1
|
Ruhland E, Siemers M, Gerst R, Späth F, Vogt LN, Figge MT, Papenfort K, Fröhlich KS. The global RNA-RNA interactome of Klebsiella pneumoniae unveils a small RNA regulator of cell division. Proc Natl Acad Sci U S A 2024; 121:e2317322121. [PMID: 38377209 PMCID: PMC10907235 DOI: 10.1073/pnas.2317322121] [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: 10/09/2023] [Accepted: 01/18/2024] [Indexed: 02/22/2024] Open
Abstract
The ubiquitous RNA chaperone Hfq is involved in the regulation of key biological processes in many species across the bacterial kingdom. In the opportunistic human pathogen Klebsiella pneumoniae, deletion of the hfq gene affects the global transcriptome, virulence, and stress resistance; however, the ligands of the major RNA-binding protein in this species have remained elusive. In this study, we have combined transcriptomic, co-immunoprecipitation, and global RNA interactome analyses to compile an inventory of conserved and species-specific RNAs bound by Hfq and to monitor Hfq-mediated RNA-RNA interactions. In addition to dozens of RNA-RNA pairs, our study revealed an Hfq-dependent small regulatory RNA (sRNA), DinR, which is processed from the 3' terminal portion of dinI mRNA. Transcription of dinI is controlled by the master regulator of the SOS response, LexA. As DinR accumulates in K. pneumoniae in response to DNA damage, the sRNA represses translation of the ftsZ transcript by occupation of the ribosome binding site. Ectopic overexpression of DinR causes depletion of ftsZ mRNA and inhibition of cell division, while deletion of dinR antagonizes cell elongation in the presence of DNA damage. Collectively, our work highlights the important role of RNA-based gene regulation in K. pneumoniae and uncovers the central role of DinR in LexA-controlled division inhibition during the SOS response.
Collapse
Affiliation(s)
- Eric Ruhland
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University, Jena07743, Germany
| | - Malte Siemers
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University, Jena07743, Germany
| | - Ruman Gerst
- Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology–Hans Knöll Institute, Jena07745, Germany
| | - Felix Späth
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
| | - Laura Nicole Vogt
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
| | - Marc Thilo Figge
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University, Jena07743, Germany
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology–Hans Knöll Institute, Jena07745, Germany
| | - Kai Papenfort
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University, Jena07743, Germany
| | - Kathrin Sophie Fröhlich
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University, Jena07743, Germany
- Cluster of Excellence Balance of the Microverse, Friedrich Schiller University, Jena07743, Germany
| |
Collapse
|
2
|
Lin CH, Tsai CH, Chou CC, Wu WF. A Transient π-π or Cation-π Interaction between Degron and Degrader Dual Residues: A Key Step for the Substrate Recognition and Discrimination in the Processive Degradation of SulA by ClpYQ (HslUV) Protease in Escherichia coli. Int J Mol Sci 2023; 24:17353. [PMID: 38139184 PMCID: PMC10743992 DOI: 10.3390/ijms242417353] [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: 11/13/2023] [Revised: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023] Open
Abstract
The Escherichia coli ATP-dependent ClpYQ protease constitutes ClpY ATPase/unfoldase and ClpQ peptidase. The Tyr91st residue within the central pore-I site of ClpY-hexamer is important for unfolding and translocating substrates into the catalytic site of ClpQ. We have identified the degron site (GFIMRP147th) of SulA, a cell-division inhibitor recognized by ClpYQ and that the Phe143rd residue in degron site is necessary for SulA native folded structure. However, the functional association of this degron site with the ClpYQ degrader is unknown. Here, we investigated the molecular insights into substrate recognition and discrimination by the ClpYQ protease. We found that the point mutants ClpYY91FQ, ClpYY91HQ, and ClpYY91WQ, carrying a ring structure at the 91st residue of ClpY, efficiently degraded their natural substrates, evidenced by the suppressed bacterial methyl-methane-sulfonate (MMS) sensitivity, the reduced β-galactosidase activity of cpsB::lacZ, and the lowest amounts of MBP-SulA in both in vivo and in vitro degradation analyses. Alternatively, mimicking the wild-type SulA, SulAF143H, SulAF143K and SulAF143W, harboring a ring structure or a cation side-group in 143rd residue of SulA, were efficiently degraded by ClpYQ in the bacterial cells, also revealing shorter half-lives at 41 °C and higher binding affinities towards ClpY in pull-down assays. Finally, ClpYY91FQ and ClpYY91HQ, were capable of effectively degrading SulAF143H and SulAF143K, highlighting a correspondingly functional interaction between the SulA 143rd and ClpY 91st residues. According to the interchangeable substituted amino acids, our results uniquely indicate that a transient π-π or cation-π interaction between the SulA 143rd and ClpY 91st residues could be aptly gripped between the degron site of substrates and the pore site of proteases (degraders) for substrate recognition and discrimination of the processive degradation.
Collapse
Affiliation(s)
- Chu-Hsuan Lin
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei 10617, Taiwan
| | - Chih-Hsuan Tsai
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701401, Taiwan
| | - Chun-Chi Chou
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei 10617, Taiwan
| | - Whei-Fen Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei 10617, Taiwan
| |
Collapse
|
3
|
Sun D, Liu Y, Peng X, Dong H, Jiang H, Fan X, Feng Y, Sun J, Han K, Gao Q, Niu J, Ding J. ClpP protease modulates bacterial growth, stress response, and bacterial virulence in Brucella abortus. Vet Res 2023; 54:68. [PMID: 37612737 PMCID: PMC10464072 DOI: 10.1186/s13567-023-01200-x] [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: 01/25/2023] [Accepted: 06/20/2023] [Indexed: 08/25/2023] Open
Abstract
The process of intracellular proteolysis through ATP-dependent proteases is a biologically conserved phenomenon. The stress responses and bacterial virulence of various pathogenic bacteria are associated with the ATP-dependent Clp protease. In this study, a Brucella abortus 2308 strain, ΔclpP, was constructed to characterize the function of ClpP peptidase. The growth of the ΔclpP mutant strain was significantly impaired in the TSB medium. The results showed that the ΔclpP mutant was sensitive to acidic pH stress, oxidative stress, high temperature, detergents, high osmotic environment, and iron deficient environment. Additionally, the deletion of clpP significantly affected Brucella virulence in macrophage and mouse infection models. Integrated transcriptomic and proteomic analyses of the ΔclpP strain showed that 1965 genes were significantly affected at the mRNA and/or protein levels. The RNA-seq analysis indicated that the ΔclpP strain exhibited distinct gene expression patterns related to energy production and conversion, cell wall/membrane/envelope biogenesis, carbohydrate transport, and metabolism. The iTRAQ analysis revealed that the differentially expressed proteins primarily participated in amino acid transport and metabolism, energy production and conversion, and secondary metabolites biosynthesis, transport and catabolism. This study provided insights into the preliminary molecular mechanism between Clp protease to bacterial growth, stress response, and bacterial virulence in Brucella strains.
Collapse
Affiliation(s)
- Dongjie Sun
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yufu Liu
- Zhaoqing Institute Biotechnology Co., Ltd., Zhaoqing, China
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Xiaowei Peng
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Hao Dong
- Institute for Laboratory Animal Resources, National Institutes for Food and Drug Control, Beijing, China
| | - Hui Jiang
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xuezheng Fan
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yu Feng
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Jiali Sun
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Kun Han
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiang Gao
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | | | - Jiabo Ding
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
| |
Collapse
|
4
|
Derdouri N, Ginet N, Denis Y, Ansaldi M, Battesti A. The prophage-encoded transcriptional regulator AppY has pleiotropic effects on E. coli physiology. PLoS Genet 2023; 19:e1010672. [PMID: 36930675 PMCID: PMC10057817 DOI: 10.1371/journal.pgen.1010672] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/29/2023] [Accepted: 02/18/2023] [Indexed: 03/18/2023] Open
Abstract
Bacterial genome diversity is influenced by prophages, which are viral genomes integrated into the bacterial chromosome. Most prophage genes are silent but those that are expressed can provide unexpected properties to their host. Using as a model E. coli K-12 that carries 9 defective prophages in its genome, we aimed at highlighting the impact of genes encoded by prophages on host physiology. We focused our work on AppY, a transcriptional regulator encoded on the DLP12 prophage. By performing RNA-Seq experiments, we showed that AppY production modulates the expression of more than 200 genes. Among them, 11 were identified by ChIP-Seq as direct AppY targets. AppY directly and positively regulates several genes involved in the acid stress response including the master regulator gene gadE but also nhaR and gadY, two genes important for biofilm formation. Moreover, AppY indirectly and negatively impacts bacterial motility by favoring the degradation of FlhDC, the master regulator of the flagella biosynthesis. As a consequence of these regulatory effects, AppY increases acid stress resistance and biofilm formation while also causing a strong defect in motility. Our research shed light on the importance to consider the genetic interactions occurring between prophages and bacteria to fully understand bacterial physiology. It also highlights how a prophage-encoded transcriptional regulator integrates in a complex manner into the host regulatory network and how it benefits its host, allowing it to cope with changing environmental conditions.
Collapse
Affiliation(s)
- Naoual Derdouri
- Aix Marseille Université, Centre National de la Recherche Scientifique, Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Nicolas Ginet
- Aix Marseille Université, Centre National de la Recherche Scientifique, Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Yann Denis
- Aix Marseille Université, Centre National de la Recherche Scientifique, Plateforme Transcriptome, Institut de Microbiologie de la Méditerranée-, Marseille, France
| | - Mireille Ansaldi
- Aix Marseille Université, Centre National de la Recherche Scientifique, Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Aurélia Battesti
- Aix Marseille Université, Centre National de la Recherche Scientifique, Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, Marseille, France
- * E-mail:
| |
Collapse
|
5
|
Checkpoints That Regulate Balanced Biosynthesis of Lipopolysaccharide and Its Essentiality in Escherichia coli. Int J Mol Sci 2021; 23:ijms23010189. [PMID: 35008618 PMCID: PMC8745692 DOI: 10.3390/ijms23010189] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/17/2021] [Accepted: 12/22/2021] [Indexed: 12/17/2022] Open
Abstract
The outer membrane (OM) of Gram-negative bacteria, such as Escherichia coli, is essential for their viability. Lipopolysaccharide (LPS) constitutes the major component of OM, providing the permeability barrier, and a tight balance exists between LPS and phospholipids amounts as both of these essential components use a common metabolic precursor. Hence, checkpoints are in place, right from the regulation of the first committed step in LPS biosynthesis mediated by LpxC through its turnover by FtsH and HslUV proteases in coordination with LPS assembly factors LapB and LapC. After the synthesis of LPS on the inner leaflet of the inner membrane (IM), LPS is flipped by the IM-located essential ATP-dependent transporter to the periplasmic face of IM, where it is picked up by the LPS transport complex spanning all three components of the cell envelope for its delivery to OM. MsbA exerts its intrinsic hydrocarbon ruler function as another checkpoint to transport hexa-acylated LPS as compared to underacylated LPS. Additional checkpoints in LPS assembly are: LapB-assisted coupling of LPS synthesis and translocation; cardiolipin presence when LPS is underacylated; the recruitment of RfaH transcriptional factor ensuring the transcription of LPS core biosynthetic genes; and the regulated incorporation of non-stoichiometric modifications, controlled by the stress-responsive RpoE sigma factor, small RNAs and two-component systems.
Collapse
|
6
|
Hsieh FC, Chang LK, Tsai CH, Kuan JE, Wu KF, Wu C, Wu WF. Roles of double-loop (130~159 aa and 175~209 aa) in ClpY(HslU)-I domain for SulA substrate degradation by ClpYQ(HslUV) protease in Escherichia coli. J GEN APPL MICROBIOL 2021; 66:297-306. [PMID: 32435002 DOI: 10.2323/jgam.2019.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
An Escherichia coli ATP-dependent two-component protease, ClpYQ(HslUV), targets the SulA molecule, an SOS induced protein. ClpY recognizes, unfolds and translocates the substrates into the proteolytic site of ClpQ for degradation. ClpY is divided into three domains N, I and C. The N domain is an ATPase; the C domain allows for oligomerization, while the I domain coordinates substrate binding. In the ClpYQ complex, two layer pore sites, pore I and II, are in the center of its hexameric rings. However, the actual roles of two outer-loop (130~159 aa, L1 and 175~209 aa, L2) of the ClpY-I domain for the degradation of SulA are unclear. In this study, with ATP, the MBP-SulA molecule was bound to ClpY oligomer(s). ClpYΔL1 (ClpY deleted of loop 1) oligomers revealed an excessive SulA-binding activity. With ClpQ, it showed increased proteolytic activity for SulA degradation. Yet, ClpYΔL2 formed fewer oligomers that retained less proteolytic activity, but still had increased SulA-binding activity. In contrast, ClpYΔpore I had a lower SulA-binding activity. ClpYΔ pore I ΔL2 showed the lowest SulA-binding activity. In addition, ClpY (Q198L, Q200L), with a double point mutation in loop 2, formed stable oligomers. It also had a subtle increase in SulA-binding activity, but displayed less proteolytic activity. As a result, loop 2 has an effect on ClpY oligomerization, substrate binding and delivery. Loop 1 has a role as a gate, to prevent excessive substrate binding. Thus, accordingly, ClpY permits the formation of SulA-ClpY(6x), with ATP(s), and this complex then docks through ClpQ(6x) for ultimate proteolytic degradation.
Collapse
Affiliation(s)
- Fan-Ching Hsieh
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Lu-Kao Chang
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Chih-Hsuan Tsai
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Jung-En Kuan
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Ke-Feng Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Cindy Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| | - Whei-Fen Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University
| |
Collapse
|
7
|
Regulation of the First Committed Step in Lipopolysaccharide Biosynthesis Catalyzed by LpxC Requires the Essential Protein LapC (YejM) and HslVU Protease. Int J Mol Sci 2020; 21:ijms21239088. [PMID: 33260377 PMCID: PMC7730581 DOI: 10.3390/ijms21239088] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 12/29/2022] Open
Abstract
We previously showed that lipopolysaccharide (LPS) assembly requires the essential LapB protein to regulate FtsH-mediated proteolysis of LpxC protein that catalyzes the first committed step in the LPS synthesis. To further understand the essential function of LapB and its role in LpxC turnover, multicopy suppressors of ΔlapB revealed that overproduction of HslV protease subunit prevents its lethality by proteolytic degradation of LpxC, providing the first alternative pathway of LpxC degradation. Isolation and characterization of an extragenic suppressor mutation that prevents lethality of ΔlapB by restoration of normal LPS synthesis identified a frame-shift mutation after 377 aa in the essential gene designated lapC, suggesting LapB and LapC act antagonistically. The same lapC gene was identified during selection for mutations that induce transcription from LPS defects-responsive rpoEP3 promoter, confer sensitivity to LpxC inhibitor CHIR090 and a temperature-sensitive phenotype. Suppressors of lapC mutants that restored growth at elevated temperatures mapped to lapA/lapB, lpxC and ftsH genes. Such suppressor mutations restored normal levels of LPS and prevented proteolysis of LpxC in lapC mutants. Interestingly, a lapC deletion could be constructed in strains either overproducing LpxC or in the absence of LapB, revealing that FtsH, LapB and LapC together regulate LPS synthesis by controlling LpxC amounts.
Collapse
|
8
|
Zhang SP, Wang Q, Quan SW, Yu XQ, Wang Y, Guo DD, Peng L, Feng HY, He YX. Type II toxin–antitoxin system in bacteria: activation, function, and mode of action. BIOPHYSICS REPORTS 2020. [DOI: 10.1007/s41048-020-00109-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
9
|
Heat-shock proteases promote survival of Pseudomonas aeruginosa during growth arrest. Proc Natl Acad Sci U S A 2020; 117:4358-4367. [PMID: 32029587 DOI: 10.1073/pnas.1912082117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
When nutrients in their environment are exhausted, bacterial cells become arrested for growth. During these periods, a primary challenge is maintaining cellular integrity with a reduced capacity for renewal or repair. Here, we show that the heat-shock protease FtsH is generally required for growth arrest survival of Pseudomonas aeruginosa, and that this requirement is independent of a role in regulating lipopolysaccharide synthesis, as has been suggested for Escherichia coli We find that ftsH interacts with diverse genes during growth and overlaps functionally with the other heat-shock protease-encoding genes hslVU, lon, and clpXP to promote survival during growth arrest. Systematic deletion of the heat-shock protease-encoding genes reveals that the proteases function hierarchically during growth arrest, with FtsH and ClpXP having primary, nonredundant roles, and HslVU and Lon deploying a secondary response to aging stress. This hierarchy is partially conserved during growth at high temperature and alkaline pH, suggesting that heat, pH, and growth arrest effectively impose a similar type of proteostatic stress at the cellular level. In support of this inference, heat and growth arrest act synergistically to kill cells, and protein aggregation appears to occur more rapidly in protease mutants during growth arrest and correlates with the onset of cell death. Our findings suggest that protein aggregation is a major driver of aging and cell death during growth arrest, and that coordinated activity of the heat-shock response is required to ensure ongoing protein quality control in the absence of growth.
Collapse
|
10
|
Kumaran NAM, Karthik M, Kumar V, Jebasingh T, Munavar MH. Two new mutations in dnaJ suppress DNA damage hypersensitivity and capsule overproduction phenotypes of Δlon mutant of Escherichia coli by modulating the expression of clpYQ (hslUV) and rcsA genes. Gene 2020; 726:144135. [DOI: 10.1016/j.gene.2019.144135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/30/2022]
|
11
|
Molecular mechanisms of collateral sensitivity to the antibiotic nitrofurantoin. PLoS Biol 2020; 18:e3000612. [PMID: 31986134 PMCID: PMC7004380 DOI: 10.1371/journal.pbio.3000612] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 02/06/2020] [Accepted: 01/06/2020] [Indexed: 12/20/2022] Open
Abstract
Antibiotic resistance increasingly limits the success of antibiotic treatments, and physicians require new ways to achieve efficient treatment despite resistance. Resistance mechanisms against a specific antibiotic class frequently confer increased susceptibility to other antibiotic classes, a phenomenon designated collateral sensitivity (CS). An informed switch of antibiotic may thus enable the efficient treatment of resistant strains. CS occurs in many pathogens, but the mechanisms that generate hypersusceptibility are largely unknown. We identified several molecular mechanisms of CS against the antibiotic nitrofurantoin (NIT). Mutants that are resistant against tigecycline (tetracycline), mecillinam (β-lactam), and protamine (antimicrobial peptide) all show CS against NIT. Their hypersusceptibility is explained by the overexpression of nitroreductase enzymes combined with increased drug uptake rates, or increased drug toxicity. Increased toxicity occurs through interference of the native drug-response system for NIT, the SOS response, with growth. A mechanistic understanding of CS will help to develop drug switches that combat resistance. Resistance mechanisms against a specific antibiotic class frequently often confer negative cross-resistance to other antibiotic classes, a phenomenon known as collateral sensitivity. This study shows that collateral sensitivity in bacteria can be explained by a combination of several mechanisms that can be exploited to develop drug switches that combat resistance.
Collapse
|
12
|
Eyermann B, Meixner M, Brötz‐Oesterhelt H, Antes I, Sieber SA. Acyldepsipeptide Probes Facilitate Specific Detection of Caseinolytic Protease P Independent of Its Oligomeric and Activity State. Chembiochem 2020; 21:235-240. [PMID: 31487112 PMCID: PMC7003903 DOI: 10.1002/cbic.201900477] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Indexed: 12/21/2022]
Abstract
Caseinolytic protease P (ClpP) is a tetradecameric peptidase that assembles with chaperones such as ClpX to gain proteolytic activity. Acyldepsipeptides (ADEPs) are small-molecule mimics of ClpX that bind into hydrophobic pockets on the apical site of the complex, thereby activating ClpP. Detection of ClpP has so far been facilitated with active-site-directed probes which depend on the activity and oligomeric state of the complex. To expand the scope of ClpP labeling, we took a stepwise synthetic approach toward customized ADEP photoprobes. Structure-activity relationship studies with small fragments and ADEP derivatives paired with modeling studies revealed the design principles for suitable probe molecules. The derivatives were tested for activation of ClpP and subsequently applied in labeling studies of the wild-type peptidase as well as enzymes bearing mutations at the active site and an oligomerization sensor. Satisfyingly, the ADEP photoprobes provided a labeling readout of ClpP independent of its activity and oligomeric state.
Collapse
Affiliation(s)
- Barbara Eyermann
- Department ChemieTechnische Universität MünchenLichtenbergstrasse 485748GarchingGermany
| | - Maximilian Meixner
- Department für BiowissenschaftenTechnische Universität MünchenEmil-Erlenmeyer-Forum 885354FreisingGermany
| | - Heike Brötz‐Oesterhelt
- Interfaculty Institute of Microbiology and Infection MedicineMicrobial Bioactive CompoundsUniversity of TübingenAuf der Morgenstelle 28, E-Bau, Ebene 872076TübingenGermany
| | - Iris Antes
- Department für BiowissenschaftenTechnische Universität MünchenEmil-Erlenmeyer-Forum 885354FreisingGermany
| | - Stephan A. Sieber
- Department ChemieTechnische Universität MünchenLichtenbergstrasse 485748GarchingGermany
| |
Collapse
|
13
|
Bojer MS, Frees D, Ingmer H. SosA in Staphylococci: an addition to the paradigm of membrane-localized, SOS-induced cell division inhibition in bacteria. Curr Genet 2020; 66:495-499. [PMID: 31925496 DOI: 10.1007/s00294-019-01052-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 12/28/2019] [Accepted: 12/31/2019] [Indexed: 12/19/2022]
Abstract
In all living organisms, genome replication and cell division must be coordinated to produce viable offspring. In the event of DNA damage, bacterial cells employ the SOS response to simultaneously express damage repair systems and halt cell division. Extensive characterization of SOS-controlled cell division inhibition in Escherichia coli has laid the ground for a long-standing paradigm where the cytosolic SulA protein inhibits polymerization of the central division protein, FtsZ, and thereby prevents recruitment of the division machinery at the future division site. Within the last decade, it has become clear that another, likely more general, paradigm exists, at least within the broad group of Gram-positive bacterial species, namely membrane-localized, SOS-induced cell division inhibition. We recently identified such an inhibitor in Staphylococci, SosA, and established a model for SosA-mediated cell division inhibition in Staphylococcus aureus in response to DNA damage. SosA arrests cell division subsequent to the septal localization of FtsZ and later membrane-bound division proteins, while preventing progression to septum closure, leading to synchronization of cells at this particular stage. A membrane-associated protease, CtpA negatively regulates SosA activity and likely allows growth to resume once conditions are favorable. Here, we provide a brief summary of our findings in the context of what already is known for other membrane cell division inhibitors and we emphasize how poorly characterized these intriguing processes are mechanistically. Furthermore, we put some perspective on the relevance of our findings and future developments within the field.
Collapse
Affiliation(s)
- Martin S Bojer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dorte Frees
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
14
|
Regulation of Cell Division in Bacteria by Monitoring Genome Integrity and DNA Replication Status. J Bacteriol 2020; 202:JB.00408-19. [PMID: 31548275 DOI: 10.1128/jb.00408-19] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
All organisms regulate cell cycle progression by coordinating cell division with DNA replication status. In eukaryotes, DNA damage or problems with replication fork progression induce the DNA damage response (DDR), causing cyclin-dependent kinases to remain active, preventing further cell cycle progression until replication and repair are complete. In bacteria, cell division is coordinated with chromosome segregation, preventing cell division ring formation over the nucleoid in a process termed nucleoid occlusion. In addition to nucleoid occlusion, bacteria induce the SOS response after replication forks encounter DNA damage or impediments that slow or block their progression. During SOS induction, Escherichia coli expresses a cytoplasmic protein, SulA, that inhibits cell division by directly binding FtsZ. After the SOS response is turned off, SulA is degraded by Lon protease, allowing for cell division to resume. Recently, it has become clear that SulA is restricted to bacteria closely related to E. coli and that most bacteria enforce the DNA damage checkpoint by expressing a small integral membrane protein. Resumption of cell division is then mediated by membrane-bound proteases that cleave the cell division inhibitor. Further, many bacterial cells have mechanisms to inhibit cell division that are regulated independently from the canonical LexA-mediated SOS response. In this review, we discuss several pathways used by bacteria to prevent cell division from occurring when genome instability is detected or before the chromosome has been fully replicated and segregated.
Collapse
|
15
|
He Y, Chen Y, Morris DL, Lee DY, Tjandra N. Bax expression is optimal at low oxygen tension and constant agitation. Protein Expr Purif 2019; 165:105501. [PMID: 31542563 PMCID: PMC6908824 DOI: 10.1016/j.pep.2019.105501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/02/2022]
Abstract
Bax is a pro-apoptosis protein that translocates from the cytosol to the mitochondria membrane upon initiation of programed cell death. Bax subsequently disrupts the mitochondria membrane, resulting in the release of cytochrome C which activates the downstream caspases. The structure of inactive Bax has been solved, but despite intensive investigation, the mechanism by which it regulates apoptosis is not established. The low yield of Bax expression in E. coli hampers efforts to elucidate the mechanism. Thus, we undertook a systematic study aimed at improving the yield of Bax. Bacteria were grown in a computer-controlled fermenter and expression was induced by addition of Isopropyl ß-D-1-thiogalactopyranoside (IPTG). The Bax expression level decreased continuously when the dissolved oxygen level was kept at 30%, which is non-limiting for E. coli. Alternatively, when oxygen input was decreased with constant agitation and air flow (or kLa), Bax yield increased by a factor of three. To make sure the short chain fatty acids generated during micro-aerobic fermentation had no adverse effect, their concentrations were closely monitored with HPLC and their effect on cell growth and Bax expression were investigated additionally using shake flasks. Through proteomic analysis using Tandem Mass Tag (TMT) labeling, we identified degradation pathway within E. coli cells as a potential player behind the lower expression level.
Collapse
Affiliation(s)
- Yi He
- National Institutes of Health, National Heart, Lung and Blood Institute, Biochemistry and Biophysics Center, Bethesda, MD, 20892, USA.
| | - Yong Chen
- National Institutes of Health, National Heart, Lung and Blood Institute, Proteomics Core, Bethesda, MD, 20892, USA
| | - Daniel L Morris
- National Institutes of Health, National Heart, Lung and Blood Institute, Biochemistry and Biophysics Center, Bethesda, MD, 20892, USA
| | - Duck-Yeon Lee
- National Institutes of Health, National Heart, Lung and Blood Institute, Biochemistry Core, Bethesda, MD, 20892, USA
| | - Nico Tjandra
- National Institutes of Health, National Heart, Lung and Blood Institute, Biochemistry and Biophysics Center, Bethesda, MD, 20892, USA
| |
Collapse
|
16
|
Kumaran N, Munavar MH. Suppression of Δlonphenotypes in Escherichia coliby N-terminal DnaK peptides. J Basic Microbiol 2019; 59:302-313. [DOI: 10.1002/jobm.201800469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Nagarajan Kumaran
- Department of Molecular Biology, School of Biological Sciences, Centre for Advanced Studies in Functional and Organismal Genomics; Madurai Kamaraj University; Palkalai Nagar, Madurai Tamil Nadu India
| | - M. Hussain Munavar
- Department of Molecular Biology, School of Biological Sciences, Centre for Advanced Studies in Functional and Organismal Genomics; Madurai Kamaraj University; Palkalai Nagar, Madurai Tamil Nadu India
| |
Collapse
|
17
|
Burby PE, Simmons ZW, Simmons LA. DdcA antagonizes a bacterial DNA damage checkpoint. Mol Microbiol 2019; 111:237-253. [PMID: 30315724 PMCID: PMC6351180 DOI: 10.1111/mmi.14151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2018] [Indexed: 12/15/2022]
Abstract
Bacteria coordinate DNA replication and cell division, ensuring a complete set of genetic material is passed onto the next generation. When bacteria encounter DNA damage, a cell cycle checkpoint is activated by expressing a cell division inhibitor. The prevailing model is that activation of the DNA damage response and protease-mediated degradation of the inhibitor is sufficient to regulate the checkpoint process. Our recent genome-wide screens identified the gene ddcA as critical for surviving exposure to DNA damage. Similar to the checkpoint recovery proteases, the DNA damage sensitivity resulting from ddcA deletion depends on the checkpoint enforcement protein YneA. Using several genetic approaches, we show that DdcA function is distinct from the checkpoint recovery process. Deletion of ddcA resulted in sensitivity to yneA overexpression independent of YneA protein levels and stability, further supporting the conclusion that DdcA regulates YneA independent of proteolysis. Using a functional GFP-YneA fusion we found that DdcA prevents YneA-dependent cell elongation independent of YneA localization. Together, our results suggest that DdcA acts by helping to set a threshold of YneA required to establish the cell cycle checkpoint, uncovering a new regulatory step controlling activation of the DNA damage checkpoint in Bacillus subtilis.
Collapse
Affiliation(s)
- Peter E. Burby
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Zackary W. Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Lyle A. Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, United States
| |
Collapse
|
18
|
Specific regions of the SulA protein recognized and degraded by the ATP-dependent ClpYQ (HslUV) protease in Escherichia coli. Microbiol Res 2018; 220:21-31. [PMID: 30744816 DOI: 10.1016/j.micres.2018.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 11/27/2018] [Accepted: 12/09/2018] [Indexed: 10/27/2022]
Abstract
In Escherichia coli, ClpYQ (HslUV) is a two-component ATP-dependent protease, in which ClpQ is the peptidase subunit and ClpY is the ATPase and unfoldase. ClpY functions to recognize protein substrates, and denature and translocate the unfolded polypeptides into the proteolytic site of ClpQ for degradation. However, it is not clear how the natural substrates are recognized by the ClpYQ protease and the mechanism by which the substrates are selected, unfolded and translocated by ClpY into the interior site of ClpQ hexamers. Both Lon and ClpYQ proteases can degrade SulA, a cell division inhibitor, in bacterial cells. In this study, using yeast two-hybrid and in vivo degradation analyses, we first demonstrated that the C-terminal internal hydrophobic region (139th∼149th aa) of SulA is necessary for binding and degradation by ClpYQ. A conserved region, GFIMRP, between 142th and 147th residues of SulA, were identified among various Gram-negative bacteria. By using MBP-SulA(F143Y) (phenylalanine substituted with tyrosine) as a substrate, our results showed that this conserved residue of SulA is necessary for recognition and degradation by ClpYQ. Supporting these data, MBP-SulA(F143Y), MBP-SulA(F143N) (phenylalanine substituted with asparagine) led to a longer half-life with ClpYQ protease in vivo. In contrast, MBP-SulA(F143D) and MBP-SulA(F143S) both have shorter half-lives. Therefore, in the E. coli ClpYQ protease complex, ClpY recognizes the C-terminal region of SulA, and F143 of SulA plays an important role for the recognition and degradation by ClpYQ protease.
Collapse
|
19
|
Warr AR, Klimova AN, Nwaobasi AN, Sandler SJ. Protease-deficient SOS constitutive cells have RecN-dependent cell division phenotypes. Mol Microbiol 2018; 111:405-422. [PMID: 30422330 DOI: 10.1111/mmi.14162] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2018] [Indexed: 02/05/2023]
Abstract
In Escherichia coli, after DNA damage, the SOS response increases the transcription (and protein levels) of approximately 50 genes. As DNA repair ensues, the level of transcription returns to homeostatic levels. ClpXP and other proteases return the high levels of several SOS proteins to homeostasis. When all SOS genes are constitutively expressed and many SOS proteins are stabilized by the removal of ClpXP, microscopic analysis shows that cells filament, produce mini-cells and have branching protrusions along their length. The only SOS gene required (of 19 tested) for the cell length phenotype is recN. RecN is a member of the Structural Maintenance of Chromosome (SMC) class of proteins. It can hold pieces of DNA together and is important for double-strand break repair (DSBR). RecN is degraded by ClpXP. Overexpression of recN+ in the absence of ClpXP or recN4174 (A552S, A553V), a mutant not recognized by ClpXP, produce filamentous cells with nucleoid partitioning defects. It is hypothesized that when produced at high levels during the SOS response, RecN interferes with nucleoid partitioning and Z-Ring function by holding together sections of the nucleoid, or sister nucleoids, providing another way to inhibit cell division.
Collapse
Affiliation(s)
- Alyson R Warr
- Department of Microbiology, Morrill Science Center IV N203, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Anastasiia N Klimova
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Amy N Nwaobasi
- Department of Microbiology, Morrill Science Center IV N203, University of Massachusetts Amherst, Amherst, MA, 01003, USA.,University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06032, USA
| | - Steven J Sandler
- Department of Microbiology, Morrill Science Center IV N203, University of Massachusetts Amherst, Amherst, MA, 01003, USA.,Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| |
Collapse
|
20
|
Burby PE, Simmons ZW, Schroeder JW, Simmons LA. Discovery of a dual protease mechanism that promotes DNA damage checkpoint recovery. PLoS Genet 2018; 14:e1007512. [PMID: 29979679 PMCID: PMC6051672 DOI: 10.1371/journal.pgen.1007512] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 07/18/2018] [Accepted: 06/23/2018] [Indexed: 02/07/2023] Open
Abstract
The DNA damage response is a signaling pathway found throughout biology. In many bacteria the DNA damage checkpoint is enforced by inducing expression of a small, membrane bound inhibitor that delays cell division providing time to repair damaged chromosomes. How cells promote checkpoint recovery after sensing successful repair is unknown. By using a high-throughput, forward genetic screen, we identified two unrelated proteases, YlbL and CtpA, that promote DNA damage checkpoint recovery in Bacillus subtilis. Deletion of both proteases leads to accumulation of the checkpoint protein YneA. We show that DNA damage sensitivity and increased cell elongation in protease mutants depends on yneA. Further, expression of YneA in protease mutants was sufficient to inhibit cell proliferation. Finally, we show that both proteases interact with YneA and that one of the two proteases, CtpA, directly cleaves YneA in vitro. With these results, we report the mechanism for DNA damage checkpoint recovery in bacteria that use membrane bound cell division inhibitors.
Collapse
Affiliation(s)
- Peter E. Burby
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Zackary W. Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Jeremy W. Schroeder
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Lyle A. Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| |
Collapse
|
21
|
Puri N, Karzai AW. HspQ Functions as a Unique Specificity-Enhancing Factor for the AAA+ Lon Protease. Mol Cell 2017; 66:672-683.e4. [PMID: 28575662 DOI: 10.1016/j.molcel.2017.05.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/24/2017] [Accepted: 05/16/2017] [Indexed: 11/26/2022]
Abstract
The AAA+ Lon protease is conserved from bacteria to humans, performs crucial roles in protein homeostasis, and is implicated in bacterial pathogenesis and human disease. We investigated how Lon selectively degrades specific substrates among a diverse array of potential targets. We report the discovery of HspQ as a new Lon substrate, unique specificity-enhancing factor, and potent allosteric activator. Lon recognizes HspQ via a C-terminal degron, whose precise presentation, in synergy with multipartite contacts with the native core of HspQ, is required for allosteric Lon activation. Productive HspQ-Lon engagement enhances degradation of multiple new and known Lon substrates. Our studies reveal the existence and simultaneous utilization of two distinct substrate recognition sites on Lon, an HspQ binding site and an HspQ-modulated allosteric site. Our investigations unveil an unprecedented regulatory use of an evolutionarily conserved heat shock protein and present a distinctive mechanism for how Lon protease achieves temporally enhanced substrate selectivity.
Collapse
Affiliation(s)
- Neha Puri
- Department of Biochemistry and Cell Biology, Center for Infectious Diseases, Graduate Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - A Wali Karzai
- Department of Biochemistry and Cell Biology, Center for Infectious Diseases, Graduate Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY 11794, USA.
| |
Collapse
|
22
|
Bittner LM, Arends J, Narberhaus F. Mini review: ATP-dependent proteases in bacteria. Biopolymers 2017; 105:505-17. [PMID: 26971705 DOI: 10.1002/bip.22831] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 02/11/2016] [Accepted: 03/07/2016] [Indexed: 01/22/2023]
Abstract
AAA(+) proteases are universal barrel-like and ATP-fueled machines preventing the accumulation of aberrant proteins and regulating the proteome according to the cellular demand. They are characterized by two separate operating units, the ATPase and peptidase domains. ATP-dependent unfolding and translocation of a substrate into the proteolytic chamber is followed by ATP-independent degradation. This review addresses the structure and function of bacterial AAA(+) proteases with a focus on the ATP-driven mechanisms and the coordinated movements in the complex mainly based on the knowledge of ClpXP. We conclude by discussing strategies how novel protease substrates can be trapped by mutated AAA(+) protease variants. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 505-517, 2016.
Collapse
Affiliation(s)
| | - Jan Arends
- Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | | |
Collapse
|
23
|
Malik IT, Brötz-Oesterhelt H. Conformational control of the bacterial Clp protease by natural product antibiotics. Nat Prod Rep 2017; 34:815-831. [DOI: 10.1039/c6np00125d] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Natural products targeting the bacterial Clp protease unravel key interfaces for protein–protein–interaction and long-distance conformational control.
Collapse
Affiliation(s)
- I. T. Malik
- Department of Microbial Bioactive Compounds
- Interfaculty Institute of Microbiology and Infection Medicine
- University of Tuebingen
- Germany
| | - H. Brötz-Oesterhelt
- Department of Microbial Bioactive Compounds
- Interfaculty Institute of Microbiology and Infection Medicine
- University of Tuebingen
- Germany
| |
Collapse
|
24
|
Tsai CH, Ho YH, Sung TC, Wu WF, Chen CS. Escherichia coli Proteome Microarrays Identified the Substrates of ClpYQ Protease. Mol Cell Proteomics 2016; 16:113-120. [PMID: 27864322 DOI: 10.1074/mcp.m116.065482] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Indexed: 01/12/2023] Open
Abstract
Proteolysis is a vital mechanism to regulate the cellular proteome in all kingdoms of life, and ATP-dependent proteases play a crucial role within this process. In Escherichia coli, ClpYQ is one of the primary ATP-dependent proteases. In addition to function with removals of abnormal peptides in the cells, ClpYQ degrades regulatory proteins if necessary and thus let cells adjust to various environmental conditions. In E. coli, SulA, RcsA, RpoH and TraJ as well as RNase R, have been identified as natural protein substrates of ClpYQ. ClpYQ contains ClpY and ClpQ. The ATPase ClpY is responsible for protein recognition, unfolding, and translocation into the catalytic core of ClpQ. In this study, we use an indirect identification strategy to screen possible ClpY targets with E. coli K12 proteome chips. The chip assay results showed that YbaB strongly bound to ClpY. We used yeast two-hybrid assay to confirm the interactions between ClpY and YbaB protein and determined the Kd between ClpY and YbaB by quartz crystal microbalance. Furthermore, we validated that YbaB was successfully degraded by ClpYQ protease activity using ClpYQ in vitro and in vivo degradation assay. These findings demonstrated the YbaB is a novel substrate of ClpYQ protease. This work also successfully demonstrated that with the use of recognition element of a protease can successfully screen its substrates by indirect proteome chip screening assay.
Collapse
Affiliation(s)
- Chih-Hsuan Tsai
- From the ‡Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Yu-Hsuan Ho
- §Graduate Institute of Systems Biology and Bioinformatics, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan.,¶Department of Biomedical Sciences and Engineering, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan
| | - Tzu-Cheng Sung
- §Graduate Institute of Systems Biology and Bioinformatics, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan.,¶Department of Biomedical Sciences and Engineering, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan
| | - Whei-Fen Wu
- From the ‡Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan;
| | - Chien-Sheng Chen
- §Graduate Institute of Systems Biology and Bioinformatics, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan; .,¶Department of Biomedical Sciences and Engineering, National Central University, No. 300, Jhongda Rd., Jhongli 32001, Taiwan
| |
Collapse
|
25
|
Baytshtok V, Fei X, Grant RA, Baker TA, Sauer RT. A Structurally Dynamic Region of the HslU Intermediate Domain Controls Protein Degradation and ATP Hydrolysis. Structure 2016; 24:1766-1777. [PMID: 27667691 DOI: 10.1016/j.str.2016.08.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/02/2016] [Accepted: 08/06/2016] [Indexed: 11/30/2022]
Abstract
The I domain of HslU sits above the AAA+ ring and forms a funnel-like entry to the axial pore, where protein substrates are engaged, unfolded, and translocated into HslV for degradation. The L199Q I-domain substitution, which was originally reported as a loss-of-function mutation, resides in a segment that appears to adopt multiple conformations as electron density is not observed in HslU and HslUV crystal structures. The L199Q sequence change does not alter the structure of the AAA+ ring or its interactions with HslV but increases I-domain susceptibility to limited endoproteolysis. Notably, the L199Q mutation increases the rate of ATP hydrolysis substantially, results in slower degradation of some proteins but faster degradation of other substrates, and markedly changes the preference of HslUV for initiating degradation at the N or C terminus of model substrates. Thus, a structurally dynamic region of the I domain plays a key role in controlling protein degradation by HslUV.
Collapse
Affiliation(s)
- Vladimir Baytshtok
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Xue Fei
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Robert A Grant
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tania A Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Robert T Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
26
|
Toxin-Antitoxin Modules Are Pliable Switches Activated by Multiple Protease Pathways. Toxins (Basel) 2016; 8:toxins8070214. [PMID: 27409636 PMCID: PMC4963847 DOI: 10.3390/toxins8070214] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 02/06/2023] Open
Abstract
Toxin-antitoxin (TA) modules are bacterial regulatory switches that facilitate conflicting outcomes for cells by promoting a pro-survival phenotypic adaptation and/or by directly mediating cell death, all through the toxin activity upon degradation of antitoxin. Intensive study has revealed specific details of TA module functions, but significant gaps remain about the molecular details of activation via antitoxin degradation used by different bacteria and in different environments. This review summarizes the current state of knowledge about the interaction of antitoxins with cellular proteases Lon and ClpP to mediate TA module activation. An understanding of these processes can answer long-standing questions regarding stochastic versus specific activation of TA modules and provide insight into the potential for manipulation of TA modules to alter bacterial growth.
Collapse
|
27
|
Abstract
Processive proteases, such as ClpXP in E. coli, are conserved enzyme assemblies that can recognize and rapidly degrade proteins. These proteases are used for a number of purposes, including degrading mistranslated proteins and controlling cellular stress response. However, proteolytic machinery within the cell is limited in capacity and can lead to a bottleneck in protein degradation, whereby many proteins compete ('queue') for proteolytic resources. Previous work has demonstrated that such queueing can lead to pronounced statistical relationships between different protein counts when proteins compete for a single common protease. However, real cells contain many different proteases, e.g. ClpXP, ClpAP, and Lon in E. coli, and it is not clear how competition between proteins for multiple classes of protease would influence the dynamics of cellular networks. In the present work, we theoretically demonstrate that a multi-protease proteolytic bottleneck can substantially couple the dynamics for both simple and complex (oscillatory) networks, even between substrates with substantially different affinities for protease. For these networks, queueing often leads to strong positive correlations between protein counts, and these correlations are strongest near the queueing theoretic point of balance. Furthermore, we find that the qualitative behavior of these networks depends on the relative size of the absolute affinity of substrate to protease compared to the cross affinity of substrate to protease, leading in certain regimes to priority queue statistics.
Collapse
Affiliation(s)
- Curtis T Ogle
- Department of Physics, Virginia Tech, 50 West Campus Dr, Blacksburg, VA 24061-0435, USA
| | | |
Collapse
|
28
|
Chang CY, Hu HT, Tsai CH, Wu WF. The degradation of RcsA by ClpYQ(HslUV) protease in Escherichia coli. Microbiol Res 2016; 184:42-50. [PMID: 26856452 DOI: 10.1016/j.micres.2016.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 12/21/2015] [Accepted: 01/09/2016] [Indexed: 01/30/2023]
Abstract
In Escherichia coli, RcsA, a positive activator for transcription of cps (capsular polysaccharide synthesis) genes, is degraded by the Lon protease. In lon mutant, the accumulation of RcsA leads to overexpression of capsular polysaccharide. In a previous study, overproduction of ClpYQ(HslUV) protease represses the expression of cpsB∷lacZ, but there has been no direct observation demonstrating that ClpYQ degrades RcsA. By means of a MBP-RcsA fusion protein, we showed that RcsA activated cpsB∷lacZ expression and could be rapidly degraded by Lon protease in SG22622 (lon(+)). Subsequently, the comparative half-life experiments performed in the bacterial strains SG22623 (lon) and AC3112 (lon clpY clpQ) indicated that the RcsA turnover rate in AC3112 was relatively slow and RcsA was stable at 30°C or 41°C. In addition, ClpY could interact with RscA in an in vitro pull-down assay, and the more rapid degradation of RcsA was observed in the presence of ClpYQ protease at 41°C. Thus, we conclude that RcsA is indeed proteolized by ClpYQ protease.
Collapse
Affiliation(s)
- Chun-Yang Chang
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Hui-Ting Hu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Chih-Hsuan Tsai
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Whei-Fen Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC.
| |
Collapse
|
29
|
Olivares AO, Baker TA, Sauer RT. Mechanistic insights into bacterial AAA+ proteases and protein-remodelling machines. Nat Rev Microbiol 2015; 14:33-44. [PMID: 26639779 DOI: 10.1038/nrmicro.2015.4] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To maintain protein homeostasis, AAA+ proteolytic machines degrade damaged and unneeded proteins in bacteria, archaea and eukaryotes. This process involves the ATP-dependent unfolding of a target protein and its subsequent translocation into a self-compartmentalized proteolytic chamber. Related AAA+ enzymes also disaggregate and remodel proteins. Recent structural and biochemical studies, in combination with direct visualization of unfolding and translocation in single-molecule experiments, have illuminated the molecular mechanisms behind these processes and suggest how remodelling of macromolecular complexes by AAA+ enzymes could occur without global denaturation. In this Review, we discuss the structural and mechanistic features of AAA+ proteases and remodelling machines, focusing on the bacterial ClpXP and ClpX as paradigms. We also consider the potential of these enzymes as antibacterial targets and outline future challenges for the field.
Collapse
Affiliation(s)
- Adrian O Olivares
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Tania A Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Robert T Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
30
|
Inactivation of Cell Division Protein FtsZ by SulA Makes Lon Indispensable for the Viability of a ppGpp0 Strain of Escherichia coli. J Bacteriol 2015; 198:688-700. [PMID: 26644431 DOI: 10.1128/jb.00693-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/27/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The modified nucleotides (p)ppGpp play an important role in bacterial physiology. While the accumulation of the nucleotides is vital for adaptation to various kinds of stress, changes in the basal level modulates growth rate and vice versa. Studying the phenotypes unique to the strain lacking (p)ppGpp (ppGpp(0)) under overtly unstressed growth conditions may be useful to understand functions regulated by basal levels of (p)ppGpp and its physiological significance. In this study, we show that the ppGpp(0) strain, unlike the wild type, requires the Lon protease for cell division and viability in LB. Our results indicate the decrease in FtsZ concentration in the ppGpp(0) strain makes cell division vulnerable to SulA inhibition. We did not find evidence for SOS induction contributing to the cell division defect in the ppGpp(0) Δlon strain. Based on the results, we propose that basal levels of (p)ppGpp are required to sustain normal cell division in Escherichia coli during growth in rich medium and that the basal SulA level set by Lon protease is important for insulating cell division against a decrease in FtsZ concentration and conditions that can increase the susceptibility of FtsZ to SulA. IMPORTANCE The physiology of the stringent response has been the subject of investigation for more than 4 decades, with the majority of the work carried out using the bacterial model organism Escherichia coli. These studies have revealed that the accumulation of (p)ppGpp, the effector of the stringent response, is associated with growth retardation and changes in gene expression that vary with the intracellular concentration of (p)ppGpp. By studying a synthetic lethal phenotype, we have uncovered a function modulated by the basal levels of (p)ppGpp and studied its physiological significance. Our results show that (p)ppGpp and Lon protease contribute to the robustness of the cell division machinery in E. coli during growth in rich medium.
Collapse
|
31
|
Meenakshi S, Munavar MH. Suppression of capsule expression in Δlon strains of Escherichia coli by two novel rpoB mutations in concert with HNS: possible role for DNA bending at rcsA promoter. Microbiologyopen 2015; 4:712-29. [PMID: 26403574 PMCID: PMC4618605 DOI: 10.1002/mbo3.268] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/23/2015] [Accepted: 05/04/2015] [Indexed: 11/29/2022] Open
Abstract
Analyses of mutations in genes coding for subunits of RNA polymerase always throw more light on the intricate events that regulate the expression of gene(s). Lon protease of Escherichia coli is implicated in the turnover of RcsA (positive regulator of genes involved in capsular polysaccharide synthesis) and SulA (cell division inhibitor induced upon DNA damage). Failure to degrade RcsA and SulA makes lon mutant cells to overproduce capsular polysaccharides and to become sensitive to DNA damaging agents. Earlier reports on suppressors for these characteristic lon phenotypes related the role of cochaperon DnaJ and tmRNA. Here, we report the isolation and characterization of two novel mutations in rpoB gene capable of modulating the expression of cps genes in Δlon strains of E. coli in concert with HNS. clpA, clpB, clpY, and clpQ mutations do not affect this capsule expression suppressor (Ces) phenotype. These mutant RNA polymerases affect rcsA transcription, but per se are not defective either at rcsA or at cps promoters. The results combined with bioinformatics analyses indicate that the weaker interaction between the enzyme and DNA::RNA hybrid during transcription might play a vital role in the lower level expression of rcsA. These results might have relevance to pathogenesis in related bacteria.
Collapse
Affiliation(s)
- Shanmugaraja Meenakshi
- Department of Molecular Biology, School of Biological Sciences, Centre for Advanced Studies in Functional and Organismal Genomics, Madurai Kamaraj University [University with Potential for Excellence], Madurai, Tamil Nadu, 625 021, India
| | - M Hussain Munavar
- Department of Molecular Biology, School of Biological Sciences, Centre for Advanced Studies in Functional and Organismal Genomics, Madurai Kamaraj University [University with Potential for Excellence], Madurai, Tamil Nadu, 625 021, India
| |
Collapse
|
32
|
Vishnyakov IE, Borchsenius SN. Mycoplasma heat shock proteins and their genes. Microbiology (Reading) 2014. [DOI: 10.1134/s002626171306012x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
|
33
|
Kim J, Hong H, Heo A, Park W. Indole toxicity involves the inhibition of adenosine triphosphate production and protein folding in Pseudomonas putida. FEMS Microbiol Lett 2013; 343:89-99. [PMID: 23527579 DOI: 10.1111/1574-6968.12135] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 03/08/2013] [Accepted: 03/15/2013] [Indexed: 01/11/2023] Open
Abstract
High concentrations of indole are known to be toxic to cells due to perturbations in membrane potential. Here, we report for the first time a transcriptome analysis of a soil model bacterium, Pseudomonas putida KT2440, under indole treatment. We demonstrated that 47 genes are differentially expressed, including 11 genes involved in the tricarboxylic acid cycle (TCA cycle) and 12 genes involved in chaperone and protease functions (hslV, hslU, htpG, grpE, dnaK, ibpA, groEL, groES, clpB, lon-1, lon-2, and hflk). Mutant analysis supported the observation that protease genes including hslU are essential for the indole resistance of Pseudomonas strains. Subsequent biochemical analyses have shown that indole increases the NADH/NAD(+) ratio and decreases the adenosine triphosphate (ATP) concentration inside cells, due to membrane perturbation and higher expression of TCA cycle genes in the presence of indole. This energy reduction leads to a reduction in cell size and an enhancement of biofilm formation in P. putida. The observed upregulation in many chaperones and proteases led us to speculate that protein folding might be inhibited by indole treatment. Interestingly, our in vitro protein-refolding assay using malate dehydrogenase with purified GroEL/GroES demonstrated that indole interferes with protein folding. Taken together, our data provide new evidence that indole causes toxicity to P. putida by inhibiting cellular energy production and protein folding.
Collapse
Affiliation(s)
- Jisun Kim
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Korea
| | | | | | | |
Collapse
|
34
|
Liang W, Deutscher MP. Transfer-messenger RNA-SmpB protein regulates ribonuclease R turnover by promoting binding of HslUV and Lon proteases. J Biol Chem 2012; 287:33472-9. [PMID: 22879590 DOI: 10.1074/jbc.m112.375287] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RNase R, an important exoribonuclease involved in degradation of structured RNA, is subject to a novel mechanism of regulation. The enzyme is extremely unstable in rapidly growing cells but becomes stabilized under conditions of stress, such as stationary phase or cold shock. RNase R instability results from acetylation which promotes binding of tmRNA-SmpB, two trans-translation factors, to its C-terminal region. Here, we examine how binding of tmRNA-SmpB leads to proteolysis of RNase R. We show that RNase R degradation is due to two proteases, HslUV and Lon. In their absence, RNase R is stable. We also show, using an in vitro system that accurately replicates the in vivo process, that tmRNA-SmpB is not essential, but it stimulates binding of the protease to the N-terminal region of RNase R and that it does so by a direct interaction between the protease and SmpB which stabilizes protease binding. Thus, a sequence of events, initiated by acetylation of a single Lys residue, results in proteolysis of RNase R in exponential phase cells. RNase R in stationary phase or in cold-shocked cells is not acetylated, and thereby remains stable. Such a regulatory mechanism, dependent on protein acetylation, has not been observed previously in bacterial cells.
Collapse
Affiliation(s)
- Wenxing Liang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33101, USA
| | | |
Collapse
|
35
|
Error-prone PCR mutagenesis reveals functional domains of a bacterial transcriptional activator, TraJ. J Bacteriol 2012; 194:3670-7. [PMID: 22563049 DOI: 10.1128/jb.00312-12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
TraJ is the essential activator of P(Y), the promoter of the F and F-like plasmid tra operon that encodes the majority of the proteins for bacterial conjugation. By combining error-prone PCR mutagenesis with a two-plasmid screen, we isolated 55 missense mutations in traJ, each affecting the ability of TraJ to activate P(Y). These mutations define two distinct functional clusters (amino acids [aa] 21 to 117 and aa 150 to 219). Limited proteolytic analysis of TraJ suggested that the N- and C-terminal functional clusters are two structurally distinct domains. Most TraJ mutants exhibited decreased intracellular protein levels, and the HslVU protease-chaperone pair was found to be responsible for degrading those mutants without extracytoplasmic stress-induced overexpression. In vivo cross-linking analysis of TraJ mutants indicated that the N-terminal domain is responsible for dimerization. This was confirmed by the finding that the purified N-terminal region of TraJ forms dimers in solution. The levels of dimerization and in vivo activities of TraJ mutants are well correlated, suggesting that dimerization of TraJ is required for its biological function. We propose that the regulation of TraJ dimerization and/or its susceptibility to HslVU could be a key mechanism in various signaling processes for controlling bacterial conjugation in response to physiological or environmental stimuli.
Collapse
|
36
|
Gur E, Biran D, Ron EZ. Regulated proteolysis in Gram-negative bacteria--how and when? Nat Rev Microbiol 2011; 9:839-48. [PMID: 22020261 DOI: 10.1038/nrmicro2669] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Most bacteria live in a dynamic environment where temperature, availability of nutrients and the presence of various chemicals vary, which requires rapid adaptation. Many of the adaptive changes are determined by changes in the transcription of global regulatory networks, but this response is slow because most bacterial proteins are stable and their concentration remains high even after transcription slows down. To respond rapidly, an additional level of regulation has evolved: the degradation of key proteins. However, as proteolysis is an irreversible process, it is subject to tight regulation of substrate binding and degradation. Here we review the roles of the proteolytic enzymes in Gram-negative bacteria and how these enzymes can be regulated to target only a subset of proteins.
Collapse
Affiliation(s)
- Eyal Gur
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | | | | |
Collapse
|
37
|
Kubik S, Wegrzyn K, Pierechod M, Konieczny I. Opposing effects of DNA on proteolysis of a replication initiator. Nucleic Acids Res 2011; 40:1148-59. [PMID: 21976729 PMCID: PMC3273809 DOI: 10.1093/nar/gkr813] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
DNA replication initiation proteins (Reps) are subjected to degradation by cellular proteases. We investigated how the formation of nucleoprotein complex, involving Rep and a protease, affects Rep degradation. All known Escherichia coli AAA+ cytosolic proteases and the replication initiation protein TrfA of the broad-host-range plasmid RK2 were used. Our results revealed that DNA influences the degradation process and that the observed effects are opposite and protease specific. In the case of ClpXP and ClpYQ proteases, DNA abolishes proteolysis, while in the case of ClpAP and Lon proteases it stimulates the process. ClpX and ClpY cannot interact with DNA-bound TrfA, while the ClpAP and Lon activities are enhanced by the formation of nucleoprotein complexes involving both the protease and TrfA. Lon has to interact with TrfA before contacting DNA, or this interaction can occur with TrfA already bound to DNA. The TrfA degradation by Lon can be carried out only on DNA. The absence of Lon results with higher stability of TrfA in the cell.
Collapse
Affiliation(s)
- Slawomir Kubik
- Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk, Gdansk, Poland
| | | | | | | |
Collapse
|
38
|
Stepwise activity of ClpY (HslU) mutants in the processive degradation of Escherichia coli ClpYQ (HslUV) protease substrates. J Bacteriol 2011; 193:5465-76. [PMID: 21803990 DOI: 10.1128/jb.05128-11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Escherichia coli, ClpYQ (HslUV) is a two-component ATP-dependent protease composed of ClpY (HslU), an ATPase with unfolding activity, and ClpQ (HslV), a peptidase. In the ClpYQ proteolytic complex, the hexameric rings of ClpY (HslU) are responsible for protein recognition, unfolding, and translocation into the proteolytic inner chamber of the dodecameric ClpQ (HslV). Each of the three domains, N, I, and C, in ClpY has its own distinct activity. The double loops (amino acids [aa] 137 to 150 and 175 to 209) in domain I of ClpY are necessary for initial recognition/tethering of natural substrates such as SulA, a cell division inhibitor protein. The highly conserved sequence GYVG (aa 90 to 93) pore I site, along with the GESSG pore II site (aa 265 to 269), contribute to the central pore of ClpY in domain N. These two central loops of ClpY are in the center of its hexameric ring in which the energy of ATP hydrolysis allows substrate translocation and then degradation by ClpQ. However, no data have been obtained to determine the effect of the central loops on substrate binding or as part of the processivity of the ClpYQ complex. Thus, we probed the features of ClpY important for substrate engagement and protease processivity via random PCR or site-specific mutagenesis. In yeast two-hybrid analysis and pulldown assays, using isolated ClpY mutants and the pore I or pore II site of ClpY, each was examined for its influence on the adjoining structural regions of the substrates. The pore I site is essential for the translocation of the engaged substrates. Our in vivo study of the ClpY mutants also revealed that an ATP-binding site in domain N, separate from its role in polypeptide (ClpY) oligomerization, is required for complex formation with ClpQ. Additionally, we found that the tyrosine residue at position 408 in ClpY is critical for stabilization of hexamer formation between subunits. Therefore, our studies suggest that stepwise activities of the ClpYQ protease are necessary to facilitate the processive degradation of its natural substrates.
Collapse
|
39
|
Mitochondrial localization of the threonine peptidase PfHslV, a ClpQ ortholog in Plasmodium falciparum. Int J Parasitol 2010; 40:1517-23. [DOI: 10.1016/j.ijpara.2010.05.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/18/2010] [Accepted: 05/04/2010] [Indexed: 12/17/2022]
|
40
|
Co-expression of Skp and FkpA chaperones improves cell viability and alters the global expression of stress response genes during scFvD1.3 production. Microb Cell Fact 2010; 9:22. [PMID: 20388215 PMCID: PMC2868799 DOI: 10.1186/1475-2859-9-22] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 04/13/2010] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND The overexpression of scFv antibody fragments in the periplasmic space of Escherichia coli frequently results in extensive protein misfolding and loss of cell viability. Although protein folding factors such as Skp and FkpA are often exploited to restore the solubility and functionality of recombinant protein products, their exact impact on cellular metabolism during periplasmic antibody fragment expression is not clearly understood. In this study, we expressed the scFvD1.3 antibody fragment in E. coli BL21 and evaluated the overall physiological and global gene expression changes upon Skp or FkpA co-expression. RESULTS The periplasmic expression of scFvD1.3 led to a rapid accumulation of insoluble scFvD1.3 proteins and a decrease in cell viability. The co-expression of Skp and FkpA improved scFvD1.3 solubility and cell viability in a dosage-dependent manner. Through mutagenesis experiments, it was found that only the chaperone activity of FkpA, not the peptidyl-prolyl isomerase (PPIase) activity, is required for the improvement in cell viability. Global gene expression analysis of the scFvD1.3 cells over the chaperone-expressing cells showed a clear up-regulation of genes involved in heat-shock and misfolded protein stress responses. These included genes of the major HSP70 DnaK chaperone family and key proteases belonging to the Clp and Lon protease systems. Other metabolic gene expression trends include: (1) the differential regulation of several energy metabolic genes, (2) down-regulation of the central metabolic TCA cycle and transport genes, and (3) up-regulation of ribosomal genes. CONCLUSIONS The simultaneous activation of multiple stress related and other metabolic genes may constitute the stress response to protein misfolding in the scFvD1.3 cells. These gene expression information could prove to be valuable for the selection and construction of reporter contructs to monitor the misfolded protein stress response during antibody fragment production.
Collapse
|
41
|
Van Melderen L, Aertsen A. Regulation and quality control by Lon-dependent proteolysis. Res Microbiol 2009; 160:645-51. [PMID: 19772918 DOI: 10.1016/j.resmic.2009.08.021] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 08/19/2009] [Accepted: 08/20/2009] [Indexed: 11/17/2022]
Abstract
After their first discovery in Escherichia coli, Lon homologues were found to be widely distributed among prokaryotes to eukaryotes. The ATP-dependent Lon protease belongs to the AAA(+) (ATPases associated with a variety of cellular activities) superfamily, and is involved in both general quality control by degrading abnormal proteins and in the specific control of several regulatory proteins. As such, this enzyme has a pivotal role in quality control and cellular physiology. This review focuses on mechanisms of degradation both from the protease and substrate points of view, and discusses the role of Lon in global regulation, stress response and virulence.
Collapse
Affiliation(s)
- Laurence Van Melderen
- Génétique et Physiologie Bactérienne, Université Libre de Bruxelles, Faculté des Sciences, IBMM-DBM, 12 Rue des Professeurs Jeneer et Brachet, B-6041 Gosselies, Belgium.
| | | |
Collapse
|
42
|
Pruteanu M, Baker TA. Proteolysis in the SOS response and metal homeostasis in Escherichia coli. Res Microbiol 2009; 160:677-83. [PMID: 19747971 DOI: 10.1016/j.resmic.2009.08.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 08/15/2009] [Accepted: 08/17/2009] [Indexed: 10/20/2022]
Abstract
Proteolysis is used by all forms of life for shaping the proteome in response to adverse environmental conditions in order to ensure optimal survival. Here we will address the role of proteolysis in helping cells respond to environmental stress, with a focus on the impact of proteolysis under DNA-damaging conditions and in maintenance of cellular homeostasis in response to metal exposure in bacteria.
Collapse
Affiliation(s)
- Mihaela Pruteanu
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Building 68-523, 77 Massachusetts Ave, Cambridge, MA 02139, USA.
| | | |
Collapse
|
43
|
Characterization of the Escherichia coli ClpY (HslU) substrate recognition site in the ClpYQ (HslUV) protease using the yeast two-hybrid system. J Bacteriol 2009; 191:4218-31. [PMID: 19395483 DOI: 10.1128/jb.00089-09] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Escherichia coli, ClpYQ (HslUV) is a two-component ATP-dependent protease in which ClpQ is the peptidase subunit and ClpY is the ATPase and the substrate-binding subunit. The ATP-dependent proteolysis is mediated by substrate recognition in the ClpYQ complex. ClpY has three domains, N, I, and C, and these domains are discrete and exhibit different binding preferences. In vivo, ClpYQ targets SulA, RcsA, RpoH, and TraJ molecules. In this study, ClpY was analyzed to identify the molecular determinants required for the binding of its natural protein substrates. Using yeast two-hybrid analysis, we showed that domain I of ClpY contains the residues responsible for recognition of its natural substrates, while domain C is necessary to engage ClpQ. Moreover, the specific residues that lie in the amino acid (aa) 137 to 150 (loop 1) and aa 175 to 209 (loop 2) double loops in domain I of ClpY were shown to be necessary for natural substrate interaction. Additionally, the two-hybrid system, together with random PCR mutagenesis, allowed the isolation of ClpY mutants that displayed a range of binding activities with SulA, including a mutant with no SulA binding trait. Subsequently, via methyl methanesulfonate tests and cpsB::lacZ assays with, e.g., SulA and RcsA as targets, we concluded that aa 175 to 209 of loop 2 are involved in the tethering of natural substrates, and it is likely that both loops, aa 137 to 150 and aa 175 to 209, of ClpY domain I may assist in the delivery of substrates into the inner core for ultimate degradation by ClpQ.
Collapse
|
44
|
Koodathingal P, Jaffe NE, Kraut DA, Prakash S, Fishbain S, Herman C, Matouschek A. ATP-dependent proteases differ substantially in their ability to unfold globular proteins. J Biol Chem 2009; 284:18674-84. [PMID: 19383601 DOI: 10.1074/jbc.m900783200] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATP-dependent proteases control the concentrations of hundreds of regulatory proteins and remove damaged or misfolded proteins from cells. They select their substrates primarily by recognizing sequence motifs or covalent modifications. Once a substrate is bound to the protease, it has to be unfolded and translocated into the proteolytic chamber to be degraded. Some proteases appear to be promiscuous, degrading substrates with poorly defined targeting signals, which suggests that selectivity may be controlled at additional levels. Here we compare the abilities of representatives from all classes of ATP-dependent proteases to unfold a model substrate protein and find that the unfolding abilities range over more than 2 orders of magnitude. We propose that these differences in unfolding abilities contribute to the fates of substrate proteins and may act as a further layer of selectivity during protein destruction.
Collapse
Affiliation(s)
- Prakash Koodathingal
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60208, USA
| | | | | | | | | | | | | |
Collapse
|
45
|
Lien HY, Yu CH, Liou CM, Wu WF. Regulation of clpQ⁺Y⁺ (hslV⁺U⁺) gene expression in Escherichia coli. Open Microbiol J 2009; 3:29-39. [PMID: 19440251 PMCID: PMC2681174 DOI: 10.2174/1874285800903010029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 02/17/2009] [Accepted: 02/24/2009] [Indexed: 11/24/2022] Open
Abstract
The Escherichia coli ClpYQ (HslUV) complex is an ATP-dependent protease, and the clpQ+Y+ (hslV+U+) operon encodes two heat shock proteins, ClpQ and ClpY, respectively. The transcriptional (op) or translational (pr) clpQ+::lacZ fusion gene was constructed, with the clpQ+Y+ promoter fused to a lacZ reporter gene. The clpQ+::lacZ (op or pr) fusion gene was each crossed into lambda phage. The λclpQ+::lacZ+ (op), a transcriptional fusion gene, was used to form lysogens in the wild-type, rpoH or/and rpoS mutants. Upon shifting the temperature up from 30 °C to 42 °C, the wild-type λclpQ+::lacZ+ (op) demonstrates an increased β-galactosidase (βGal) activity. However, the βGal activity of clpQ+::lacZ+ (op) was decreased in the rpoH and rpoH rpoS mutants but not in the rpoS mutant. The levels of clpQ+::lacZ+ mRNA transcripts correlated well to their βGal activity. Similarly, the expression of the clpQ+::lacZ+ gene fusion was nearly identical to the clpQ+Y+ transcript under the in vivo condition. The clpQm1::lacZ+, containing a point mutation in the -10 promoter region for RpoH binding, showed decreased βGal activity, independent of activation by RpoH. We conclude that RpoH itself regulates clpQ+Y+ gene expression. In addition, the clpQ+Y+ message carries a conserved 71 bp at the 5’ untranslated region (5’UTR) that is predicted to form the stem-loop structure by analysis of its RNA secondary structure. The clpQm2Δ40::lacZ+, with a 40 bp deletion in the 5’UTR, showed a decreased βGal activity. In addition, from our results, it is suggested that this stem-loop structure is necessary for the stability of the clpQ+Y+ message.
Collapse
Affiliation(s)
- Hsiang-Yun Lien
- Department of Agricultural Chemistry, National Taiwan University, Taipei (106), Taiwan, R.O.C
| | | | | | | |
Collapse
|
46
|
Pruteanu M, Baker TA. Controlled degradation by ClpXP protease tunes the levels of the excision repair protein UvrA to the extent of DNA damage. Mol Microbiol 2008; 71:912-24. [PMID: 19183285 DOI: 10.1111/j.1365-2958.2008.06574.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
UV irradiation damages DNA and activates expression of genes encoding proteins helpful for survival under DNA stress. These proteins are often deleterious in the absence of DNA damage. Here, we investigate mechanisms used to regulate the levels of DNA-repair proteins during recovery by studying control of the nucleotide excision repair (NER) protein UvrA. We show that UvrA is induced after UV irradiation and reaches maximum levels between approximately 20 and 120 min post UV. During post-UV recovery, UvrA levels decrease principally as a result of ClpXP-dependent protein degradation. The rate of UvrA degradation depends on the amount of unrepaired pyrimidine dimers present; this degradation rate is initially slow shortly after UV, but increases as damage is repaired. This increase in UvrA degradation as repair progresses is also influenced by protein-protein interactions. Genetic and in vitro experiments support the conclusion that UvrA-UvrB interactions antagonize degradation. In contrast, Mfd appears to act as an enhancer of UvrA turnover. Thus, our results reveal that a complex network of interactions contribute to tuning the level of UvrA in the cell in response to the extent of DNA damage and nicely mirror findings with excision repair proteins from eukaryotes, which are controlled by proteolysis in a similar manner.
Collapse
Affiliation(s)
- Mihaela Pruteanu
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | |
Collapse
|
47
|
Abstract
A wide variety of peptidases associate with vital biological pathways, but the origin and evolution of their tremendous diversity are poorly defined. Application of the MEROPS classification to a comprehensive set of genomes yields a simple pattern of peptidase distribution and provides insight into the organization of proteolysis in all forms of life. Unexpectedly, a near ubiquitous core set of peptidases is shown to contain more types than those unique to higher multicellular organisms. From this core group, an array of eukaryote-specific peptidases evolved to yield well known intracellular and extracellular processes. The paucity of peptidase families unique to higher metazoa suggests gains in proteolytic network complexity required a limited number of biochemical inventions. These findings provide a framework for deeper investigation into the evolutionary forces that shaped each peptidase family and a roadmap to develop a timeline for their expansion as an interconnected system.
Collapse
Affiliation(s)
- Michael J Page
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | | |
Collapse
|
48
|
Lau-Wong IC, Locke T, Ellison MJ, Raivio TL, Frost LS. Activation of the Cpx regulon destabilizes the F plasmid transfer activator, TraJ, via the HslVU protease in Escherichia coli. Mol Microbiol 2007; 67:516-27. [PMID: 18069965 DOI: 10.1111/j.1365-2958.2007.06055.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Escherichia coli CpxAR two-component signal transduction system senses and responds to extracytoplasmic stress. The cpxA101* allele was previously found to reduce F plasmid conjugation by post-transcriptional inactivation of the positive activator TraJ. Microarray analysis revealed upregulation of the protease-chaperone pair, HslVU, which was shown to degrade TraJ in an E. coli C600 cpxA101* background. Double mutants of cpxA101* and hslV or hslU restored TraJ and F conjugation to wild-type levels. The constitutive overexpression of nlpE, an outer membrane lipoprotein that induces the Cpx stress response, also led to HslVU-mediated degradation of TraJ and repression of F transfer. However, Cpx-mediated TraJ degradation appears to be growth phase-dependent, as induction of nlpE in mid-log phase cells did not appreciably alter TraJ levels. Further, His6-TraJ was sensitive to HslVU degradation in vitro only when it was purified from cells overexpressing nlpE. Thus, TraJ appears to become resistant to HslVU during normal growth, with this resistance mapping to the F transfer region. Extracytoplasmic stress prevents this modification of TraJ, leaving it susceptible to HslVU. Thus, the CpxAR stress response indirectly controls the synthesis of the F mating apparatus, a complex transenvelope type IV secretion system, by degrading TraJ.
Collapse
Affiliation(s)
- Isabella C Lau-Wong
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2E9
| | | | | | | | | |
Collapse
|
49
|
Contribution of conserved ATP-dependent proteases of Campylobacter jejuni to stress tolerance and virulence. Appl Environ Microbiol 2007; 73:7803-13. [PMID: 17933920 DOI: 10.1128/aem.00698-07] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In prokaryotic cells the ATP-dependent proteases Lon and ClpP (Clp proteolytic subunit) are involved in the turnover of misfolded proteins and the degradation of regulatory proteins, and depending on the organism, these proteases contribute variably to stress tolerance. We constructed mutants in the lon and clpP genes of the food-borne human pathogen Campylobacter jejuni and found that the growth of both mutants was impaired at high temperature, a condition known to increase the level of misfolded protein. Moreover, the amounts of misfolded protein aggregates were increased when both proteases were absent, and we propose that both ClpP and Lon are involved in eliminating misfolded proteins in C. jejuni. In order to bind misfolded protein, ClpP has to associate with one of several Clp ATPases. Following inactivation of the ATPase genes clpA and clpX, only the clpX mutant displayed the same heat sensitivity as the clpP mutant, indicating that the ClpXP proteolytic complex is responsible for the degradation of heat-damaged proteins in C. jejuni. Notably, ClpP and ClpX are required for growth at 42 degrees C, which is the temperature of the intestinal tract of poultry, one of the primary carriers of C. jejuni. Thus, ClpP and ClpX may be suitable targets of new intervention strategies aimed at reducing C. jejuni in poultry production. Further characterization of the clpP and lon mutants revealed other altered phenotypes, such as reduced motility, less autoagglutination, and lower levels of invasion of INT407 epithelial cells, suggesting that the proteases may contribute to the virulence of C. jejuni.
Collapse
|
50
|
Staats CC, Boldo J, Broetto L, Vainstein M, Schrank A. Comparative genome analysis of proteases, oligopeptide uptake and secretion systems in Mycoplasma spp. Genet Mol Biol 2007. [DOI: 10.1590/s1415-47572007000200009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2023] Open
|