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Cimuanga-Mukanya A, Tshibangu-Kabamba E, Kisoko PDJN, Fauzia KA, Tshibangu FM, Wola AT, Kashala PT, Ngoyi DM, Ahuka-Mundeke S, Revathi G, Disashi-Tumba G, Kido Y, Matsumoto T, Akada J, Yamaoka Y. Synergistic effects of novel penicillin-binding protein 1A amino acid substitutions contribute to high-level amoxicillin resistance of Helicobacter pylori. mSphere 2024; 9:e0008924. [PMID: 39087788 DOI: 10.1128/msphere.00089-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/14/2024] [Indexed: 08/02/2024] Open
Abstract
The growing resistance to amoxicillin (AMX)-one of the main antibiotics used in Helicobacter pylori eradication therapy-is an increasing health concern. Several mutations of penicillin-binding protein 1A (PBP1A) are suspected of causing AMX resistance; however, only a limited set of these mutations have been experimentally explored. This study aimed to investigate four PBP1A mutations (i.e., T558S, N562H, T593A, and G595S) carried by strain KIN76, a high-level AMX-resistant clinical H. pylori isolate with an AMX minimal inhibition concentration (MIC) of 2 µg/mL. We transformed a recipient strain 26695 with the DNA containing one to four mutation allele combinations of the pbp1 gene from strain KIN76. Transformants were subjected to genomic exploration and antimicrobial susceptibility testing. The resistance was transformable, and the presence of two to four PBP1A mutations (T558S and N562H, or T593A and G595S), rather than separate single mutations, was necessary to synergistically increase the AMX MIC up to 16-fold compared with the wild-type (WT) strain 26695. An AMX binding assay of PBP1A was performed using these strains, and binding was visualized by chasing Bocillin, a fluorescent penicillin analog. This revealed that all four-mutation allele-transformed strains exhibited decreased affinity to AMX on PBP1A than the WT. Protein structure modeling indicated that functional modifications occur as a result of these amino acid substitutions. This study highlights a new synergistic AMX resistance mechanism and establishes new markers of AMX resistance in H. pylori.IMPORTANCEThe development of resistance to antibiotics, including amoxicillin, is hampering the eradication of Helicobacter pylori infection. The identification of mechanisms driving this resistance is crucial for the development of new therapeutic strategies. We have demonstrated in vitro the synergistic role of novel mutations in the pbp1 gene of H. pylori that is suspected to drive amoxicillin resistance. Also deepening our understanding of amoxicillin resistance mechanisms, this study establishes new molecular markers of amoxicillin resistance that may be useful in molecular-based antibiotic susceptibility testing approaches for clinical practice or epidemiologic investigations.
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Affiliation(s)
- Alain Cimuanga-Mukanya
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita, Japan
- Department of Internal Medicine, Faculty of Medicine, Pharmacy and Public Health, University of Mbujimayi, Mbujimayi, Democratic Republic of Congo
| | - Evariste Tshibangu-Kabamba
- Department of Internal Medicine, Faculty of Medicine, Pharmacy and Public Health, University of Mbujimayi, Mbujimayi, Democratic Republic of Congo
- Department of Virology and Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Patrick de Jesus Ngoma Kisoko
- Department of Internal Medicine, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Kartika Afrida Fauzia
- Research Centre for Preclinical and Clinical Medicine, National Research and Innovation Agency, Cibinong Science Center, West Java, Indonesia
| | - Fabien Mbaya Tshibangu
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita, Japan
- Department of Internal Medicine, Faculty of Medicine, Pharmacy and Public Health, University of Mbujimayi, Mbujimayi, Democratic Republic of Congo
| | - Antoine Tshimpi Wola
- Department of Internal Medicine, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | | | - Dieudonné Mumba Ngoyi
- Department of Parasitology, National Institute of Biomedical Research (INRB), Kinshasa, Democratic Republic of Congo
| | - Steve Ahuka-Mundeke
- Department of Virology, National Institute of Biomedical Research (INRB), Kinshasa, Democratic Republic of Congo
| | - Gunturu Revathi
- Department of Clinical Microbiology, Aga Khan University Hospital, Nairobi, Kenya
| | - Ghislain Disashi-Tumba
- Department of Internal Medicine, Faculty of Medicine, Pharmacy and Public Health, University of Mbujimayi, Mbujimayi, Democratic Republic of Congo
| | - Yasutoshi Kido
- Department of Virology and Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Takashi Matsumoto
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita, Japan
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas, USA
- Research Center for Global and Local Infectious Diseases, Oita University, Yufu, Japan
- Division of Gastroentero-Hepatology, Department of Internal Medicine, Faculty of Medicine-Dr. Soetomo Teaching Hospital, Universitas Airlangga, Surabaya, Indonesia
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2
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Karimova G, Ladant D. Defining Membrane Protein Topology Using pho-lac Reporter Fusions. Methods Mol Biol 2024; 2715:181-195. [PMID: 37930528 DOI: 10.1007/978-1-0716-3445-5_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Experimental determination of membrane protein topology can be achieved using various techniques. Here, we present the pho-lac dual reporter system, a simple, convenient, and reliable tool to analyze the topology of membrane protein in vivo. The system is based on the use of two topological markers with complementary properties: The Escherichia coli β-galactosidase, LacZ, which is active in the cytoplasm, and the E. coli alkaline phosphatase, PhoA, which is active in the bacterial periplasm. Specifically, in this pho-lac gene system, the reporter molecule is a chimera composed of the mature PhoA that is in-frame with the β-galactosidase α-peptide (LacZα). Hence, when targeted to the periplasm, the PhoA-LacZα dual reporter displays high alkaline phosphatase activity but no β-galactosidase activity. Conversely, when located in the cytoplasm, PhoA-LacZα has no phosphatase activity but exhibits high β-galactosidase activity in E. coli cells expressing the α-fragment of LacZ, LacZα (via the α-complementation phenomenon). The dual nature of the PhoA-LacZα reporter allows a simple way to normalize both enzymatic activities to obtain readily interpretable information about the subcellular location of the fusion site between the membrane protein under study and the reporter. In addition, the PhoA-LacZα reporter permits the utilization of dual indicator agar plates to easily discriminate between colonies bearing cytoplasmic fusions, periplasmic fusions, or out-of-frame fusions. In total, the phoA-lacZα fusion reporter approach is a direct and rather inexpensive method to characterize the topology of membrane proteins in vivo.
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Affiliation(s)
- Gouzel Karimova
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Université Paris Cité, Paris, France.
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Université Paris Cité, Paris, France
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3
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Karimova G, Gauliard E, Davi M, Ouellette SP, Ladant D. Protein-Protein Interaction: Bacterial Two Hybrid. Methods Mol Biol 2024; 2715:207-224. [PMID: 37930530 DOI: 10.1007/978-1-0716-3445-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
The bacterial two-hybrid (BACTH, for "Bacterial Adenylate Cyclase-based Two-Hybrid") system is a simple and fast genetic approach to detect and characterize protein-protein interactions in vivo. This system is based on the interaction-mediated reconstitution of a cAMP signaling cascade in Escherichia coli. As BACTH uses a diffusible cAMP messenger molecule, the physical association between the two interacting chimeric proteins can be spatially separated from the transcription activation readout, and therefore, it is possible to analyze protein-protein interactions that occur either in the cytosol or at the inner membrane level as well as those that involve DNA-binding proteins. Moreover, proteins from bacterial origin can be studied in an environment similar (or identical) to their native one. The BACTH system may thus permit a simultaneous functional analysis of the proteins of interest-provided the hybrid proteins retain their activity-and their association state. This chapter describes the principle of the BACTH genetic system and the general procedures to study protein-protein interactions in vivo in E. coli.
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Affiliation(s)
- Gouzel Karimova
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Emilie Gauliard
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
- Université Paris Cité, Cellule Pasteur, Paris, France
| | - Marilyne Davi
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Scot P Ouellette
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France.
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4
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Simoens L, Fijalkowski I, Van Damme P. Exposing the small protein load of bacterial life. FEMS Microbiol Rev 2023; 47:fuad063. [PMID: 38012116 PMCID: PMC10723866 DOI: 10.1093/femsre/fuad063] [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: 05/09/2023] [Revised: 11/10/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023] Open
Abstract
The ever-growing repertoire of genomic techniques continues to expand our understanding of the true diversity and richness of prokaryotic genomes. Riboproteogenomics laid the foundation for dynamic studies of previously overlooked genomic elements. Most strikingly, bacterial genomes were revealed to harbor robust repertoires of small open reading frames (sORFs) encoding a diverse and broadly expressed range of small proteins, or sORF-encoded polypeptides (SEPs). In recent years, continuous efforts led to great improvements in the annotation and characterization of such proteins, yet many challenges remain to fully comprehend the pervasive nature of small proteins and their impact on bacterial biology. In this work, we review the recent developments in the dynamic field of bacterial genome reannotation, catalog the important biological roles carried out by small proteins and identify challenges obstructing the way to full understanding of these elusive proteins.
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Affiliation(s)
- Laure Simoens
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Igor Fijalkowski
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Petra Van Damme
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
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Yokoyama T, Yamagata Y, Honna S, Mizuno S, Katagiri S, Oi R, Nogi T, Hizukuri Y, Akiyama Y. S2P intramembrane protease RseP degrades small membrane proteins and suppresses the cytotoxicity of intrinsic toxin HokB. mBio 2023; 14:e0108623. [PMID: 37409810 PMCID: PMC10470546 DOI: 10.1128/mbio.01086-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 05/25/2023] [Indexed: 07/07/2023] Open
Abstract
The site2-protease (S2P) family of intramembrane proteases (IMPs) is conserved in all kingdoms of life and cleaves transmembrane proteins within the membrane to regulate and maintain various cellular activities. RseP, an Escherichia coli S2P peptidase, is involved in the regulation of gene expression through the regulated cleavage of the two target membrane proteins (RseA and FecR) and in membrane quality control through the proteolytic elimination of remnant signal peptides. RseP is expected to have additional substrates and to be involved in other cellular processes. Recent studies have shown that cells express small membrane proteins (SMPs; single-spanning membrane proteins of approximately 50-100 amino acid residues) with crucial cellular functions. However, little is known about their metabolism, which affects their functions. This study investigated the possible RseP-catalyzed cleavage of E. coli SMPs based on the apparent similarity of the sizes and structures of SMPs to those of remnant signal peptides. We screened SMPs cleaved by RseP in vivo and in vitro and identified 14 SMPs, including HokB, an endogenous toxin that induces persister formation, as potential substrates. We demonstrated that RseP suppresses the cytotoxicity and biological functions of HokB. The identification of several SMPs as novel potential substrates of RseP provides a clue to a comprehensive understanding of the cellular roles of RseP and other S2P peptidases and highlights a novel aspect of the regulation of SMPs. IMPORTANCE Membrane proteins play an important role in cell activity and survival. Thus, understanding their dynamics, including proteolytic degradation, is crucial. E. coli RseP, an S2P family intramembrane protease, cleaves membrane proteins to regulate gene expression in response to environmental changes and to maintain membrane quality. To identify novel substrates of RseP, we screened small membrane proteins (SMPs), a group of proteins that have recently been shown to have diverse cellular functions, and identified 14 potential substrates. We also showed that RseP suppresses the cytotoxicity of the intrinsic toxin, HokB, an SMP that has been reported to induce persister cell formation, by degrading it. These findings provide new insights into the cellular roles of S2P peptidases and the functional regulation of SMPs.
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Affiliation(s)
- Tatsuhiko Yokoyama
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Yutaro Yamagata
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Saisei Honna
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Shinya Mizuno
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Shizuka Katagiri
- Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Japan
| | - Rika Oi
- Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Japan
| | - Terukazu Nogi
- Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Japan
| | - Yohei Hizukuri
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Yoshinori Akiyama
- Institute for Life and Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
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6
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Sheng Q, Liu A, Yang P, Chen Z, Wang P, Sun H, Li C, McMinn A, Chen Y, Zhang Y, Su H, Chen X, Zhang Y. The FilZ Protein Contains a Single PilZ Domain and Facilitates the Swarming Motility of Pseudoalteromonas sp. SM9913. Microorganisms 2023; 11:1566. [PMID: 37375068 DOI: 10.3390/microorganisms11061566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 06/03/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Swarming regulation is complicated in flagellated bacteria, especially those possessing dual flagellar systems. It remains unclear whether and how the movement of the constitutive polar flagellum is regulated during swarming motility of these bacteria. Here, we report the downregulation of polar flagellar motility by the c-di-GMP effector FilZ in the marine sedimentary bacterium Pseudoalteromonas sp. SM9913. Strain SM9913 possesses two flagellar systems, and filZ is located in the lateral flagellar gene cluster. The function of FilZ is negatively controlled by intracellular c-di-GMP. Swarming in strain SM9913 consists of three periods. Deletion and overexpression of filZ revealed that, during the period when strain SM9913 expands quickly, FilZ facilitates swarming. In vitro pull-down and bacterial two-hybrid assays suggested that, in the absence of c-di-GMP, FilZ interacts with the CheW homolog A2230, which may be involved in the chemotactic signal transduction pathway to the polar flagellar motor protein FliMp, to interfere with polar flagellar motility. When bound to c-di-GMP, FilZ loses its ability to interact with A2230. Bioinformatic investigation indicated that filZ-like genes are present in many bacteria with dual flagellar systems. Our findings demonstrate a novel mode of regulation of bacterial swarming motility.
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Affiliation(s)
- Qi Sheng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Ang Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Peiling Yang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Zhuowei Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Peng Wang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life Sciences, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Haining Sun
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Chunyang Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life Sciences, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Andrew McMinn
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life Sciences, Ocean University of China, Qingdao 266100, China
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7005, Australia
| | - Yin Chen
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life Sciences, Ocean University of China, Qingdao 266100, China
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Yuzhong Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life Sciences, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Hainan Su
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xiulan Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Yuqiang Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
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7
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Yadavalli SS, Yuan J. Bacterial Small Membrane Proteins: the Swiss Army Knife of Regulators at the Lipid Bilayer. J Bacteriol 2022; 204:e0034421. [PMID: 34516282 PMCID: PMC8765417 DOI: 10.1128/jb.00344-21] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Small membrane proteins represent a subset of recently discovered small proteins (≤100 amino acids), which are a ubiquitous class of emerging regulators underlying bacterial adaptation to environmental stressors. Until relatively recently, small open reading frames encoding these proteins were not designated genes in genome annotations. Therefore, our understanding of small protein biology was primarily limited to a few candidates associated with previously characterized larger partner proteins. Following the first systematic analyses of small proteins in Escherichia coli over a decade ago, numerous small proteins across different bacteria have been uncovered. An estimated one-third of these newly discovered proteins in E. coli are localized to the cell membrane, where they may interact with distinct groups of membrane proteins, such as signal receptors, transporters, and enzymes, and affect their activities. Recently, there has been considerable progress in functionally characterizing small membrane protein regulators aided by innovative tools adapted specifically to study small proteins. Our review covers prototypical proteins that modulate a broad range of cellular processes, such as transport, signal transduction, stress response, respiration, cell division, sporulation, and membrane stability. Thus, small membrane proteins represent a versatile group of physiology regulators at the membrane and the whole cell. Additionally, small membrane proteins have the potential for clinical applications, where some of the proteins may act as antibacterial agents themselves while others serve as alternative drug targets for the development of novel antimicrobials.
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Affiliation(s)
- Srujana S. Yadavalli
- Waksman Institute of Microbiology, Rutgers University, Piscataway, New Jersey, USA
- Department of Genetics, Rutgers University, Piscataway, New Jersey, USA
| | - Jing Yuan
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
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8
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Ladant D. A Bacterial Two-Hybrid System for In Vivo Assays of Protein-Protein Interactions and Drug Discovery. Methods Mol Biol 2022; 2548:145-167. [PMID: 36151497 DOI: 10.1007/978-1-0716-2581-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The bacterial adenylate cyclase-based two-hybrid (BACTH) system is a robust and simple genetic assay used to monitor protein-protein interactions in vivo. This system is based on functional complementation between two fragments from the catalytic domain of Bordetella pertussis adenylate cyclase (AC) to reconstitute a cyclic AMP (cAMP)-signaling cascade in Escherichia coli. Interactions between two chimeric proteins result in the synthesis of cAMP, which activates the transcription of various catabolite operons, leading to selectable phenotypes. One advantageous feature of this signaling cascade is that the physical association between the two interacting hybrid proteins is spatially separated from the transcriptional activation readout. Consequently, the BACTH system can detect protein-protein interactions occurring at various subcellular localizations. The system has been used to characterize interactions between soluble or membrane proteins of prokaryotic, eukaryotic, or viral origin. The BACTH assay can be used to uncover the region(s), domain(s), or amino acid residue(s) of a protein involved in an interaction with a specific partner. The BACTH system can also be adapted for the high-throughput screening of small molecules able to interfere with protein-protein interactions.
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Affiliation(s)
- Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, CNRS UMR 3528, Institut Pasteur, Paris Cedex 15, France.
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9
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Springstein BL, Nürnberg DJ, Woehle C, Weissenbach J, Theune ML, Helbig AO, Maldener I, Dagan T, Stucken K. Two novel heteropolymer-forming proteins maintain the multicellular shape of the cyanobacterium Anabaena sp. PCC 7120. FEBS J 2020; 288:3197-3216. [PMID: 33205554 DOI: 10.1111/febs.15630] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/29/2020] [Accepted: 11/13/2020] [Indexed: 12/14/2022]
Abstract
Polymerizing and filament-forming proteins are instrumental for numerous cellular processes such as cell division and growth. Their function in stabilization and localization of protein complexes and replicons is achieved by a filamentous structure. Known filamentous proteins assemble into homopolymers consisting of single subunits - for example, MreB and FtsZ in bacteria - or heteropolymers that are composed of two subunits, for example, keratin and α/β tubulin in eukaryotes. Here, we describe two novel coiled-coil-rich proteins (CCRPs) in the filament-forming cyanobacterium Anabaena sp. PCC 7120 (hereafter Anabaena) that assemble into a heteropolymer and function in the maintenance of the Anabaena multicellular shape (termed trichome). The two CCRPs - Alr4504 and Alr4505 (named ZicK and ZacK) - are strictly interdependent for the assembly of protein filaments in vivo and polymerize nucleotide independently in vitro, similar to known intermediate filament (IF) proteins. A ΔzicKΔzacK double mutant is characterized by a zigzagged cell arrangement and hence a loss of the typical linear Anabaena trichome shape. ZicK and ZacK interact with themselves, with each other, with the elongasome protein MreB, the septal junction protein SepJ and the divisome associate septal protein SepI. Our results suggest that ZicK and ZacK function in cooperation with SepJ and MreB to stabilize the Anabaena trichome and are likely essential for the manifestation of the multicellular shape in Anabaena. Our study reveals the presence of filament-forming IF-like proteins whose function is achieved through the formation of heteropolymers in cyanobacteria.
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Affiliation(s)
| | | | | | | | - Marius L Theune
- Institute of General Microbiology, University of Kiel, Germany
| | - Andreas O Helbig
- AG Proteomics & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, Germany
| | - Iris Maldener
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen/Organismic Interactions, University of Tübingen, Germany
| | - Tal Dagan
- Institute of General Microbiology, University of Kiel, Germany
| | - Karina Stucken
- Department of Food Engineering, University of La Serena, Chile
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10
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The Small Toxic Salmonella Protein TimP Targets the Cytoplasmic Membrane and Is Repressed by the Small RNA TimR. mBio 2020; 11:mBio.01659-20. [PMID: 33172998 PMCID: PMC7667032 DOI: 10.1128/mbio.01659-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Next-generation sequencing (NGS) has enabled the revelation of a vast number of genomes from organisms spanning all domains of life. To reduce complexity when new genome sequences are annotated, open reading frames (ORFs) shorter than 50 codons in length are generally omitted. However, it has recently become evident that this procedure sorts away ORFs encoding small proteins of high biological significance. For instance, tailored small protein identification approaches have shown that bacteria encode numerous small proteins with important physiological functions. As the number of predicted small ORFs increase, it becomes important to characterize the corresponding proteins. In this study, we discovered a conserved but previously overlooked small enterobacterial protein. We show that this protein, which we dubbed TimP, is a potent toxin that inhibits bacterial growth by targeting the cell membrane. Toxicity is relieved by a small regulatory RNA, which binds the toxin mRNA to inhibit toxin synthesis. Small proteins are gaining increased attention due to their important functions in major biological processes throughout the domains of life. However, their small size and low sequence conservation make them difficult to identify. It is therefore not surprising that enterobacterial ryfA has escaped identification as a small protein coding gene for nearly 2 decades. Since its identification in 2001, ryfA has been thought to encode a noncoding RNA and has been implicated in biofilm formation in Escherichia coli and pathogenesis in Shigella dysenteriae. Although a recent ribosome profiling study suggested ryfA to be translated, the corresponding protein product was not detected. In this study, we provide evidence that ryfA encodes a small toxic inner membrane protein, TimP, overexpression of which causes cytoplasmic membrane leakage. TimP carries an N-terminal signal sequence, indicating that its membrane localization is Sec-dependent. Expression of TimP is repressed by the small RNA (sRNA) TimR, which base pairs with the timP mRNA to inhibit its translation. In contrast to overexpression, endogenous expression of TimP upon timR deletion permits cell growth, possibly indicating a toxicity-independent function in the bacterial membrane.
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11
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DrpB (YedR) Is a Nonessential Cell Division Protein in Escherichia coli. J Bacteriol 2020; 202:JB.00284-20. [PMID: 32900831 PMCID: PMC7648144 DOI: 10.1128/jb.00284-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/02/2020] [Indexed: 12/11/2022] Open
Abstract
A thorough understanding of bacterial cell division requires identifying and characterizing all of the proteins that participate in this process. Our discovery of DrpB brings us one step closer to this goal in E. coli. We report that the small Escherichia coli membrane protein DrpB (formerly YedR) is involved in cell division. We discovered DrpB in a screen for multicopy suppressors of a ΔftsEX mutation that prevents divisome assembly when cells are plated on low ionic strength medium, such as lysogeny broth without NaCl. Characterization of DrpB revealed that (i) translation initiates at an ATG annotated as codon 22 rather than the GTG annotated as codon 1, (ii) DrpB localizes to the septal ring when cells are grown in medium of low ionic strength but localization is greatly reduced in medium of high ionic strength, (iii) overproduction of DrpB in a ΔftsEX mutant background improves recruitment of the septal peptidoglycan synthase FtsI, implying multicopy suppression works by rescuing septal ring assembly, (iv) a ΔdrpB mutant divides quite normally, but a ΔdrpB ΔdedD double mutant has a strong division and viability defect, albeit only in medium of high ionic strength, and (v) DrpB homologs are found in E. coli and a few closely related enteric bacteria, but not outside this group. In sum, DrpB is a poorly conserved nonessential division protein that improves the efficiency of cytokinesis under suboptimal conditions. Proteins like DrpB are likely to be a widespread feature of the bacterial cell division apparatus, but they are easily overlooked because mutants lack obvious shape defects. IMPORTANCE A thorough understanding of bacterial cell division requires identifying and characterizing all of the proteins that participate in this process. Our discovery of DrpB brings us one step closer to this goal in E. coli.
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Zhang W, Wang Y, Li K, Kwok LY, Liu W, Zhang H. Short communication: Modulation of fatty acid metabolism improves oxygen tolerance of Bifidobacterium animalis ssp. lactis Probio-M8. J Dairy Sci 2020; 103:8791-8795. [PMID: 32861486 DOI: 10.3168/jds.2019-18049] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 04/12/2020] [Indexed: 12/29/2022]
Abstract
Bifidobacterium animalis ssp. lactis Probio-M8 is a potential probiotic strain that was isolated from human milk. Previously, we obtained an oxygen-resistant variant (Probio-M8o) of Probio-M8 by an adaptive evolution strategy. In the present study, a comparative transcriptomic analysis of Probio-M8o and Probio-M8 was carried out to reveal the cellular mechanism of the oxygen-resistant phenotype. Using RNA-seq, 210 and 217 differentially expressed genes were identified in Probio-M8o compared with Probio-M8 after oxygen exposure for 30 and 60 min, respectively. The oxygen treatment upregulated a set of genes that encoded proteins responsible for fatty acid biosynthesis. This observation was in good agreement with the composition change in fatty acids at the biochemical level. Our study showed that the oxygen-resistant phenotype could be related to adaptation of fatty acid metabolism.
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Affiliation(s)
- Wenyi Zhang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China
| | - Yuanchi Wang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China
| | - Kangning Li
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China
| | - Lai-Yu Kwok
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China
| | - Wenjun Liu
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China
| | - Heping Zhang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot 010018, China.
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13
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Springstein BL, Arévalo S, Helbig AO, Herrero A, Stucken K, Flores E, Dagan T. A novel septal protein of multicellular heterocystous cyanobacteria is associated with the divisome. Mol Microbiol 2020; 113:1140-1154. [DOI: 10.1111/mmi.14483] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/03/2020] [Accepted: 02/04/2020] [Indexed: 12/13/2022]
Affiliation(s)
| | - Sergio Arévalo
- Instituto de Bioquímica Vegetal y Fotosíntesis CSIC and Universidad de Sevilla Seville Spain
| | - Andreas O. Helbig
- AG Proteomics & Bioanalytics Institute for Experimental Medicine Christian‐Albrechts‐Universität zu Kiel Kiel Germany
| | - Antonia Herrero
- Instituto de Bioquímica Vegetal y Fotosíntesis CSIC and Universidad de Sevilla Seville Spain
| | - Karina Stucken
- Department of Food Engineering Universidad de La Serena La Serena Chile
| | - Enrique Flores
- Instituto de Bioquímica Vegetal y Fotosíntesis CSIC and Universidad de Sevilla Seville Spain
| | - Tal Dagan
- Institute of General Microbiology Christian‐Albrechts‐Universität zu Kiel Kiel Germany
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Springstein BL, Woehle C, Weissenbach J, Helbig AO, Dagan T, Stucken K. Identification and characterization of novel filament-forming proteins in cyanobacteria. Sci Rep 2020; 10:1894. [PMID: 32024928 PMCID: PMC7002697 DOI: 10.1038/s41598-020-58726-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 01/17/2020] [Indexed: 11/09/2022] Open
Abstract
Filament-forming proteins in bacteria function in stabilization and localization of proteinaceous complexes and replicons; hence they are instrumental for myriad cellular processes such as cell division and growth. Here we present two novel filament-forming proteins in cyanobacteria. Surveying cyanobacterial genomes for coiled-coil-rich proteins (CCRPs) that are predicted as putative filament-forming proteins, we observed a higher proportion of CCRPs in filamentous cyanobacteria in comparison to unicellular cyanobacteria. Using our predictions, we identified nine protein families with putative intermediate filament (IF) properties. Polymerization assays revealed four proteins that formed polymers in vitro and three proteins that formed polymers in vivo. Fm7001 from Fischerella muscicola PCC 7414 polymerized in vitro and formed filaments in vivo in several organisms. Additionally, we identified a tetratricopeptide repeat protein - All4981 - in Anabaena sp. PCC 7120 that polymerized into filaments in vitro and in vivo. All4981 interacts with known cytoskeletal proteins and is indispensable for Anabaena viability. Although it did not form filaments in vitro, Syc2039 from Synechococcus elongatus PCC 7942 assembled into filaments in vivo and a Δsyc2039 mutant was characterized by an impaired cytokinesis. Our results expand the repertoire of known prokaryotic filament-forming CCRPs and demonstrate that cyanobacterial CCRPs are involved in cell morphology, motility, cytokinesis and colony integrity.
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Affiliation(s)
- Benjamin L Springstein
- Institute of General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany.
- Department of Microbiology, Blavatnick Institute, Harvard Medical School, Boston, MA, USA.
| | - Christian Woehle
- Institute of General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
- Max Planck Institute for Plant Breeding Research, Max Planck-Genome-centre Cologne, Cologne, Germany
| | - Julia Weissenbach
- Institute of General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Andreas O Helbig
- Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - Tal Dagan
- Institute of General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - Karina Stucken
- Department of Food Engineering, Universidad de La Serena, La Serena, Chile.
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15
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Large-Scale Analyses of Human Microbiomes Reveal Thousands of Small, Novel Genes. Cell 2019; 178:1245-1259.e14. [PMID: 31402174 DOI: 10.1016/j.cell.2019.07.016] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/06/2019] [Accepted: 07/11/2019] [Indexed: 12/12/2022]
Abstract
Small proteins are traditionally overlooked due to computational and experimental difficulties in detecting them. To systematically identify small proteins, we carried out a comparative genomics study on 1,773 human-associated metagenomes from four different body sites. We describe >4,000 conserved protein families, the majority of which are novel; ∼30% of these protein families are predicted to be secreted or transmembrane. Over 90% of the small protein families have no known domain and almost half are not represented in reference genomes. We identify putative housekeeping, mammalian-specific, defense-related, and protein families that are likely to be horizontally transferred. We provide evidence of transcription and translation for a subset of these families. Our study suggests that small proteins are highly abundant and those of the human microbiome, in particular, may perform diverse functions that have not been previously reported.
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16
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VanOrsdel CE, Kelly JP, Burke BN, Lein CD, Oufiero CE, Sanchez JF, Wimmers LE, Hearn DJ, Abuikhdair FJ, Barnhart KR, Duley ML, Ernst SEG, Kenerson BA, Serafin AJ, Hemm MR. Identifying New Small Proteins in Escherichia coli. Proteomics 2018; 18:e1700064. [PMID: 29645342 PMCID: PMC6001520 DOI: 10.1002/pmic.201700064] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 03/05/2018] [Indexed: 12/11/2022]
Abstract
The number of small proteins (SPs) encoded in the Escherichia coli genome is unknown, as current bioinformatics and biochemical techniques make short gene and small protein identification challenging. One method of small protein identification involves adding an epitope tag to the 3′ end of a short open reading frame (sORF) on the chromosome, with synthesis confirmed by immunoblot assays. In this study, this strategy was used to identify new E. coli small proteins, tagging 80 sORFs in the E. coli genome, and assayed for protein synthesis. The selected sORFs represent diverse sequence characteristics, including degrees of sORF conservation, predicted transmembrane domains, sORF direction with respect to flanking genes, ribosome binding site (RBS) prediction, and ribosome profiling results. Of 80 sORFs, 36 resulted in encoded synthesized proteins—a 45% success rate. Modeling of detected versus non‐detected small proteins analysis showed predictions based on RBS prediction, transcription data, and ribosome profiling had statistically‐significant correlation with protein synthesis; however, there was no correlation between current sORF annotation and protein synthesis. These results suggest substantial numbers of small proteins remain undiscovered in E. coli, and existing bioinformatics techniques must continue to improve to facilitate identification.
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Affiliation(s)
- Caitlin E VanOrsdel
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - John P Kelly
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Brittany N Burke
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Christina D Lein
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | | | - Joseph F Sanchez
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Larry E Wimmers
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - David J Hearn
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Fatimeh J Abuikhdair
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Kathryn R Barnhart
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Michelle L Duley
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Sarah E G Ernst
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Briana A Kenerson
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Aubrey J Serafin
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
| | - Matthew R Hemm
- Department of Biological Sciences, Smith Hall, Towson University, Towson, MD, USA
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17
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Cho S, Choe D, Lee E, Kim SC, Palsson B, Cho BK. High-Level dCas9 Expression Induces Abnormal Cell Morphology in Escherichia coli. ACS Synth Biol 2018; 7:1085-1094. [PMID: 29544049 DOI: 10.1021/acssynbio.7b00462] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Along with functional advances in the use of CRISPR/Cas9 for genome editing, endonuclease-deficient Cas9 (dCas9) has provided a versatile molecular tool for exploring gene functions. In principle, differences in cell phenotypes that result from the RNA-guided modulation of transcription levels by dCas9 are critical for inferring with gene function; however, the effect of intracellular dCas9 expression on bacterial morphology has not been systematically elucidated. Here, we observed unexpected morphological changes in Escherichia coli mediated by dCas9, which were then characterized using RNA sequencing (RNA-Seq) and chromatin immunoprecipitation sequencing (ChIP-Seq). Growth rates were severely decreased, to approximately 50% of those of wild type cells, depending on the expression levels of dCas9. Cell shape was changed to abnormal filamentous morphology, indicating that dCas9 affects bacterial cell division. RNA-Seq revealed that 574 genes were differentially transcribed in the presence of high expression levels of dCas9. Genes associated with cell division were upregulated, which was consistent with the observed atypical morphologies. In contrast, 221 genes were downregulated, and these mostly encoded proteins located in the cell membrane. Further, ChIP-Seq results showed that dCas9 directly binds upstream of 37 genes without single-guide RNA, including fimA, which encodes bacterial fimbriae. These results support the fact that dCas9 has critical effects on cell division as well as inner and outer membrane structure. Thus, to precisely understand gene functions using dCas9-driven transcriptional modulation, the regulation of intracellular levels of dCas9 is pivotal to avoid unexpected morphological changes in E. coli.
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Affiliation(s)
- Suhyung Cho
- Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Donghui Choe
- Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Eunju Lee
- Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Sun Chang Kim
- Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
- Intelligent Synthetic Biology Center, Daejeon 305-701, Republic of Korea
| | - Bernhard Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California 92122, United States
- Department of Pediatrics, University of California San Diego, La Jolla, California 92122, United States
| | - Byung-Kwan Cho
- Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
- Intelligent Synthetic Biology Center, Daejeon 305-701, Republic of Korea
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18
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Karimova G, Gauliard E, Davi M, Ouellette SP, Ladant D. Protein-Protein Interaction: Bacterial Two-Hybrid. Methods Mol Biol 2018; 1615:159-176. [PMID: 28667611 DOI: 10.1007/978-1-4939-7033-9_13] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bacterial two-hybrid (BACTH, for "Bacterial Adenylate Cyclase-Based Two-Hybrid") system is a simple and fast genetic approach to detecting and characterizing protein-protein interactions in vivo. This system is based on the interaction-mediated reconstitution of a cyclic adenosine monophosphate (cAMP) signaling cascade in Escherichia coli. As BACTH uses a diffusible cAMP messenger molecule, the physical association between the two interacting chimeric proteins can be spatially separated from the transcription activation readout, and therefore it is possible to analyze protein-protein interactions that occur either in the cytosol or at the inner membrane level as well as those that involve DNA-binding proteins. Moreover, proteins of bacterial origin can be studied in an environment similar (or identical) to their native one. The BACTH system may thus permit a simultaneous functional analysis of proteins of interest-provided the hybrid proteins retain their activity and their association state. This chapter describes the principle of the BACTH genetic system and the general procedures to study protein-protein interactions in vivo in E. coli.
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Affiliation(s)
- Gouzel Karimova
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 Rue du Dr. Roux, Paris, 75015, France
| | - Emilie Gauliard
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 Rue du Dr. Roux, Paris, 75015, France.,Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France
| | - Marilyne Davi
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 Rue du Dr. Roux, Paris, 75015, France
| | - Scot P Ouellette
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 Rue du Dr. Roux, Paris, 75015, France.
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19
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Olson MG, Goldammer M, Gauliard E, Ladant D, Ouellette SP. A Bacterial Adenylate Cyclase-Based Two-Hybrid System Compatible with Gateway ® Cloning. Methods Mol Biol 2018; 1794:75-96. [PMID: 29855952 PMCID: PMC8315169 DOI: 10.1007/978-1-4939-7871-7_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The bacterial adenylate cyclase two-hybrid system (BACTH) is a genetic approach used to test protein interactions in vivo in E. coli. This system takes advantage of the two catalytic domains of Bordetella pertussis adenylate cyclase (CyaA) toxin, which can be fused separately to proteins of interest. If the proteins of interest interact, then the adenylate cyclase domains will be brought in close proximity to each other, reconstituting cyclic AMP (cAMP) production. Interacting proteins can be both qualitatively and quantitatively assessed by the expression of chromosomal genes of the E. coli lac or mal operon, which are positively regulated by cAMP production. Because cAMP is diffusible, the proteins of interest do not need to interact near the transcriptional machinery. Consequently, both cytosolic and membrane protein-protein interactions can be tested. The BACTH system has recently been modified to be compatible with Gateway® recombinational cloning, BACTHGW. This chapter explains the principle of the BACTH, its Gateway® modified system, and details of the general procedure.
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Affiliation(s)
- Macy G Olson
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Megan Goldammer
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
| | - Emilie Gauliard
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Scot P Ouellette
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA.
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA.
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20
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Duval M, Cossart P. Small bacterial and phagic proteins: an updated view on a rapidly moving field. Curr Opin Microbiol 2017; 39:81-88. [PMID: 29111488 DOI: 10.1016/j.mib.2017.09.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 09/17/2017] [Indexed: 01/21/2023]
Abstract
Small proteins, that is, polypeptides of 50 amino acids (aa) or less, are increasingly recognized as important regulators in bacteria. Secreted or not, their small size make them versatile proteins, involved in a wide range of processes. They may allow bacteria to sense and to respond to stresses, to send signals and communicate, and to modulate infections. Bacteriophages also produce small proteins to influence lysogeny/lysis decisions. In this review, we update the present view on small proteins functions, and discuss their possible applications.
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Affiliation(s)
- Mélodie Duval
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, Paris F-75015, France; Institut National de la Santé et de la Recherche Médicale, U604, Paris F-75015, France; Institut National de la Recherche Agronomique, Unité Sous Contrat 2020, Paris F-75015, France.
| | - Pascale Cossart
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, Paris F-75015, France; Institut National de la Santé et de la Recherche Médicale, U604, Paris F-75015, France; Institut National de la Recherche Agronomique, Unité Sous Contrat 2020, Paris F-75015, France.
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21
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Ouellette SP, Karimova G, Davi M, Ladant D. Analysis of Membrane Protein Interactions with a Bacterial Adenylate Cyclase-Based Two-Hybrid (BACTH) Technique. ACTA ACUST UNITED AC 2017; 118:20.12.1-20.12.24. [PMID: 28369675 DOI: 10.1002/cpmb.36] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The bacterial two-hybrid (BACTH, for "Bacterial Adenylate Cyclase-based Two-Hybrid") technique is a simple and fast genetic approach to analyze protein-protein interactions in vivo. In this system, the proteins of interest are genetically fused to two complementary fragments from the catalytic domain of Bordetella pertussis adenylate cyclase and co-expressed in strains of Escherichia coli deficient in adenylate cyclase. Association of the hybrid proteins restores synthesis of cyclic AMP (cAMP), which then triggers the expression of catabolic operons such as the lactose operon or the maltose regulon. As BACTH uses a cAMP second messenger, the association between the chimeric proteins can take place at a distance from the transcription machinery. This technique is therefore particularly appropriate for studying interactions involving integral-membrane or membrane-associated proteins that may not be soluble in the cytoplasm, and/or that may only associate in the plane of the membrane. This unit describes the basic procedures to characterize protein-protein interactions with the BACTH genetic system and to search for potential partners of known proteins. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Scot P Ouellette
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France.,Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota
| | - Gouzel Karimova
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Marilyne Davi
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, Paris, France
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Abstract
Experimental determination of membrane protein topology can be achieved using various techniques. Here we present the pho-lac dual reporter system, a simple, convenient, and reliable tool to analyze the topology of membrane proteins in vivo. The system is based on the use of two topological markers with complementary properties, the Escherichia coli β-galactosidase LacZ, which is active in the cytoplasm, and the E. coli alkaline phosphatase PhoA, which is active in the bacterial periplasm. Specifically, in this pho-lac gene system, the reporter molecule is a chimera composed of the mature PhoA that is in frame with the β-galactosidase α-peptide, LacZα. Hence, when targeted to the periplasm, the PhoA-LacZα dual reporter displays high alkaline phosphatase activity but no β-galactosidase activity. Conversely, when located in the cytoplasm, PhoA-LacZα has no phosphatase activity but exhibits high β-galactosidase activity in E. coli cells expressing the ω fragment of LacZ, LacZω (via the α-complementation phenomenon). The dual nature of the PhoA-LacZα reporter allows a simple way to normalize both enzymatic activities to obtain readily interpretable information about the subcellular location of the fusion site between the membrane protein under study and the reporter. In addition, the PhoA-LacZα reporter permits utilization of dual-indicator agar plates to easily discriminate between colonies bearing cytoplasmic fusions, periplasmic fusions, or out-of-frame fusions. In total, the phoA-lacZα fusion reporter approach is a straightforward and rather inexpensive method of characterizing the topology of membrane proteins in vivo.
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Affiliation(s)
- Gouzel Karimova
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 rue du Dr. Roux, Paris, 75015, France.
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS, UMR 3528, 28 rue du Dr. Roux, Paris, 75015, France
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23
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Yang X, Jensen SI, Wulff T, Harrison SJ, Long KS. Identification and validation of novel small proteins in Pseudomonas putida. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:966-974. [PMID: 27717237 DOI: 10.1111/1758-2229.12473] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/06/2016] [Accepted: 09/10/2016] [Indexed: 06/06/2023]
Abstract
Small proteins of 50 amino acids or less have been understudied due to difficulties that impede their annotation and detection. In order to obtain information on small open reading frames (sORFs) in Pseudomonas putida, bioinformatic and proteomic approaches were used to identify putative sORFs in the well-characterized strain KT2440. A plasmid-based system was established for sORF validation, enabling expression of C-terminal sequential peptide affinity tagged variants and their detection via protein immunoblotting. Out of 22 tested putative sORFs, the expression of 14 sORFs was confirmed, where all except one are novel. All of the validated sORFs except one are located adjacent to annotated genes on the same strand and three are in close proximity to genes with known functions. These include an ABC transporter operon and the two transcriptional regulators Fis and CysB involved in biofilm formation and cysteine biosynthesis respectively. The work sheds light on the P. putida small proteome and small protein identification, a necessary first step towards gaining insights into their functions and possible evolutionary implications.
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Affiliation(s)
- Xiaochen Yang
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Sheila I Jensen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Tune Wulff
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Scott J Harrison
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Katherine S Long
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
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Ouellette SP, Rueden KJ, AbdelRahman YM, Cox JV, Belland RJ. Identification and Partial Characterization of Potential FtsL and FtsQ Homologs of Chlamydia. Front Microbiol 2015; 6:1264. [PMID: 26617598 PMCID: PMC4643143 DOI: 10.3389/fmicb.2015.01264] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/30/2015] [Indexed: 12/26/2022] Open
Abstract
Chlamydia is amongst the rare bacteria that lack the critical cell division protein FtsZ. By annotation, Chlamydia also lacks several other essential cell division proteins including the FtsLBQ complex that links the early (e.g., FtsZ) and late (e.g., FtsI/Pbp3) components of the division machinery. Here, we report chlamydial FtsL and FtsQ homologs. Ct271 aligned well with Escherichia coli FtsL and shared sequence homology with it, including a predicted leucine-zipper like motif. Based on in silico modeling, we show that Ct764 has structural homology to FtsQ in spite of little sequence similarity. Importantly, ct271/ftsL and ct764/ftsQ are present within all sequenced chlamydial genomes and are expressed during the replicative phase of the chlamydial developmental cycle, two key characteristics for a chlamydial cell division gene. GFP-Ct764 localized to the division septum of dividing transformed chlamydiae, and, importantly, over-expression inhibited chlamydial development. Using a bacterial two-hybrid approach, we show that Ct764 interacted with other components of the chlamydial division apparatus. However, Ct764 was not capable of complementing an E. coli FtsQ depletion strain in spite of its ability to interact with many of the same division proteins as E. coli FtsQ, suggesting that chlamydial FtsQ may function differently. We previously proposed that Chlamydia uses MreB and other rod-shape determining proteins as an alternative system for organizing the division site and its apparatus. Chlamydial FtsL and FtsQ homologs expand the number of identified chlamydial cell division proteins and suggest that Chlamydia has likely kept the late components of the division machinery while substituting the Mre system for the early components.
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Affiliation(s)
- Scot P Ouellette
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota Vermillion, SD, USA
| | - Kelsey J Rueden
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota Vermillion, SD, USA
| | - Yasser M AbdelRahman
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center Memphis, TN, USA ; Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University Cairo, Egypt
| | - John V Cox
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center Memphis, TN, USA
| | - Robert J Belland
- Department of Microbiology, Immunology, and Biochemistry, University of Tennessee Health Science Center Memphis, TN, USA
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Badaluddin NA, Kitakawa M. Escherichia coli inner membrane protein YciB interacts with ZipA that is important for cell division. Genes Cells 2015; 20:956-65. [PMID: 26391555 DOI: 10.1111/gtc.12299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/06/2015] [Indexed: 11/29/2022]
Abstract
Escherichia coli propagates by undergoing cycles of lateral elongation, septum formation, and cell fission at the mid-cell. A large number of genes involved in these processes have been identified, but it is likely that others remain. A deletion mutant of yciB (ΔyciB) is shorter in the cell length compared to wild type and, in contrast, over-expression of yciB causes elongation of the cell. Furthermore, the septum localization of ZipA, an essential protein of cell division, is disturbed in a ΔyciB mutant. Purified YciB protein directly interacted with ZipA, which might indicate that YciB is involved in the cell envelope synthesis directed by ZipA in a PBP3-independent manner.
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Affiliation(s)
- Noor Afiza Badaluddin
- Department of Biology, Faculty of Science, Kobe University, Rokko 1-1, Nada, Kobe 657-8501, Japan
| | - Madoka Kitakawa
- Department of Biology, Faculty of Science, Kobe University, Rokko 1-1, Nada, Kobe 657-8501, Japan
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26
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Bittner LM, Westphal K, Narberhaus F. Conditional Proteolysis of the Membrane Protein YfgM by the FtsH Protease Depends on a Novel N-terminal Degron. J Biol Chem 2015; 290:19367-78. [PMID: 26092727 DOI: 10.1074/jbc.m115.648550] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Indexed: 01/16/2023] Open
Abstract
Regulated proteolysis efficiently and rapidly adapts the bacterial proteome to changing environmental conditions. Many protease substrates contain recognition motifs, so-called degrons, that direct them to the appropriate protease. Here we describe an entirely new degron identified in the cytoplasmic N-terminal end of the membrane-anchored protein YfgM of Escherichia coli. YfgM is stable during exponential growth and degraded in stationary phase by the essential FtsH protease. The alarmone (p)ppGpp, but not the previously described YfgM interactors RcsB and PpiD, influence YfgM degradation. By scanning mutagenesis, we define individual amino acids responsible for turnover of YfgM and find that the degron does not at all comply with the known N-end rule pathway. The YfgM degron is a distinct module that facilitates FtsH-mediated degradation when fused to the N terminus of another monotopic membrane protein but not to that of a cytoplasmic protein. Several lines of evidence suggest that stress-induced degradation of YfgM relieves the response regulator RcsB and thereby permits cellular protection by the Rcs phosphorelay system. On the basis of these and other results in the literature, we propose a model for how the membrane-spanning YfgM protein serves as connector between the stress responses in the periplasm and cytoplasm.
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Affiliation(s)
| | - Kai Westphal
- From Microbial Biology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Franz Narberhaus
- From Microbial Biology, Ruhr University Bochum, 44801 Bochum, Germany
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27
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Weiss DS. Last but not least: new insights into how FtsN triggers constriction duringEscherichia colicell division. Mol Microbiol 2015; 95:903-9. [DOI: 10.1111/mmi.12925] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2015] [Indexed: 11/26/2022]
Affiliation(s)
- David S. Weiss
- Department of Microbiology; Carver College of Medicine; The University of Iowa; Iowa City IA 52242 USA
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28
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Ouellette SP, Gauliard E, Antosová Z, Ladant D. A Gateway(®) -compatible bacterial adenylate cyclase-based two-hybrid system. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:259-267. [PMID: 24983530 DOI: 10.1111/1758-2229.12123] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 10/16/2013] [Indexed: 06/03/2023]
Abstract
The bacterial adenylate cyclase two-hybrid (BACTH) system has been widely used to characterize protein-protein interactions in the prokaryotic world. This system relies on the interaction-mediated reconstitution of adenylate cyclase activity in Escherichia coli by bringing together two complementary fragments of the catalytic domain of the adenylate cyclase toxin of Bordetella pertussis. A limiting factor in performing large-scale two-hybrid interaction screens with full-length open reading frames (ORFs) is the need to clone each ORF individually into the plasmids used to express the hybrid proteins. The Gateway(®) (GW) cloning system (Life Technologies, Grand Island, NY, USA) partially circumvents this limitation, and we describe here modifications to the BACTH system for compatibility with this recombineering technology. We validated and tested the functionality of the BACTH Gateway (BACTHGW ) system using several models of protein-protein interactions, focusing particularly on those involved in bacterial cell division. We further modified the BACTH plasmids to incorporate a transmembrane (TM) segment downstream of the cyclase fragments to permit analysis of extracytoplasmic protein interactions. This approach was also useful to identify putative TM segments and to experimentally validate bioinformatically identified TM domains. The BACTHGW system will prove a useful addition to the study of protein-protein interactions.
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Affiliation(s)
- Scot P Ouellette
- Département de Biologie Structurale et Chimie, Institut Pasteur, Unité de Biochimie des Interactions Macromoléculaires, 28 rue du Dr. Roux, F-75015, Paris, France; CNRS, UMR 3528, 28 rue du Dr. Roux, F-75015, Paris, France
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29
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Abstract
Small proteins, here defined as proteins of 50 amino acids or fewer in the absence of processing, have traditionally been overlooked due to challenges in their annotation and biochemical detection. In the past several years, however, increasing numbers of small proteins have been identified either through the realization that mutations in intergenic regions are actually within unannotated small protein genes or through the discovery that some small, regulatory RNAs encode small proteins. These insights, together with comparative sequence analysis, indicate that tens if not hundreds of small proteins are synthesized in a given organism. This review summarizes what has been learned about the functions of several of these bacterial small proteins, most of which act at the membrane, illustrating the astonishing range of processes in which these small proteins act and suggesting several general conclusions. Important questions for future studies of these overlooked proteins are also discussed.
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Affiliation(s)
- Gisela Storz
- Cell Biology and Metabolism Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-5430;
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