1
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Zhan J, Zeher A, Huang R, Tang WK, Jenkins LM, Xia D. Conformations of Bcs1L undergoing ATP hydrolysis suggest a concerted translocation mechanism for folded iron-sulfur protein substrate. Nat Commun 2024; 15:4655. [PMID: 38821922 PMCID: PMC11143374 DOI: 10.1038/s41467-024-49029-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 05/20/2024] [Indexed: 06/02/2024] Open
Abstract
The human AAA-ATPase Bcs1L translocates the fully assembled Rieske iron-sulfur protein (ISP) precursor across the mitochondrial inner membrane, enabling respiratory Complex III assembly. Exactly how the folded substrate is bound to and released from Bcs1L has been unclear, and there has been ongoing debate as to whether subunits of Bcs1L act in sequence or in unison hydrolyzing ATP when moving the protein cargo. Here, we captured Bcs1L conformations by cryo-EM during active ATP hydrolysis in the presence or absence of ISP substrate. In contrast to the threading mechanism widely employed by AAA proteins in substrate translocation, subunits of Bcs1L alternate uniformly between ATP and ADP conformations without detectable intermediates that have different, co-existing nucleotide states, indicating that the subunits act in concert. We further show that the ISP can be trapped by Bcs1 when its subunits are all in the ADP-bound state, which we propose to be released in the apo form.
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Affiliation(s)
- Jingyu Zhan
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Allison Zeher
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- NIH Intramural Cryo-EM Consortium (NICE), Bethesda, MD, USA
| | - Rick Huang
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- NIH Intramural Cryo-EM Consortium (NICE), Bethesda, MD, USA
| | - Wai Kwan Tang
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Lisa M Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Di Xia
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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2
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Beardslee PC, Schmitz KR. Toxin-based screening of C-terminal tags in Escherichia coli reveals the exceptional potency of ssrA-like degrons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.29.576913. [PMID: 38352471 PMCID: PMC10862746 DOI: 10.1101/2024.01.29.576913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
All bacteria possess ATP-dependent proteases that destroy cytosolic proteins. These enzymes help cells mitigate proteotoxic stress, adapt to changing nutrient availability, regulate virulence phenotypes, and transition to pathogenic lifestyles. Moreover, ATP-dependent proteases have emerged as promising antibacterial and antivirulence targets in a variety of pathogens. The physiological roles of these proteases are largely defined by the complement of proteins that they degrade. Substrates are typically recognized in a highly selective manner, often via short unstructured sequences termed degrons. While a few degrons have been identified and rigorously characterized, we lack a systematic understanding of how proteases select valid degrons from the vast complexity of protein sequence space. Here, we describe a novel high-throughput screening approach in Escherichia coli that couples proteolysis of a protein toxin to cell survival. We used this method to screen a combinatorial library of C-terminal pentapeptide sequences for functionality as proteolytic degrons in wild type E. coli, and in strains lacking components of the ClpXP and ClpAP proteases. By examining the competitive enrichment of sequences over time, we found that about one percent of pentapeptide tags lead to toxin proteolysis. Interestingly, the most enriched degrons were ClpXP-dependent and highly similar to the ssrA tag, one of the most extensively characterized degrons in bacteria. Among ssrA-like sequences, we observed that specific upstream residues correlate with successful recognition. The lack of diversity among strongly enriched sequences suggests that ssrA-like tags comprise a uniquely potent class of short C-terminal degron in E. coli. Efficient proteolysis of substrates lacking such degrons likely requires adaptors or multivalent interactions. These findings broaden our understanding of the constraints that shape the bacterial proteolytic landscape. Our screening approach may be broadly applicable to probing aspects of proteolytic substrate selection in other bacterial systems.
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Affiliation(s)
- Patrick C. Beardslee
- Department of Chemistry & Biochemistry, University of Delaware, Newark DE, 19716
| | - Karl R. Schmitz
- Department of Chemistry & Biochemistry, University of Delaware, Newark DE, 19716
- Department of Biological Sciences, University of Delaware, Newark DE, 19716
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3
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Kumari S, Dhara A, Kumar M. Leptospira ClpP mutant variants in association with the ClpX, acyldepsipeptide, and the trigger factor displays unprecedented gain-of-function. Int J Biol Macromol 2024; 254:127753. [PMID: 38287595 DOI: 10.1016/j.ijbiomac.2023.127753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 10/05/2023] [Accepted: 10/27/2023] [Indexed: 01/31/2024]
Abstract
The functionally active ClpP (LinClpP) of Leptospira interrogans is composed of two different isoforms (LinClpP1 and LinClpP2). In this study, five mutants of LinClpP (LinClpP1E170D, LinClpP1N172D, LinClpP2IG_del, LinClpP2S40AK41N, LinClpP2Y62A) targeting its critical hotspot residues were generated. The functional activity of pure LinClpP mutant variants or its heterocomplex and its effect when associated with a chaperone (LinClpX)/antibiotic acyldepsipeptide (ADEP1)/trigger factor (LinTF) was examined. The two mutants (LinClpP2S40AK41N and LinClpP2Y62A) displayed gain-of-function (GOF) in peptidase activity. The ADEP1-bound heterocomplex (LinClpP1P2S40AK41N and LinClpP1P2Y62A) measured 1.7 and 1.5-fold higher protease activity than ADEP-bound LinClpP1P2. The dynamic light scattering analysis of ADEP1-bound GOF mutants displayed increased hydrodynamic diameter. In the presence of LinTF, the heterocomplex (LinClpP1P2S40AK41N and LinClpP1P2Y62A) exhibited a 3-fold surge in peptidase activity. The deletion mutant (LinClpP2IG_del) or its heterocomplex (LinClpP1P2IG_del) displayed no activity. Similarly, the pure LinClpP1E170D and LinClpP1N172D could not cleave a model dipeptide. However, its heterocomplex (LinClpP1E170DP2 and LinClpP1N172DP2) showed 0.5-fold lower peptidase activity than the LinClpP1P2. Collectively, two mutants (LinClpP2S40AK41N and LinClpP2Y62A) have GOF and can degrade model dipeptide substrate without the aid of LinClpP1 isoform and thus provide new insights into unprecedented LinClpP activation.
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Affiliation(s)
- Surbhi Kumari
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Anusua Dhara
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Manish Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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4
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Taillefer B, Giraud JF, Cascales E. No fitness cost entailed by type VI secretion system synthesis, assembly, contraction, or disassembly in enteroaggregative Escherichia coli. J Bacteriol 2023; 205:e0035723. [PMID: 37971272 PMCID: PMC10729742 DOI: 10.1128/jb.00357-23] [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: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE Bacteria use weapons to deliver effectors into target cells. One of these weapons, the type VI secretion system (T6SS), assembles a contractile tail acting as a spring to propel a toxin-loaded needle. Due to its size and mechanism of action, the T6SS was intuitively thought to be energetically costly. Here, using a combination of mutants and growth measurements in liquid medium, on plates, and in competition experiments, we show that the T6SS does not entail a growth cost to enteroaggregative Escherichia coli.
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Affiliation(s)
- Boris Taillefer
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (LISM, UMR 7255), Institut de Microbiologie de la Méditerranée (IMM), Aix Marseille Univ, CNRS, Marseille, France
| | - Julien F. Giraud
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (LISM, UMR 7255), Institut de Microbiologie de la Méditerranée (IMM), Aix Marseille Univ, CNRS, Marseille, France
| | - Eric Cascales
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (LISM, UMR 7255), Institut de Microbiologie de la Méditerranée (IMM), Aix Marseille Univ, CNRS, Marseille, France
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5
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Pan Y, Zhan J, Jiang Y, Xia D, Scheuring S. A concerted ATPase cycle of the protein transporter AAA-ATPase Bcs1. Nat Commun 2023; 14:6369. [PMID: 37821516 PMCID: PMC10567702 DOI: 10.1038/s41467-023-41806-5] [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: 03/16/2023] [Accepted: 09/18/2023] [Indexed: 10/13/2023] Open
Abstract
Bcs1, a homo-heptameric transmembrane AAA-ATPase, facilitates folded Rieske iron-sulfur protein translocation across the inner mitochondrial membrane. Structures in different nucleotide states (ATPγS, ADP, apo) provided conformational snapshots, but the kinetics and structural transitions of the ATPase cycle remain elusive. Here, using high-speed atomic force microscopy (HS-AFM) and line scanning (HS-AFM-LS), we characterized single-molecule Bcs1 ATPase cycling. While the ATP conformation had ~5600 ms lifetime, independent of the ATP-concentration, the ADP/apo conformation lifetime was ATP-concentration dependent and reached ~320 ms at saturating ATP-concentration, giving a maximum turnover rate of 0.17 s-1. Importantly, Bcs1 ATPase cycle conformational changes occurred in concert. Furthermore, we propose that the transport mechanism involves opening the IMS gate through energetically costly straightening of the transmembrane helices, potentially driving rapid gate resealing. Overall, our results establish a concerted ATPase cycle mechanism in Bcs1, distinct from other AAA-ATPases that use a hand-over-hand mechanism.
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Affiliation(s)
- Yangang Pan
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA
| | - Jingyu Zhan
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yining Jiang
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA
- Biochemistry & Structural Biology, Cell & Developmental Biology, and Molecular Biology (BCMB) Program, Weill Cornell Graduate School of Biomedical Sciences, New York, USA
| | - Di Xia
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Simon Scheuring
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA.
- Department of Physiology & Biophysics, Weill Cornell Medical College, New York, NY, USA.
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, USA.
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6
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Ogbonna EC, Anderson HR, Beardslee PC, Bheemreddy P, Schmitz KR. Interactome Analysis Identifies MSMEI_3879 as a Substrate of Mycolicibacterium smegmatis ClpC1. Microbiol Spectr 2023; 11:e0454822. [PMID: 37341639 PMCID: PMC10433963 DOI: 10.1128/spectrum.04548-22] [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: 11/08/2022] [Accepted: 05/31/2023] [Indexed: 06/22/2023] Open
Abstract
The prevalence of drug-resistant Mycobacterium tuberculosis infections has prompted extensive efforts to exploit new drug targets in this globally important pathogen. ClpC1, the unfoldase component of the essential ClpC1P1P2 protease, has emerged as one particularly promising antibacterial target. However, efforts to identify and characterize compounds that impinge on ClpC1 activity are constrained by our limited knowledge of Clp protease function and regulation. To expand our understanding of ClpC1 physiology, we employed a coimmunoprecipitation and mass spectrometry workflow to identify proteins that interact with ClpC1 in Mycolicibacterium smegmatis, a surrogate for M. tuberculosis. We identify a diverse panel of interaction partners, many of which coimmunoprecipitate with both the regulatory N-terminal domain and the ATPase core of ClpC1. Notably, our interactome analysis establishes MSMEI_3879, a truncated gene product unique to M. smegmatis, as a novel proteolytic substrate. Degradation of MSMEI_3879 by ClpC1P1P2 in vitro requires exposure of its N-terminal sequence, reinforcing the idea that ClpC1 selectively recognizes disordered motifs on substrates. Fluorescent substrates incorporating MSMEI_3879 may be useful in screening for novel ClpC1-targeting antibiotics to help address the challenge of M. tuberculosis drug resistance. IMPORTANCE Drug-resistant tuberculosis infections are a major challenge to global public health. Much effort has been invested in identifying new drug targets in the causative pathogen, Mycobacterium tuberculosis. One such target is the ClpC1 unfoldase. Compounds have been identified that kill M. tuberculosis by disrupting ClpC1 activity, yet the physiological function of ClpC1 in cells has remained poorly defined. Here, we identify interaction partners of ClpC1 in a model mycobacterium. By building a broader understanding of the role of this prospective drug target, we can more effectively develop compounds that inhibit its essential cellular activities.
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Affiliation(s)
- Emmanuel C. Ogbonna
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Henry R. Anderson
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Patrick C. Beardslee
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Priyanka Bheemreddy
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Karl R. Schmitz
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
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7
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Dimitrova YN, Gutierrez JA, Huard K. It's ok to be outnumbered - sub-stoichiometric modulation of homomeric protein complexes. RSC Med Chem 2023; 14:22-46. [PMID: 36760737 PMCID: PMC9890894 DOI: 10.1039/d2md00212d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022] Open
Abstract
An arsenal of molecular tools with increasingly diversified mechanisms of action is being developed by the scientific community to enable biological interrogation and pharmaceutical modulation of targets and pathways of ever increasing complexity. While most small molecules interact with the target of interest in a 1 : 1 relationship, a noteworthy number of recent examples were reported to bind in a sub-stoichiometric manner to a homomeric protein complex. This approach requires molecular understanding of the physiologically relevant protein assemblies and in-depth characterization of the compound's mechanism of action. The recent literature examples summarized here were selected to illustrate methods used to identify and characterize molecules with such mechanisms. The concept of one small molecule targeting a homomeric protein assembly is not new but the subject deserves renewed inspection in light of emerging technologies and increasingly diverse target biology, to ensure relevant in vitro systems are used and valuable compounds with potentially novel sub-stoichiometric mechanisms of action aren't overlooked.
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Affiliation(s)
| | | | - Kim Huard
- Genentech 1 DNA Way South San Francisco CA 94080 USA
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8
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Hong J, Duc NM, Jeong BC, Cho S, Shetye G, Cao J, Lee H, Jeong C, Lee H, Suh JW. Identification of the inhibitory mechanism of ecumicin and rufomycin 4-7 on the proteolytic activity of Mycobacterium tuberculosis ClpC1/ClpP1/ClpP2 complex. Tuberculosis (Edinb) 2023; 138:102298. [PMID: 36580851 PMCID: PMC9892302 DOI: 10.1016/j.tube.2022.102298] [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: 08/29/2022] [Revised: 12/15/2022] [Accepted: 12/18/2022] [Indexed: 12/25/2022]
Abstract
Ecumicin and rufomycin 4-7 disrupt protein homeostasis in Mycobacterium tuberculosis by inhibiting the proteolytic activity of the ClpC1/ClpP1/ClpP2 complex. Although these compounds target ClpC1, their effects on the ATPase activity of ClpC1 and proteolytic activity of ClpC1/ClpP1/ClpP2 vary. Herein, we explored the ClpC1 molecular dynamics with these compounds through fluorescence correlation spectroscopy. The effect of these compounds on the ATPase activity of ClpC1-cys, the recombinant protein for fluorescence labeling, and proteolytic activity of ClpC1-cys/ClpP1/ClpP2 were identical to those of native ClpC1, whereas the intermolecular dynamics of fluorescence-labelled ClpC1 were different. Treatment with up to 1 nM ecumicin increased the population of slower diffused ClpC1 components compared with ClpC1 without ecumicin. However, this population was considerably reduced when treated with 10 nM ecumicin. Rufomycin 4-7 treatment resulted in a slower diffused component of ClpC1, and the portion of this component increased in a concentration-dependent manner. Ecumicin can generate an abnormal ClpC1 component, which cannot form normal ClpC1/ClpP1/ClpP2, via two different modes. Rufomycin 4-7 only generates slower diffused ClpC1 component that is inadequate to form normal ClpC1/ClpP1/ClpP2. Overall, we demonstrate that ecumicin and rufomycin 4-7 use different action mechanisms to generate abnormal ClpC1 components that cannot couple with ClpP1/ClpP2.
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Affiliation(s)
- Jeongpyo Hong
- Interdisciplinary Program of Biomodulation, Graduate School, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea
| | - Nguyen Minh Duc
- Interdisciplinary Program of Biomodulation, Graduate School, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea
| | - Byeong-Chul Jeong
- Division of Biosciences and Bioinformatics, College of Natural Science, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea
| | - Sanghyun Cho
- Institute for Tuberculosis Research, Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Gauri Shetye
- Institute for Tuberculosis Research, Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Jin Cao
- Institute for Tuberculosis Research, Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Hyun Lee
- Biophysics Core at Resource Center, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Cherlhyun Jeong
- Chemical & Biological Integrative Research Center, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea; KHU-KIST Department of Converging Science and Technology, Kyunghee University, Seoul, 02447, Republic of Korea.
| | - Hanki Lee
- Interdisciplinary Program of Biomodulation, Graduate School, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
| | - Joo-Won Suh
- MJ Bioefficacy Research Center, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
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9
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Szczesna E, Zehr EA, Cummings SW, Szyk A, Mahalingan KK, Li Y, Roll-Mecak A. Combinatorial and antagonistic effects of tubulin glutamylation and glycylation on katanin microtubule severing. Dev Cell 2022; 57:2497-2513.e6. [PMID: 36347241 PMCID: PMC9665884 DOI: 10.1016/j.devcel.2022.10.003] [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: 02/24/2022] [Revised: 08/17/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022]
Abstract
Microtubules have spatiotemporally complex posttranslational modification patterns. How cells interpret this tubulin modification code is largely unknown. We show that C. elegans katanin, a microtubule severing AAA ATPase mutated in microcephaly and critical for cell division, axonal elongation, and cilia biogenesis, responds precisely, differentially, and combinatorially to three chemically distinct tubulin modifications-glycylation, glutamylation, and tyrosination-but is insensitive to acetylation. Glutamylation and glycylation are antagonistic rheostats with glycylation protecting microtubules from severing. Katanin exhibits graded and divergent responses to glutamylation on the α- and β-tubulin tails, and these act combinatorially. The katanin hexamer central pore constrains the polyglutamate chain patterns on β-tails recognized productively. Elements distal to the katanin AAA core sense α-tubulin tyrosination, and detyrosination downregulates severing. The multivalent microtubule recognition that enables katanin to read multiple tubulin modification inputs explains in vivo observations and illustrates how effectors can integrate tubulin code signals to produce diverse functional outcomes.
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Affiliation(s)
- Ewa Szczesna
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Elena A Zehr
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Steven W Cummings
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Agnieszka Szyk
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Kishore K Mahalingan
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Yan Li
- Proteomic Core Facility, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA; Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, Bethesda, MD 20892, USA.
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10
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Pareek G. AAA+ proteases: the first line of defense against mitochondrial damage. PeerJ 2022; 10:e14350. [PMID: 36389399 PMCID: PMC9648348 DOI: 10.7717/peerj.14350] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/16/2022] [Indexed: 11/09/2022] Open
Abstract
Mitochondria play essential cellular roles in Adenosine triphosphate (ATP) synthesis, calcium homeostasis, and metabolism, but these vital processes have potentially deadly side effects. The production of the reactive oxygen species (ROS) and the aggregation of misfolded mitochondrial proteins can lead to severe mitochondrial damage and even cell death. The accumulation of mitochondrial damage is strongly implicated in aging and several incurable diseases, including neurodegenerative disorders and cancer. To oppose this, metazoans utilize a variety of quality control strategies, including the degradation of the damaged mitochondrial proteins by the mitochondrial-resident proteases of the ATPase Associated with the diverse cellular Activities (AAA+) family. This mini-review focuses on the quality control mediated by the mitochondrial-resident proteases of the AAA+ family used to combat the accumulation of damaged mitochondria and on how the failure of this mitochondrial quality control contributes to diseases.
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11
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Zhang Y, Wang Y, Wei W, Wang M, Jia S, Yang M, Ge F. Proteomic analysis of the regulatory networks of ClpX in a model cyanobacterium Synechocystis sp. PCC 6803. FRONTIERS IN PLANT SCIENCE 2022; 13:994056. [PMID: 36247581 PMCID: PMC9560874 DOI: 10.3389/fpls.2022.994056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Protein homeostasis is tightly regulated by protein quality control systems such as chaperones and proteases. In cyanobacteria, the ClpXP proteolytic complex is regarded as a representative proteolytic system and consists of a hexameric ATPase ClpX and a tetradecameric peptidase ClpP. However, the functions and molecular mechanisms of ClpX in cyanobacteria remain unclear. This study aimed to decipher the unique contributions and regulatory networks of ClpX in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis). We showed that the interruption of clpX led to slower growth, decreased high light tolerance, and impaired photosynthetic cyclic electron transfer. A quantitative proteomic strategy was employed to globally identify ClpX-regulated proteins in Synechocystis cells. In total, we identified 172 differentially expressed proteins (DEPs) upon the interruption of clpX. Functional analysis revealed that these DEPs are involved in diverse biological processes, including glycolysis, nitrogen assimilation, photosynthetic electron transport, ATP-binding cassette (ABC) transporters, and two-component signal transduction. The expression of 24 DEPs was confirmed by parallel reaction monitoring (PRM) analysis. In particular, many hypothetical or unknown proteins were found to be regulated by ClpX, providing new candidates for future functional studies on ClpX. Together, our study provides a comprehensive ClpX-regulated protein network, and the results serve as an important resource for understanding protein quality control systems in cyanobacteria.
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Affiliation(s)
- Yumeng Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yaqi Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Wei Wei
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Min Wang
- The Analysis and Testing Center, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Shuzhao Jia
- The Analysis and Testing Center, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Mingkun Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Feng Ge
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
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12
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Gustchina A, Li M, Andrianova AG, Kudzhaev AM, Lountos GT, Sekula B, Cherry S, Tropea JE, Smirnov IV, Wlodawer A, Rotanova TV. Unique Structural Fold of LonBA Protease from Bacillus subtilis, a Member of a Newly Identified Subfamily of Lon Proteases. Int J Mol Sci 2022; 23:11425. [PMID: 36232729 PMCID: PMC9569914 DOI: 10.3390/ijms231911425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/21/2022] [Accepted: 09/22/2022] [Indexed: 11/16/2022] Open
Abstract
ATP-dependent Lon proteases are key participants in the quality control system that supports the homeostasis of the cellular proteome. Based on their unique structural and biochemical properties, Lon proteases have been assigned in the MEROPS database to three subfamilies (A, B, and C). All Lons are single-chain, multidomain proteins containing an ATPase and protease domains, with different additional elements present in each subfamily. LonA and LonC proteases are soluble cytoplasmic enzymes, whereas LonBs are membrane-bound. Based on an analysis of the available sequences of Lon proteases, we identified a number of enzymes currently assigned to the LonB subfamily that, although presumably membrane-bound, include structural features more similar to their counterparts in the LonA subfamily. This observation was confirmed by the crystal structure of the proteolytic domain of the enzyme previously assigned as Bacillus subtilis LonB, combined with the modeled structure of its ATPase domain. Several structural features present in both domains differ from their counterparts in either LonA or LonB subfamilies. We thus postulate that this enzyme is the founding member of a newly identified LonBA subfamily, so far found only in the gene sequences of firmicutes.
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Affiliation(s)
- Alla Gustchina
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Mi Li
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Anna G Andrianova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Arsen M Kudzhaev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - George T Lountos
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Bartosz Sekula
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, 90-573 Lodz, Poland
| | - Scott Cherry
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Joseph E Tropea
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Ivan V Smirnov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Alexander Wlodawer
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Tatyana V Rotanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
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13
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Elucidation of the interaction proteome of mitochondrial chaperone Hsp78 highlights its role in protein aggregation during heat stress. J Biol Chem 2022; 298:102494. [PMID: 36115461 PMCID: PMC9574514 DOI: 10.1016/j.jbc.2022.102494] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 09/01/2022] [Accepted: 09/06/2022] [Indexed: 11/29/2022] Open
Abstract
Chaperones of the Hsp100/Clp family represent major components of protein homeostasis, conferring maintenance of protein activity under stress. The ClpB-type members of the family, present in bacteria, fungi, and plants, are able to resolubilize aggregated proteins. The mitochondrial member of the ClpB family in Saccharomyces cerevisiae is Hsp78. Although Hsp78 has been shown to contribute to proteostasis in elevated temperatures, the biochemical mechanisms underlying this mitochondria-specific thermotolerance are still largely unclear. To identify endogenous chaperone substrate proteins, here, we generated an Hsp78-ATPase mutant with stabilized substrate-binding behavior. We used two stable isotope labeling–based quantitative mass spectrometry approaches to analyze the role of Hsp78 during heat stress–induced mitochondrial protein aggregation and disaggregation on a proteomic level. We first identified the endogenous substrate spectrum of the Hsp78 chaperone, comprising a wide variety of proteins related to metabolic functions including energy production and protein synthesis, as well as other chaperones, indicating its crucial functions in mitochondrial stress resistance. We then compared these interaction data with aggregation and disaggregation processes in mitochondria under heat stress, which revealed specific aggregation-prone protein populations and demonstrated the direct quantitative impact of Hsp78 on stress-dependent protein solubility under different conditions. We conclude that Hsp78, together with its cofactors, represents a recovery system that protects major mitochondrial metabolic functions during heat stress as well as restores protein biogenesis capacity after the return to normal conditions.
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14
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Morehouse JP, Baker TA, Sauer RT. FtsH degrades dihydrofolate reductase by recognizing a partially folded species. Protein Sci 2022; 31:e4410. [PMID: 36630366 PMCID: PMC9601784 DOI: 10.1002/pro.4410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/21/2022] [Accepted: 07/24/2022] [Indexed: 01/14/2023]
Abstract
AAA+ proteolytic machines play essential roles in maintaining and rebalancing the cellular proteome in response to stress, developmental cues, and environmental changes. Of the five AAA+ proteases in Escherichia coli, FtsH is unique in its attachment to the inner membrane and its function in degrading both membrane and cytosolic proteins. E. coli dihydrofolate reductase (DHFR) is a stable and biophysically well-characterized protein, which a previous study found resisted FtsH degradation despite the presence of an ssrA degron. By contrast, we find that FtsH degrades DHFR fused to a long peptide linker and ssrA tag. Surprisingly, we also find that FtsH degrades DHFR with shorter linkers and ssrA tag, and without any linker or tag. Thus, FtsH must be able to recognize a sequence element or elements within DHFR. We find that FtsH degradation of DHFR is noncanonical in the sense that it does not rely upon recognition of an unstructured polypeptide at or near the N-terminus or C-terminus of the substrate. Results using peptide-array experiments, mutant DHFR proteins, and fusion proteins suggest that FtsH recognizes an internal sequence in a species of DHFR that is partially unfolded. Overall, our findings provide insight into substrate recognition by FtsH and indicate that its degradation capacity is broader than previously reported.
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Affiliation(s)
- Juhee P. Morehouse
- Department of BiologyMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Tania A. Baker
- Department of BiologyMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Robert T. Sauer
- Department of BiologyMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
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15
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Kudzhaev AM, Andrianova AG, Gustchina AE, Smirnov IV, Rotanova TV. ATP-Dependent Lon Proteases in the Cellular Protein Quality Control System. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2022. [DOI: 10.1134/s1068162022040136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Kang Y, Lee K, Hoshikawa K, Kang M, Jang S. Molecular Bases of Heat Stress Responses in Vegetable Crops With Focusing on Heat Shock Factors and Heat Shock Proteins. FRONTIERS IN PLANT SCIENCE 2022; 13:837152. [PMID: 35481144 PMCID: PMC9036485 DOI: 10.3389/fpls.2022.837152] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/09/2022] [Indexed: 05/09/2023]
Abstract
The effects of the climate change including an increase in the average global temperatures, and abnormal weather events such as frequent and severe heatwaves are emerging as a worldwide ecological concern due to their impacts on plant vegetation and crop productivity. In this review, the molecular processes of plants in response to heat stress-from the sensing of heat stress, the subsequent molecular cascades associated with the activation of heat shock factors and their primary targets (heat shock proteins), to the cellular responses-have been summarized with an emphasis on the classification and functions of heat shock proteins. Vegetables contain many essential vitamins, minerals, antioxidants, and fibers that provide many critical health benefits to humans. The adverse effects of heat stress on vegetable growth can be alleviated by developing vegetable crops with enhanced thermotolerance with the aid of various genetic tools. To achieve this goal, a solid understanding of the molecular and/or cellular mechanisms underlying various responses of vegetables to high temperature is imperative. Therefore, efforts to identify heat stress-responsive genes including those that code for heat shock factors and heat shock proteins, their functional roles in vegetable crops, and also their application to developing vegetables tolerant to heat stress are discussed.
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Affiliation(s)
- Yeeun Kang
- World Vegetable Center Korea Office, Wanju-gun, South Korea
| | - Kwanuk Lee
- National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), Wanju-gun, South Korea
| | - Ken Hoshikawa
- Biological Resources and Post-harvest Division, Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Japan
| | | | - Seonghoe Jang
- World Vegetable Center Korea Office, Wanju-gun, South Korea
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17
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Matavacas J, von Wachenfeldt C. Update on the Protein Homeostasis Network in Bacillus subtilis. Front Microbiol 2022; 13:865141. [PMID: 35350626 PMCID: PMC8957991 DOI: 10.3389/fmicb.2022.865141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Protein homeostasis is fundamental to cell function and survival. It relies on an interconnected network of processes involving protein synthesis, folding, post-translational modification and degradation as well as regulators of these processes. Here we provide an update on the roles, regulation and subcellular localization of the protein homeostasis machinery in the Gram-positive model organism Bacillus subtilis. We discuss emerging ideas and current research gaps in the field that, if tackled, increase our understanding of how Gram-positive bacteria, including several human pathogens, maintain protein homeostasis and cope with stressful conditions that challenge their survival.
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18
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Staphylococcal ClpXP protease targets the cellular antioxidant system to eliminate fitness-compromised cells in stationary phase. Proc Natl Acad Sci U S A 2021; 118:2109671118. [PMID: 34782466 DOI: 10.1073/pnas.2109671118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2021] [Indexed: 01/08/2023] Open
Abstract
The transition from growth to stationary phase is a natural response of bacteria to starvation and stress. When stress is alleviated and more favorable growth conditions return, bacteria resume proliferation without a significant loss in fitness. Although specific adaptations that enhance the persistence and survival of bacteria in stationary phase have been identified, mechanisms that help maintain the competitive fitness potential of nondividing bacterial populations have remained obscure. Here, we demonstrate that staphylococci that enter stationary phase following growth in media supplemented with excess glucose, undergo regulated cell death to maintain the competitive fitness potential of the population. Upon a decrease in extracellular pH, the acetate generated as a byproduct of glucose metabolism induces cytoplasmic acidification and extensive protein damage in nondividing cells. Although cell death ensues, it does not occur as a passive consequence of protein damage. Instead, we demonstrate that the expression and activity of the ClpXP protease is induced, resulting in the degeneration of cellular antioxidant capacity and, ultimately, cell death. Under these conditions, inactivation of either clpX or clpP resulted in the extended survival of unfit cells in stationary phase, but at the cost of maintaining population fitness. Finally, we show that cell death from antibiotics that interfere with bacterial protein synthesis can also be partly ascribed to the corresponding increase in clpP expression and activity. The functional conservation of ClpP in eukaryotes and bacteria suggests that ClpP-dependent cell death and fitness maintenance may be a widespread phenomenon in these domains of life.
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19
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Division of labor between the pore-1 loops of the D1 and D2 AAA+ rings coordinates substrate selectivity of the ClpAP protease. J Biol Chem 2021; 297:101407. [PMID: 34780718 PMCID: PMC8666677 DOI: 10.1016/j.jbc.2021.101407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022] Open
Abstract
ClpAP, an ATP-dependent protease consisting of ClpA, a double-ring hexameric unfoldase of the ATPases associated with diverse cellular activities superfamily, and the ClpP peptidase, degrades damaged and unneeded proteins to support cellular proteostasis. ClpA recognizes many protein substrates directly, but it can also be regulated by an adapter, ClpS, that modifies ClpA’s substrate profile toward N-degron substrates. Conserved tyrosines in the 12 pore-1 loops lining the central channel of the stacked D1 and D2 rings of ClpA are critical for degradation, but the roles of these residues in individual steps during direct or adapter-mediated degradation are poorly understood. Using engineered ClpA hexamers with zero, three, or six pore-1 loop mutations in each ATPases associated with diverse cellular activities superfamily ring, we found that active D1 pore loops initiate productive engagement of substrates, whereas active D2 pore loops are most important for mediating the robust unfolding of stable native substrates. In complex with ClpS, active D1 pore loops are required to form a high affinity ClpA•ClpS•substrate complex, but D2 pore loops are needed to “tug on” and remodel ClpS to transfer the N-degron substrate to ClpA. Overall, we find that the pore-1 loop tyrosines in D1 are critical for direct substrate engagement, whereas ClpS-mediated substrate delivery requires unique contributions from both the D1 and D2 pore loops. In conclusion, our study illustrates how pore loop engagement, substrate capture, and powering of the unfolding/translocation steps are distributed between the two rings of ClpA, illuminating new mechanistic features that may be common to double-ring protein unfolding machines.
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20
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DnaJ and ClpX are required for HitRS and HssRS two-component system signaling in Bacillus anthracis. Infect Immun 2021; 90:e0056021. [PMID: 34748369 DOI: 10.1128/iai.00560-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus anthracis is the causative agent of anthrax. This Gram-positive bacterium poses a substantial risk to human health due to high mortality rates and the potential for malicious use as a bioterror weapon. To survive within the vertebrate host, B. anthracis relies on two-component system (TCS) signaling to sense host-induced stresses and respond to alterations in the environment through changes in target gene expression. HitRS and HssRS are cross-regulating TCSs in B. anthracis that respond to cell envelope disruptions and high heme levels, respectively. In this study, an unbiased and targeted genetic selection was designed to identify gene products that are involved in HitRS and HssRS signaling. This selection led to the identification of inactivating mutations within dnaJ and clpX that disrupt HitRS- and HssRS-dependent gene expression. DnaJ and ClpX are the substrate-binding subunits of the DnaJK protein chaperone and ClpXP protease, respectively. DnaJ regulates the levels of HitR and HitS to facilitate signal transduction, while ClpX specifically regulates HitS levels. Together these results reveal that the protein homeostasis regulators, DnaJ and ClpX, function to maintain B. anthracis signal transduction activities through TCS regulation. One sentence summary: Use of a genetic selection strategy to identify modulators of two-component system signaling in Bacillus anthracis.
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21
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Mohiuddin SG, Ghosh S, Ngo HG, Sensenbach S, Karki P, Dewangan NK, Angardi V, Orman MA. Cellular Self-Digestion and Persistence in Bacteria. Microorganisms 2021; 9:2269. [PMID: 34835393 PMCID: PMC8626048 DOI: 10.3390/microorganisms9112269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/30/2022] Open
Abstract
Cellular self-digestion is an evolutionarily conserved process occurring in prokaryotic cells that enables survival under stressful conditions by recycling essential energy molecules. Self-digestion, which is triggered by extracellular stress conditions, such as nutrient depletion and overpopulation, induces degradation of intracellular components. This self-inflicted damage renders the bacterium less fit to produce building blocks and resume growth upon exposure to fresh nutrients. However, self-digestion may also provide temporary protection from antibiotics until the self-digestion-mediated damage is repaired. In fact, many persistence mechanisms identified to date may be directly or indirectly related to self-digestion, as these processes are also mediated by many degradative enzymes, including proteases and ribonucleases (RNases). In this review article, we will discuss the potential roles of self-digestion in bacterial persistence.
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Affiliation(s)
| | | | | | | | | | | | | | - Mehmet A. Orman
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX 77004, USA; (S.G.M.); (S.G.); (H.G.N.); (S.S.); (P.K.); (N.K.D.); (V.A.)
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22
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Dong S, Chen H, Zhou Q, Liao N. Protein degradation control and regulation of bacterial survival and pathogenicity: the role of protein degradation systems in bacteria. Mol Biol Rep 2021; 48:7575-7585. [PMID: 34655017 DOI: 10.1007/s11033-021-06744-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Protein degradation systems play crucial roles in all the kingdoms of life. Their natural function is to eliminate proteins that are improperly synthesized, damaged, aggregated, or short-lived, ensuring the timely and accurate regulation of the response to abrupt environmental changes. Thus, proteolysis plays an important role in protein homeostasis, quality control, and the control of regulatory processes, such as adaptation and cell development. Except for the lysosome, ATPases Associated with various cellular Activities (AAA+) ATPase-protease complex is another major protein degradation system in the cell. METHODS AND RESULTS The AAA+ ATPase-protease complex is a giant energy-dependent protease complex found in almost all kinds of cells, including bacteria, archaea and eukarya. Based on sequence analysis of ClpQ (HslV) and 20S proteasome beta subunits, it was found that bacterial ClpQ possess multiple same highly conserved motifs with 20S proteasome beta subunits of archaea and eukaryote. In this review, we also discussed the structure and functional mechanism, protein degradation signals and pathogenic role of proteasome / Clp protease complex in prokaryotes. CONCLUSION Bacterial protein degradation systems play important roles in stress tolerance, protein quality control, DNA protection, transcription and pathogenicity of bacteria. But our current knowledge of the bacterial protease system is incomplete, and further research into the Clp protease complex and associated protein degradation signals will extend our understanding of the metabolism, physiology, reproduction, and pathogenicity of bacteria.
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Affiliation(s)
- Shilei Dong
- Department of Clinical Laboratory, Zhejiang Hospital, Hangzhou, 310013, China
| | - Honghu Chen
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Qingxue Zhou
- Department of Clinical Laboratory, Hangzhou Women's Hospital (Hangzhou Maternity and Child Health Care Hospital), Hangzhou, 310008, China
| | - Ningbo Liao
- College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang, 330045, China.
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23
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Yang T, Zhang T, Zhou X, Wang P, Gan J, Song B, Yang S, Yang CG. Dysregulation of ClpP by Small-Molecule Activators Used Against Xanthomonas oryzae pv. oryzae Infections. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:7545-7553. [PMID: 34218658 DOI: 10.1021/acs.jafc.1c01470] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Rice bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (Xoo) is considered a destructive plant bacterial disease. The looming crisis of antibiotic resistance necessitates the discovery of antibiotics with new modes of action. Activated caseinolytic protease P (ClpP) can degrade bacterial FtsZ proteins that are essential for cell division; thus, we hypothesized that small-molecule-induced dysregulation of XooClpP may result in degradation of XooFtsZ to treat leaf blight diseases. In this work, we have determined the crystal structures of XooClpP, and its mutant bound with ADEP4, which revealed the action modes of XooClpP assemblies and XooFtsZ degradation by dysregulated XooClpP in the presence of small-molecule activators, such as ONC212 and ADEP4. Additionally, an antibacterial assessment demonstrated that ONC212 displays excellent activity against Xoo and prevents rice bacterial leaf blight in vivo. Thus, these unique antibacterial effects of small-molecule activators of XooClpP represent a potential strategy for the development of agricultural antibiotics by targeting bacterial ClpP.
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Affiliation(s)
- Teng Yang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China
- The Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Tao Zhang
- The Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xiang Zhou
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China
| | - Pengyu Wang
- The Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Jianhua Gan
- School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Baoan Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China
| | - Song Yang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China
| | - Cai-Guang Yang
- The Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
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24
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Jakhu P, Sharma P, Yadav IS, Kaur P, Kaur S, Chhuneja P, Singh K. Cloning, expression analysis and In silico characterization of HSP101: a potential player conferring heat stress in Aegilops speltoides (Tausch) Gren. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2021; 27:1205-1218. [PMID: 34220041 PMCID: PMC8212197 DOI: 10.1007/s12298-021-01005-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/22/2021] [Accepted: 05/18/2021] [Indexed: 05/05/2023]
Abstract
UNLABELLED Heat shock protein (HSP101) function as molecular chaperones and confer thermotolerance to plants. In the present investigation, identification, comprehensive expression analysis, phylogeny and protein modelling of HSP101 gene has been done in Aegilops speltoides accession Pau3583. In the present study, we cloned and in silico characterized a HSP101C gene designated as AsHSP101C-Pau3583. AsHSP101C-Pau3583 is 4180 bp long with seven exons and six introns and encoded a polypeptide of 910 amino acids predicted by FGENESH. We have identified 58 SNPs between the AsHSP101C-Pau3583 and reference gene sequence extracted from Ae. speltoides TGAC assembly. Real-time RT-PCR analysis of expression levels of HSP101 gene in two wheat genotypes under heat stress revealed that gene namely HSP101C was up-regulated in Aegilops speltoides acc. Pau3583 by > fourfold in comparison to Triticum aestivum cv. PBW343 under heat stress signifies that it plays a role in conferring heat tolerance. Sequence comparison and phylogenetic analysis of AsHSP101C-Pau3583 with seven wheat homologs Triticum aestivum, Aegilops speltoides (TGAC), Triticum durum cv Cappelli, Triticum durum cv Strongfield, Triticum monococcum, Aegilops tauschii and Triticum urartu showed significant similarities with highly conserved coding regions and functional domains (AAA, AAA + 2, ClpB domains), suggesting the conserved function of HSP101C in different species. The illustration of the protein models of HSP101C in homologs provided information for the ATP-binding motifs within the nucleotide binding domains (NBD), specific for the chaperone activity. These findings are important and identified SNPs could be used for designing markers for ensuring the transfer of AsHSP101C-Pau3583 gene into hexaploid wheat and its role in heat tolerance. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s12298-021-01005-2.
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Affiliation(s)
- Pratibha Jakhu
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Priti Sharma
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Inderjit Singh Yadav
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Parampreet Kaur
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Satinder Kaur
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Parveen Chhuneja
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
| | - Kuldeep Singh
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141 004 India
- National Bureau of Plant Genetic Resources, Delhi, 110012 India
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25
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Dighe SN, van Akker SR, Mathew M, Perera M, Collet TA. Discovery of a Novel Antimicrobial Agent by the Virtual Screening of a Library of Small Molecules. Mol Inform 2021; 40:e2100035. [PMID: 33891375 DOI: 10.1002/minf.202100035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 11/12/2022]
Abstract
A virtual screening approach based upon a combination of docking and pharmacophore methods was utilized on a library of 1.4 million molecules to identify novel antimicrobial agents, which may potentially act via inhibition of the caseinolytic protease. Using this method, compound 6 was found to be bactericidal against three staphylococcal species (minimum inhibitory concentration (MIC)=4-16 μg/mL). Further, subsequent structural optimization of 6 led to the identification of compound 24, which was shown to be the most potent analog within the series (MIC=4 μg/mL) and outperforming the antibiotic controls for two of the staphylococcal species. The newly discovered antimicrobial agent (24) demonstrated excellent in silico ADME properties and was non-toxic when tested on two human skin cell lines. As such, compound 24 has the potential for use as a lead molecule in the development of a novel class of antimicrobial agents.
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Affiliation(s)
- Satish N Dighe
- Queensland University of Technology, Institute of Health & Biomedical Innovation, 60 Musk Avenue, Kelvin Grove, Brisbane, QLD, Australia, 4059
| | - Suzannah R van Akker
- Queensland University of Technology, Institute of Health & Biomedical Innovation, 60 Musk Avenue, Kelvin Grove, Brisbane, QLD, Australia, 4059
| | - Marina Mathew
- Queensland University of Technology, Institute of Health & Biomedical Innovation, 60 Musk Avenue, Kelvin Grove, Brisbane, QLD, Australia, 4059
| | - Madusha Perera
- Queensland University of Technology, Institute of Health & Biomedical Innovation, 60 Musk Avenue, Kelvin Grove, Brisbane, QLD, Australia, 4059
| | - Trudi A Collet
- Queensland University of Technology, Institute of Health & Biomedical Innovation, 60 Musk Avenue, Kelvin Grove, Brisbane, QLD, Australia, 4059
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Kotrasová V, Keresztesová B, Ondrovičová G, Bauer JA, Havalová H, Pevala V, Kutejová E, Kunová N. Mitochondrial Kinases and the Role of Mitochondrial Protein Phosphorylation in Health and Disease. Life (Basel) 2021; 11:life11020082. [PMID: 33498615 PMCID: PMC7912454 DOI: 10.3390/life11020082] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023] Open
Abstract
The major role of mitochondria is to provide cells with energy, but no less important are their roles in responding to various stress factors and the metabolic changes and pathological processes that might occur inside and outside the cells. The post-translational modification of proteins is a fast and efficient way for cells to adapt to ever changing conditions. Phosphorylation is a post-translational modification that signals these changes and propagates these signals throughout the whole cell, but it also changes the structure, function and interaction of individual proteins. In this review, we summarize the influence of kinases, the proteins responsible for phosphorylation, on mitochondrial biogenesis under various cellular conditions. We focus on their role in keeping mitochondria fully functional in healthy cells and also on the changes in mitochondrial structure and function that occur in pathological processes arising from the phosphorylation of mitochondrial proteins.
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Affiliation(s)
- Veronika Kotrasová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
| | - Barbora Keresztesová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
- First Faculty of Medicine, Institute of Biology and Medical Genetics, Charles University, 128 00 Prague, Czech Republic
| | - Gabriela Ondrovičová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
| | - Jacob A. Bauer
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
| | - Henrieta Havalová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
| | - Vladimír Pevala
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
| | - Eva Kutejová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
- Correspondence: (E.K.); (N.K.)
| | - Nina Kunová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 845 51 Bratislava, Slovakia; (V.K.); (B.K.); (G.O.); (J.A.B.); (H.H.); (V.P.)
- First Faculty of Medicine, Institute of Biology and Medical Genetics, Charles University, 128 00 Prague, Czech Republic
- Correspondence: (E.K.); (N.K.)
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Weiten A, Kalvelage K, Becker P, Reinhardt R, Hurek T, Reinhold-Hurek B, Rabus R. Complete Genomes of the Anaerobic Degradation Specialists Aromatoleum petrolei ToN1T and Aromatoleum bremense PbN1T. Microb Physiol 2021; 31:16-35. [PMID: 33477134 DOI: 10.1159/000513167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 11/17/2020] [Indexed: 11/19/2022]
Abstract
The betaproteobacterial genus Aromatoleum comprises facultative denitrifiers specialized in the anaerobic degradation of recalcitrant organic compounds (aromatic and terpenoid). This study reports on the complete and manually annotated genomes of Ar. petrolei ToN1T (5.41 Mbp) and Ar. bremense PbN1T (4.38 Mbp), which cover the phylogenetic breadth of the genus Aromatoleum together with previously genome sequenced Ar. aromaticum EbN1T [Rabus et al., Arch Microbiol. 2005 Jan;183(1):27-36]. The gene clusters for the anaerobic degradation of aromatic and terpenoid (strain ToN1T only) compounds are scattered across the genomes of strains ToN1T and PbN1T. The richness in mobile genetic elements is shared with other Aromatoleum spp., substantiating that horizontal gene transfer should have been a major driver in shaping the genomes of this genus. The composite catabolic network of strains ToN1T and PbN1T comprises 88 proteins, the coding genes of which occupy 86.1 and 76.4 kbp (1.59 and 1.75%) of the respective genome. The strain-specific gene clusters for anaerobic degradation of ethyl-/propylbenzene (strain PbN1T) and toluene/monoterpenes (strain ToN1T) share high similarity with their counterparts in Ar. aromaticum strains EbN1T and pCyN1, respectively. Glucose is degraded via the ED-pathway in strain ToN1T, while gluconeogenesis proceeds via the reverse EMP-pathway in strains ToN1T, PbN1T, and EbN1T. The diazotrophic, endophytic lifestyle of closest related genus Azoarcus is known to be associated with nitrogenase and type-6 secretion system (T6SS). By contrast, strains ToN1T, PbN1T, and EbN1T lack nif genes for nitrogenase (including cofactor synthesis and enzyme maturation). Moreover, strains PbN1T and EbN1T do not possess tss genes for T6SS, while strain ToN1T does and facultative endophytic "Aromatoleum" sp. CIB is known to even have both. These findings underpin the functional heterogeneity among Aromatoleum members, correlating with the high plasticity of their genomes.
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Affiliation(s)
- Arne Weiten
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Kristin Kalvelage
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Patrick Becker
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Richard Reinhardt
- Max-Planck-Genome-Centre Cologne, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Thomas Hurek
- Department of Microbe-Plant Interactions, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Barbara Reinhold-Hurek
- Department of Microbe-Plant Interactions, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Ralf Rabus
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany,
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28
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LaBreck CJ, Trebino CE, Ferreira CN, Morrison JJ, DiBiasio EC, Conti J, Camberg JL. Degradation of MinD oscillator complexes by Escherichia coli ClpXP. J Biol Chem 2020; 296:100162. [PMID: 33288679 PMCID: PMC7857489 DOI: 10.1074/jbc.ra120.013866] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 11/24/2022] Open
Abstract
MinD is a cell division ATPase in Escherichia coli that oscillates from pole to pole and regulates the spatial position of the cell division machinery. Together with MinC and MinE, the Min system restricts assembly of the FtsZ-ring to midcell, oscillating between the opposite ends of the cell and preventing FtsZ-ring misassembly at the poles. Here, we show that the ATP-dependent bacterial proteasome complex ClpXP degrades MinD in reconstituted degradation reactions in vitro and in vivo through direct recognition of the MinD N-terminal region. MinD degradation is enhanced during stationary phase, suggesting that ClpXP regulates levels of MinD in cells that are not actively dividing. ClpXP is a major regulator of growth phase–dependent proteins, and these results suggest that MinD levels are also controlled during stationary phase. In vitro, MinC and MinD are known to coassemble into linear polymers; therefore, we monitored copolymers assembled in vitro after incubation with ClpXP and observed that ClpXP promotes rapid MinCD copolymer destabilization and direct MinD degradation by ClpXP. The N terminus of MinD, including residue Arg 3, which is near the ATP-binding site in sequence, is critical for degradation by ClpXP. Together, these results demonstrate that ClpXP degradation modifies conformational assemblies of MinD in vitro and depresses Min function in vivo during periods of reduced proliferation.
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Affiliation(s)
- Christopher J LaBreck
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Catherine E Trebino
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Colby N Ferreira
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Josiah J Morrison
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Eric C DiBiasio
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Joseph Conti
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Jodi L Camberg
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA.
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29
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Ceyssens PJ, De Smet J, Wagemans J, Akulenko N, Klimuk E, Hedge S, Voet M, Hendrix H, Paeshuyse J, Landuyt B, Xu H, Blanchard J, Severinov K, Lavigne R. The Phage-Encoded N-Acetyltransferase Rac Mediates Inactivation of Pseudomonas aeruginosa Transcription by Cleavage of the RNA Polymerase Alpha Subunit. Viruses 2020; 12:v12090976. [PMID: 32887488 PMCID: PMC7552054 DOI: 10.3390/v12090976] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 12/20/2022] Open
Abstract
In this study, we describe the biological function of the phage-encoded protein RNA polymerase alpha subunit cleavage protein (Rac), a predicted Gcn5-related acetyltransferase encoded by phiKMV-like viruses. These phages encode a single-subunit RNA polymerase for transcription of their late (structure- and lysis-associated) genes, whereas the bacterial RNA polymerase is used at the earlier stages of infection. Rac mediates the inactivation of bacterial transcription by introducing a specific cleavage in the α subunit of the bacterial RNA polymerase. This cleavage occurs within the flexible linker sequence and disconnects the C-terminal domain, required for transcription initiation from most highly active cellular promoters. To achieve this, Rac likely taps into a novel post-translational modification (PTM) mechanism within the host Pseudomonas aeruginosa. From an evolutionary perspective, this novel phage-encoded regulation mechanism confirms the importance of PTMs in the prokaryotic metabolism and represents a new way by which phages can hijack the bacterial host metabolism.
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Affiliation(s)
- Pieter-Jan Ceyssens
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Jeroen De Smet
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Jeroen Wagemans
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Natalia Akulenko
- Institute of Molecular Genetics, Russian Academy of Sciences, 119334 Moscow, Russia; (N.A.); (E.K.); (K.S.)
| | - Evgeny Klimuk
- Institute of Molecular Genetics, Russian Academy of Sciences, 119334 Moscow, Russia; (N.A.); (E.K.); (K.S.)
| | - Subray Hedge
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA; (S.H.); (H.X.); (J.B.)
| | - Marleen Voet
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Hanne Hendrix
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Jan Paeshuyse
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
| | - Bart Landuyt
- Department of Biology, KU Leuven, 3000 Leuven, Belgium;
| | - Hua Xu
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA; (S.H.); (H.X.); (J.B.)
| | - John Blanchard
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA; (S.H.); (H.X.); (J.B.)
| | - Konstantin Severinov
- Institute of Molecular Genetics, Russian Academy of Sciences, 119334 Moscow, Russia; (N.A.); (E.K.); (K.S.)
| | - Rob Lavigne
- Department of Biosystems, KU Leuven, 3000 Leuven, Belgium; (P.-J.C.); (J.D.S.); (J.W.); (M.V.); (H.H.); (J.P.)
- Correspondence: ; Tel.: +32-16-379-524
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30
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Lakshmanan A, Jin Z, Nety SP, Sawyer DP, Lee-Gosselin A, Malounda D, Swift MB, Maresca D, Shapiro MG. Acoustic biosensors for ultrasound imaging of enzyme activity. Nat Chem Biol 2020; 16:988-996. [PMID: 32661379 PMCID: PMC7713704 DOI: 10.1038/s41589-020-0591-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 06/12/2020] [Indexed: 12/19/2022]
Abstract
Visualizing biomolecular and cellular processes inside intact living organisms is a major goal of chemical biology. However, existing molecular biosensors, based primarily on fluorescent emission, have limited utility in this context due to the scattering of light by tissue. In contrast, ultrasound can easily image deep tissue with high spatiotemporal resolution, but lacks the biosensors needed to connect its contrast to the activity of specific biomolecules such as enzymes. To overcome this limitation, we introduce the first genetically encodable acoustic biosensors-molecules that 'light up' in ultrasound imaging in response to protease activity. These biosensors are based on a unique class of air-filled protein nanostructures called gas vesicles, which we engineered to produce nonlinear ultrasound signals in response to the activity of three different protease enzymes. We demonstrate the ability of these biosensors to be imaged in vitro, inside engineered probiotic bacteria, and in vivo in the mouse gastrointestinal tract.
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Affiliation(s)
- Anupama Lakshmanan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Zhiyang Jin
- Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Suchita P Nety
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Daniel P Sawyer
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Audrey Lee-Gosselin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Dina Malounda
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Mararet B Swift
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - David Maresca
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Imaging Physics, Delft University of Technology, Delft, Netherlands
| | - Mikhail G Shapiro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.
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31
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During Oxidative Stress the Clp Proteins of Escherichia coli Ensure that Iron Pools Remain Sufficient To Reactivate Oxidized Metalloenzymes. J Bacteriol 2020; 202:JB.00235-20. [PMID: 32601069 DOI: 10.1128/jb.00235-20] [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: 04/23/2020] [Accepted: 06/20/2020] [Indexed: 11/20/2022] Open
Abstract
Hydrogen peroxide (H2O2) is formed in natural environments by both biotic and abiotic processes. It easily enters the cytoplasms of microorganisms, where it can disrupt growth by inactivating iron-dependent enzymes. It also reacts with the intracellular iron pool, generating hydroxyl radicals that can lethally damage DNA. Therefore, virtually all bacteria possess H2O2-responsive transcription factors that control defensive regulons. These typically include catalases and peroxidases that scavenge H2O2 Another common component is the miniferritin Dps, which sequesters loose iron and thereby suppresses hydroxyl-radical formation. In this study, we determined that Escherichia coli also induces the ClpS and ClpA proteins of the ClpSAP protease complex. Mutants that lack this protease, plus its partner, ClpXP protease, cannot grow when H2O2 levels rise. The growth defect was traced to the inactivity of dehydratases in the pathway of branched-chain amino acid synthesis. These enzymes rely on a solvent-exposed [4Fe-4S] cluster that H2O2 degrades. In a typical cell the cluster is continuously repaired, but in the clpSA clpX mutant the repair process is defective. We determined that this disability is due to an excessively small iron pool, apparently due to the oversequestration of iron by Dps. Dps was previously identified as a substrate of both the ClpSAP and ClpXP proteases, and in their absence its levels are unusually high. The implication is that the stress response to H2O2 has evolved to strike a careful balance, diminishing iron pools enough to protect the DNA but keeping them substantial enough that critical iron-dependent enzymes can be repaired.IMPORTANCE Hydrogen peroxide mediates the toxicity of phagocytes, lactic acid bacteria, redox-cycling antibiotics, and photochemistry. The underlying mechanisms all involve its reaction with iron atoms, whether in enzymes or on the surface of DNA. Accordingly, when bacteria perceive toxic H2O2, they activate defensive tactics that are focused on iron metabolism. In this study, we identify a conundrum: DNA is best protected by the removal of iron from the cytoplasm, but this action impairs the ability of the cell to reactivate its iron-dependent enzymes. The actions of the Clp proteins appear to hedge against the oversequestration of iron by the miniferritin Dps. This buffering effect is important, because E. coli seeks not just to survive H2O2 but to grow in its presence.
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Long-range intramolecular allostery and regulation in the dynein-like AAA protein Mdn1. Proc Natl Acad Sci U S A 2020; 117:18459-18469. [PMID: 32694211 DOI: 10.1073/pnas.2002792117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mdn1 is an essential mechanoenzyme that uses the energy from ATP hydrolysis to physically reshape and remodel, and thus mature, the 60S subunit of the ribosome. This massive (>500 kDa) protein has an N-terminal AAA (ATPase associated with diverse cellular activities) ring, which, like dynein, has six ATPase sites. The AAA ring is followed by large (>2,000 aa) linking domains that include an ∼500-aa disordered (D/E-rich) region, and a C-terminal substrate-binding MIDAS domain. Recent models suggest that intramolecular docking of the MIDAS domain onto the AAA ring is required for Mdn1 to transmit force to its ribosomal substrates, but it is not currently understood what role the linking domains play, or why tethering the MIDAS domain to the AAA ring is required for protein function. Here, we use chemical probes, single-particle electron microscopy, and native mass spectrometry to study the AAA and MIDAS domains separately or in combination. We find that Mdn1 lacking the D/E-rich and MIDAS domains retains ATP and chemical probe binding activities. Free MIDAS domain can bind to the AAA ring of this construct in a stereo-specific bimolecular interaction, and, interestingly, this binding reduces ATPase activity. Whereas intramolecular MIDAS docking appears to require a treatment with a chemical inhibitor or preribosome binding, bimolecular MIDAS docking does not. Hence, tethering the MIDAS domain to the AAA ring serves to prevent, rather than promote, MIDAS docking in the absence of inducing signals.
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33
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Lopez KE, Rizo AN, Tse E, Lin J, Scull NW, Thwin AC, Lucius AL, Shorter J, Southworth DR. Conformational plasticity of the ClpAP AAA+ protease couples protein unfolding and proteolysis. Nat Struct Mol Biol 2020; 27:406-416. [PMID: 32313240 PMCID: PMC7529148 DOI: 10.1038/s41594-020-0409-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 03/09/2020] [Indexed: 11/09/2022]
Abstract
The ClpAP complex is a conserved bacterial protease that unfolds and degrades proteins targeted for destruction. The ClpA double-ring hexamer powers substrate unfolding and translocation into the ClpP proteolytic chamber. Here, we determined high-resolution structures of wild-type Escherichia coli ClpAP undergoing active substrate unfolding and proteolysis. A spiral of pore loop-substrate contacts spans both ClpA AAA+ domains. Protomers at the spiral seam undergo nucleotide-specific rearrangements, supporting substrate translocation. IGL loops extend flexibly to bind the planar, heptameric ClpP surface with the empty, symmetry-mismatched IGL pocket maintained at the seam. Three different structures identify a binding-pocket switch by the IGL loop of the lowest positioned protomer, involving release and re-engagement with the clockwise pocket. This switch is coupled to a ClpA rotation and a network of conformational changes across the seam, suggesting that ClpA can rotate around the ClpP apical surface during processive steps of translocation and proteolysis.
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Affiliation(s)
- Kyle E Lopez
- Graduate Program in Biophysics, University of California, San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA
| | - Alexandrea N Rizo
- Department of Biochemistry and Biophysics, Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA
- Graduate Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA
| | - Eric Tse
- Department of Biochemistry and Biophysics, Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA
| | - JiaBei Lin
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Nathaniel W Scull
- Department of Chemistry, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Aye C Thwin
- Department of Biochemistry and Biophysics, Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA
| | - Aaron L Lucius
- Department of Chemistry, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel R Southworth
- Department of Biochemistry and Biophysics, Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA.
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Fritze J, Zhang M, Luo Q, Lu X. An overview of the bacterial SsrA system modulating intracellular protein levels and activities. Appl Microbiol Biotechnol 2020; 104:5229-5241. [PMID: 32342145 DOI: 10.1007/s00253-020-10623-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 04/07/2020] [Accepted: 04/13/2020] [Indexed: 12/18/2022]
Abstract
In bacteria, the truncated forms of mRNAs, which usually lack a stop codon, are occasionally generated by premature termination of gene transcription and/or endo- or exonucleolytic cleavage events. Ribosomes proceeding on these molecules stall at the 3' end of the chain and are rescued by a widely distributed mechanism known as trans-translation, which includes two essential elements, ssrA RNA (a special RNA) and SmpB (a small protein). Through this mechanism, the polypeptides translated from truncated mRNAs are marked by a short peptide, known as SsrA tag, at their C-termini and directed to the specific endogenous proteases for C-terminal proteolysis. Based on the deep understanding of the SsrA tagging and degradation mechanisms, recently a series of SsrA-based genetic tools have been developed for gene regulation on the level of post-translation. They are successfully applied for controllable regulation of biological circuits in bacteria. In the present article, we systematically summarize the history, structural characteristics, and functional mechanisms of the SsrA tagging and degrading machineries, as well as their technical uses and limitations.Key Points• SsrA system plays an important role in ribosome rescue in bacteria.• SsrA-based genetic tools are useful for controlling protein levels and activities.
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Affiliation(s)
- Jacques Fritze
- Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,University of Stuttgart, Stuttgart, Germany
| | - Mingyi Zhang
- Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Quan Luo
- Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. .,School of Life Sciences, Hubei University, Wuhan, China.
| | - Xuefeng Lu
- Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. .,Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. .,Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. .,Marine Biology and Biotechnology Laboratory, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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35
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Luo J, Zeng B, Tao C, Lu M, Ren G. ClpP regulates breast cancer cell proliferation, invasion and apoptosis by modulating the Src/PI3K/Akt signaling pathway. PeerJ 2020; 8:e8754. [PMID: 32195060 PMCID: PMC7069407 DOI: 10.7717/peerj.8754] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/14/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Caseinolytic protease P (ClpP), which is located on the inner mitochondrial membrane, degrades mitochondrial proteins damaged by oxidative stress. The role of ClpP varies among tumor types. However, the expression pattern and biological functions of ClpP in breast cancer (BC) have not yet been investigated. METHODS The Cancer Genome Atlas (TCGA) and Kaplan Meier-plotter database were used to analyze the expression level of ClpP in BC tissues, relationships with clinicopathological characteristics, and the influence on the prognosis of BC. Protein and mRNA expression levels of ClpP in BC cell lines and tissues were detected by quantitative real-time PCR, western blot and immunohistochemical (IHC) analyses. The colony formation assay, transwell assay and flow cytometric analysis were performed to assess various functions of ClpP. Western blot analysis was also conducted to determine the mechanism of ClpP. RESULTS ClpP expression was markedly increased in BC cells and tissues. High expression of ClpP was significantly correlated with the T stage, estrogen receptor (ER) expression, and poor recurrence-free survival (RFS) in TCGA and Kaplan Meier-plotter database. ClpP silencing significantly inhibited proliferation, migration, invasion, and promoted apoptosis of BC cells, which resulted in suppression of the Src/PI3K/Akt signaling pathway. The gain-of-function assay confirmed partial these results.
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Affiliation(s)
- Juan Luo
- Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Beilei Zeng
- Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Chunfang Tao
- Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Mengqi Lu
- Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Guosheng Ren
- Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Department of Endocrine and Breast Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Synonymous codon substitutions perturb cotranslational protein folding in vivo and impair cell fitness. Proc Natl Acad Sci U S A 2020; 117:3528-3534. [PMID: 32015130 DOI: 10.1073/pnas.1907126117] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
In the cell, proteins are synthesized from N to C terminus and begin to fold during translation. Cotranslational folding mechanisms are therefore linked to elongation rate, which varies as a function of synonymous codon usage. However, synonymous codon substitutions can affect many distinct cellular processes, which has complicated attempts to deconvolve the extent to which synonymous codon usage can promote or frustrate proper protein folding in vivo. Although previous studies have shown that some synonymous changes can lead to different final structures, other substitutions will likely be more subtle, perturbing predominantly the protein folding pathway without radically altering the final structure. Here we show that synonymous codon substitutions encoding a single essential enzyme lead to dramatically slower cell growth. These mutations do not prevent active enzyme formation; instead, they predominantly alter the protein folding mechanism, leading to enhanced degradation in vivo. These results support a model in which synonymous codon substitutions can impair cell fitness by significantly perturbing cotranslational protein folding mechanisms, despite the chaperoning provided by the cellular protein homeostasis network.
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Kater L, Wagener N, Berninghausen O, Becker T, Neupert W, Beckmann R. Structure of the Bcs1 AAA-ATPase suggests an airlock-like translocation mechanism for folded proteins. Nat Struct Mol Biol 2020; 27:142-149. [DOI: 10.1038/s41594-019-0364-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 12/13/2019] [Indexed: 11/09/2022]
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The molecular principles governing the activity and functional diversity of AAA+ proteins. Nat Rev Mol Cell Biol 2019; 21:43-58. [PMID: 31754261 DOI: 10.1038/s41580-019-0183-6] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2019] [Indexed: 12/26/2022]
Abstract
ATPases associated with diverse cellular activities (AAA+ proteins) are macromolecular machines that convert the chemical energy contained in ATP molecules into powerful mechanical forces to remodel a vast array of cellular substrates, including protein aggregates, macromolecular complexes and polymers. AAA+ proteins have key functionalities encompassing unfolding and disassembly of such substrates in different subcellular localizations and, hence, power a plethora of fundamental cellular processes, including protein quality control, cytoskeleton remodelling and membrane dynamics. Over the past 35 years, many of the key elements required for AAA+ activity have been identified through genetic, biochemical and structural analyses. However, how ATP powers substrate remodelling and whether a shared mechanism underlies the functional diversity of the AAA+ superfamily were uncertain. Advances in cryo-electron microscopy have enabled high-resolution structure determination of AAA+ proteins trapped in the act of processing substrates, revealing a conserved core mechanism of action. It has also become apparent that this common mechanistic principle is structurally adjusted to carry out a diverse array of biological functions. Here, we review how substrate-bound structures of AAA+ proteins have expanded our understanding of ATP-driven protein remodelling.
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Staphylococcus aureus ClpX localizes at the division septum and impacts transcription of genes involved in cell division, T7-secretion, and SaPI5-excision. Sci Rep 2019; 9:16456. [PMID: 31712583 PMCID: PMC6848492 DOI: 10.1038/s41598-019-52823-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 10/12/2019] [Indexed: 11/25/2022] Open
Abstract
In all living cells, molecular chaperones are essential for facilitating folding and unfolding of proteins. ClpX is a highly conserved ATP-dependent chaperone that besides functioning as a classical chaperone can associate with ClpP to form the ClpXP protease. To investigate the relative impact of the ClpXP protease and the ClpX chaperone in cell physiology of the important pathogenic bacterium Staphylococcus aureus, we assessed the transcriptional changes induced by inactivating only ClpXP, or by completely deleting ClpX. This analysis revealed that ClpX has a profound impact on S. aureus cell physiology that is mediated primarily via ClpXP-dependent pathways. As an example, ClpX impacts expression of virulence genes entirely via ClpXP-dependent mechanisms. Furthermore, ClpX controls a high number of genes and sRNAs via pathways involving both ClpXP protease and ClpX chaperone activities; an interesting example being genes promoting excision and replication of the pathogenicity island SaPI5. Independently of ClpP, ClpX, impacts transcription of only a restricted number of genes involved in peptidoglycan synthesis, cell division, and type seven secretion. Finally, we demonstrate that ClpX localizes in single foci in close proximity to the division septum lending support to the idea that ClpX plays a role in S. aureus cell division.
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Bernal I, Römermann J, Flacht L, Lunelli M, Uetrecht C, Kolbe M. Structural analysis of ligand-bound states of the Salmonella type III secretion system ATPase InvC. Protein Sci 2019; 28:1888-1901. [PMID: 31393998 PMCID: PMC6739812 DOI: 10.1002/pro.3704] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 12/21/2022]
Abstract
Translocation of virulence effector proteins through the type III secretion system (T3SS) is essential for the virulence of many medically relevant Gram‐negative bacteria. The T3SS ATPases are conserved components that specifically recognize chaperone–effector complexes and energize effector secretion through the system. It is thought that functional T3SS ATPases assemble into a cylindrical structure maintained by their N‐terminal domains. Using size‐exclusion chromatography coupled to multi‐angle light scattering and native mass spectrometry, we show that in the absence of the N‐terminal oligomerization domain the Salmonella T3SS ATPase InvC can form monomers and dimers in solution. We also present for the first time a 2.05 å resolution crystal structure of InvC lacking the oligomerization domain (InvCΔ79) and map the amino acids suggested for ATPase intersubunit interaction, binding to other T3SS proteins and chaperone–effector recognition. Furthermore, we validate the InvC ATP‐binding site by co‐crystallization of InvCΔ79 with ATPγS (2.65 å) and ADP (2.80 å). Upon ATP‐analogue recognition, these structures reveal remodeling of the ATP‐binding site and conformational changes of two loops located outside of the catalytic site. Both loops face the central pore of the predicted InvC cylinder and are essential for the function of the T3SS ATPase. Our results present a fine functional and structural correlation of InvC and provide further details of the homo‐oligomerization process and ATP‐dependent conformational changes underlying the T3SS ATPase activity. PDB Code(s): 6RAE, 6RAD and 6SDX
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Affiliation(s)
- Ivonne Bernal
- Department of Structural Infection Biology, Center for Structural Systems Biology (CSSB), Helmholtz-Center for Infection Research (HZI), Hamburg, Germany
| | - Jonas Römermann
- Department of Structural Infection Biology, Center for Structural Systems Biology (CSSB), Helmholtz-Center for Infection Research (HZI), Hamburg, Germany
| | - Lara Flacht
- Department of Structural Infection Biology, Center for Structural Systems Biology (CSSB), Helmholtz-Center for Infection Research (HZI), Hamburg, Germany.,Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Michele Lunelli
- Department of Structural Infection Biology, Center for Structural Systems Biology (CSSB), Helmholtz-Center for Infection Research (HZI), Hamburg, Germany
| | - Charlotte Uetrecht
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany.,European XFEL GmbH, Schenefeld, Germany
| | - Michael Kolbe
- Department of Structural Infection Biology, Center for Structural Systems Biology (CSSB), Helmholtz-Center for Infection Research (HZI), Hamburg, Germany.,MIN-Faculty University Hamburg, Hamburg, Germany
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Xue Q. Pathogen proteases and host protease inhibitors in molluscan infectious diseases. J Invertebr Pathol 2019; 166:107214. [PMID: 31348922 DOI: 10.1016/j.jip.2019.107214] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/11/2019] [Accepted: 06/28/2019] [Indexed: 12/17/2022]
Abstract
The development of infectious diseases represents an outcome of dynamic interactions between the disease-producing agent's pathogenicity and the host's self-defense mechanism. Proteases secreted by pathogenic microorganisms and protease inhibitors produced by host species play an important role in the process. This review aimed at summarizing major findings in research on pathogen proteases and host protease inhibitors that had been proposed to be related to the development of mollusk diseases. Metalloproteases and serine proteases respectively belonging to Family M4 and Family S8 of the MEROPS system are among the most studied proteases that may function as virulence factors in mollusk pathogens. On the other hand, a mollusk-specific family (Family I84) of novel serine protease inhibitors and homologues of the tissue inhibitor of metalloprotease have been studied for their potential in the molluscan host defense. In addition, research at the genomic and transcriptomic levels showed that more proteases of pathogens and protease inhibitor of hosts are likely involved in mollusk disease processes. Therefore, the pathological significance of interactions between pathogen proteases and host protease inhibitors in the development of molluscan infectious diseases deserves more research efforts.
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Affiliation(s)
- Qinggang Xue
- Zhejiang Key Lab of Aquatic Germplasm Resources, Zhejiang Wanli University, Ningbo, Zhejiang 315100, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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42
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Coufalova D, Remnant L, Hernychova L, Muller P, Healy A, Kannan S, Westwood N, Verma CS, Vojtesek B, Hupp TR, Houston DR. An inter-subunit protein-peptide interface that stabilizes the specific activity and oligomerization of the AAA+ chaperone Reptin. J Proteomics 2019; 199:89-101. [PMID: 30862565 DOI: 10.1016/j.jprot.2019.02.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/16/2019] [Accepted: 02/23/2019] [Indexed: 12/26/2022]
Abstract
Reptin is a member of the AAA+ superfamily whose members can exist in equilibrium between monomeric apo forms and ligand bound hexamers. Inter-subunit protein-protein interfaces that stabilize Reptin in its oligomeric state are not well-defined. A self-peptide binding assay identified a protein-peptide interface mapping to an inter-subunit "rim" of the hexamer bridged by Tyrosine-340. A Y340A mutation reduced ADP-dependent oligomer formation using a gel filtration assay, suggesting that Y340 forms a dominant oligomer stabilizing side chain. The monomeric ReptinY340A mutant protein exhibited increased activity to its partner protein AGR2 in an ELISA assay, further suggesting that hexamer formation can preclude certain protein interactions. Hydrogen-deuterium exchange mass spectrometry (HDX-MS) demonstrated that the Y340A mutation attenuated deuterium suppression of Reptin in this motif in the presence of ligand. By contrast, the tyrosine motif of Reptin interacts with a shallower pocket in the hetero-oligomeric structure containing Pontin and HDX-MS revealed no obvious role of the Y340 side chain in stabilizing the Reptin-Pontin oligomer. Molecular dynamic simulations (MDS) rationalized how the Y340A mutation impacts upon a normally stabilizing inter-subunit amino acid contact. MDS also revealed how the D299N mutation can, by contrast, remove oligomer de-stabilizing contacts. These data suggest that the Reptin interactome can be regulated by a ligand dependent equilibrium between monomeric and hexameric forms through a hydrophobic inter-subunit protein-protein interaction motif bridged by Tyrosine-340. SIGNIFICANCE: Discovering dynamic protein-protein interactions is a fundamental aim of research in the life sciences. An emerging view of protein-protein interactions in higher eukaryotes is that they are driven by small linear polypeptide sequences; the linear motif. We report on the use of linear-peptide motif screens to discover a relatively high affinity peptide-protein interaction for the AAA+ and pro-oncogenic protein Reptin. This peptide interaction site was shown to form a 'hot-spot' protein-protein interaction site, and validated to be important for ligand-induced oligomerization of the Reptin protein. These biochemical data provide a foundation to understand how single point mutations in Reptin can impact on its oligomerization and protein-protein interaction landscape.
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Affiliation(s)
- Dominika Coufalova
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, 656 53 Brno, Czech Republic
| | - Lucy Remnant
- University of Edinburgh, Institute of Genetics and Molecular Medicine, Edinburgh, Scotland EH4 2XR, United Kingdom
| | - Lenka Hernychova
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, 656 53 Brno, Czech Republic
| | - Petr Muller
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, 656 53 Brno, Czech Republic
| | - Alan Healy
- St Andrews University, St Andrews, Scotland, United Kingdom
| | - Srinivasaraghavan Kannan
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Matrix 07-01 138671, Singapore
| | | | - Chandra S Verma
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Matrix 07-01 138671, Singapore; School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; Department of Biological Sciences, National University of Singapore, 14, Science Drive 4, 117543, Singapore
| | - Borek Vojtesek
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, 656 53 Brno, Czech Republic
| | - Ted R Hupp
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, 656 53 Brno, Czech Republic; University of Edinburgh, Institute of Genetics and Molecular Medicine, Edinburgh, Scotland EH4 2XR, United Kingdom; University of Gdansk, International Centre for Cancer Vaccine Science, ul. Wita Stwosza 63, 80-308 Gdansk, Poland.
| | - Douglas R Houston
- University of Edinburgh, Institute of Quantitative Biology, Biochemistry and Biotechnology, Edinburgh, Scotland EH9 3BF, United Kingdom
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Vinaiphat A, Thongboonkerd V. Chaperonomics in leptospirosis. Expert Rev Proteomics 2018; 15:569-579. [PMID: 30004813 DOI: 10.1080/14789450.2018.1500901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Knowledge of the function of molecular chaperones is required for a better understanding of cellular proteostasis. Nevertheless, such information is currently dispersed as most of previous studies investigated chaperones on a single-angle basis. Recently, a new subdiscipline of chaperonology, namely 'chaperonomics' (defined as 'systematic analysis of chaperone genes, transcripts, proteins, or their interaction networks using omics technologies'), has been emerging to better understand biological, physiological, and pathological roles of chaperones. Areas covered: This review provides broad overviews of bacterial chaperones, heat shock proteins (HSPs), and leptospirosis, and then focuses on recent progress of chaperonomics applied to define roles of HSPs in various pathogenic and saprophytic leptospiral species and serovars. Expert commentary: Comprehensive analysis of leptospiral chaperones/HSPs using a chaperonomics approach holds great promise for better understanding of functional roles of chaperones/HSPs in bacterial survival and disease pathogenesis. Moreover, this new approach may also lead to further development of chaperones/HSPs-based diagnostics and/or vaccine discovery for leptospirosis.
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Affiliation(s)
- Arada Vinaiphat
- a Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok , Thailand
| | - Visith Thongboonkerd
- a Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok , Thailand
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An Iterative, Synthetic Approach To Engineer a High-Performance PhoB-Specific Reporter. Appl Environ Microbiol 2018; 84:AEM.00603-18. [PMID: 29752265 DOI: 10.1128/aem.00603-18] [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: 03/13/2018] [Accepted: 05/03/2018] [Indexed: 11/20/2022] Open
Abstract
Transcriptional reporters are common tools for analyzing either the transcription of a gene of interest or the activity of a specific transcriptional regulator. Unfortunately, the latter application has the shortcoming that native promoters did not evolve as optimal readouts for the activity of a particular regulator. We sought to synthesize an optimized transcriptional reporter for assessing PhoB activity, aiming for maximal "on" expression when PhoB is active, minimal background in the "off" state, and no control elements for other regulators. We designed specific sequences for promoter elements with appropriately spaced PhoB-binding sites, and at 19 additional intervening nucleotide positions for which we did not predict sequence-specific effects, the bases were randomized. Eighty-three such constructs were screened in Vibrio fischeri, enabling us to identify bases at particular randomized positions that significantly correlated with high-level "on" or low-level "off" expression. A second round of promoter design rationally constrained 13 additional positions, leading to a reporter with high-level PhoB-dependent expression, essentially no background, and no other known regulatory elements. As expressed reporters, we used both stable and destabilized variants of green fluorescent protein (GFP), the latter of which has a half-life of 81 min in V. fischeri In culture, PhoB induced the reporter when phosphate was depleted to a concentration below 10 μM. During symbiotic colonization of its host squid, Euprymna scolopes, the reporter indicated heterogeneous phosphate availability in different light-organ microenvironments. Finally, testing this construct in other members of the Proteobacteria demonstrated its broader utility. The results illustrate how a limited ability to predict synthetic promoter-reporter performance can be overcome through iterative screening and reengineering.IMPORTANCE Transcriptional reporters can be powerful tools for assessing when a particular regulator is active; however, native promoters may not be ideal for this purpose. Optimal reporters should be specific to the regulator being examined and should maximize the difference between the "on" and "off" states; however, these properties are distinct from the selective pressures driving the evolution of natural promoters. Synthetic promoters offer a promising alternative, but our understanding often does not enable fully predictive promoter design, and the large number of alternative sequence possibilities can be intractable. In a synthetic promoter region with over 34 billion sequence variants, we identified bases correlated with favorable performance by screening only 83 candidates, allowing us to rationally constrain our design. We thereby generated an optimized reporter that is induced by PhoB and used it to explore the low-phosphate response of V. fischeri This promoter design strategy will facilitate the engineering of other regulator-specific reporters.
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45
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Cal S, Obaya AJ. Imaging Proteolytic Activities in Mouse Models of Cancer. Methods Mol Biol 2018; 1731:247-260. [PMID: 29318559 PMCID: PMC6435259 DOI: 10.1007/978-1-4939-7595-2_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Proteases are "protein-cleaving" enzymes, which, in addition to their non-specific degrading function, also catalyze the highly specific and regulated process of proteolytic processing, thus regulating multiple biological functions. Alterations in proteolytic activity occur during pathological conditions such as cancer. One of the major deregulated classes of proteases in cancer is caspases, the proteolytic initiators and mediators of the apoptotic machinery. The ability to image apoptosis noninvasively in living cells and animal models of cancer can not only provide new insight into the biological basis of the disease but can also be used as a quantitative tool to screen and evaluate novel therapeutic strategies. Optical molecular imaging such as bioluminescence-based genetically engineered biosensors has been developed in our laboratory and exploited to study protease activity in animal models with a high signal to noise. Using the circularly permuted form of firefly luciferase, we have developed a reporter for Caspase 3/7, referred to as Caspase 3/7 GloSensor. Here, we discuss the use of the Caspase 3/7 GloSensor for imaging apoptotic activity in mouse xenografts and genetically engineered mouse models of cancer and present the potential of this powerful platform technology to image the proteolytic activity of numerous other proteases.
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Affiliation(s)
- Santiago Cal
- Instituto Universitario de Oncología (IUOPA), Universidad de Oviedo, Oviedo, Asturias Spain
| | - Alvaro J. Obaya
- Instituto Universitario de Oncología (IUOPA), Universidad de Oviedo, Oviedo, Asturias Spain
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46
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Stahlhut SG, Alqarzaee AA, Jensen C, Fisker NS, Pereira AR, Pinho MG, Thomas VC, Frees D. The ClpXP protease is dispensable for degradation of unfolded proteins in Staphylococcus aureus. Sci Rep 2017; 7:11739. [PMID: 28924169 PMCID: PMC5603545 DOI: 10.1038/s41598-017-12122-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/04/2017] [Indexed: 01/01/2023] Open
Abstract
In living cells intracellular proteolysis is crucial for protein homeostasis, and ClpP proteases are conserved between eubacteria and the organelles of eukaryotic cells. In Staphylococcus aureus, ClpP associates to the substrate specificity factors, ClpX and ClpC forming two ClpP proteases, ClpXP and ClpCP. To address how individual ClpP proteases impact cell physiology, we constructed a S. aureus mutant expressing ClpX with an I265E substitution in the ClpP recognition tripeptide of ClpX. This mutant cannot degrade established ClpXP substrates confirming that the introduced amino acid substitution abolishes ClpXP activity. Phenotypic characterization of this mutant showed that ClpXP activity controls cell size and is required for growth at low temperature. Cells expressing the ClpXI265E variant, in contrast to cells lacking ClpP, are not sensitive to heat-stress and do not accumulate protein aggregates showing that ClpXP is dispensable for degradation of unfolded proteins in S. aureus. Consistent with this finding, transcriptomic profiling revealed strong induction of genes responding to protein folding stress in cells devoid of ClpP, but not in cells lacking only ClpXP. In the latter cells, highly upregulated loci include the urease operon, the pyrimidine biosynthesis operon, the betA-betB operon, and the pathogenicity island, SaPI5, while virulence genes were dramatically down-regulated.
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Affiliation(s)
- Steen G Stahlhut
- Department of Veterinary Disease Biology, University of Copenhagen, 1870, Frederiksberg C, Denmark
| | - Abdulelah A Alqarzaee
- Center for Staphylococcal Research, Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, 68198, USA
| | - Camilla Jensen
- Department of Veterinary Disease Biology, University of Copenhagen, 1870, Frederiksberg C, Denmark
| | - Niclas S Fisker
- Department of Veterinary Disease Biology, University of Copenhagen, 1870, Frederiksberg C, Denmark
| | - Ana R Pereira
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Mariana G Pinho
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Vinai Chittezham Thomas
- Center for Staphylococcal Research, Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, 68198, USA
| | - Dorte Frees
- Department of Veterinary Disease Biology, University of Copenhagen, 1870, Frederiksberg C, Denmark.
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Ortiz C, Casanova M, Palacios P, Vicente M. The hypermorph FtsA* protein has an in vivo role in relieving the Escherichia coli proto-ring block caused by excess ZapC. PLoS One 2017; 12:e0184184. [PMID: 28877250 PMCID: PMC5587298 DOI: 10.1371/journal.pone.0184184] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 08/18/2017] [Indexed: 01/09/2023] Open
Abstract
Assembly of the proto-ring, formed by the essential FtsZ, FtsA and ZipA proteins, and its progression into a divisome, are essential events for Escherichia coli division. ZapC is a cytoplasmic protein that belongs to a group of non-essential components that assist FtsZ during proto-ring assembly. Any overproduction of these proteins leads to faulty FtsZ-rings, resulting in a cell division block. We show that ZapC overproduction can be counteracted by an excess of the ZipA-independent hypermorph FtsA* mutant, but not by similar amounts of wild type FtsA+. An excess of FtsA+ allowed regular spacing of the ZapC-blocked FtsZ-rings, but failed to promote recruitment of the late-assembling proteins FtsQ, FtsK and FtsN and therefore, to activate constriction. In contrast, overproduction of FtsA*, besides allowing correct FtsZ-ring localization at midcell, restored the ability of FtsQ, FtsK and FtsN to be incorporated into active divisomes.
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Affiliation(s)
- Cristina Ortiz
- Centro Nacional de Biotecnología- Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Mercedes Casanova
- Centro Nacional de Biotecnología- Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Pilar Palacios
- Centro Nacional de Biotecnología- Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Miguel Vicente
- Centro Nacional de Biotecnología- Consejo Superior de Investigaciones Científicas, Madrid, Spain
- * E-mail:
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Abrahão J, Mokry DZ, Ramos CHI. Hsp78 (78 kDa Heat Shock Protein), a Representative AAA Family Member Found in the Mitochondrial Matrix of Saccharomyces cerevisiae. Front Mol Biosci 2017; 4:60. [PMID: 28879184 PMCID: PMC5572323 DOI: 10.3389/fmolb.2017.00060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/08/2017] [Indexed: 11/30/2022] Open
Abstract
ATPases associated with diverse cellular activities (AAA+) form a superfamily of proteins involved in a variety of functions and are characterized by the presence of an ATPase module containing two conserved motifs known as Walker A and Walker B. ClpB and Hsp104, chaperones that have disaggregase activities, are members of a subset of this superfamily, known as the AAA family, and are characterized by the presence of a second highly conserved motif, known as the second region of homology (SRH). Hsp104 and its homolog Hsp78 (78 kDa heat shock protein) are representatives of the Clp family in yeast. The structure and function of Hsp78 is reviewed and the possible existence of other homologs in metazoans is discussed.
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Affiliation(s)
| | - David Z Mokry
- Chemistry Institute, University of CampinasCampinas, Brazil
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49
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Duran EC, Weaver CL, Lucius AL. Comparative Analysis of the Structure and Function of AAA+ Motors ClpA, ClpB, and Hsp104: Common Threads and Disparate Functions. Front Mol Biosci 2017; 4:54. [PMID: 28824920 PMCID: PMC5540906 DOI: 10.3389/fmolb.2017.00054] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/13/2017] [Indexed: 11/25/2022] Open
Abstract
Cellular proteostasis involves not only the expression of proteins in response to environmental needs, but also the timely repair or removal of damaged or unneeded proteins. AAA+ motor proteins are critically involved in these pathways. Here, we review the structure and function of AAA+ proteins ClpA, ClpB, and Hsp104. ClpB and Hsp104 rescue damaged proteins from toxic aggregates and do not partner with any protease. ClpA functions as the regulatory component of the ATP dependent protease complex ClpAP, and also remodels inactive RepA dimers into active monomers in the absence of the protease. Because ClpA functions both with and without a proteolytic component, it is an ideal system for developing strategies that address one of the major challenges in the study of protein remodeling machines: how do we observe a reaction in which the substrate protein does not undergo covalent modification? Here, we review experimental designs developed for the examination of polypeptide translocation catalyzed by the AAA+ motors in the absence of proteolytic degradation. We propose that transient state kinetic methods are essential for the examination of elementary kinetic mechanisms of these motor proteins. Furthermore, rigorous kinetic analysis must also account for the thermodynamic properties of these complicated systems that reside in a dynamic equilibrium of oligomeric states, including the biologically active hexamer.
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Affiliation(s)
- Elizabeth C Duran
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
| | - Clarissa L Weaver
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
| | - Aaron L Lucius
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
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Andrianova AG, Kudzhaev AM, Dubovtseva ES, Rotanova TV. Involvement of the N-terminal region and its characteristic coiled-coil fragment in the function and structure maintenance of E. coli LonA protease. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2017. [DOI: 10.1134/s1068162017040021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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