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Yigit K, Chien P. Proteolytic control of FixT by the Lon protease impacts FixLJ signaling in Caulobacter crescentus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.579008. [PMID: 38370668 PMCID: PMC10871180 DOI: 10.1101/2024.02.05.579008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Responding to changes in oxygen levels is critical for aerobic microbes. In Caulobacter crescentus, low oxygen is sensed by the FixL-FixJ two-component system which induces multiple genes, including heme biosynthesis, to accommodate microaerobic conditions. The FixLJ inhibitor FixT is also induced under low oxygen conditions and is degraded by the Lon protease, which together provides negative feedback proposed to adjust FixLJ signaling thresholds during changing conditions. Here, we address if the degradation of FixT by the Lon protease contributes to phenotypic defects associated with loss of Lon. We find that ∆lon strains are deficient in FixLJ-dependent heme biosynthesis, consistent with elevated FixT levels as deletion of fixT suppresses this defect. Transcriptomics validate this result as there is diminished expression of many FixLJ-activated genes in ∆lon. However, no physiological changes in response to microaerobic conditions occurred upon loss of Lon, suggesting that FixT dynamics are not a major contributor to fitness in oxygen limiting conditions. Similarly, stabilization of FixT in ∆lon strains does not contribute to any known Lon-related fitness defect, such as cell morphology defects or stress sensitivity. In fact, cells lacking both FixT and Lon are compromised in viability during adaptation to long term aerobic growth. Our work highlights the complexity of protease-dependent regulation of transcription factors and explains the molecular basis of defective heme accumulation in Lon-deficient Caulobacter.
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Affiliation(s)
- Kubra Yigit
- Department of Biochemistry and Molecular Biology, Molecular and Cellular Biology Program, University of Massachusetts, Amherst Amherst, MA 01003
| | - Peter Chien
- Department of Biochemistry and Molecular Biology, Molecular and Cellular Biology Program, University of Massachusetts, Amherst Amherst, MA 01003
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2
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Karlo J, Dhillon AK, Siddhanta S, Singh SP. Reverse stable isotope labelling with Raman spectroscopy for microbial proteomics. JOURNAL OF BIOPHOTONICS 2024; 17:e202300341. [PMID: 38010366 DOI: 10.1002/jbio.202300341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/26/2023] [Accepted: 11/01/2023] [Indexed: 11/29/2023]
Abstract
Global proteome changes in microbes affect the survival and overall production of commercially relevant metabolites through different bioprocesses. The existing methods to monitor proteome level changes are destructive in nature. Stable isotope probing (SIP) coupled with Raman spectroscopy is a relatively new approach for proteome analysis. However, applying this approach for monitoring changes in a large culture volume is not cost-effective. In this study, for the first time we are presenting a novel method of combining reverse SIP using 13 C-glucose and Deuterium to monitor the proteome changes through Raman spectroscopy. The findings of the study revealed visible changes (blue shifts) in proteome related peaks that can be used for monitoring proteome dynamics, that is, synthesis of nascent amino acids and its turnover with time in a non-destructive, cost-effective, and label-free manner.
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Affiliation(s)
- Jiro Karlo
- Department of Biosciences and Bioengineering, Indian Institute of Technology Dharwad, Dharwad, India
| | | | - Soumik Siddhanta
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi, India
| | - Surya Pratap Singh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Dharwad, Dharwad, India
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3
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Papa R, Imperlini E, Trecca M, Paris I, Vrenna G, Artini M, Selan L. Virulence of Pseudomonas aeruginosa in Cystic Fibrosis: Relationships between Normoxia and Anoxia Lifestyle. Antibiotics (Basel) 2023; 13:1. [PMID: 38275311 PMCID: PMC10812786 DOI: 10.3390/antibiotics13010001] [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: 11/27/2023] [Revised: 12/14/2023] [Accepted: 12/17/2023] [Indexed: 01/27/2024] Open
Abstract
The airways of cystic fibrosis (CF) patients are colonized by many pathogens and the most common is Pseudomonas aeruginosa, an environmental pathogen that is able to infect immunocompromised patients thanks to its ability to develop resistance to conventional antibiotics. Over 12% of all patients colonized by P. aeruginosa harbour multi-drug resistant species. During airway infection in CF, P. aeruginosa adopts various mechanisms to survive in a hostile ecological niche characterized by low oxygen concentration, nutrient limitation and high osmotic pressure. To this end, P. aeruginosa uses a variety of virulence factors including pigment production, biofilm formation, motility and the secretion of toxins and proteases. This study represents the first report that systematically analyzes the differences in virulence features, in normoxia and anoxia, of clinical P. aeruginosa isolated from CF patients, characterized by multi- or pan-drug antibiotic resistance compared to antibiotic sensitive strains. The virulence features, such as biofilm formation, protease secretion and motility, are highly diversified in anaerobiosis, which reflects the condition of chronic CF infection. These findings may contribute to the understanding of the real-world lifestyle of pathogens isolated during disease progression in each particular patient and to assist in the design of therapeutic protocols for personalized medicine.
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Affiliation(s)
- Rosanna Papa
- Department of Public Health and Infectious Diseases, Sapienza University, p. le Aldo Moro 5, 00185 Rome, Italy; (R.P.); (M.T.); (I.P.); (L.S.)
| | - Esther Imperlini
- Department for Innovation in Biological, Agro-Food and Forest Systems, University of Tuscia, 01100 Viterbo, Italy;
| | - Marika Trecca
- Department of Public Health and Infectious Diseases, Sapienza University, p. le Aldo Moro 5, 00185 Rome, Italy; (R.P.); (M.T.); (I.P.); (L.S.)
| | - Irene Paris
- Department of Public Health and Infectious Diseases, Sapienza University, p. le Aldo Moro 5, 00185 Rome, Italy; (R.P.); (M.T.); (I.P.); (L.S.)
| | - Gianluca Vrenna
- Research Unit of Diagnostical and Management Innovations, Children’s Hospital and Institute Research Bambino Gesù, 00165 Rome, Italy;
| | - Marco Artini
- Department of Public Health and Infectious Diseases, Sapienza University, p. le Aldo Moro 5, 00185 Rome, Italy; (R.P.); (M.T.); (I.P.); (L.S.)
| | - Laura Selan
- Department of Public Health and Infectious Diseases, Sapienza University, p. le Aldo Moro 5, 00185 Rome, Italy; (R.P.); (M.T.); (I.P.); (L.S.)
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4
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Detomasi TC, Batka AE, Valastyan JS, Hydorn MA, Craik CS, Bassler BL, Marletta MA. Proteases influence colony aggregation behavior in Vibrio cholerae. J Biol Chem 2023; 299:105386. [PMID: 37898401 PMCID: PMC10709122 DOI: 10.1016/j.jbc.2023.105386] [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: 07/10/2023] [Revised: 10/03/2023] [Accepted: 10/16/2023] [Indexed: 10/30/2023] Open
Abstract
Aggregation behavior provides bacteria protection from harsh environments and threats to survival. Two uncharacterized proteases, LapX and Lap, are important for Vibrio cholerae liquid-based aggregation. Here, we determined that LapX is a serine protease with a preference for cleavage after glutamate and glutamine residues in the P1 position, which processes a physiologically based peptide substrate with a catalytic efficiency of 180 ± 80 M-1s-1. The activity with a LapX substrate identified by a multiplex substrate profiling by mass spectrometry screen was 590 ± 20 M-1s-1. Lap shares high sequence identity with an aminopeptidase (termed VpAP) from Vibrio proteolyticus and contains an inhibitory bacterial prepeptidase C-terminal domain that, when eliminated, increases catalytic efficiency on leucine p-nitroanilide nearly four-fold from 5.4 ± 4.1 × 104 M-1s-1 to 20.3 ± 4.3 × 104 M-1s-1. We demonstrate that LapX processes Lap to its mature form and thus amplifies Lap activity. The increase is approximately eighteen-fold for full-length Lap (95.7 ± 5.6 × 104 M-1s-1) and six-fold for Lap lacking the prepeptidase C-terminal domain (11.3 ± 1.9 × 105 M-1s-1). In addition, substrate profiling reveals preferences for these two proteases that could inform in vivo function. Furthermore, purified LapX and Lap restore the timing of the V. cholerae aggregation program to a mutant lacking the lapX and lap genes. Both proteases must be present to restore WT timing, and thus they appear to act sequentially: LapX acts on Lap, and Lap acts on the substrate involved in aggregation.
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Affiliation(s)
- Tyler C Detomasi
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Allison E Batka
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA
| | - Julie S Valastyan
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA; The Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Molly A Hydorn
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; Department of Microbiology and Immunology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Charles S Craik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA; The Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Michael A Marletta
- Department of Chemistry, University of California, Berkeley, Berkeley, California, USA; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA.
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5
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Akar R, Fink MJ, Omnus DJ, Jonas K. Regulation of the general stress response sigma factor σ T by Lon-mediated proteolysis. J Bacteriol 2023; 205:e0022823. [PMID: 37930077 PMCID: PMC10662116 DOI: 10.1128/jb.00228-23] [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: 07/13/2023] [Accepted: 10/20/2023] [Indexed: 11/07/2023] Open
Abstract
IMPORTANCE Regulated protein degradation is a critical process in all cell types, which contributes to the precise regulation of protein amounts in response to internal and external cues. In bacteria, protein degradation is carried out by ATP-dependent proteases. Although past work revealed detailed insights into the operation principles of these proteases, there is limited knowledge about the substrate proteins that are degraded by distinct proteases and the regulatory role of proteolysis in cellular processes. This study reveals a direct role of the conserved protease Lon in regulating σT, a transcriptional regulator of the general stress response in α-proteobacteria. Our work is significant as it underscores the importance of regulated proteolysis in modulating the levels of key regulatory proteins under changing conditions.
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Affiliation(s)
- Roya Akar
- Science for Life Laboratory and Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius, Stockholm, Sweden
| | - Matthias J. Fink
- Science for Life Laboratory and Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius, Stockholm, Sweden
| | - Deike J. Omnus
- Science for Life Laboratory and Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius, Stockholm, Sweden
| | - Kristina Jonas
- Science for Life Laboratory and Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius, Stockholm, Sweden
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6
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Feng J, Janaína de Campos L, Seleem MA, Conda-Sheridan M. Synthesis and biological evaluation of sulfonylpyridine derivatives as potential anti-chlamydia agents. Bioorg Med Chem 2023; 91:117401. [PMID: 37453189 DOI: 10.1016/j.bmc.2023.117401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/18/2023]
Abstract
Chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection in the United States and the world. This pathogen can cause health problems ranging from trachoma (blindness) to damage of the fallopian tubes or ectopic pregnancy, which can be life-threatening if not treated properly. To this day, there is no chlamydia-specific drug on the market. Previously, we reported the activity and basic structure-activity relationships (SAR) of sulfonylpyridine molecules that possess antichlamydial action. Based on those results, we prepared a new series of derivatives. Our data indicate the new analogs can halt the growth of C. trachomatis. The lead compound, 22, was more active than our previous molecules and did not affect the growth of S. aureus and E. coli, suggesting bacterial selectivity. We performed docking studies on the presumed target, the cylindrical protease of Chlamydia. The in-silico studies partially explained the in vitro biological result as well as predicted a possible binding pose in the binding pocket. The top compound displayed a good cytotoxicity profile towards mammalian cell lines and was stable in both serum and stimulated gastric fluid. The presented data suggests the sulfonylpyridines are promising and selective anti-chlamydial compounds that merit further structural optimization.
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Affiliation(s)
- Jiachen Feng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE 68198-6125, United States
| | - Luana Janaína de Campos
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE 68198-6125, United States
| | - Mohamed A Seleem
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE 68198-6125, United States
| | - Martin Conda-Sheridan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE 68198-6125, United States.
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7
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Wang D, Wang W, Fang L, Qi L, Zhang Y, Liu J, Liang Y, Yang H, Wang M, Wei X, Jiang R, Liu Y, Zhou W, Fang X. Mitochondrial Protease Targeting Chimeras for Mitochondrial Matrix Protein Degradation. J Am Chem Soc 2023. [PMID: 37276358 DOI: 10.1021/jacs.3c03756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Targeted protein degradation (TPD) is an emerging technique for protein regulation. Currently, all TPD developed in eukaryotic cells relies on either ubiquitin-proteasome or lysosomal systems, thus are powerless against target proteins in membrane organelles lacking proteasomes and lysosomes, such as mitochondria. Here, we developed a mitochondrial protease targeting chimera (MtPTAC) to address this issue. MtPTAC is a bifunctional small molecule that can bind to mitochondrial caseinolytic protease P (ClpP) at one end and target protein at the other. Mechanistically, MtPTAC activates the hydrolase activity of ClpP while simultaneously bringing target proteins into proximity with ClpP. Taking mitochondrial RNA polymerase (POLRMT) as a model protein, we have demonstrated the powerful proteolytic ability and antitumor application prospects of MtPTAC, both in vivo and in vitro. This is the first modularly designed TPD that can specifically hydrolyze target proteins inside mitochondria.
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Affiliation(s)
- Dachi Wang
- School of Chemistry and Materials, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Wenxi Wang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
- School of Molecular Medicine, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
| | - Le Fang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Lubin Qi
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Yuchao Zhang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Jie Liu
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Yuxin Liang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Key Laboratory of Molecular Nanostructure and Nanotechnology, Chinese Academy of Science, Beijing 100190, China
| | - Hongwei Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Key Laboratory of Molecular Nanostructure and Nanotechnology, Chinese Academy of Science, Beijing 100190, China
| | - Mengjie Wang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Xiaojian Wei
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Ruibin Jiang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Yuan Liu
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Wei Zhou
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
| | - Xiaohong Fang
- School of Chemistry and Materials, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, PR China
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Key Laboratory of Molecular Nanostructure and Nanotechnology, Chinese Academy of Science, Beijing 100190, China
- School of Molecular Medicine, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
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8
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Study on spoilage potential and its molecular basis of Shewanella putrefaciens in response to cold conditions by Label-free quantitative proteomic analysis. World J Microbiol Biotechnol 2022; 39:40. [PMID: 36512125 DOI: 10.1007/s11274-022-03479-y] [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: 05/31/2022] [Accepted: 11/18/2022] [Indexed: 12/15/2022]
Abstract
To elucidate how Shewanella putrefaciens survives and produces spoilage products in response to cold conditions, the metabolic and protease activity of S. putrefaciens DSM6067 cultured at three different temperatures (30 °C, 10 °C, and 4 °C) was studied by determining the bacterial growth, total volatile basic nitrogen (TVB-N), biogenic amines, extracellular protease activity, as well as the differential expressed proteins via Label-free quantitative proteomics analysis. The lag phase of the strain cultured at 10 °C and 4 °C was about 20 h and 120 h longer than at 30 °C, respectively. The TVB-N increased to 89.23 mg N/100 g within 28 h at 30 °C, and it needed at least 72 h and 224 h at 10 °C and 4 °C, respectively. Cold temperatures (10 °C and 4 °C) also inhibited the yield factors and the extracellular protease activity per cell at the lag phase. However, the protease activity per cell and the yield factors of the sample cultivated at 10 °C and 4 °C well recovered, especially at the mid and latter stages of the log phase. The further quantitative proteomic analysis displayed a complex biological network to tackle cold stress: cold stress responses, nutrient uptake, and energy conservation strategy. It was observed that the protease and peptidase were upregulated, so as to the degradation pathways of serine, arginine, and aspartate, which might lead to the accumulation of spoilage products. This study highlighted the spoilage potential of S. putrefaciens still should be concerned even at low temperatures.
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9
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Structural Studies of Bypass of Forespore Protein C from Bacillus Subtilis to Reveal Its Inhibitory Molecular Mechanism for SpoIVB. Catalysts 2022. [DOI: 10.3390/catal12121530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Activation of pro-σK processing requires a signaling protease SpoIVB that is secreted from the forespore into the space between the two cells during sporulation in Bacillus subtilis. Bypass of forespore protein C (BofC) is an inhibitor preventing the autoproteolysis of SpoIVB, ensuring the factor σK operates regularly at the correct time during the sporulation. However, the regulatory mechanisms of BofC on pro-σK processing are still unclear, especially in the aspect of the interaction between BofC and SpoIVB. Herein, the recombinant BofC (rBofC) was expressed in the periplasm by the E. coli expression system, and crystal growth conditions were obtained and optimized. Further, the crystal structure of rBofC was determined by X-ray crystallography, which is nearly identical to the structures determined by NMR and predicted by AlphaFold. In addition, the modeled structure of the BofC–SpoIVB complex provides insights into the molecular mechanism by which domain 1 of BofC occupies the active site of the SpoIVB serine protease domain, leading to the inhibition of the catalytical activity of SpoIVB and prevention of the substrate of SpoIVB (SpoIVFA) from binding to the active site.
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10
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Ge Z, Yuan P, Chen L, Chen J, Shen D, She Z, Lu Y. New Global Insights on the Regulation of the Biphasic Life Cycle and Virulence Via ClpP-Dependent Proteolysis in Legionella pneumophila. Mol Cell Proteomics 2022; 21:100233. [PMID: 35427813 PMCID: PMC9112007 DOI: 10.1016/j.mcpro.2022.100233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 02/17/2022] [Accepted: 04/07/2022] [Indexed: 01/11/2023] Open
Abstract
Legionella pneumophila, an environmental bacterium that parasitizes protozoa, causes Legionnaires’ disease in humans that is characterized by severe pneumonia. This bacterium adopts a distinct biphasic life cycle consisting of a nonvirulent replicative phase and a virulent transmissive phase in response to different environmental conditions. Hence, the timely and fine-tuned expression of growth and virulence factors in a life cycle–dependent manner is crucial for survival and replication. Here, we report that the completion of the biphasic life cycle and bacterial pathogenesis is greatly dependent on the protein homeostasis regulated by caseinolytic protease P (ClpP)-dependent proteolysis. We characterized the ClpP-dependent dynamic profiles of the regulatory and substrate proteins during the biphasic life cycle of L. pneumophila using proteomic approaches and discovered that ClpP-dependent proteolysis specifically and conditionally degraded the substrate proteins, thereby directly playing a regulatory role or indirectly controlling cellular events via the regulatory proteins. We further observed that ClpP-dependent proteolysis is required to monitor the abundance of fatty acid biosynthesis–related protein Lpg0102/Lpg0361/Lpg0362 and SpoT for the normal regulation of L. pneumophila differentiation. We also found that the control of the biphasic life cycle and bacterial virulence is independent. Furthermore, the ClpP-dependent proteolysis of Dot/Icm (defect in organelle trafficking/intracellular multiplication) type IVB secretion system and effector proteins at a specific phase of the life cycle is essential for bacterial pathogenesis. Therefore, our findings provide novel insights on ClpP-dependent proteolysis, which spans a broad physiological spectrum involving key metabolic pathways that regulate the transition of the biphasic life cycle and bacterial virulence of L. pneumophila, facilitating adaptation to aquatic and intracellular niches. ClpP is the major determinant of biphasic life cycle–dependent protein turnover. ClpP-dependent proteolysis monitors SpoT abundance for cellular differentiation. ClpP-dependent regulation of life cycle and bacterial virulence is independent. ClpP-dependent proteolysis of T4BSS and effector proteins is vital for virulence.
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Affiliation(s)
- Zhenhuang Ge
- School of Chemistry, Sun Yat-sen University, Guangzhou, China; School of Life Sciences, Sun Yat-sen University, Guangzhou, China; Run Ze Laboratory for Gastrointestinal Microbiome Study, Sun Yat-sen University, Guangzhou, China
| | - Peibo Yuan
- Microbiome Medicine Center, Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Lingming Chen
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Junyi Chen
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China; Run Ze Laboratory for Gastrointestinal Microbiome Study, Sun Yat-sen University, Guangzhou, China
| | - Dong Shen
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zhigang She
- School of Chemistry, Sun Yat-sen University, Guangzhou, China
| | - Yongjun Lu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China; Run Ze Laboratory for Gastrointestinal Microbiome Study, Sun Yat-sen University, Guangzhou, China.
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11
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A novel strategy of gene screen based on multi-omics in Streptomyces roseosporus. Appl Microbiol Biotechnol 2022; 106:3103-3112. [PMID: 35389068 DOI: 10.1007/s00253-022-11904-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/27/2022] [Accepted: 03/29/2022] [Indexed: 11/02/2022]
Abstract
Daptomycin is a new lipopeptide antibiotic for treatment of severe infection caused by multi-drug-resistant bacteria, but its production cost remains high currently. Thus, it is very important to improve the fermentation ability of the daptomycin producer Streptomyces roseosporus. Here, we found that the deletion of proteasome in S. roseosporus would result in the loss of ability to produce daptomycin. Therefore, transcriptome and 4D label-free proteome analyses of the proteasome mutant (Δprc) and wild type were carried out, showing 457 differential genes. Further, five genes were screened by integrated crotonylation omics analysis. Among them, two genes (orf04750/orf05959) could significantly promote the daptomycin synthesis by overexpression, and the fermentation yield in shake flask increased by 54% and 76.7%, respectively. By enhancing the crotonylation modification via lysine site mutation (K-Q), the daptomycin production in shake flask was finally increased by 98.8% and 206.3%, respectively. This result proved that the crotonylation modification of appropriate proteins could effectively modulate daptomycin biosynthesis. In summary, we established a novel strategy of gene screen for antibiotic biosynthesis process, which is more convenient than the previous screening method based on pathway-specific regulators. KEY POINTS: • Δprc strain has lost the ability of daptomycin production • Five genes were screened by multi-omics analysis • Two genes (orf04750/orf05959) could promote the daptomycin synthesis by overexpression.
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12
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Sauer RT, Fei X, Bell TA, Baker TA. Structure and function of ClpXP, a AAA+ proteolytic machine powered by probabilistic ATP hydrolysis. Crit Rev Biochem Mol Biol 2022; 57:188-204. [PMID: 34923891 PMCID: PMC9871882 DOI: 10.1080/10409238.2021.1979461] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
ClpXP is an archetypical AAA+ protease, consisting of ClpX and ClpP. ClpX is an ATP-dependent protein unfoldase and polypeptide translocase, whereas ClpP is a self-compartmentalized peptidase. ClpXP is currently the only AAA+ protease for which high-resolution structures exist, the molecular basis of recognition for a protein substrate is understood, extensive biochemical and genetic analysis have been performed, and single-molecule optical trapping has allowed direct visualization of the kinetics of substrate unfolding and translocation. In this review, we discuss our current understanding of ClpXP structure and function, evaluate competing sequential and probabilistic mechanisms of ATP hydrolysis, and highlight open questions for future exploration.
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Affiliation(s)
- Robert T. Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Xue Fei
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Tristan A. Bell
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Tania A. Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
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13
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Yeom J, Park JS, Jeon YM, Song BS, Yoo SM. Synthetic fused sRNA for the simultaneous repression of multiple genes. Appl Microbiol Biotechnol 2022; 106:2517-2527. [PMID: 35291022 DOI: 10.1007/s00253-022-11867-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/03/2022] [Accepted: 03/05/2022] [Indexed: 11/02/2022]
Abstract
Efficient control over multiple gene expression still presents a major challenge. Synthetic sRNA enables targeted gene expression control in trans without directly modifying the chromosome, but its use to simultaneously target multiple genes can often cause cell growth defects because of the need for additional energy for transcription and lowering of their repression efficiency by limiting the amount of Hfq protein. To address these limitations, we present fusion sRNA (fsRNA) that simultaneously regulates the translation of multiple genes efficiently. It is constructed by linking the mRNA-binding modules for multiple targeted genes in one sRNA scaffold via one-pot generation using overlap extension PCR. The repression capacity of fsRNA was demonstrated by the construction of sRNAs to target four endogenous genes: caiF, hybG, ytfR and minD in Escherichia coli. Their cross-reactivity and the effect on cell growth were also investigated. As practical applications, we applied fsRNA to violacein- and protocatechuic acid-producing strains, resulting in increases of 13% violacein and 81% protocatechuic acid, respectively. The developed fsRNA-mediated multiple gene expression regulation system thus enables rapid and efficient development of optimised cell factories for valuable chemicals without cell growth defects and limiting cellular resources.Key points• Synthetic fusion sRNA (fsRNA)-based system was constructed for the repression of multiple target genes.• fsRNA repressed multiple genes by only expressing a single sRNA while minimising the cellular burden.• The application of fsRNA showed the increased production titers of violacein (13%) and protocatechuic acid (81%).
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Affiliation(s)
- Jinho Yeom
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Jong Seong Park
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Yong Min Jeon
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Beom Seop Song
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Seung Min Yoo
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea.
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14
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Ishii Y, Hatta M, Deguchi R, Kawata M, Maruyama S. Gene expression alterations from reversible to irreversible stages during coral metamorphosis. ZOOLOGICAL LETTERS 2022; 8:4. [PMID: 35078542 PMCID: PMC8787945 DOI: 10.1186/s40851-022-00187-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
For corals, metamorphosis from planktonic larvae to sedentary polyps is an important life event, as it determines the environment in which they live for a lifetime. Although previous studies on the reef-building coral Acropora have clarified a critical time point during metamorphosis when cells are committed to their fates, as defined by an inability to revert back to their previous states as swimming larvae (here referred to as the "point of no return"), the molecular mechanisms of this commitment to a fate remain unclear. To address this issue, we analyzed the transcriptomic changes before and after the point of no return by inducing metamorphosis of Acropora tenuis with Hym-248, a metamorphosis-inducing neuropeptide. Gene Ontology and pathway enrichment analysis of the 5893 differentially expressed genes revealed that G protein-coupled receptors (GPCRs) were enriched, including GABA receptor and Frizzled gene subfamilies, which showed characteristic temporal expression patterns. The GPCRs were then classified by comparison with those of Homo sapiens, Nematostella vectensis and Platynereis dumerilii. Classification of the differentially expressed genes into modules based on expression patterns showed that some modules with large fluctuations after the point of no return were biased toward functions such as protein metabolism and transport. This result suggests that in precommitted larvae, different types of GPCR genes function to ensure a proper environment, whereas in committed larvae, intracellular protein transport and proteolysis may cause a loss of the reversibility of metamorphosis as a result of cell differentiation.
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Affiliation(s)
- Yuu Ishii
- Department of Biology, Miyagi University of Education, Aoba-ku, Sendai, Sendai, Miyagi 980-0845 Japan
- Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578 Japan
| | - Masayuki Hatta
- Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo, 112-8610 Japan
| | - Ryusaku Deguchi
- Department of Biology, Miyagi University of Education, Aoba-ku, Sendai, Sendai, Miyagi 980-0845 Japan
| | - Masakado Kawata
- Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578 Japan
| | - Shinichiro Maruyama
- Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi 980-8578 Japan
- Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo, 112-8610 Japan
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15
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Giliazeva AG, Misheeva PS, Sharipova MR, Mardanova AM. Bioinformatic Analysis of a Grimelysin-like Protease in the Klebsiella oxytoca Strain NK-1. BIONANOSCIENCE 2022. [DOI: 10.1007/s12668-021-00924-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Abstract
Bacteria orchestrate collective behaviors using the cell-cell communication process called quorum sensing (QS). QS relies on the synthesis, release, and group-wide detection of small molecules called autoinducers. In Vibrio cholerae, a multicellular community aggregation program occurs in liquid, during the stationary phase, and in the high-cell-density QS state. Here, we demonstrate that this aggregation program consists of two subprograms. In one subprogram, which we call void formation, structures form that contain few cells but provide a scaffold within which cells can embed. The other subprogram relies on flagellar machinery and enables cells to enter voids. A genetic screen for factors contributing to void formation, coupled with companion molecular analyses, showed that four extracellular proteases, Vca0812, Vca0813, HapA, and PrtV, control the onset timing of both void formation and aggregation; moreover, proteolytic activity is required. These proteases, or their downstream products, can be shared between void-producing and non-void-forming cells and can elicit aggregation in a normally nonaggregating V. cholerae strain. Employing multiple proteases to control void formation and aggregation timing could provide a redundant and irreversible path to commitment to this community lifestyle.
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17
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Recent advances in tuning the expression and regulation of genes for constructing microbial cell factories. Biotechnol Adv 2021; 50:107767. [PMID: 33974979 DOI: 10.1016/j.biotechadv.2021.107767] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 12/14/2022]
Abstract
To overcome environmental problems caused by the use of fossil resources, microbial cell factories have become a promising technique for the sustainable and eco-friendly development of valuable products from renewable resources. Constructing microbial cell factories with high titers, yields, and productivity requires a balance between growth and production; to this end, tuning gene expression and regulation is necessary to optimise and precisely control complicated metabolic fluxes. In this article, we review the current trends and advances in tuning gene expression and regulation and consider their engineering at each of the three stages of gene regulation: genomic, mRNA, and protein. In particular, the technological approaches utilised in a diverse range of genetic-engineering-based tools for the construction of microbial cell factories are reviewed and representative applications of these strategies are presented. Finally, the prospects for strategies and systems for tuning gene expression and regulation are discussed.
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Yokoyama T, Niinae T, Tsumagari K, Imami K, Ishihama Y, Hizukuri Y, Akiyama Y. The Escherichia coli S2P intramembrane protease RseP regulates ferric citrate uptake by cleaving the sigma factor regulator FecR. J Biol Chem 2021; 296:100673. [PMID: 33865858 PMCID: PMC8144685 DOI: 10.1016/j.jbc.2021.100673] [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: 02/04/2021] [Revised: 04/08/2021] [Accepted: 04/14/2021] [Indexed: 02/03/2023] Open
Abstract
Escherichia coli RseP, a member of the site-2 protease family of intramembrane proteases, is involved in the activation of the σE extracytoplasmic stress response and elimination of signal peptides from the cytoplasmic membrane. However, whether RseP has additional cellular functions is unclear. In this study, we used mass spectrometry-based quantitative proteomic analysis to search for new substrates that might reveal unknown physiological roles for RseP. Our data showed that the levels of several Fec system proteins encoded by the fecABCDE operon (fec operon) were significantly decreased in an RseP-deficient strain. The Fec system is responsible for the uptake of ferric citrate, and the transcription of the fec operon is controlled by FecI, an alternative sigma factor, and its regulator FecR, a single-pass transmembrane protein. Assays with a fec operon expression reporter demonstrated that the proteolytic activity of RseP is essential for the ferric citrate-dependent upregulation of the fec operon. Analysis using the FecR protein and FecR-derived model proteins showed that FecR undergoes sequential processing at the membrane and that RseP participates in the last step of this sequential processing to generate the N-terminal cytoplasmic fragment of FecR that participates in the transcription of the fec operon with FecI. A shortened FecR construct was not dependent on RseP for activation, confirming this cleavage step is the essential and sufficient role of RseP. Our study unveiled that E. coli RseP performs the intramembrane proteolysis of FecR, a novel physiological role that is essential for regulating iron uptake by the ferric citrate transport system.
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Affiliation(s)
- Tatsuhiko Yokoyama
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Tomoya Niinae
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Kazuya Tsumagari
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Koshi Imami
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Yasushi Ishihama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Yohei Hizukuri
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.
| | - Yoshinori Akiyama
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.
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Yeom J, Groisman EA. Reduced ATP-dependent proteolysis of functional proteins during nutrient limitation speeds the return of microbes to a growth state. Sci Signal 2021; 14:14/667/eabc4235. [PMID: 33500334 DOI: 10.1126/scisignal.abc4235] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
When cells run out of nutrients, the growth rate greatly decreases. Here, we report that microorganisms, such as the bacterium Salmonella enterica serovar Typhimurium, speed up the return to a rapid growth state by preventing the proteolysis of functional proteins by ATP-dependent proteases while in the slow-growth state or stationary phase. This reduction in functional protein degradation resulted from a decrease in the intracellular concentration of ATP that was nonetheless sufficient to allow the continued degradation of nonfunctional proteins by the same proteases. Protein preservation occurred under limiting magnesium, carbon, or nitrogen conditions, indicating that this response was not specific to low availability of a particular nutrient. Nevertheless, the return to rapid growth required proteins that mediate responses to the specific nutrient limitation conditions, because the transcriptional regulator PhoP was necessary for rapid recovery only after magnesium starvation. Reductions in intracellular ATP and in ATP-dependent proteolysis also enabled the yeast Saccharomyces cerevisiae to recover faster from stationary phase. Our findings suggest that protein preservation during a slow-growth state is a conserved microbial strategy that facilitates the return to a growth state once nutrients become available.
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Affiliation(s)
- Jinki Yeom
- Department of Microbial Pathogenesis, Yale School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA.,Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857, Singapore.,Department of Microbiology and Immunology, College of Medicine, Seoul National University, Seoul 03080, Korea.,Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Korea
| | - Eduardo A Groisman
- Department of Microbial Pathogenesis, Yale School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA. .,Yale Microbial Sciences Institute, P.O. Box 27389, West Haven, CT 06516, USA
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20
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Yan Z, He F, Xiao F, He H, Li D, Cong L, Lin L, Zhu H, Wu Y, Yan R, Li X, Shan H. A semi-tryptic peptide centric metaproteomic mining approach and its potential utility in capturing signatures of gut microbial proteolysis. MICROBIOME 2021; 9:12. [PMID: 33436102 PMCID: PMC7805185 DOI: 10.1186/s40168-020-00967-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/06/2020] [Indexed: 05/05/2023]
Abstract
BACKGROUND Proteolysis regulation allows gut microbes to respond rapidly to dynamic intestinal environments by fast degradation of misfolded proteins and activation of regulatory proteins. However, alterations of gut microbial proteolytic signatures under complex disease status such as inflammatory bowel disease (IBD, including Crohn's disease (CD) and ulcerative colitis (UC)), have not been investigated. Metaproteomics holds the potential to investigate gut microbial proteolysis because semi-tryptic peptides mainly derive from endogenous proteolysis. RESULTS We have developed a semi-tryptic peptide centric metaproteomic mining approach to obtain a snapshot of human gut microbial proteolysis signatures. This approach employed a comprehensive meta-database, two-step multiengine database search, and datasets with high-resolution fragmentation spectra to increase the confidence of semi-tryptic peptide identification. The approach was validated by discovering altered proteolysis signatures of Escherichia coli heat shock response. Utilizing two published large-scale metaproteomics datasets containing 623 metaproteomes from 447 fecal and 176 mucosal luminal interface (MLI) samples from IBD patients and healthy individuals, we obtain potential signatures of altered gut microbial proteolysis at taxonomic, functional, and cleavage site motif levels. The functional alterations mainly involved microbial carbohydrate transport and metabolism, oxidative stress, cell motility, protein synthesis, and maturation. Altered microbial proteolysis signatures of CD and UC mainly occurred in terminal ileum and descending colon, respectively. Microbial proteolysis patterns exhibited low correlations with β-diversity and moderate correlations with microbial protease and chaperones levels, respectively. Human protease inhibitors and immunoglobulins were mainly negatively associated with microbial proteolysis patterns, probably because of the inhibitory effects of these host factors on gut microbial proteolysis events. CONCLUSIONS This semi-tryptic peptide centric mining strategy offers a label-free approach to discover signatures of in vivo gut microbial proteolysis events if experimental conditions are well controlled. It can also capture in vitro proteolysis signatures to facilitate the evaluation and optimization of experimental conditions. Our findings highlight the complex and diverse proteolytic events of gut microbiome, providing a unique layer of information beyond taxonomic and proteomic abundance. Video abstract.
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Affiliation(s)
- Zhixiang Yan
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China.
| | - Feixiang He
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Fei Xiao
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Huanhuan He
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Dan Li
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Li Cong
- Department of Endocrinology and Metabolism, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Lu Lin
- Department of Gastroenterology, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Huijin Zhu
- Department of Gastroenterology, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Yanyan Wu
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China
| | - Ru Yan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macao, China.
| | - Xiaofeng Li
- Department of Gastroenterology, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China.
| | - Hong Shan
- Guangdong Provincial Key Laboratory of Biomedical Imaging and Guangdong Provincial Engineering Research Center of Molecular Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China.
- Center for Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, 519000, Guangdong Province, China.
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21
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Wettstadt S, Llamas MA. Role of Regulated Proteolysis in the Communication of Bacteria With the Environment. Front Mol Biosci 2020; 7:586497. [PMID: 33195433 PMCID: PMC7593790 DOI: 10.3389/fmolb.2020.586497] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 09/22/2020] [Indexed: 12/29/2022] Open
Abstract
For bacteria to flourish in different niches, they need to sense signals from the environment and translate these into appropriate responses. Most bacterial signal transduction systems involve proteins that trigger the required response through the modification of gene transcription. These proteins are often produced in an inactive state that prevents their interaction with the RNA polymerase and/or the DNA in the absence of the inducing signal. Among other mechanisms, regulated proteolysis is becoming increasingly recognized as a key process in the modulation of the activity of these signal response proteins. Regulated proteolysis can either produce complete degradation or specific cleavage of the target protein, thus modifying its function. Because proteolysis is a fast process, the modulation of signaling proteins activity by this process allows for an immediate response to a given signal, which facilitates adaptation to the surrounding environment and bacterial survival. Moreover, regulated proteolysis is a fundamental process for the transmission of extracellular signals to the cytosol through the bacterial membranes. By a proteolytic mechanism known as regulated intramembrane proteolysis (RIP) transmembrane proteins are cleaved within the plane of the membrane to liberate a cytosolic domain or protein able to modify gene transcription. This allows the transmission of a signal present on one side of a membrane to the other side where the response is elicited. In this work, we review the role of regulated proteolysis in the bacterial communication with the environment through the modulation of the main bacterial signal transduction systems, namely one- and two-component systems, and alternative σ factors.
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Affiliation(s)
- Sarah Wettstadt
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - María A Llamas
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
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22
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Schwarz SR, Hirsch S, Hiergeist A, Kirschneck C, Muehler D, Hiller KA, Maisch T, Al-Ahmad A, Gessner A, Buchalla W, Cieplik F. Limited antimicrobial efficacy of oral care antiseptics in microcosm biofilms and phenotypic adaptation of bacteria upon repeated exposure. Clin Oral Investig 2020; 25:2939-2950. [PMID: 33033920 PMCID: PMC8060176 DOI: 10.1007/s00784-020-03613-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 10/01/2020] [Indexed: 02/06/2023]
Abstract
Objectives The aims of this study were to investigate the antimicrobial efficacy of antiseptics in saliva-derived microcosm biofilms, and to examine phenotypic adaption of bacteria upon repeated exposure to sub-inhibitory antiseptic concentrations. Methods Saliva-derived biofilms were formed mimicking caries- or gingivitis-associated conditions, respectively. Microbial compositions were analyzed by semiconductor-based 16S rRNA sequencing. Biofilms were treated with CHX, CPC, BAC, ALX, and DQC for 1 or 10 min, and colony forming units (CFU) were evaluated. Phenotypic adaptation of six selected bacterial reference strains toward CHX, CPC, and BAC was assessed by measuring minimum inhibitory concentrations (MICs) over 10 passages of sub-inhibitory exposure. Protein expression profiles were investigated by SDS-PAGE. Results Both biofilms showed outgrowth of streptococci and Veillonella spp., while gingivitis biofilms also showed increased relative abundances of Actinomyces, Granulicatella, and Gemella spp. Antiseptic treatment for 1 min led to no relevant CFU-reductions despite for CPC. When treated for 10 min, CPC was most effective followed by BAC, ALX, CHX, and DQC. Stable adaptations with up to fourfold MIC increases were found in E. coli toward all tested antiseptics, in E. faecalis toward CHX and BAC, and in S. aureus toward CPC. Adapted E. coli strains showed different protein expression as compared with the wildtype strain. Conclusion Antiseptics showed limited antimicrobial efficacy toward mature biofilms when applied for clinically relevant treatment periods. Bacteria showed phenotypic adaptation upon repeated sub-inhibitory exposure. Clinical relevance Clinicians should be aware that wide-spread use of antiseptics may pose the risk of inducing resistances in oral bacteria.
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Affiliation(s)
- Sophia R Schwarz
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Stefanie Hirsch
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Andreas Hiergeist
- Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
| | | | - Denise Muehler
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Karl-Anton Hiller
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Tim Maisch
- Department of Dermatology, University Hospital Regensburg, Regensburg, Germany
| | - Ali Al-Ahmad
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - André Gessner
- Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
| | - Wolfgang Buchalla
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Fabian Cieplik
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
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Li G, Obeng E, Shu J, Shu J, Chen J, Wu Y, He Y. Genomic Variability and Post-translational Protein Processing Enhance the Immune Evasion of Mycoplasma hyopneumoniae and Its Interaction With the Porcine Immune System. Front Immunol 2020; 11:510943. [PMID: 33117335 PMCID: PMC7575705 DOI: 10.3389/fimmu.2020.510943] [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: 11/14/2019] [Accepted: 08/27/2020] [Indexed: 11/23/2022] Open
Abstract
Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) is a geographically widespread and economically devastating pathogen that colonizes ciliated epithelium; the infection of Mhp can damnify the mucociliary functions as well as leading to Mycoplasma pneumonia of swine (MPS). MPS is a chronic respiratory infectious disease with high infectivity, and the mortality can be increased by secondary infections as the host immunity gets down-regulated during Mhp infection. The host immune responses are regarded as the main driving force for the disease development, while MPS is prone to attack repeatedly in farms even with vaccination or other treatments. As one of the smallest microorganisms with limited genome scale and metabolic pathways, Mhp can use several mechanisms to achieve immune evasion effect and derive enough nutrients from its host, indicating that there is a strong interaction between Mhp and porcine organism. In this review, we summarized the immune evasion mechanisms from genomic variability and post-translational protein processing. Besides, Mhp can induce the immune cells apoptosis by reactive oxygen species production, excessive nitric oxide (NO) release and caspase activation, and stimulate the release of cytokines to regulate inflammation. This article seeks to provide some new points to reveal the complicated interaction between the pathogen and host immune system with Mhp as a typical example, further providing some new strategies for the vaccine development against Mhp infection.
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Affiliation(s)
- Gaojian Li
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Enoch Obeng
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Jinqi Shu
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Jianhong Shu
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China.,Zhejiang Hom-Sun Biosciences Co., Ltd., Shaoxing, China
| | - Jian Chen
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yuehong Wu
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yulong He
- Department of Biopharmacy, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
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24
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Comerlato CB, Ritter AC, Miyamoto KN, Brandelli A. Proteomic study of Enterococcus durans LAB18S growing on prebiotic oligosaccharides. Food Microbiol 2020; 89:103430. [DOI: 10.1016/j.fm.2020.103430] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 01/09/2020] [Accepted: 01/11/2020] [Indexed: 02/07/2023]
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25
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Parrell D, Kroos L. Channels modestly impact compartment-specific ATP levels during Bacillus subtilis sporulation and a rise in the mother cell ATP level is not necessary for Pro-σ K cleavage. Mol Microbiol 2020; 114:563-581. [PMID: 32515031 DOI: 10.1111/mmi.14560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 01/13/2023]
Abstract
Starvation of Bacillus subtilis initiates endosporulation involving formation of mother cell (MC) and forespore (FS) compartments. During engulfment, the MC membrane migrates around the FS and protein channels connect the two compartments. The channels are necessary for postengulfment FS gene expression, which relieves inhibition of SpoIVFB, an intramembrane protease that cleaves Pro-σK , releasing σK into the MC. SpoIVFB has an ATP-binding domain exposed to the MC cytoplasm, but the role of ATP in regulating Pro-σK cleavage has been unclear, as has the impact of the channels on MC and FS ATP levels. Using luciferase produced separately in each compartment to measure relative ATP concentrations during sporulation, we found that the MC ATP concentration rises about twofold coincident with increasing cleavage of Pro-σK , and the FS ATP concentration does not decline. Mutants lacking a channel protein or defective in channel protein turnover exhibited modest and varied effects on ATP levels, which suggested that low ATP concentration does not explain the lack of postengulfment FS gene expression in channel mutants. Furthermore, a rise in the MC ATP level was not necessary for Pro-σK cleavage by SpoIVFB, based on analysis of mutants that bypass the need for relief of SpoIVFB inhibition.
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Affiliation(s)
- Daniel Parrell
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Lee Kroos
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
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26
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Minasov G, Lam MR, Rosas-Lemus M, Sławek J, Woinska M, Shabalin IG, Shuvalova L, Palsson BØ, Godzik A, Minor W, Satchell KJF. Comparison of metal-bound and unbound structures of aminopeptidase B proteins from Escherichia coli and Yersinia pestis. Protein Sci 2020; 29:1618-1628. [PMID: 32306515 DOI: 10.1002/pro.3876] [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: 02/09/2020] [Revised: 04/14/2020] [Accepted: 04/14/2020] [Indexed: 11/06/2022]
Abstract
Protein degradation by aminopeptidases is involved in bacterial responses to stress. Escherichia coli produces two metal-dependent M17 family leucine aminopeptidases (LAPs), aminopeptidase A (PepA) and aminopeptidase B (PepB). Several structures have been solved for PepA as well as other bacterial M17 peptidases. Herein, we report the first structures of a PepB M17 peptidase. The E. coli PepB protein structure was determined at a resolution of 2.05 and 2.6 Å. One structure has both Zn2+ and Mn2+ , while the second structure has two Zn2+ ions bound to the active site. A 2.75 Å apo structure is also reported for PepB from Yersinia pestis. Both proteins form homohexamers, similar to the overall arrangement of PepA and other M17 peptidases. However, the divergent N-terminal domain in PepB is much larger resulting in a tertiary structure that is more expanded. Modeling of a dipeptide substrate into the C-terminal LAP domain reveals contacts that account for PepB to uniquely cleave after aspartate.
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Affiliation(s)
- George Minasov
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Matthew R Lam
- Department of Molecular Biosciences, Weinberg School of Arts and Sciences, Northwestern University, Evanston, Illinois, USA
| | - Monica Rosas-Lemus
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Joanna Sławek
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Magdalena Woinska
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ivan G Shabalin
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ludmilla Shuvalova
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Bernhard Ø Palsson
- Department of Bioengineering and Pediatrics, University of California, San Diego, California, USA
| | - Adam Godzik
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Biomedical Sciences, University of California, Riverside School of Medicine, Riverside, California, USA
| | - Wladek Minor
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
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27
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Huang M, Zhao Y, Feng L, Zhu L, Zhan L, Chen X. Role of the ClpX from Corynebacterium crenatum involved in stress responses and energy metabolism. Appl Microbiol Biotechnol 2020; 104:5505-5517. [PMID: 32300856 DOI: 10.1007/s00253-020-10597-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 03/24/2020] [Accepted: 03/31/2020] [Indexed: 02/04/2023]
Abstract
ClpX and ClpP are involved in many important functions, including stress responses and energy metabolism, in microorganisms. However, the ClpX and ClpP of microbes used in industrial scale have rarely been studied. Industrial bacterial fermentation experiences a variety of stresses, and energy metabolism is extremely important for industrial bacteria. Thus, the role played by the ClpX and ClpP of industrial bacteria in fermentation should be investigated. Most microorganisms have a single clpP gene, while Corynebacterium crenatum AS 1.542 possesses two clpPs. Herein, the clpX, clpP1, and clpP2 of C. crenatum were cloned, and its fusion protein was expressed and characterized. We also constructed clpX deletion mutant and complementation strain. Results indicate that ClpX serves an important function in thermal, pH, and ethanol stresses. It is also involved in NADPH synthesis and glucose consumption during fermentation.
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Affiliation(s)
- Mingzhu Huang
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China.,School of Life Science, Key Laboratory of Functional Small Organic Molecule of Ministry of Education, Jiangxi Normal University, 99 Ziyang Road, Nanchang, 330096, People's Republic of China
| | - Yue Zhao
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China
| | - Lin Feng
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China
| | - Lingfeng Zhu
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China
| | - Li Zhan
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China
| | - Xuelan Chen
- Department of Life Science, Jiangxi Normal University, Nanchang, 330096, People's Republic of China. .,School of Life Science, Key Laboratory of Functional Small Organic Molecule of Ministry of Education, Jiangxi Normal University, 99 Ziyang Road, Nanchang, 330096, People's Republic of China.
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28
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Seleem MA, Rodrigues de Almeida N, Chhonker YS, Murry DJ, Guterres ZDR, Blocker AM, Kuwabara S, Fisher DJ, Leal ES, Martinefski MR, Bollini M, Monge ME, Ouellette SP, Conda-Sheridan M. Synthesis and Antichlamydial Activity of Molecules Based on Dysregulators of Cylindrical Proteases. J Med Chem 2020; 63:4370-4387. [PMID: 32227948 DOI: 10.1021/acs.jmedchem.0c00371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Chlamydia trachomatis is the most common sexually transmitted bacterial disease globally and the leading cause of infertility and preventable infectious blindness (trachoma) in the world. Unfortunately, there is no FDA-approved treatment specific for chlamydial infections. We recently reported two sulfonylpyridines that halt the growth of the pathogen. Herein, we present a SAR of the sulfonylpyridine molecule by introducing substituents on the aromatic regions. Biological evaluation studies showed that several analogues can impair the growth of C. trachomatis without affecting host cell viability. The compounds did not kill other bacteria, indicating selectivity for Chlamydia. The compounds presented mild toxicity toward mammalian cell lines. The compounds were found to be nonmutagenic in a Drosophila melanogaster assay and exhibited a promising stability in both plasma and gastric fluid. The presented results indicate this scaffold is a promising starting point for the development of selective antichlamydial drugs.
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Affiliation(s)
- Mohamed A Seleem
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Nathalia Rodrigues de Almeida
- Department of Chemistry, College of Arts and Sciences, University of Nebraska at Omaha, Omaha, Nebraska 68182, United States
| | - Yashpal Singh Chhonker
- Clinical Pharmacology Laboratory, Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Daryl J Murry
- Clinical Pharmacology Laboratory, Department of Pharmacy Practice and Science, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Zaira da Rosa Guterres
- Laboratory of Cytogenetics and Mutagenesis, State University of Mato Grosso do Sul, Mundo Novo, Matto Grasso do Sul, Brazil
| | - Amanda M Blocker
- School of Biological Sciences, Southern Illinois University Carbondale, Carbondale, Illinois 62901, United States
| | - Shiomi Kuwabara
- School of Biological Sciences, Southern Illinois University Carbondale, Carbondale, Illinois 62901, United States
| | - Derek J Fisher
- School of Biological Sciences, Southern Illinois University Carbondale, Carbondale, Illinois 62901, United States
| | - Emilse S Leal
- Centro de Investigaciones en BioNanociencias (CIBION), Consejo Nacional de Investigaciones Cientı́ficas y Técnicas (CONICET), Godoy Cruz, 2390 Ciudad de Buenos Aires, Argentina
| | - Manuela R Martinefski
- Centro de Investigaciones en BioNanociencias (CIBION), Consejo Nacional de Investigaciones Cientı́ficas y Técnicas (CONICET), Godoy Cruz, 2390 Ciudad de Buenos Aires, Argentina
| | - Mariela Bollini
- Centro de Investigaciones en BioNanociencias (CIBION), Consejo Nacional de Investigaciones Cientı́ficas y Técnicas (CONICET), Godoy Cruz, 2390 Ciudad de Buenos Aires, Argentina
| | - María Eugenia Monge
- Centro de Investigaciones en BioNanociencias (CIBION), Consejo Nacional de Investigaciones Cientı́ficas y Técnicas (CONICET), Godoy Cruz, 2390 Ciudad de Buenos Aires, Argentina
| | - Scot P Ouellette
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Martin Conda-Sheridan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
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29
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Arenas J, Bossers-de Vries R, Harders-Westerveen J, Buys H, Ruuls-van Stalle LMF, Stockhofe-Zurwieden N, Zaccaria E, Tommassen J, Wells JM, Smith HE, de Greeff A. In vivo transcriptomes of Streptococcus suis reveal genes required for niche-specific adaptation and pathogenesis. Virulence 2020; 10:334-351. [PMID: 30957693 PMCID: PMC6527017 DOI: 10.1080/21505594.2019.1599669] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Streptococcus suis is a Gram-positive bacterium and a zoonotic pathogen residing in the nasopharynx or the gastrointestinal tract of pigs with a potential of causing life-threatening invasive disease. It is endemic in the porcine production industry worldwide, and it is also an emerging human pathogen. After invasion, the pathogen adapts to cause bacteremia and disseminates to different organs including the brain. To gain insights in this process, we infected piglets with a highly virulent strain of S. suis, and bacterial transcriptomes were obtained from blood and different organs (brain, joints, and heart) when animals had severe clinical symptoms of infection. Microarrays were used to determine the genome-wide transcriptional profile at different infection sites and during growth in standard growth medium in vitro. We observed differential expression of around 30% of the Open Reading Frames (ORFs) and infection-site specific patterns of gene expression. Genes with major changes in expression were involved in transcriptional regulation, metabolism, nutrient acquisition, stress defenses, and virulence, amongst others, and results were confirmed for a subset of selected genes using RT-qPCR. Mutants were generated in two selected genes, and the encoded proteins, i.e., NADH oxidase and MetQ, were shown to be important virulence factors in coinfection experiments and in vitro assays. The knowledge derived from this study regarding S. suis gene expression in vivo and identification of virulence factors is important for the development of novel diagnostic and therapeutic strategies to control S. suis disease.
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Affiliation(s)
- Jesús Arenas
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
| | - Ruth Bossers-de Vries
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
| | - José Harders-Westerveen
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
| | - Herma Buys
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
| | | | | | - Edoardo Zaccaria
- b Host Microbe Interactions , Wageningen UR , Wageningen , The Netherlands
| | - Jan Tommassen
- c Department of Molecular Microbiology and Institute of Biomembranes , Utrecht University , Utrecht , The Netherlands
| | - Jerry M Wells
- b Host Microbe Interactions , Wageningen UR , Wageningen , The Netherlands
| | - Hilde E Smith
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
| | - Astrid de Greeff
- a Department of Infection Biology , Wageningen BioVeterinary Research (WBVR) , Lelystad , The Netherlands
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30
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Ramos-Silva P, Serrano M, Henriques AO. From Root to Tips: Sporulation Evolution and Specialization in Bacillus subtilis and the Intestinal Pathogen Clostridioides difficile. Mol Biol Evol 2020; 36:2714-2736. [PMID: 31350897 PMCID: PMC6878958 DOI: 10.1093/molbev/msz175] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Bacteria of the Firmicutes phylum are able to enter a developmental pathway that culminates with the formation of highly resistant, dormant endospores. Endospores allow environmental persistence, dissemination and for pathogens, are also infection vehicles. In both the model Bacillus subtilis, an aerobic organism, and in the intestinal pathogen Clostridioides difficile, an obligate anaerobe, sporulation mobilizes hundreds of genes. Their expression is coordinated between the forespore and the mother cell, the two cells that participate in the process, and is kept in close register with the course of morphogenesis. The evolutionary mechanisms by which sporulation emerged and evolved in these two species, and more broadly across Firmicutes, remain largely unknown. Here, we trace the origin and evolution of sporulation using the genes known to be involved in the process in B. subtilis and C. difficile, and estimating their gain-loss dynamics in a comprehensive bacterial macroevolutionary framework. We show that sporulation evolution was driven by two major gene gain events, the first at the base of the Firmicutes and the second at the base of the B. subtilis group and within the Peptostreptococcaceae family, which includes C. difficile. We also show that early and late sporulation regulons have been coevolving and that sporulation genes entail greater innovation in B. subtilis with many Bacilli lineage-restricted genes. In contrast, C. difficile more often recruits new sporulation genes by horizontal gene transfer, which reflects both its highly mobile genome, the complexity of the gut microbiota, and an adjustment of sporulation to the gut ecosystem.
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Affiliation(s)
- Paula Ramos-Silva
- Instituto Gulbenkian de Ciência, Oeiras, Portugal.,Marine Biodiversity Group, Naturalis Biodiversity Center, Leiden, The Netherlands
| | - Mónica Serrano
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Adriano O Henriques
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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31
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Dutoit R, Van Gompel T, Brandt N, Van Elder D, Van Dyck J, Sobott F, Droogmans L. How metal cofactors drive dimer-dodecamer transition of the M42 aminopeptidase TmPep1050 of Thermotoga maritima. J Biol Chem 2019; 294:17777-17789. [PMID: 31611236 DOI: 10.1074/jbc.ra119.009281] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 09/24/2019] [Indexed: 11/06/2022] Open
Abstract
The M42 aminopeptidases are dinuclear aminopeptidases displaying a peculiar tetrahedron-shaped structure with 12 subunits. Their quaternary structure results from the self-assembly of six dimers controlled by their divalent metal ion cofactors. The oligomeric-state transition remains debated despite the structural characterization of several archaeal M42 aminopeptidases. The main bottleneck is the lack of dimer structures, hindering the understanding of structural changes occurring during the oligomerization process. We present the first dimer structure of an M42 aminopeptidase, TmPep1050 of Thermotoga maritima, along with the dodecamer structure. The comparison of both structures has allowed us to describe how the metal ion cofactors modulate the active-site fold and, subsequently, affect the interaction interface between dimers. A mutational study shows that the M1 site strictly controls dodecamer formation. The dodecamer structure of TmPep1050 also reveals that a part of the dimerization domain delimits the catalytic pocket and could participate in substrate binding.
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Affiliation(s)
- Raphaël Dutoit
- Laboratory of Microbiology, Department of Molecular Biology, Université Libre de Bruxelles, rue des Professeurs Jeener et Brachet 12, B6041 Charleroi, Belgium .,Labiris Institut de Recherche, avenue Emile Gryzon 1, B1070 Brussels, Belgium
| | - Tom Van Gompel
- Biomolecular and Analytical Mass Spectrometry, Department of Chemistry, Universiteit van Antwerpen, Groenenborgerlaan 171, B2020 Antwerpen, Belgium
| | - Nathalie Brandt
- Labiris Institut de Recherche, avenue Emile Gryzon 1, B1070 Brussels, Belgium
| | - Dany Van Elder
- Laboratory of Microbiology, Department of Molecular Biology, Université Libre de Bruxelles, rue des Professeurs Jeener et Brachet 12, B6041 Charleroi, Belgium
| | - Jeroen Van Dyck
- Biomolecular and Analytical Mass Spectrometry, Department of Chemistry, Universiteit van Antwerpen, Groenenborgerlaan 171, B2020 Antwerpen, Belgium
| | - Frank Sobott
- Biomolecular and Analytical Mass Spectrometry, Department of Chemistry, Universiteit van Antwerpen, Groenenborgerlaan 171, B2020 Antwerpen, Belgium.,Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - Louis Droogmans
- Laboratory of Microbiology, Department of Molecular Biology, Université Libre de Bruxelles, rue des Professeurs Jeener et Brachet 12, B6041 Charleroi, Belgium
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32
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Xie X, Guo N, Xue G, Xie D, Yuan C, Harrison J, Li J, Jiang L, Huang M. Solution Structure of SpoIVB Reveals Mechanism of PDZ Domain-Regulated Protease Activity. Front Microbiol 2019; 10:1232. [PMID: 31244791 PMCID: PMC6581720 DOI: 10.3389/fmicb.2019.01232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 05/17/2019] [Indexed: 01/27/2023] Open
Abstract
Intramembrane proteases hydrolyze peptide bonds within the cell membrane as the decision-making step of various signaling pathways. Sporulation factor IV B protease (SpoIVB) and C-terminal processing proteases B (CtpB) play central roles in cellular differentiation via regulated intramembrane proteolysis (RIP) process which activates pro-σK processing at the σK checkpoint during spore formation. SpoIVB joins CtpB in belonging to the widespread family of PDZ-proteases, but much remains unclear about the molecular mechanisms and structure of SpoIVB. In this study, we expressed inactive SpoIVB (SpoIVBS378A) fused with maltose binding protein (MBP)-tag and obtained the solution structure of SpoIVBS378A from its small angle X-ray scattering (SAXS) data. The fusion protein is more soluble, stable, and yields higher expression compared to SpoIVB without the tag. MBP-tag not only facilitates modeling of the structure in the SAXS envelope but also evaluates reliability of the model. The solution structure of SpoIVBS378A fits closely with the experimental scattering data (χ2= 1.76). Comparing the conformations of PDZ-proteases indicates that SpoIVB adopts a PDZ-protease pattern similar to the high temperature requirement A proteases (HtrAs) rather than CtpB. We not only propose that SpoIVB uses a more direct and simple way to cleave the substrates than that of CtpB, but also that they work together as signal amplifiers to activate downstream proteins in the RIP pathway.
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Affiliation(s)
- Xie Xie
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Nannan Guo
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Guangpu Xue
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Daoqing Xie
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Cai Yuan
- College of Biological Science and Engineering, Fuzhou University, Fuzhou, China
| | - Joshua Harrison
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Jinyu Li
- College of Chemistry, Fuzhou University, Fuzhou, China
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33
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Inniss NL, Prehna G, Morrison DA. The pneumococcal σ X activator, ComW, is a DNA-binding protein critical for natural transformation. J Biol Chem 2019; 294:11101-11118. [PMID: 31160340 DOI: 10.1074/jbc.ra119.007571] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/19/2019] [Indexed: 11/06/2022] Open
Abstract
Natural genetic transformation via horizontal gene transfer enables rapid adaptation to dynamic environments and contributes to both antibiotic resistance and vaccine evasion among bacterial populations. In Streptococcus pneumoniae (pneumococcus), transformation occurs when cells enter competence, a transient state in which cells express the competence master regulator, SigX (σΧ), an alternative σ factor (σ), and a competence co-regulator, ComW. Together, ComW and σX facilitate expression of the genes required for DNA uptake and genetic recombination. SigX activity depends on ComW, as ΔcomW cells transcribe late genes and transform at levels 10- and 10,000-fold below that of WT cells, respectively. Previous findings suggest that ComW functions during assembly of the RNA polymerase-σX holoenzyme to help promote transcription from σX-targeted promoters. However, it remains unknown how ComW facilitates holoenzyme assembly. As ComW seems to be unique to Gram-positive cocci and has no sequence similarity with known transcriptional activators, here we used Rosetta to generate an ab initio model of pneumococcal ComW's 3D-structure. Using this model as a basis for further biochemical, biophysical, and genetic investigations into the molecular features important for its function, we report that ComW is a predicted globular protein and that it interacts with DNA, independently of DNA sequence. We also identified conserved motifs in ComW and show that key residues in these motifs contribute to DNA binding. Lastly, we provide evidence that ComW's DNA-binding activity is important for transformation in pneumococcus. Our findings begin to fill the gaps in understanding how ComW regulates σΧ activity during bacterial natural transformation.
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Affiliation(s)
- Nicole L Inniss
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607
| | - Gerd Prehna
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Donald A Morrison
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607
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34
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Abstract
Regulated proteolysis is a vital process that affects all living things. Bacteria use energy-dependent AAA+ proteases to power degradation of misfolded and native regulatory proteins. Given that proteolysis is an irreversible event, specificity and selectivity in degrading substrates are key. Specificity is often augmented through the use of adaptors that modify the inherent specificity of the proteolytic machinery. Regulated protein degradation is intricately linked to quality control, cell-cycle progression, and physiological transitions. In this review, we highlight recent work that has shed light on our understanding of regulated proteolysis in bacteria. We discuss the role AAA+ proteases play during balanced growth as well as how these proteases are deployed during changes in growth. We present examples of how protease selectivity can be controlled in increasingly complex ways. Finally, we describe how coupling a core recognition determinant to one or more modifying agents is a general theme for regulated protein degradation.
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Affiliation(s)
- Samar A Mahmoud
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA; ,
| | - Peter Chien
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA; ,
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35
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Proteomic approach and expression analysis revealed the differential expression of predicted leptospiral proteases capable of ECM degradation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:712-721. [DOI: 10.1016/j.bbapap.2018.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/22/2018] [Accepted: 04/10/2018] [Indexed: 12/22/2022]
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36
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Stochastic system identification without an a priori chosen kinetic model-exploring feasible cell regulation with piecewise linear functions. NPJ Syst Biol Appl 2018; 4:15. [PMID: 29675268 PMCID: PMC5895840 DOI: 10.1038/s41540-018-0049-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 02/01/2018] [Accepted: 02/03/2018] [Indexed: 12/03/2022] Open
Abstract
Kinetic models are at the heart of system identification. A priori chosen rate functions may, however, be unfitting or too restrictive for complex or previously unanticipated regulation. We applied general purpose piecewise linear functions for stochastic system identification in one dimension using published flow cytometry data on E.coli and report on identification results for equilibrium state and dynamic time series. In metabolic labelling experiments during yeast osmotic stress response, we find mRNA production and degradation to be strongly co-regulated. In addition, mRNA degradation appears overall uncorrelated with mRNA level. Comparison of different system identification approaches using semi-empirical synthetic data revealed the superiority of single-cell tracking for parameter identification. Generally, we find that even within restrictive error bounds for deviation from experimental data, the number of viable regulation types may be large. Indeed, distinct regulation can lead to similar expression behaviour over time. Our results demonstrate that molecule production and degradation rates may often differ from classical constant, linear or Michaelis–Menten type kinetics. Classical cell-regulation models are often imperfectly fitting or even inconsistent with experimental data suggesting inappropriate model assumptions. Martin Hoffmann from Fraunhofer ITEM Regensburg and Jörg Galle from IZBI Leipzig analysed different protein and gene expression data using general purpose piecewise linear functions for system identification. They assessed data corresponding to various experimental techniques for their potential to determine the parameters of their models. Single-cell recordings of expression values over time were most effective for parameter identification. Generally, different and often non-classical cell-regulation models were consistent with the experimental data, even for restrictive error bounds. The authors used virtual treatment experiments to demonstrate that precise knowledge of cell regulation is important for assessing therapy effects. Their findings clearly argue in favour of system identification being performed without an a priori chosen kinetic model.
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37
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Lindemann C, Thomanek N, Kuhlmann K, Meyer HE, Marcus K, Narberhaus F. Next-Generation Trapping of Protease Substrates by Label-Free Proteomics. Methods Mol Biol 2018; 1841:189-206. [PMID: 30259488 DOI: 10.1007/978-1-4939-8695-8_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
AAA+ proteases (ATPases associated with various cellular activities) shape the cellular protein pool in response to environmental conditions. A prerequisite for understanding the underlying recognition and degradation principles is the identification of as many protease substrates as possible. Most previous studies made use of inactive protease variants to trap substrates, which were identified by 2D-gel based proteomics. Since this method is known for limitations in the identification of low-abundant proteins or proteins with many transmembrane domains, we established a trapping approach that overcomes these limitations. We used a proteolytically inactive FtsH variant (FtsHtrap) of Escherichia coli (E. coli) that is still able to bind and translocate substrates into the proteolytic chamber but no longer able to degrade proteins. Proteins associated with FtsHtrap or FtsHwt (proteolytically active FtsH) were purified, concentrated by an 1D-short gel, and identified by LC-coupled mass spectrometry (LC-MS) followed by label-free quantification. The identification of four known FtsH substrates validated this approach and suggests that it is generally applicable to AAA+ proteases.
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Affiliation(s)
- Claudia Lindemann
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - Nikolas Thomanek
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - Katja Kuhlmann
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - Helmut E Meyer
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - Katrin Marcus
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - Franz Narberhaus
- Lehrstuhl für Biologie der Mikroorganismen, Ruhr-Universität Bochum, Bochum, Germany.
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38
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Vorob’eva LI, Rogozhin EA, Khodzhaev EY, Volodyashkin RA, Samoilenko VA. Characterization and stress-protective action of Saccharomyces cerevisiae extracellular peptide factors on propionic acid bacteria. Microbiology (Reading) 2017. [DOI: 10.1134/s0026261717060157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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39
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Miller JM, Chaudhary H, Marsee JD. Phylogenetic analysis predicts structural divergence for proteobacterial ClpC proteins. J Struct Biol 2017; 201:52-62. [PMID: 29129755 DOI: 10.1016/j.jsb.2017.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/06/2017] [Accepted: 11/08/2017] [Indexed: 12/29/2022]
Abstract
Regulated proteolysis is required in all organisms for the removal of misfolded or degradation-tagged protein substrates in cellular quality control pathways. The molecular machines that catalyze this process are known as ATP-dependent proteases with examples that include ClpAP and ClpCP. Clp/Hsp100 subunits form ring-structures that couple the energy of ATP binding and hydrolysis to protein unfolding and subsequent translocation of denatured protein into the compartmentalized ClpP protease for degradation. Copies of the clpA, clpC, clpE, clpK, and clpL genes are present in all characterized bacteria and their gene products are highly conserved in structure and function. However, the evolutionary relationship between these proteins remains unclear. Here we report a comprehensive phylogenetic analysis that suggests divergent evolution yielded ClpA from an ancestral ClpC protein and that ClpE/ClpL represent intermediates between ClpA/ClpC. This analysis also identifies a group of proteobacterial ClpC proteins that are likely not functional in regulated proteolysis. Our results strongly suggest that bacterial ClpC proteins should not be assumed to all function identically due to the structural differences identified here.
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Affiliation(s)
- Justin M Miller
- Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, United States.
| | - Hamza Chaudhary
- Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, United States
| | - Justin D Marsee
- Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, United States
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40
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Berry IJ, Jarocki VM, Tacchi JL, Raymond BBA, Widjaja M, Padula MP, Djordjevic SP. N-terminomics identifies widespread endoproteolysis and novel methionine excision in a genome-reduced bacterial pathogen. Sci Rep 2017; 7:11063. [PMID: 28894154 PMCID: PMC5593965 DOI: 10.1038/s41598-017-11296-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/21/2017] [Indexed: 12/12/2022] Open
Abstract
Proteolytic processing alters protein function. Here we present the first systems-wide analysis of endoproteolysis in the genome-reduced pathogen Mycoplasma hyopneumoniae. 669 N-terminal peptides from 164 proteins were identified, demonstrating that functionally diverse proteins are processed, more than half of which 75 (53%) were accessible on the cell surface. Multiple cleavage sites were characterised, but cleavage with arginine in P1 predominated. Putative functions for a subset of cleaved fragments were assigned by affinity chromatography using heparin, actin, plasminogen and fibronectin as bait. Binding affinity was correlated with the number of cleavages in a protein, indicating that novel binding motifs are exposed, and protein disorder increases, after a cleavage event. Glyceraldehyde 3-phosphate dehydrogenase was used as a model protein to demonstrate this. We define the rules governing methionine excision, show that several aminopeptidases are involved, and propose that through processing, genome-reduced organisms can expand protein function.
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Affiliation(s)
- Iain J Berry
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Veronica M Jarocki
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Jessica L Tacchi
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Benjamin B A Raymond
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Michael Widjaja
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Matthew P Padula
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Steven P Djordjevic
- The ithree institute, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia. .,Proteomics Core Facility, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.
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41
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Two Isoforms of Clp Peptidase in Pseudomonas aeruginosa Control Distinct Aspects of Cellular Physiology. J Bacteriol 2017; 199:JB.00568-16. [PMID: 27849175 DOI: 10.1128/jb.00568-16] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/20/2016] [Indexed: 02/07/2023] Open
Abstract
Caseinolytic peptidases (ClpPs) regulate diverse aspects of cellular physiology in bacteria. Some species have multiple ClpPs, including the opportunistic pathogen Pseudomonas aeruginosa, in which there is an archetypical isoform, ClpP1, and a second isoform, ClpP2, about which little is known. Here, we use phenotypic assays to investigate the biological roles of ClpP1 and ClpP2 and biochemical assays to characterize purified ClpP1, ClpP2, ClpX, and ClpA. Interestingly, ClpP1 and ClpP2 have distinct intracellular roles for motility, pigment production, iron scavenging, and biofilm formation. Of particular interest, ClpP2, but not ClpP1, is required for microcolony organization, where multicellular organized structures first form on the pathway to biofilm production. We found that purified ClpP1 with ClpX or ClpA was enzymatically active, yet to our surprise, ClpP2 was inactive and not fully assembled in vitro; attempts to assist ClpP2 assembly and activation by mixing with the other Clp components failed to turn on ClpP2, as did solution conditions that have helped activate other ClpPs in vitro We postulate that the active form of ClpP2 has yet to be discovered, and we present several potential models to explain its activation as well as the unique role ClpP2 plays in the development of the clinically important biofilms in P. aeruginosaIMPORTANCEPseudomonas aeruginosa is responsible for severe infections of immunocompromised patients. Our work demonstrates that two different isoforms of the Clp peptidase, ClpP1 and ClpP2, control distinct aspects of cellular physiology for this organism. In particular, we identify ClpP2 as being necessary for microcolony organization. Pure active forms of ClpP1 and either ClpX or ClpA were characterized as assembled and active, and ClpP2 was incompletely assembled and inactive. By establishing both the unique biological roles of ClpP1 and ClpP2 and their initial biochemical assemblies, we have set the stage for important future work on the structure, function, and biological targets of Clp proteolytic enzymes in this important opportunistic pathogen.
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Strain-Dependent Recognition of a Unique Degradation Motif by ClpXP in Streptococcus mutans. mSphere 2016; 1:mSphere00287-16. [PMID: 27981232 PMCID: PMC5143411 DOI: 10.1128/msphere.00287-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 11/09/2016] [Indexed: 01/02/2023] Open
Abstract
Regulated proteolysis in bacteria is an important biological process that maintains protein homeostasis. ClpXP, an intracellular proteolytic complex, is the primary protease that is responsible for protein turnover. While the substrates for ClpXP were identified in Escherichia coli, the substrates for vast majority of bacteria are currently unknown. In this study, we identified a unique substrate for ClpXP-mediated degradation in Streptococcus mutans, a dental pathogen. We also found that a small motif composed of 3 amino acids is sufficient for ClpXP-mediated degradation. Identification of this motif will clearly help us to understand the pathogenesis of this organism and other related pathogens. Streptococcus mutans, a dental pathogen, has a remarkable ability to cope with environmental stresses. Under stress conditions, cytoplasmic proteases play a major role in controlling the stability of regulatory proteins and preventing accumulation of damaged and misfolded proteins. ClpXP, a well-conserved cytoplasmic proteolytic system, is crucial in maintaining cellular homeostasis in bacteria. ClpX is primarily responsible for recognition of substrates and subsequent translocation of unfolded substrates into the ClpP proteolytic compartment for degradation. In Escherichia coli, ClpX recognizes distinct motifs present at the C-terminal end of target proteins. However, recognition sequences for ClpXP in other bacteria, including S. mutans, are not known. In this study, using two-dimensional (2D) polyacrylamide gel electrophoresis (PAGE) analysis, we have identified several putative substrates for S. mutans ClpXP. SsbA, which encodes a small DNA binding protein, is one such substrate that is degraded by ClpXP. By sequential deletions, we found that the last 3 C-terminal amino acids, LPF, are sufficient for ClpXP-mediated degradation. Addition of LPF at the C-terminal end of green fluorescent protein (GFP) rendered the protein completely degradable by ClpXP. Alterations of this tripeptide motif impeded ClpXP-mediated degradation. However, recognition of LPF by ClpXP is highly specific to some S. mutans strains (UA159, UA130, and N3209) since not all S. mutans strains recognize the motif. We speculate that an adaptor protein is involved in either substrate recognition or substrate degradation by ClpXP. Nevertheless, this is the first report of a unique recognition sequence for ClpXP in streptococci. IMPORTANCE Regulated proteolysis in bacteria is an important biological process that maintains protein homeostasis. ClpXP, an intracellular proteolytic complex, is the primary protease that is responsible for protein turnover. While the substrates for ClpXP were identified in Escherichia coli, the substrates for vast majority of bacteria are currently unknown. In this study, we identified a unique substrate for ClpXP-mediated degradation in Streptococcus mutans, a dental pathogen. We also found that a small motif composed of 3 amino acids is sufficient for ClpXP-mediated degradation. Identification of this motif will clearly help us to understand the pathogenesis of this organism and other related pathogens.
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43
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Zhang Y, Halder S, Kerr RA, Parrell D, Ruotolo B, Kroos L. Complex Formed between Intramembrane Metalloprotease SpoIVFB and Its Substrate, Pro-σK. J Biol Chem 2016; 291:10347-62. [PMID: 26953342 DOI: 10.1074/jbc.m116.715508] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Indexed: 11/06/2022] Open
Abstract
Intramembrane metalloproteases (IMMPs) are conserved from bacteria to humans and control many important signaling pathways, but little is known about how IMMPs interact with their substrates. SpoIVFB is an IMMP that cleaves Pro-σ(K) during Bacillus subtilis endospore formation. When catalytically inactive SpoIVFB was coexpressed with C-terminally truncated Pro-σ(K)(1-126) (which can be cleaved by active SpoIVFB) in Escherichia coli, the substrate dramatically improved solubilization of the enzyme from membranes with mild detergents. Both the Pro(1-20) and σ(K)(21-126) parts contributed to improving SpoIVFB solubilization from membranes, but only the σ(K) part was needed to form a stable complex with SpoIVFB in a pulldown assay. The last 10 residues of SpoIVFB were required for improved solubilization from membranes by Pro-σ(K)(1-126) and for normal interaction with the substrate. The inactive SpoIVFB·Pro-σ(K)(1-126)-His6 complex was stable during affinity purification and gel filtration chromatography. Disulfide cross-linking of the purified complex indicated that it resembled the complex formed in vivo Ion mobility-mass spectrometry analysis resulted in an observed mass consistent with a 4:2 SpoIVFB·Pro-σ(K)(1-126)-His6 complex. Stepwise photobleaching of SpoIVFB fused to a fluorescent protein supported the notion that the enzyme is tetrameric during B. subtilis sporulation. The results provide the first evidence that an IMMP acts as a tetramer, give new insights into how SpoIVFB interacts with its substrate, and lay the foundation for further biochemical analysis of the enzyme·substrate complex and future structural studies.
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Affiliation(s)
- Yang Zhang
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 and
| | - Sabyasachi Halder
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 and
| | - Richard A Kerr
- the Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Daniel Parrell
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 and
| | - Brandon Ruotolo
- the Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Lee Kroos
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 and
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44
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Joshi KK, Bergé M, Radhakrishnan SK, Viollier PH, Chien P. An Adaptor Hierarchy Regulates Proteolysis during a Bacterial Cell Cycle. Cell 2016; 163:419-31. [PMID: 26451486 DOI: 10.1016/j.cell.2015.09.030] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 07/01/2015] [Accepted: 09/02/2015] [Indexed: 11/30/2022]
Abstract
Regulated protein degradation is essential. The timed destruction of crucial proteins by the ClpXP protease drives cell-cycle progression in the bacterium Caulobacter crescentus. Although ClpXP is active alone, additional factors are inexplicably required for cell-cycle-dependent proteolysis. Here, we show that these factors constitute an adaptor hierarchy wherein different substrates are destroyed based on the degree of adaptor assembly. The hierarchy builds upon priming of ClpXP by the adaptor CpdR, which promotes degradation of one class of substrates and also recruits the adaptor RcdA to degrade a second class of substrates. Adding the PopA adaptor promotes destruction of a third class of substrates and inhibits degradation of the second class. We dissect RcdA to generate bespoke adaptors, identifying critical substrate elements needed for RcdA recognition and uncovering additional cell-cycle-dependent ClpXP substrates. Our work reveals how hierarchical adaptors and primed proteases orchestrate regulated proteolysis during bacterial cell-cycle progression.
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Affiliation(s)
- Kamal Kishore Joshi
- Department of Biochemistry and Molecular Biology, Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Matthieu Bergé
- Department of Microbiology and Molecular Medicine, Institute of Genetics & Genomics in Geneva (iGE3), University of Geneva Medical School, Geneva CH-1211, Switzerland
| | - Sunish Kumar Radhakrishnan
- Department of Microbiology and Molecular Medicine, Institute of Genetics & Genomics in Geneva (iGE3), University of Geneva Medical School, Geneva CH-1211, Switzerland
| | - Patrick Henri Viollier
- Department of Microbiology and Molecular Medicine, Institute of Genetics & Genomics in Geneva (iGE3), University of Geneva Medical School, Geneva CH-1211, Switzerland
| | - Peter Chien
- Department of Biochemistry and Molecular Biology, Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA.
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45
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Chang CY, Hu HT, Tsai CH, Wu WF. The degradation of RcsA by ClpYQ(HslUV) protease in Escherichia coli. Microbiol Res 2016; 184:42-50. [PMID: 26856452 DOI: 10.1016/j.micres.2016.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 12/21/2015] [Accepted: 01/09/2016] [Indexed: 01/30/2023]
Abstract
In Escherichia coli, RcsA, a positive activator for transcription of cps (capsular polysaccharide synthesis) genes, is degraded by the Lon protease. In lon mutant, the accumulation of RcsA leads to overexpression of capsular polysaccharide. In a previous study, overproduction of ClpYQ(HslUV) protease represses the expression of cpsB∷lacZ, but there has been no direct observation demonstrating that ClpYQ degrades RcsA. By means of a MBP-RcsA fusion protein, we showed that RcsA activated cpsB∷lacZ expression and could be rapidly degraded by Lon protease in SG22622 (lon(+)). Subsequently, the comparative half-life experiments performed in the bacterial strains SG22623 (lon) and AC3112 (lon clpY clpQ) indicated that the RcsA turnover rate in AC3112 was relatively slow and RcsA was stable at 30°C or 41°C. In addition, ClpY could interact with RscA in an in vitro pull-down assay, and the more rapid degradation of RcsA was observed in the presence of ClpYQ protease at 41°C. Thus, we conclude that RcsA is indeed proteolized by ClpYQ protease.
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Affiliation(s)
- Chun-Yang Chang
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Hui-Ting Hu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Chih-Hsuan Tsai
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC
| | - Whei-Fen Wu
- Department of Agricultural Chemistry, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan, ROC.
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46
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Olivares AO, Baker TA, Sauer RT. Mechanistic insights into bacterial AAA+ proteases and protein-remodelling machines. Nat Rev Microbiol 2015; 14:33-44. [PMID: 26639779 DOI: 10.1038/nrmicro.2015.4] [Citation(s) in RCA: 203] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To maintain protein homeostasis, AAA+ proteolytic machines degrade damaged and unneeded proteins in bacteria, archaea and eukaryotes. This process involves the ATP-dependent unfolding of a target protein and its subsequent translocation into a self-compartmentalized proteolytic chamber. Related AAA+ enzymes also disaggregate and remodel proteins. Recent structural and biochemical studies, in combination with direct visualization of unfolding and translocation in single-molecule experiments, have illuminated the molecular mechanisms behind these processes and suggest how remodelling of macromolecular complexes by AAA+ enzymes could occur without global denaturation. In this Review, we discuss the structural and mechanistic features of AAA+ proteases and remodelling machines, focusing on the bacterial ClpXP and ClpX as paradigms. We also consider the potential of these enzymes as antibacterial targets and outline future challenges for the field.
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Affiliation(s)
- Adrian O Olivares
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Tania A Baker
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Robert T Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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47
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Palmer SR, Burne RA. Post-transcriptional regulation by distal Shine-Dalgarno sequences in the grpE-dnaK intergenic region of Streptococcus mutans. Mol Microbiol 2015; 98:302-17. [PMID: 26172310 DOI: 10.1111/mmi.13122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2015] [Indexed: 12/24/2022]
Abstract
A unique 373 bp region (igr66) between grpE and dnaK of Streptococcus mutans lacks a promoter but is required for optimal production of DnaK. Northern blotting using probes specific to hrcA, igr66 or dnaK revealed multiple transcripts produced from the dnaK operon and 5'-RACE mapped 5' termini of multiple dnaK transcripts within igr66. One product mapped to a predicted 5'-SL (stem-loop) and two others mapped just 5' to Shine-Dalgarno (SD)-like sequences located immediately upstream to dnaK and to a predicted SL 120 bp upstream of the dnaK start codon (3'-SL). A collection of cat reporter-gene strains containing mutant derivatives of igr66 were engineered. Chloramphenicol acetyltransferase (CAT) activity varied greatly between strains, but there were no correlative changes in cat mRNA levels. Interestingly, mutations introduced into the SD-like sequences 5' to the 3'-SL resulted in an 83-98% decrease in CAT activity. Markerless point mutations introduced upstream of dnaK in the SD-like sequences impaired growth at elevated temperatures and resulted in up to a 40% decrease in DnaK protein after heat shock. Collectively, these results indicate processing within igr66 enhances translation in a temperature dependent manner via non-canonical ribosome binding sites positioned >120 bp upstream of dnaK.
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Affiliation(s)
- Sara R Palmer
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA
| | - Robert A Burne
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA
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Sturm A, Dworkin J. Phenotypic Diversity as a Mechanism to Exit Cellular Dormancy. Curr Biol 2015; 25:2272-7. [PMID: 26279233 DOI: 10.1016/j.cub.2015.07.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 07/03/2015] [Accepted: 07/07/2015] [Indexed: 11/19/2022]
Abstract
Microorganisms can facilitate their survival in stressful environments by entering a state of metabolic inactivity or dormancy. However, this state impairs the function of the very sensory systems necessary to detect favorable growth conditions. Thus, how can a metabolically quiescent cell accurately monitor environmental conditions in order to best decide when to exit dormancy? One strategy employed by microbes to deal with changing environments is the generation of phenotypes that may be less well adapted to a current condition but might confer an advantage in the future. This bet-hedging depends on phenotypic diversity in the population, which itself can derive from naturally occurring stochastic differences in gene expression. In the case of metabolic dormancy, a bet-hedging strategy that has been proposed is the "scout model" where cells comprising a fraction of the dormant population reinitiate growth stochastically, independent of environmental cues. Here, we provide experimental evidence that such a mechanism exists in dormant spores produced by the ubiquitous soil bacterium Bacillus subtilis. We observe that these spores reinitiate growth at a low but measureable frequency even in the absence of an inducing signal. This phenomenon is the result of phenotypic variation in the propensity of individual spores to reinitiate growth spontaneously. Since this bet-hedging mechanism produces individuals that will either grow under favorable conditions or die under unfavorable conditions, a population can properly respond to environmental changes despite the impaired sensory ability of individual cells.
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Affiliation(s)
- Alexander Sturm
- Department of Microbiology & Immunology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Jonathan Dworkin
- Department of Microbiology & Immunology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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49
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Abfalter CM, Schmidt TP, Wessler S. Proteolytic Activities Expressed by Gastrointestinal Pathogens Bacillus cereus, Listeria monocytogenes and Enterococcus faecium in Different Growth Phases. ACTA ACUST UNITED AC 2015; 7:62-70. [PMID: 26682199 PMCID: PMC4678583 DOI: 10.9734/bmrj/2015/16402] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Aims Bacterial proteases are implicated in protein quality control, biofilm formation or might have a direct function in pathogenesis by processing virulence factors or cleaving host factors. In recent years, knowledge of proteases expressed by Gram-negative pathogens remarkably increased. However, investigation of proteases from Gram-positive bacteria is rather rare, but required for the analysis of pathogenesis-relevant proteases. In this study, we extracted and detected proteases from the gastrointestinal pathogens Bacillus cereus, Listeria monocytogenes, and Enterococcus faecium in different growth phases. Methodology Bacteria were grown to logarithmic or stationary phases, harvested and extracted by sonication and French press. For the detection of active proteases, zymography analyses were performed using casein and gelatin as substrates to monitor caseinolytic and gelatinolytic activities. Results We observed different active proteases with different intensities in bacteria grown to logarithmic or stationary phases. Strong activities as gelatinases were detected in B. cereus and distinct caseinolytic proteases exhibiting molecular weights of > 170 kDa, 70 kDa and 45 kDa were shown in L. monocytogenes and E. faecium, respectively. Interestingly, detected proteases were differentially regulated in bacteria grown to logarithmic or stationary phases. Conclusion In summary, the data clearly indicated proteases that are differentially regulated in the Gram-positive pathogens B. cereus, L. monocytogenes, and E. faecium, which might contribute to bacterial pathogenesis.
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Affiliation(s)
- Carmen M Abfalter
- Division of Molecular Biology, Department of Microbiology, Paris-Lodron University, Salzburg, Austria
| | - Thomas P Schmidt
- Division of Molecular Biology, Department of Microbiology, Paris-Lodron University, Salzburg, Austria
| | - Silja Wessler
- Division of Molecular Biology, Department of Microbiology, Paris-Lodron University, Salzburg, Austria
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50
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Bastiaansen KC, Otero-Asman JR, Luirink J, Bitter W, Llamas MA. Processing of cell-surface signalling anti-sigma factors prior to signal recognition is a conserved autoproteolytic mechanism that produces two functional domains. Environ Microbiol 2015; 17:3263-77. [PMID: 25581349 DOI: 10.1111/1462-2920.12776] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 12/19/2014] [Accepted: 01/06/2015] [Indexed: 02/02/2023]
Abstract
Cell-surface signalling (CSS) enables Gram-negative bacteria to transduce an environmental signal into a cytosolic response. This regulatory cascade involves an outer membrane receptor that transmits the signal to an anti-sigma factor in the cytoplasmic membrane, allowing the activation of an extracytoplasmic function (ECF) sigma factor. Recent studies have demonstrated that RseP-mediated proteolysis of the anti-sigma factors is key to σ(ECF) activation. Using the Pseudomonas aeruginosa FoxR anti-sigma factor, we show here that RseP is responsible for the generation of an N-terminal tail that likely contains pro-sigma activity. Furthermore, it has been reported previously that this anti-sigma factor is processed in two separate domains prior to signal recognition. Here, we demonstrate that this process is common in these types of proteins and that the processing event is probably due to autoproteolytic activity. The resulting domains interact and function together to transduce the CSS signal. However, our results also indicate that this processing event is not essential for activity. In fact, we have identified functional CSS anti-sigma factors that are not cleaved prior to signal perception. Together, our results indicate that CSS regulation can occur through both complete and initially processed anti-sigma factors.
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Affiliation(s)
- Karlijn C Bastiaansen
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain.,Section of Molecular Microbiology, Department of Molecular Cell Biology, VU University, Amsterdam, The Netherlands
| | - Joaquín R Otero-Asman
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Joen Luirink
- Section of Molecular Microbiology, Department of Molecular Cell Biology, VU University, Amsterdam, The Netherlands
| | - Wilbert Bitter
- Section of Molecular Microbiology, Department of Molecular Cell Biology, VU University, Amsterdam, The Netherlands
| | - María A Llamas
- Department of Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
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