via the SecYEG protein machinery. J Biol Chem 2013; 288:28180-94. [PMID: 23928306 DOI: 10.1074/jbc.m113.491613] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
To understand how YidC and SecYEG function together in membrane protein topogenesis, insertion and folding of the lactose permease of Escherichia coli (LacY), a 12-transmembrane helix protein LacY that catalyzes symport of a galactoside and an H(+), was studied. Although both the SecYEG machinery and signal recognition particle are required for insertion of LacY into the membrane, YidC is not required for translocation of the six periplasmic loops in LacY. Rather, YidC acts as a chaperone, facilitating LacY folding. Upon YidC depletion, the conformation of LacY is perturbed, as judged by monoclonal antibody binding studies and by in vivo cross-linking between introduced Cys pairs. Disulfide cross-linking also demonstrates that YidC interacts with multiple transmembrane segments of LacY during membrane biogenesis. Moreover, YidC is strictly required for insertion of M13 procoat protein fused into the middle cytoplasmic loop of LacY. In contrast, the loops preceding and following the inserted procoat domain are dependent on SecYEG for insertion. These studies demonstrate close cooperation between the two complexes in membrane biogenesis and that YidC functions primarily as a foldase for LacY.
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Affiliation(s)
- Lu Zhu
- From the Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210 and
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34
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Kudva R, Denks K, Kuhn P, Vogt A, Müller M, Koch HG. Protein translocation across the inner membrane of Gram-negative bacteria: the Sec and Tat dependent protein transport pathways. Res Microbiol 2013; 164:505-34. [DOI: 10.1016/j.resmic.2013.03.016] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/11/2013] [Indexed: 11/28/2022]
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MPIase is a glycolipozyme essential for membrane protein integration. Nat Commun 2013; 3:1260. [PMID: 23232390 PMCID: PMC3535364 DOI: 10.1038/ncomms2267] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 11/07/2012] [Indexed: 11/16/2022] Open
Abstract
Protein integration into biological membranes is a vital cellular event for all organisms. We previously reported an integration factor in the inner membrane of Escherichia coli, named MPIase (membrane protein integrase). Here we show that in contrast to previously identified integration factors that are proteins, MPIase is a glycolipid composed of diacylglycerol and a glycan chain of three acetylated aminosugars linked through pyrophosphate. Hydrolytic removal of the lipid moiety gives a soluble product with higher integration activity than that of the original MPIase. This soluble form of MPIase directly interacts with a newborn membrane protein, maintaining its integration-competent structure and allowing its post-translational integration. MPIase actively drives protein integration following chaperoning membrane proteins. We further demonstrate with anti-MPIase antibodies that MPIase is likely involved in integration in vivo. Collectively, our results suggest that MPIase, essential for membrane protein integration, is to our knowledge the first glycolipid with an enzyme-like activity. Proteins are integrated into cellular membranes either co-translationally through Sec/SRP or post-translationally by chaperones. These authors show that an integration-dedicated chaperone in E. coli, MPIase, is a glycolipid and facilitates protein insertion into the inner membrane of the bacterium.
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36
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Sachelaru I, Petriman NA, Kudva R, Kuhn P, Welte T, Knapp B, Drepper F, Warscheid B, Koch HG. YidC occupies the lateral gate of the SecYEG translocon and is sequentially displaced by a nascent membrane protein. J Biol Chem 2013; 288:16295-16307. [PMID: 23609445 DOI: 10.1074/jbc.m112.446583] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Most membrane proteins are co-translationally inserted into the lipid bilayer via the universally conserved SecY complex and they access the lipid phase presumably via a lateral gate in SecY. In bacteria, the lipid transfer of membrane proteins from the SecY channel is assisted by the SecY-associated protein YidC, but details on the SecY-YidC interaction are unknown. By employing an in vivo and in vitro site-directed cross-linking approach, we have mapped the SecY-YidC interface and found YidC in contact with all four transmembrane domains of the lateral gate. This interaction did not require the SecDFYajC complex and was not influenced by SecA binding to SecY. In contrast, ribosomes dissociated the YidC contacts to lateral gate helices 2b and 8. The major contact between YidC and the lateral gate was lost in the presence of ribosome nascent chains and new SecY-YidC contacts appeared. These data demonstrate that the SecY-YidC interaction is influenced by nascent-membrane-induced lateral gate movements.
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Affiliation(s)
- Ilie Sachelaru
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany; Fakultät für Biologie, 79104 Freiburg, Germany
| | - Narcis Adrian Petriman
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany; Fakultät für Biologie, 79104 Freiburg, Germany
| | - Renuka Kudva
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany; Fakultät für Biologie, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), 79104 Freiburg, Germany
| | - Patrick Kuhn
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany; Fakultät für Biologie, 79104 Freiburg, Germany
| | - Thomas Welte
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany
| | | | - Friedel Drepper
- Fakultät für Biologie, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Zentrum für Biologische Signalstudien, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- Fakultät für Biologie, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Zentrum für Biologische Signalstudien, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
| | - Hans-Georg Koch
- Institut für Biochemie und Molekularbiologie, ZBMZ, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), 79104 Freiburg, Germany.
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37
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Zhu L, Klenner C, Kuhn A, Dalbey RE. Both YidC and SecYEG Are Required for Translocation of the Periplasmic Loops 1 and 2 of the Multispanning Membrane Protein TatC. J Mol Biol 2012; 424:354-67. [DOI: 10.1016/j.jmb.2012.09.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 09/28/2012] [Accepted: 09/29/2012] [Indexed: 10/27/2022]
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Dalbey RE, Kuhn A. Protein Traffic in Gram-negative bacteria – how exported and secreted proteins find their way. FEMS Microbiol Rev 2012; 36:1023-45. [DOI: 10.1111/j.1574-6976.2012.00327.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 01/04/2012] [Indexed: 11/27/2022] Open
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Prediction of Lipid-Binding Regions in Cytoplasmic and Extracellular Loops of Membrane Proteins as Exemplified by Protein Translocation Membrane Proteins. J Membr Biol 2012; 246:21-9. [DOI: 10.1007/s00232-012-9498-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Accepted: 08/18/2012] [Indexed: 02/07/2023]
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40
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Celedon JM, Cline K. Intra-plastid protein trafficking: how plant cells adapted prokaryotic mechanisms to the eukaryotic condition. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:341-51. [PMID: 22750312 DOI: 10.1016/j.bbamcr.2012.06.028] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 06/11/2012] [Accepted: 06/20/2012] [Indexed: 12/14/2022]
Abstract
Protein trafficking and localization in plastids involve a complex interplay between ancient (prokaryotic) and novel (eukaryotic) translocases and targeting machineries. During evolution, ancient systems acquired new functions and novel translocation machineries were developed to facilitate the correct localization of nuclear encoded proteins targeted to the chloroplast. Because of its post-translational nature, targeting and integration of membrane proteins posed the biggest challenge to the organelle to avoid aggregation in the aqueous compartments. Soluble proteins faced a different kind of problem since some had to be transported across three membranes to reach their destination. Early studies suggested that chloroplasts addressed these issues by adapting ancient-prokaryotic machineries and integrating them with novel-eukaryotic systems, a process called 'conservative sorting'. In the last decade, detailed biochemical, genetic, and structural studies have unraveled the mechanisms of protein targeting and localization in chloroplasts, suggesting a highly integrated scheme where ancient and novel systems collaborate at different stages of the process. In this review we focus on the differences and similarities between chloroplast ancestral translocases and their prokaryotic relatives to highlight known modifications that adapted them to the eukaryotic situation. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.
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Affiliation(s)
- Jose M Celedon
- Horticultural Sciences Department and Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL 32611, USA
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41
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Nannenga BL, Baneyx F. Folding engineering strategies for efficient membrane protein production in E. coli. Methods Mol Biol 2012; 899:187-202. [PMID: 22735954 DOI: 10.1007/978-1-61779-921-1_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Membrane proteins are notoriously difficult to produce at the high levels required for structural and biochemical characterization. Among the various expression systems used to date, the enteric bacterium Escherichia coli remains one of the best characterized and most versatile. However, membrane protein overexpression in E. coli is often accompanied by toxicity and low yields of functional product. Here, we briefly review the involvement of signal recognition particle, trigger factor, and YidC in α-helical membrane protein biogenesis and describe a set of strains, vectors, and chaperone co-expression plasmids that can lead to significant gains in the production of recombinant membrane proteins in E. coli. Methods to quantify membrane proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis are also provided.
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Affiliation(s)
- Brent L Nannenga
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
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Luirink J, Yu Z, Wagner S, de Gier JW. Biogenesis of inner membrane proteins in Escherichia coli. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:965-76. [PMID: 22201544 DOI: 10.1016/j.bbabio.2011.12.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 12/05/2011] [Accepted: 12/12/2011] [Indexed: 11/26/2022]
Abstract
The inner membrane proteome of the model organism Escherichia coli is composed of inner membrane proteins, lipoproteins and peripherally attached soluble proteins. Our knowledge of the biogenesis of inner membrane proteins is rapidly increasing. This is in particular true for the early steps of biogenesis - protein targeting to and insertion into the membrane. However, our knowledge of inner membrane protein folding and quality control is still fragmentary. Furthering our knowledge in these areas will bring us closer to understand the biogenesis of individual inner membrane proteins in the context of the biogenesis of the inner membrane proteome of Escherichia coli as a whole. This article is part of a Special Issue entitled: Biogenesis/Assembly of Respiratory Enzyme Complexes.
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Affiliation(s)
- Joen Luirink
- Section of Molecular Microbiology, Department of Molecular Cell Biology, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
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43
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Welte T, Kudva R, Kuhn P, Sturm L, Braig D, Müller M, Warscheid B, Drepper F, Koch HG. Promiscuous targeting of polytopic membrane proteins to SecYEG or YidC by the Escherichia coli signal recognition particle. Mol Biol Cell 2011; 23:464-79. [PMID: 22160593 PMCID: PMC3268725 DOI: 10.1091/mbc.e11-07-0590] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The YidC insertase also integrates multispanning membrane proteins that had been considered to be exclusively SecYEG dependent. Only membrane proteins that require SecA can be inserted only via SecYEG. Targeting to YidC is SRP dependent, and the C-terminus of YidC cross-links to SRP, FtsY, and ribosomal subunits. Protein insertion into the bacterial inner membrane is facilitated by SecYEG or YidC. Although SecYEG most likely constitutes the major integration site, small membrane proteins have been shown to integrate via YidC. We show that YidC can also integrate multispanning membrane proteins such as mannitol permease or TatC, which had been considered to be exclusively integrated by SecYEG. Only SecA-dependent multispanning membrane proteins strictly require SecYEG for integration, which suggests that SecA can only interact with the SecYEG translocon, but not with the YidC insertase. Targeting of multispanning membrane proteins to YidC is mediated by signal recognition particle (SRP), and we show by site-directed cross-linking that the C-terminus of YidC is in contact with SRP, the SRP receptor, and ribosomal proteins. These findings indicate that SRP recognizes membrane proteins independent of the downstream integration site and that many membrane proteins can probably use either SecYEG or YidC for integration. Because protein synthesis is much slower than protein transport, the use of YidC as an additional integration site for multispanning membrane proteins may prevent a situation in which the majority of SecYEG complexes are occupied by translating ribosomes during cotranslational insertion, impeding the translocation of secretory proteins.
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Affiliation(s)
- Thomas Welte
- Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany
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Unbalanced charge distribution as a determinant for dependence of a subset of Escherichia coli membrane proteins on the membrane insertase YidC. mBio 2011; 2:mBio.00238-11. [PMID: 22108384 PMCID: PMC3225971 DOI: 10.1128/mbio.00238-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Membrane proteins are involved in numerous essential cell processes, including transport, gene regulation, motility, and metabolism. To function properly, they must be inserted into the membrane and folded correctly. YidC, an essential protein in Escherichia coli with homologues in other bacteria, Archaea, mitochondria, and chloroplasts, functions by incompletely understood mechanisms in the insertion and folding of certain membrane proteins. Using a genome-scale approach, we identified 69 E. coli membrane proteins that, in the absence of YidC, exhibited aberrant localization by microscopy. Further examination of a subset revealed biochemical defects in membrane insertion in the absence of YidC, indicating their dependence on YidC for proper membrane insertion or folding. Membrane proteins possessing an unfavorable distribution of positively charged residues were significantly more likely to depend on YidC for membrane insertion. Correcting the charge distribution of a charge-unbalanced YidC-dependent membrane protein abrogated its requirement for YidC, while perturbing the charge distribution of a charge-balanced YidC-independent membrane protein rendered it YidC dependent, demonstrating that charge distribution can be a necessary and sufficient determinant of YidC dependence. These findings provide insights into a mechanism by which YidC promotes proper membrane protein biogenesis and suggest a critical function of YidC in all organisms and organelles that express it. Biological membranes are fundamental components of cells, providing barriers that enclose the cell and separate compartments. Proteins inserted into biological membranes serve critical functions in molecular transport, molecular partitioning, and other essential cell processes. The mechanisms involved in the insertion of proteins into membranes, however, are incompletely understood. The YidC protein is critical for the insertion of a subset of proteins into membranes across an evolutionarily wide group of organisms. Here we identify a large group of proteins that depend on YidC for membrane insertion in Escherichia coli, and we identify unfavorable distribution of charge as an important determinant of YidC dependence for proper membrane insertion.
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45
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Affiliation(s)
- Ross E. Dalbey
- The Ohio State University, Department of Chemistry, Columbus, Ohio 43210;
| | - Peng Wang
- The Ohio State University, Department of Chemistry, Columbus, Ohio 43210;
| | - Andreas Kuhn
- Institute of Microbiology and Molecular Biology, University of Hohenheim, 70599 Stuttgart, Germany;
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46
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Funes S, Kauff F, van der Sluis EO, Ott M, Herrmann JM. Evolution of YidC/Oxa1/Alb3 insertases: three independent gene duplications followed by functional specialization in bacteria, mitochondria and chloroplasts. Biol Chem 2011; 392:13-9. [PMID: 21194367 DOI: 10.1515/bc.2011.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Members of the YidC/Oxa1/Alb3 protein family facilitate the insertion, folding and assembly of proteins of the inner membranes of bacteria and mitochondria and the thylakoid membrane of plastids. All homologs share a conserved hydrophobic core region comprising five transmembrane domains. On the basis of phylogenetic analyses, six subgroups of the family can be distinguished which presumably arose from three independent gene duplications followed by functional specialization. During evolution of bacteria, mitochondria and chloroplasts, subgroup-specific regions were added to the core domain to facilitate the association with ribosomes or other components contributing to the substrate spectrum of YidC/Oxa1/Alb3 proteins.
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Affiliation(s)
- Soledad Funes
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, Mexico D.F. 04510, Mexico
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47
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Characterization of the consequences of YidC depletion on the inner membrane proteome of E. coli using 2D blue native/SDS-PAGE. J Mol Biol 2011; 409:124-35. [PMID: 21497606 DOI: 10.1016/j.jmb.2011.03.068] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 03/28/2011] [Accepted: 03/28/2011] [Indexed: 11/20/2022]
Abstract
In the bacterium Escherichia coli, the essential inner membrane protein (IMP) YidC assists in the biogenesis of IMPs and IMP complexes. Our current ideas about the function of YidC are based on targeted approaches using only a handful of model IMPs. Proteome-wide approaches are required to further our understanding of the significance of YidC and to find new YidC substrates. Here, using two-dimensional blue native/SDS-PAGE methodology that is suitable for comparative analysis, we have characterized the consequences of YidC depletion for the steady-state levels and oligomeric state of the constituents of the inner membrane proteome. Our analysis showed that (i) YidC depletion reduces the levels of a variety of complexes without changing their composition, (ii) the levels of IMPs containing only soluble domains smaller than 100 amino acids are likely to be reduced upon YidC depletion, whereas the levels of IMPs with at least one soluble domain larger than 100 amino acids do not, and (iii) the levels of a number of proteins with established or putative chaperone activity (HflC, HflK, PpiD, OppA, GroEL and DnaK) are strongly increased in the inner membrane fraction upon YidC depletion. In the absence of YidC, these proteins may assist the folding of sizeable soluble domains of IMPs, thereby supporting their folding and oligomeric assembly. In conclusion, our analysis identifies many new IMPs/IMP complexes that depend on YidC for their biogenesis, responses that accompany depletion of YidC and an IMP characteristic that is associated with YidC dependence.
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48
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Klepsch MM, Persson JO, de Gier JWL. Consequences of the overexpression of a eukaryotic membrane protein, the human KDEL receptor, in Escherichia coli. J Mol Biol 2011; 407:532-42. [PMID: 21316372 PMCID: PMC3069486 DOI: 10.1016/j.jmb.2011.02.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 02/02/2011] [Accepted: 02/02/2011] [Indexed: 02/04/2023]
Abstract
Escherichia coli is the most widely used host for producing membrane proteins. Thus far, to study the consequences of membrane protein overexpression in E. coli, we have focussed on prokaryotic membrane proteins as overexpression targets. Their overexpression results in the saturation of the Sec translocon, which is a protein-conducting channel in the cytoplasmic membrane that mediates both protein translocation and insertion. Saturation of the Sec translocon leads to (i) protein misfolding/aggregation in the cytoplasm, (ii) impaired respiration, and (iii) activation of the Arc response, which leads to inefficient ATP production and the formation of acetate. The overexpression yields of eukaryotic membrane proteins in E. coli are usually much lower than those of prokaryotic ones. This may be due to differences between the consequences of the overexpression of prokaryotic and eukaryotic membrane proteins in E. coli. Therefore, we have now also studied in detail how the overexpression of a eukaryotic membrane protein, the human KDEL receptor, affects E. coli. Surprisingly, the consequences of the overexpression of a prokaryotic and a eukaryotic membrane protein are very similar. Strain engineering and likely also protein engineering can be used to remedy the saturation of the Sec translocon upon overexpression of both prokaryotic and eukaryotic membrane proteins in E. coli.
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Affiliation(s)
- Mirjam M. Klepsch
- Center for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Jan O. Persson
- Department of Mathematics & Statistics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Jan-Willem L. de Gier
- Center for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden
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Jong WSP, ten Hagen-Jongman CM, Ruijter E, Orru RVA, Genevaux P, Luirink J. YidC is involved in the biogenesis of the secreted autotransporter hemoglobin protease. J Biol Chem 2010; 285:39682-90. [PMID: 20959450 DOI: 10.1074/jbc.m110.167650] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Autotransporters (ATs) constitute an important family of virulence factors secreted by Gram-negative bacteria. Following their translocation across the inner membrane (IM), ATs temporarily reside in the periplasmic space after which they are secreted into the extracellular environment. Previous studies have shown that the AT hemoglobin protease (Hbp) of Escherichia coli requires a functional signal recognition particle pathway and Sec translocon for optimal targeting to and translocation across the IM. Here, we analyzed the mode of IM translocation of Hbp in more detail. Using site-directed photocross-linking, we found that the Hbp signal peptide is adjacent to YidC early during biogenesis. Notably, YidC is in part associated with the Sec translocon but has until now primarily been implicated in the biogenesis of IM proteins. In vivo, YidC appeared critical for the biogenesis of the ATs Hbp and EspC. For Hbp, depletion of YidC resulted in the formation of secretion-incompetent intermediates that were sensitive to degradation by the periplasmic protease DegP, indicating that YidC activity affects Hbp biogenesis at a late stage, after translocation across the IM. This is the first demonstration of a role for YidC in the biogenesis of an extracellular protein. We propose that YidC is required for maintenance of the translocation-competent state of certain ATs in the periplasm. The large periplasmic domain of YidC is not critical for this novel functionality as it can be deleted without affecting Hbp biogenesis.
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Affiliation(s)
- Wouter S P Jong
- Section of Molecular Microbiology, Department of Molecular Cell Biology, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
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50
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du Plessis DJF, Nouwen N, Driessen AJM. The Sec translocase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:851-65. [PMID: 20801097 DOI: 10.1016/j.bbamem.2010.08.016] [Citation(s) in RCA: 195] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 08/19/2010] [Accepted: 08/20/2010] [Indexed: 11/18/2022]
Abstract
The vast majority of proteins trafficking across or into the bacterial cytoplasmic membrane occur via the translocon. The translocon consists of the SecYEG complex that forms an evolutionarily conserved heterotrimeric protein-conducting membrane channel that functions in conjunction with a variety of ancillary proteins. For posttranslational protein translocation, the translocon interacts with the cytosolic motor protein SecA that drives the ATP-dependent stepwise translocation of unfolded polypeptides across the membrane. For the cotranslational integration of membrane proteins, the translocon interacts with ribosome-nascent chain complexes and membrane insertion is coupled to polypeptide chain elongation at the ribosome. These processes are assisted by the YidC and SecDF(yajC) complex that transiently interacts with the translocon. This review summarizes our current understanding of the structure-function relationship of the translocon and its interactions with ancillary components during protein translocation and membrane protein insertion. This article is part of a Special Issue entitled Protein translocation across or insertion into membranes.
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Affiliation(s)
- David J F du Plessis
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and the Zernike Institute for Advanced Materials, University of Groningen, 9751NN Haren, The Netherlands
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