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The Pup-Proteasome System Protects Mycobacteria from Antimicrobial Antifolates. Antimicrob Agents Chemother 2021; 65:AAC.01967-20. [PMID: 33468462 DOI: 10.1128/aac.01967-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 12/30/2020] [Indexed: 12/21/2022] Open
Abstract
Protein turnover via the Pup-proteasome system (PPS) is essential for nitric oxide resistance and virulence of Mycobacterium tuberculosis, the causative agent of tuberculosis. Our study revealed components of PPS as novel determinants of intrinsic antifolate resistance in both M. tuberculosis and nonpathogenic M. smegmatis The lack of expression of the prokaryotic ubiquitin-like protein (Pup) or the ligase, PafA, responsible for ligating Pup to its protein targets, enhanced antifolate susceptibility in M. smegmatis Cross-species expression of M. tuberculosis homologs restored wild-type resistance to M. smegmatis proteasomal mutants. Targeted deletion of prcA and prcB, encoding the structural components of the PPS proteolytic core, similarly resulted in reduced antifolate resistance. Furthermore, sulfonamides were synergistic with acidified nitrite, and the synergy against mycobacteria was enhanced in the absence of proteasomal activity. In M. tuberculosis, targeted mutagenesis followed by genetic complementation of mpa, encoding the regulatory subunit responsible for translocating pupylated proteins to the proteolytic core, demonstrated a similar function of PPS in antifolate resistance. The overexpression of dihydrofolate reductase, responsible for the reduction of dihydrofolate to tetrahydrofolate, or disruption of the Lonely Guy gene, responsible for PPS-controlled production of cytokinins, abolished PPS-mediated antifolate sensitivity. Together, our results show that PPS protects mycobacteria from antimicrobial antifolates via regulating both folate reduction and cytokinin production.
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2
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Martín JF, Liras P, Sánchez S. Modulation of Gene Expression in Actinobacteria by Translational Modification of Transcriptional Factors and Secondary Metabolite Biosynthetic Enzymes. Front Microbiol 2021; 12:630694. [PMID: 33796086 PMCID: PMC8007912 DOI: 10.3389/fmicb.2021.630694] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/04/2021] [Indexed: 12/20/2022] Open
Abstract
Different types of post-translational modifications are present in bacteria that play essential roles in bacterial metabolism modulation. Nevertheless, limited information is available on these types of modifications in actinobacteria, particularly on their effects on secondary metabolite biosynthesis. Recently, phosphorylation, acetylation, or phosphopantetheneylation of transcriptional factors and key enzymes involved in secondary metabolite biosynthesis have been reported. There are two types of phosphorylations involved in the control of transcriptional factors: (1) phosphorylation of sensor kinases and transfer of the phosphate group to the receiver domain of response regulators, which alters the expression of regulator target genes. (2) Phosphorylation systems involving promiscuous serine/threonine/tyrosine kinases that modify proteins at several amino acid residues, e.g., the phosphorylation of the global nitrogen regulator GlnR. Another post-translational modification is the acetylation at the epsilon amino group of lysine residues. The protein acetylation/deacetylation controls the activity of many short and long-chain acyl-CoA synthetases, transcriptional factors, key proteins of bacterial metabolism, and enzymes for the biosynthesis of non-ribosomal peptides, desferrioxamine, streptomycin, or phosphinic acid-derived antibiotics. Acetyltransferases catalyze acetylation reactions showing different specificity for the acyl-CoA donor. Although it functions as acetyltransferase, there are examples of malonylation, crotonylation, succinylation, or in a few cases acylation activities using bulky acyl-CoA derivatives. Substrates activation by nucleoside triphosphates is one of the central reactions inhibited by lysine acetyltransferases. Phosphorylation/dephosphorylation or acylation/deacylation reactions on global regulators like PhoP, GlnR, AfsR, and the carbon catabolite regulator glucokinase strongly affects the expression of genes controlled by these regulators. Finally, a different type of post-translational protein modification is the phosphopantetheinylation, catalized by phosphopantetheinyl transferases (PPTases). This reaction is essential to modify those enzymes requiring phosphopantetheine groups like non-ribosomal peptide synthetases, polyketide synthases, and fatty acid synthases. Up to five PPTases are present in S. tsukubaensis and S. avermitilis. Different PPTases modify substrate proteins in the PCP or ACP domains of tacrolimus biosynthetic enzymes. Directed mutations of genes encoding enzymes involved in the post-translational modification is a promising tool to enhance the production of bioactive metabolites.
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Affiliation(s)
- Juan F Martín
- Área de Microbiología, Departamento de Biología Molecular, Universidad de León, León, Spain
| | - Paloma Liras
- Área de Microbiología, Departamento de Biología Molecular, Universidad de León, León, Spain
| | - Sergio Sánchez
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, Mexico
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3
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Auliah FN, Nilamyani AN, Shoombuatong W, Alam MA, Hasan MM, Kurata H. PUP-Fuse: Prediction of Protein Pupylation Sites by Integrating Multiple Sequence Representations. Int J Mol Sci 2021; 22:ijms22042120. [PMID: 33672741 PMCID: PMC7924619 DOI: 10.3390/ijms22042120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/12/2021] [Accepted: 02/18/2021] [Indexed: 12/30/2022] Open
Abstract
Pupylation is a type of reversible post-translational modification of proteins, which plays a key role in the cellular function of microbial organisms. Several proteomics methods have been developed for the prediction and analysis of pupylated proteins and pupylation sites. However, the traditional experimental methods are laborious and time-consuming. Hence, computational algorithms are highly needed that can predict potential pupylation sites using sequence features. In this research, a new prediction model, PUP-Fuse, has been developed for pupylation site prediction by integrating multiple sequence representations. Meanwhile, we explored the five types of feature encoding approaches and three machine learning (ML) algorithms. In the final model, we integrated the successive ML scores using a linear regression model. The PUP-Fuse achieved a Mathew correlation value of 0.768 by a 10-fold cross-validation test. It also outperformed existing predictors in an independent test. The web server of the PUP-Fuse with curated datasets is freely available.
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Affiliation(s)
- Firda Nurul Auliah
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan; (F.N.A.); (A.N.N.); (M.M.H.)
| | - Andi Nur Nilamyani
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan; (F.N.A.); (A.N.N.); (M.M.H.)
| | - Watshara Shoombuatong
- Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand;
| | - Md Ashad Alam
- Tulane Center for Biomedical Informatics and Genomics, Division of Biomedical Informatics and Genomics, John W. Deming Department of Medicine, School of Medicine, Tulane University, New Orleans, LA 70112, USA;
| | - Md Mehedi Hasan
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan; (F.N.A.); (A.N.N.); (M.M.H.)
- Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan
| | - Hiroyuki Kurata
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan; (F.N.A.); (A.N.N.); (M.M.H.)
- Correspondence:
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4
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PupStruct: Prediction of Pupylated Lysine Residues Using Structural Properties of Amino Acids. Genes (Basel) 2020; 11:genes11121431. [PMID: 33260770 PMCID: PMC7761138 DOI: 10.3390/genes11121431] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/23/2020] [Accepted: 11/23/2020] [Indexed: 12/23/2022] Open
Abstract
Post-translational modification (PTM) is a critical biological reaction which adds to the diversification of the proteome. With numerous known modifications being studied, pupylation has gained focus in the scientific community due to its significant role in regulating biological processes. The traditional experimental practice to detect pupylation sites proved to be expensive and requires a lot of time and resources. Thus, there have been many computational predictors developed to challenge this issue. However, performance is still limited. In this study, we propose another computational method, named PupStruct, which uses the structural information of amino acids with a radial basis kernel function Support Vector Machine (SVM) to predict pupylated lysine residues. We compared PupStruct with three state-of-the-art predictors from the literature where PupStruct has validated a significant improvement in performance over them with statistical metrics such as sensitivity (0.9234), specificity (0.9359), accuracy (0.9296), precision (0.9349), and Mathew’s correlation coefficient (0.8616) on a benchmark dataset.
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5
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Zhan W, Hsu HC, Morgan T, Ouellette T, Burns-Huang K, Hara R, Wright AG, Imaeda T, Okamoto R, Sato K, Michino M, Ramjee M, Aso K, Meinke PT, Foley M, Nathan CF, Li H, Lin G. Selective Phenylimidazole-Based Inhibitors of the Mycobacterium tuberculosis Proteasome. J Med Chem 2019; 62:9246-9253. [PMID: 31560200 DOI: 10.1021/acs.jmedchem.9b01187] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Proteasomes of pathogenic microbes have become attractive targets for anti-infectives. Coevolving with its human host, Mycobacterium tuberculosis (Mtb) has developed mechanisms to resist host-imposed nitrosative and oxidative stresses. Genetic deletion or pharmacological inhibition of the Mtb proteasome (Mtb20S) renders nonreplicating Mtb susceptible to reactive nitrogen species in vitro and unable to survive in the lungs of mice, validating the Mtb proteasome as a promising target for anti-Mtb agents. Using a structure-guided and flow chemistry-enabled study of structure-activity relationships, we developed phenylimidazole-based peptidomimetics that are highly potent for Mtb20S. X-ray structures of selected compounds with Mtb20S shed light on their selectivity for mycobacterial over human proteasomes.
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Affiliation(s)
- Wenhu Zhan
- Department of Microbiology & Immunology , Weill Cornell Medicine , 1300 York Avenue , New York , New York 10065 , United States
| | - Hao-Chi Hsu
- Structural Biology Program , Van Andel Institute , 333 Bostwick Avenue Northeast , Grand Rapids , Michigan 49503 , United States
| | - Trevor Morgan
- Cyclofluidic Limited , Biopark Broadwater Road , Welwyn Garden City AL7 3AX , U.K
| | - Tierra Ouellette
- Department of Microbiology & Immunology , Weill Cornell Medicine , 1300 York Avenue , New York , New York 10065 , United States
| | - Kristin Burns-Huang
- Department of Microbiology & Immunology , Weill Cornell Medicine , 1300 York Avenue , New York , New York 10065 , United States
| | - Ryoma Hara
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Adrian G Wright
- Cyclofluidic Limited , Biopark Broadwater Road , Welwyn Garden City AL7 3AX , U.K
| | - Toshihiro Imaeda
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Rei Okamoto
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Kenjiro Sato
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Mayako Michino
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Manoj Ramjee
- Cyclofluidic Limited , Biopark Broadwater Road , Welwyn Garden City AL7 3AX , U.K
| | - Kazuyoshi Aso
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Peter T Meinke
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Michael Foley
- Tri-Institutional Therapeutics Discovery Institute , 413 East 69th Street , New York , New York 10065 , United States
| | - Carl F Nathan
- Department of Microbiology & Immunology , Weill Cornell Medicine , 1300 York Avenue , New York , New York 10065 , United States
| | - Huilin Li
- Structural Biology Program , Van Andel Institute , 333 Bostwick Avenue Northeast , Grand Rapids , Michigan 49503 , United States
| | - Gang Lin
- Department of Microbiology & Immunology , Weill Cornell Medicine , 1300 York Avenue , New York , New York 10065 , United States
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6
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Bao W, You ZH, Huang DS. CIPPN: computational identification of protein pupylation sites by using neural network. Oncotarget 2017; 8:108867-108879. [PMID: 29312575 PMCID: PMC5752488 DOI: 10.18632/oncotarget.22335] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 09/03/2017] [Indexed: 11/25/2022] Open
Abstract
Recently, experiments revealed the pupylation to be a signal for the selective regulation of proteins in several serious human diseases. As one of the most significant post translational modification in the field of biology and disease, pupylation has the ability to playing the key role in the regulation various diseases’ biological processes. Meanwhile, effectively identification such type modification will be helpful for proteins to perform their biological functions and contribute to understanding the molecular mechanism, which is the foundation of drug design. The existing algorithms of identification such types of modified sites often have some defects, such as low accuracy and time-consuming. In this research, the pupylation sites’ identification model, CIPPN, demonstrates better performance than other existing approaches in this field. The proposed predictor achieves Acc value of 89.12 and Mcc value of 0.7949 in 10-fold cross-validation tests in the Pupdb Database (http://cwtung.kmu.edu.tw/pupdb). Significantly, such algorithm not only investigates the sequential, structural and evolutionary hallmarks around pupylation sites but also compares the differences of pupylation from the environmental, conservative and functional characterization of substrates. Therefore, the proposed feature description approach and algorithm results prove to be useful for further experimental investigation of such modification’s identification.
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Affiliation(s)
- Wenzheng Bao
- Institute of Machine Learning and Systems Biology, School of Electronics and Information Engineering, Tongji University, Shanghai, China
| | - Zhu-Hong You
- Xinjiang Technical Institutes of Physics and Chemistry, Chinese Academy of Science, Urumqi 830011, China
| | - De-Shuang Huang
- Institute of Machine Learning and Systems Biology, School of Electronics and Information Engineering, Tongji University, Shanghai, China
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7
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Delley CL, Müller AU, Ziemski M, Weber-Ban E. Prokaryotic Ubiquitin-Like Protein and Its Ligase/Deligase Enyzmes. J Mol Biol 2017; 429:3486-3499. [PMID: 28478282 DOI: 10.1016/j.jmb.2017.04.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 04/11/2017] [Accepted: 04/28/2017] [Indexed: 11/30/2022]
Abstract
Prokaryotic ubiquitin-like protein (Pup) and the modification enzymes involved in attaching Pup to or removing it from target proteins present a fascinating example of convergent evolution with respect to eukaryotic ubiquitination. Like ubiquitin (Ub), Pup is a small protein that can be covalently attached to lysine side chains of cellular proteins, and like Ub, it can serve to recruit tagged proteins for proteasomal degradation. However, unlike Ub, Pup is conformationally highly dynamic, exhibits a different linkage connectivity to its target lysines, and its ligase belongs to a different class of enzymes than the E1/E2/E3 cascade of ubiquitination. A specific feature of actinobacteria (aside from sporadic cases in a few other lineages), pupylation appears to have evolved to provide an advantage to the bacteria under certain environmental stresses rather than act as a constitutive modification. For Mycobacterium tuberculosis, pupylation and the recruitment of pupylated substrates to the proteasome support persistence inside host macrophages during pathogenesis, rendering the Pup-proteasome system an attractive drug target. In this review, we consider the dynamic nature of Pup in relation to its function, discuss the reaction mechanisms of ligation to substrates and cleavage from pupylated substrates, and put them in context of the evolutionary history of this post-translational modification.
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Affiliation(s)
- Cyrille L Delley
- ETH Zurich, Institute of Molecular Biology & Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland
| | - Andreas U Müller
- ETH Zurich, Institute of Molecular Biology & Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland
| | - Michal Ziemski
- ETH Zurich, Institute of Molecular Biology & Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland
| | - Eilika Weber-Ban
- ETH Zurich, Institute of Molecular Biology & Biophysics, Otto-Stern-Weg 5, 8093 Zurich, Switzerland.
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8
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Imkamp F, Ziemski M, Weber-Ban E. Pupylation-dependent and -independent proteasomal degradation in mycobacteria. Biomol Concepts 2016; 6:285-301. [PMID: 26352358 DOI: 10.1515/bmc-2015-0017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/08/2015] [Indexed: 02/02/2023] Open
Abstract
Bacteria make use of compartmentalizing protease complexes, similar in architecture but not homologous to the eukaryotic proteasome, for the selective and processive removal of proteins. Mycobacteria as members of the actinobacteria harbor proteasomes in addition to the canonical bacterial degradation complexes. Mycobacterial proteasomal degradation, although not essential during normal growth, becomes critical for survival under particular environmental conditions, like, for example, during persistence of the pathogenic Mycobacterium tuberculosis in host macrophages or of environmental mycobacteria under starvation. Recruitment of protein substrates for proteasomal degradation is usually mediated by pupylation, the post-translational modification of lysine side chains with the prokaryotic ubiquitin-like protein Pup. This substrate recruitment strategy is functionally reminiscent of ubiquitination in eukaryotes, but is the result of convergent evolution, relying on chemically and structurally distinct enzymes. Pupylated substrates are recognized by the ATP-dependent proteasomal regulator Mpa that associates with the 20S proteasome core. A pupylation-independent proteasome degradation pathway has recently been discovered that is mediated by the ATP-independent bacterial proteasome activator Bpa (also referred to as PafE), and that appears to play a role under stress conditions. In this review, mechanistic principles of bacterial proteasomal degradation are discussed and compared with functionally related elements of the eukaryotic ubiquitin-proteasome system. Special attention is given to an understanding on the molecular level based on structural and biochemical analysis. Wherever available, discussion of in vivo studies is included to highlight the biological significance of this unusual bacterial degradation pathway.
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9
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Structural analysis of the dodecameric proteasome activator PafE in Mycobacterium tuberculosis. Proc Natl Acad Sci U S A 2016; 113:E1983-92. [PMID: 27001842 DOI: 10.1073/pnas.1512094113] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The human pathogen Mycobacterium tuberculosis (Mtb) requires a proteasome system to cause lethal infections in mice. We recently found that proteasome accessory factor E (PafE, Rv3780) activates proteolysis by the Mtb proteasome independently of adenosine triphosphate (ATP). Moreover, PafE contributes to the heat-shock response and virulence of Mtb Here, we show that PafE subunits formed four-helix bundles similar to those of the eukaryotic ATP-independent proteasome activator subunits of PA26 and PA28. However, unlike any other known proteasome activator, PafE formed dodecamers with 12-fold symmetry, which required a glycine-XXX-glycine-XXX-glycine motif that is not found in previously described activators. Intriguingly, the truncation of the PafE carboxyl-terminus resulted in the robust binding of PafE rings to native proteasome core particles and substantially increased proteasomal activity, suggesting that the extended carboxyl-terminus of this cofactor confers suboptimal binding to the proteasome core particle. Collectively, our data show that proteasomal activation is not limited to hexameric ATPases in bacteria.
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10
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The Absence of Pupylation (Prokaryotic Ubiquitin-Like Protein Modification) Affects Morphological and Physiological Differentiation in Streptomyces coelicolor. J Bacteriol 2015; 197:3388-99. [PMID: 26283768 DOI: 10.1128/jb.00591-15] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 08/10/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Protein turnover is essential in all living organisms for the maintenance of normal cell physiology. In eukaryotes, most cellular protein turnover involves the ubiquitin-proteasome pathway, in which proteins tagged with ubiquitin are targeted to the proteasome for degradation. In contrast, most bacteria lack a proteasome but harbor proteases for protein turnover. However, some actinobacteria, such as mycobacteria, possess a proteasome in addition to these proteases. A prokaryotic ubiquitination-like tagging process in mycobacteria was described and was named pupylation: proteins are tagged with Pup (prokaryotic ubiquitin-like protein) and directed to the proteasome for degradation. We report pupylation in another actinobacterium, Streptomyces coelicolor. Both the morphology and life cycle of Streptomyces species are complex (formation of a substrate and aerial mycelium followed by sporulation), and these bacteria are prolific producers of secondary metabolites with important medicinal and agricultural applications. The genes encoding the pupylation system in S. coelicolor are expressed at various stages of development. We demonstrated that pupylation targets numerous proteins and identified 20 of them. Furthermore, we established that abolition of pupylation has substantial effects on morphological and metabolic differentiation and on resistance to oxidative stress. In contrast, in most cases, a proteasome-deficient mutant showed only modest perturbations under the same conditions. Thus, the phenotype of the pup mutant does not appear to be due solely to defective proteasomal degradation. Presumably, pupylation has roles in addition to directing proteins to the proteasome. IMPORTANCE Streptomyces spp. are filamentous and sporulating actinobacteria, remarkable for their morphological and metabolic differentiation. They produce numerous bioactive compounds, including antifungal, antibiotic, and antitumor compounds. There is therefore considerable interest in understanding the mechanisms by which Streptomyces species regulate their complex physiology and production of bioactive compounds. We studied the role in Streptomyces of pupylation, a posttranslational modification that tags proteins that are then directed to the proteasome for degradation. We demonstrated that the absence of pupylation had large effects on morphological differentiation, antibiotic production, and resistance to oxidative stress in S. coelicolor. The phenotypes of pupylation and proteasome-defective mutants differed and suggest that pupylation acts in a proteasome-independent manner in addition to its role in proteasomal degradation.
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11
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Hasan MM, Zhou Y, Lu X, Li J, Song J, Zhang Z. Computational Identification of Protein Pupylation Sites by Using Profile-Based Composition of k-Spaced Amino Acid Pairs. PLoS One 2015; 10:e0129635. [PMID: 26080082 PMCID: PMC4469302 DOI: 10.1371/journal.pone.0129635] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 05/10/2015] [Indexed: 11/20/2022] Open
Abstract
Prokaryotic proteins are regulated by pupylation, a type of post-translational modification that contributes to cellular function in bacterial organisms. In pupylation process, the prokaryotic ubiquitin-like protein (Pup) tagging is functionally analogous to ubiquitination in order to tag target proteins for proteasomal degradation. To date, several experimental methods have been developed to identify pupylated proteins and their pupylation sites, but these experimental methods are generally laborious and costly. Therefore, computational methods that can accurately predict potential pupylation sites based on protein sequence information are highly desirable. In this paper, a novel predictor termed as pbPUP has been developed for accurate prediction of pupylation sites. In particular, a sophisticated sequence encoding scheme [i.e. the profile-based composition of k-spaced amino acid pairs (pbCKSAAP)] is used to represent the sequence patterns and evolutionary information of the sequence fragments surrounding pupylation sites. Then, a Support Vector Machine (SVM) classifier is trained using the pbCKSAAP encoding scheme. The final pbPUP predictor achieves an AUC value of 0.849 in10-fold cross-validation tests and outperforms other existing predictors on a comprehensive independent test dataset. The proposed method is anticipated to be a helpful computational resource for the prediction of pupylation sites. The web server and curated datasets in this study are freely available at http://protein.cau.edu.cn/pbPUP/.
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Affiliation(s)
- Md. Mehedi Hasan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yuan Zhou
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaotian Lu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Jinyan Li
- Advanced Analytics Institute and Centre for Health Technologies, University of Technology, Sydney, 81 Broadway, NSW 2007, Australia
| | - Jiangning Song
- National Engineering Laboratory for Industrial Enzymes and Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- Monash Bioinformatics Platform and Department of Biochemistry and Molecular Biology, Faculty of Medicine, Monash University, Melbourne, VIC 3800, Australia
| | - Ziding Zhang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
- * E-mail:
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12
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Abstract
Prokaryotes form ubiquitin (Ub)-like isopeptide bonds on the lysine residues of proteins by at least two distinct pathways that are reversible and regulated. In mycobacteria, the C-terminal Gln of Pup (prokaryotic ubiquitin-like protein) is deamidated and isopeptide linked to proteins by a mechanism distinct from ubiquitylation in enzymology yet analogous to ubiquitylation in targeting proteins for destruction by proteasomes. Ub-fold proteins of archaea (SAMPs, small archaeal modifier proteins) and Thermus (TtuB, tRNA-two-thiouridine B) that differ from Ub in amino acid sequence, yet share a common β-grasp fold, also form isopeptide bonds by a mechanism that appears streamlined compared with ubiquitylation. SAMPs and TtuB are found to be members of a small group of Ub-fold proteins that function not only in protein modification but also in sulfur-transfer pathways associated with tRNA thiolation and molybdopterin biosynthesis. These multifunctional Ub-fold proteins are thought to be some of the most ancient of Ub-like protein modifiers.
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Affiliation(s)
- Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611;
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13
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Koumandou VL, Wickstead B, Ginger ML, van der Giezen M, Dacks JB, Field MC. Molecular paleontology and complexity in the last eukaryotic common ancestor. Crit Rev Biochem Mol Biol 2014; 48:373-96. [PMID: 23895660 PMCID: PMC3791482 DOI: 10.3109/10409238.2013.821444] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Eukaryogenesis, the origin of the eukaryotic cell, represents one of the fundamental evolutionary transitions in the history of life on earth. This event, which is estimated to have occurred over one billion years ago, remains rather poorly understood. While some well-validated examples of fossil microbial eukaryotes for this time frame have been described, these can provide only basic morphology and the molecular machinery present in these organisms has remained unknown. Complete and partial genomic information has begun to fill this gap, and is being used to trace proteins and cellular traits to their roots and to provide unprecedented levels of resolution of structures, metabolic pathways and capabilities of organisms at these earliest points within the eukaryotic lineage. This is essentially allowing a molecular paleontology. What has emerged from these studies is spectacular cellular complexity prior to expansion of the eukaryotic lineages. Multiple reconstructed cellular systems indicate a very sophisticated biology, which by implication arose following the initial eukaryogenesis event but prior to eukaryotic radiation and provides a challenge in terms of explaining how these early eukaryotes arose and in understanding how they lived. Here, we provide brief overviews of several cellular systems and the major emerging conclusions, together with predictions for subsequent directions in evolution leading to extant taxa. We also consider what these reconstructions suggest about the life styles and capabilities of these earliest eukaryotes and the period of evolution between the radiation of eukaryotes and the eukaryogenesis event itself.
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Affiliation(s)
- V Lila Koumandou
- Biomedical Research Foundation, Academy of Athens, Soranou Efesiou 4, Athens 115 27, Greece
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14
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Nanduri B, Suvarnapunya AE, Venkatesan M, Edelmann MJ. Deubiquitinating enzymes as promising drug targets for infectious diseases. Curr Pharm Des 2013; 19:3234-47. [PMID: 23151130 DOI: 10.2174/1381612811319180008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 11/01/2012] [Indexed: 01/25/2023]
Abstract
Deubiquitinating enzymes (DUBs) remove ubiquitin and ubiquitin-like modifications from proteins and they have been known to contribute to processes relevant in microbial infection, such as immune responses pathways. Numerous viral and bacterial DUBs have been identified, and activities of several host DUBs are known to be modulated during the infection process, either by a pathogen or by a host. Recently there have been attempts to take advantage of this feature and design therapeutic inhibitors of DUBs that can be used to limit the spread of infection. This review is focused on exploring the potential of DUBs in the treatment of infectious diseases.
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Affiliation(s)
- Bindu Nanduri
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
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15
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Systematic analysis and prediction of pupylation sites in prokaryotic proteins. PLoS One 2013; 8:e74002. [PMID: 24019945 PMCID: PMC3760804 DOI: 10.1371/journal.pone.0074002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 06/20/2013] [Indexed: 11/19/2022] Open
Abstract
Prokaryotic ubiquitin-like protein (Pup) is the first identified prokaryotic protein that is functionally analogous to ubiquitin. Recent studies have shed light on the Pup activation and conjugation to target proteins to be a signal for the selective degradation proteins in Mycobacterium tuberculosis (Mtb). By covalently conjugating the Pup, pupylation functions as a critical post-translational modification (PTM) conserved in actinomycetes. Detecting pupylation sites is crucial and fundamental for understanding the molecular mechanisms of Pup. Yet comparative studies with other PTM suggest that the development of accurate and complete repertories of pupylation is still in its early stages. Unbiased screening for pupylation sites by experimental methods is time consuming and expensive; in silico prediction can provide highly potential candidates and reduce the number of potential candidates that require further in vivo or in vitro confirmation. Here, we present an effective classifier of PupPred for predicting pupylation sites, which shows better performance than existing classifiers. Importantly, this work not only investigates the sequential, structural and evolutionary hallmarks around pupylation sites but also compares the differences of pupylation and ubiquitylation from the environmental, conservative and functional characterization of substrates. These prediction and analysis results may be helpful for further experimental investigation of degradation proteins in prokaryotes. Finally, the PupPred server is available at http://bioinfo.ncu.edu.cn/PupPred.aspx.
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16
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Barandun J, Delley CL, Ban N, Weber-Ban E. Crystal structure of the complex between prokaryotic ubiquitin-like protein and its ligase PafA. J Am Chem Soc 2013; 135:6794-7. [PMID: 23601177 DOI: 10.1021/ja4024012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Prokaryotic ubiquitin-like protein (Pup) is covalently attached to target proteins by the ligase PafA, tagging substrates for proteasomal degradation. The crystal structure of Pup in complex with PafA, reported here, reveals that a long groove wrapping around the enzyme serves as a docking site for Pup. Upon binding, the C-terminal region of the intrinsically disordered Pup becomes ordered to form two helices connected by a linker, positioning the C-terminal glutamate in the active site of PafA.
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Affiliation(s)
- Jonas Barandun
- Institute of Molecular Biology & Biophysics, ETH Zürich, Zürich, Switzerland
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17
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Ofer N, Forer N, Korman M, Vishkautzan M, Khalaila I, Gur E. Allosteric transitions direct protein tagging by PafA, the prokaryotic ubiquitin-like protein (Pup) ligase. J Biol Chem 2013; 288:11287-93. [PMID: 23471967 DOI: 10.1074/jbc.m112.435842] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein degradation via prokaryotic ubiquitin-like protein (Pup) tagging is conserved in bacteria belonging to the phyla Actinobacteria and Nitrospira. The physiological role of this novel proteolytic pathway is not yet clear, although in Mycobacterium tuberculosis, the world's most threatening bacterial pathogen, Pup tagging is important for virulence. PafA, the Pup ligase, couples ATP hydrolysis with Pup conjugation to lysine side chains of protein substrates. PafA is the sole Pup ligase in M. tuberculosis and apparently, in other bacteria. Thus, whereas PafA is a key player in the Pup tagging (i.e. pupylation) system, control of its activity and interactions with target protein substrates remain poorly understood. In this study, we examined the mechanism of protein pupylation by PafA in Mycobacterium smegmatis, a model mycobacterial organism. We report that PafA is an allosteric enzyme that binds its target substrates cooperatively and find that PafA allostery is controlled by the binding of target protein substrates, yet is unaffected by Pup binding. Analysis of PafA pupylation using engineered substrates differing in the number of pupylation sites points to PafA acting as a dimer. These findings suggest that protein pupylation can be regulated at the level of PafA allostery.
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Affiliation(s)
- Naomi Ofer
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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18
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Ubiquitin-like proteins and their roles in archaea. Trends Microbiol 2012; 21:31-8. [PMID: 23140889 DOI: 10.1016/j.tim.2012.09.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/25/2012] [Accepted: 09/26/2012] [Indexed: 01/01/2023]
Abstract
This review highlights the finding that ubiquitin-like (Ubl) proteins of archaea (termed SAMPs) function not only as sulfur carriers but also as protein modifiers. UbaA (an E1 ubiquitin-activating enzyme homolog of archaea) is required for the SAMPs to be covalently attached to proteins. The SAMPs and UbaA are also needed to form sulfur-containing biomolecules (e.g., thiolated tRNA and molybdenum cofactor). These findings provide a new perspective on how Ubl proteins can serve as both sulfur carriers and protein modifiers in the absence of canonical E2 ubiquitin conjugating or E3 ubiquitin ligase enzyme homologs.
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19
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Burns KE, McAllister FE, Schwerdtfeger C, Mintseris J, Cerda-Maira F, Noens EE, Wilmanns M, Hubbard SR, Melandri F, Ovaa H, Gygi SP, Darwin KH. Mycobacterium tuberculosis prokaryotic ubiquitin-like protein-deconjugating enzyme is an unusual aspartate amidase. J Biol Chem 2012; 287:37522-9. [PMID: 22942282 DOI: 10.1074/jbc.m112.384784] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Deamidase of Pup (Dop), the prokaryotic ubiquitin-like protein (Pup)-deconjugating enzyme, is critical for the full virulence of Mycobacterium tuberculosis and is unique to bacteria, providing an ideal target for the development of selective chemotherapies. We used a combination of genetics and chemical biology to characterize the mechanism of depupylation. We identified an aspartate as a potential nucleophile in the active site of Dop, suggesting a novel protease activity to target for inhibitor development.
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Affiliation(s)
- Kristin E Burns
- Department of Microbiology, New York University, New York, New York 10016, USA
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20
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Merkx R, Burns KE, Slobbe P, El Oualid F, El Atmioui D, Darwin KH, Ovaa H. Synthesis and evaluation of a selective fluorogenic Pup derived assay reagent for Dop, a potential drug target in Mycobacterium tuberculosis. Chembiochem 2012; 13:2056-60. [PMID: 22927162 PMCID: PMC3474595 DOI: 10.1002/cbic.201200460] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Indexed: 01/04/2023]
Affiliation(s)
- Remco Merkx
- Division of Cell Biology, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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21
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Kim MS, Dufour YS, Yoo JS, Cho YB, Park JH, Nam GB, Kim HM, Lee KL, Donohue TJ, Roe JH. Conservation of thiol-oxidative stress responses regulated by SigR orthologues in actinomycetes. Mol Microbiol 2012; 85:326-44. [PMID: 22651816 DOI: 10.1111/j.1365-2958.2012.08115.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Numerous thiol-reactive compounds cause oxidative stress where cells counteract by activation of survival strategies regulated by thiol-based sensors. In Streptomyces coelicolor, a model actinomycete, a sigma/antisigma pair SigR/RsrA controls the response to thiol-oxidative stress. To unravel its full physiological functions, chromatin immuno-precipitation combined with sequence and transcript analyses were employed to identify 108 SigR target genes in S. coelicolor and to predict orthologous regulons across actinomycetes. In addition to reported genes for thiol homeostasis, protein degradation and ribosome modulation, 64 additional operons were identified suggesting new functions of this global regulator. We demonstrate that SigR maintains the level and activity of the housekeeping sigma factor HrdB during thiol-oxidative stress, a novel strategy for stress responses. We also found that SigR defends cells against UV and thiol-reactive damages, in which repair UvrA takes a part. Using a refined SigR-binding sequence model, SigR orthologues and their targets were predicted in 42 actinomycetes. This revealed a conserved core set of SigR targets to function for thiol homeostasis, protein quality control, possible modulation of transcription and translation, flavin-mediated redox reactions, and Fe-S delivery. The composition of the SigR regulon reveals a robust conserved physiological mechanism to deal with thiol-oxidative stress from bacteria to human.
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Affiliation(s)
- Min-Sik Kim
- Laboratory of Molecular Microbiology, School of Biological Sciences, and Institute of Microbiology, Seoul National University, Seoul 151-742, Korea
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22
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Costa ED, Chai Y, Winans SC. The quorum-sensing protein TraR of Agrobacterium tumefaciens is susceptible to intrinsic and TraM-mediated proteolytic instability. Mol Microbiol 2012; 84:807-15. [PMID: 22515735 DOI: 10.1111/j.1365-2958.2012.08037.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
TraR of Agrobacterium tumefaciens is a LuxR-type transcription factor that regulates genes required for replication and conjugation of the tumour-inducing plasmid. TraR binds the pheromone 3-oxo-octanoylhomoserine lactone (OOHL) and requires this molecule for folding into a protease-resistant, soluble conformation. Even after binding to OOHL, TraR is degraded at readily detectable rates. Here we show that the N-terminal domain of TraR, which binds OOHL, is more resistant to degradation than the full length protein, suggesting that sites on the C-terminal DNA binding domain [TraR(170-234)] enhance protein turnover. A fusion between GFP and TraR(170-234) was poorly fluorescent, and truncations of this fusion protein allowed us to identify residues in this domain that contribute to protein degradation. TraR activity was previously shown to be inhibited by the antiactivator TraM. These proteins form 2:2 complexes that fail to bind DNA sequences. Here we show that TraM sharply decreased the accumulation of TraR in whole cells, indicating that TraM facilitates proteolysis of TraR. The TraM component of these complexes is spared from proteolysis, and could therefore act catalytically.
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Affiliation(s)
- Esther D Costa
- Department of Microbiology, Cornell University, Ithaca, NY 14850, USA
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23
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Abstract
The eukaryotic ubiquitin family encompasses nearly 20 proteins that are involved in the posttranslational modification of various macromolecules. The ubiquitin-like proteins (UBLs) that are part of this family adopt the β-grasp fold that is characteristic of its founding member ubiquitin (Ub). Although structurally related, UBLs regulate a strikingly diverse set of cellular processes, including nuclear transport, proteolysis, translation, autophagy, and antiviral pathways. New UBL substrates continue to be identified and further expand the functional diversity of UBL pathways in cellular homeostasis and physiology. Here, we review recent findings on such novel substrates, mechanisms, and functions of UBLs.
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24
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Abstract
Like other energy-dependent proteases, proteasomes, which are found across the three domains of life, are self-compartmentalized and important in the early steps of proteolysis. Proteasomes degrade improperly synthesized, damaged or misfolded proteins and hydrolyse regulatory proteins that must be specifically removed or cleaved for cell signalling. In eukaryotes, proteins are typically targeted for proteasome-mediated destruction through polyubiquitylation, although ubiquitin-independent pathways also exist. Interestingly, actinobacteria and archaea also covalently attach small proteins (prokaryotic ubiquitin-like protein (Pup) and small archaeal modifier proteins (Samps), respectively) to certain proteins, and this may serve to target the modified proteins for degradation by proteasomes.
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Affiliation(s)
- Julie Maupin-Furlow
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611-0700, USA.
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25
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Abstract
AAA+ family proteolytic machines (ClpXP, ClpAP, ClpCP, HslUV, Lon, FtsH, PAN/20S, and the 26S proteasome) perform protein quality control and are used in regulatory circuits in all cells. These machines contain a compartmental protease, with active sites sequestered in an interior chamber, and a hexameric ring of AAA+ ATPases. Substrate proteins are tethered to the ring, either directly or via adaptor proteins. An unstructured region of the substrate is engaged in the axial pore of the AAA+ ring, and cycles of ATP binding/hydrolysis drive conformational changes that create pulses of pulling that denature the substrate and translocate the unfolded polypeptide through the pore and into the degradation chamber. Here, we review our current understanding of the molecular mechanisms of substrate recognition, adaptor function, and ATP-fueled unfolding and translocation. The unfolding activities of these and related AAA+ machines can also be used to disassemble or remodel macromolecular complexes and to resolubilize aggregates.
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Affiliation(s)
- Robert T Sauer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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26
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de la Vega M, Burrows JF, Johnston JA. Ubiquitination: Added complexity in Ras and Rho family GTPase function. Small GTPases 2011; 2:192-201. [PMID: 22145091 DOI: 10.4161/sgtp.2.4.16707] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 07/08/2011] [Accepted: 07/08/2011] [Indexed: 12/17/2022] Open
Abstract
The regulation of the small GTPases leading to their membrane localization has long been attributed to processing of their C-terminal CAAX box. As deregulation of many of these GTPases have been implicated in cancer and other disorders, prenylation and methylation of this CAAX box has been studied in depth as a possibility for drug targeting, but unfortunately, to date no drug has proved clinically beneficial. However, these GTPases also undergo other modifications that may be important for their regulation. Ubiquitination has long been demonstrated to regulate the fate of numerous cellular proteins and recently it has become apparent that many GTPases, along with their GAPs, GeFs and GDis, undergo ubiquitination leading to a variety of fates such as re-localization or degradation. in this review we focus on the recent literature demonstrating that the regulation of small GTPases by ubiquitination, either directly or indirectly, plays a considerable role in controlling their function and that targeting these modifications could be important for disease treatment.
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Affiliation(s)
- Michelle de la Vega
- Centre for Infection and Immunity; School of Medicine, Dentistry and Biomedical Sciences; Queen's University; Belfast, UK
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27
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Suskiewicz MJ, Sussman JL, Silman I, Shaul Y. Context-dependent resistance to proteolysis of intrinsically disordered proteins. Protein Sci 2011; 20:1285-97. [PMID: 21574196 DOI: 10.1002/pro.657] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Accepted: 05/05/2011] [Indexed: 01/08/2023]
Abstract
Intrinsically disordered proteins (IDPs), also known as intrinsically unstructured proteins (IUPs), lack a well-defined 3D structure in vitro and, in some cases, also in vivo. Here, we discuss the question of proteolytic sensitivity of IDPs, with a view to better explaining their in vivo characteristics. After an initial assessment of the status of IDPs in vivo, we briefly survey the intracellular proteolytic systems. Subsequently, we discuss the evidence for IDPs being inherently sensitive to proteolysis. Such sensitivity would not, however, result in enhanced degradation if the protease-sensitive sites were sequestered. Accordingly, IDP access to and degradation by the proteasome, the major proteolytic complex within eukaryotic cells, are discussed in detail. The emerging picture appears to be that IDPs are inherently sensitive to proteasomal degradation along the lines of the "degradation by default" model. However, available data sets of intracellular protein half-lives suggest that intrinsic disorder does not imply a significantly shorter half-life. We assess the power of available systemic half-life measurements, but also discuss possible mechanisms that could protect IDPs from intracellular degradation. Finally, we discuss the relevance of the proteolytic sensitivity of IDPs to their function and evolution.
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Affiliation(s)
- Marcin J Suskiewicz
- The Israel Structural Proteomics Center, Weizmann Institute of Science, Rehovot, Israel
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28
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Jarrell KF, Walters AD, Bochiwal C, Borgia JM, Dickinson T, Chong JPJ. Major players on the microbial stage: why archaea are important. MICROBIOLOGY-SGM 2011; 157:919-936. [PMID: 21330437 DOI: 10.1099/mic.0.047837-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
As microbiology undergoes a renaissance, fuelled in part by developments in new sequencing technologies, the massive diversity and abundance of microbes becomes yet more obvious. The Archaea have traditionally been perceived as a minor group of organisms forced to evolve into environmental niches not occupied by their more 'successful' and 'vigorous' counterparts, the bacteria. Here we outline some of the evidence gathered by an increasingly large and productive group of scientists that demonstrates not only that the Archaea contribute significantly to global nutrient cycling, but also that they compete successfully in 'mainstream' environments. Recent data suggest that the Archaea provide the major routes for ammonia oxidation in the environment. Archaea also have huge economic potential that to date has only been fully realized in the production of thermostable polymerases. Archaea have furnished us with key paradigms for understanding fundamentally conserved processes across all domains of life. In addition, they have provided numerous exemplars of novel biological mechanisms that provide us with a much broader view of the forms that life can take and the way in which micro-organisms can interact with other species. That this information has been garnered in a relatively short period of time, and appears to represent only a small proportion of what the Archaea have to offer, should provide further incentives to microbiologists to investigate the underlying biology of this fascinating domain.
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Affiliation(s)
- Ken F Jarrell
- Department of Microbiology and Immunology, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Alison D Walters
- Department of Biology, University of York, Wentworth Way, Heslington, York YO10 5DD, UK
| | - Chitvan Bochiwal
- Department of Biology, University of York, Wentworth Way, Heslington, York YO10 5DD, UK
| | - Juliet M Borgia
- Department of Biology, University of York, Wentworth Way, Heslington, York YO10 5DD, UK
| | - Thomas Dickinson
- Sheffield Hallam University, City Campus, Howard Street, Sheffield S1 1WB, UK
| | - James P J Chong
- Department of Biology, University of York, Wentworth Way, Heslington, York YO10 5DD, UK
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29
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Stallings CL, Glickman MS. Is Mycobacterium tuberculosis stressed out? A critical assessment of the genetic evidence. Microbes Infect 2010; 12:1091-101. [PMID: 20691805 PMCID: PMC3587153 DOI: 10.1016/j.micinf.2010.07.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Accepted: 07/27/2010] [Indexed: 11/17/2022]
Abstract
Mycobacterium tuberculosis is an obligate human intracellular pathogen which remains a major killer worldwide. A remarkable feature of M. tuberculosis infection is the ability of the pathogen to persist within the host for decades despite an impressive onslaught of stresses. In this review we seek to outline the host-inflicted stresses experienced by M. tuberculosis, the bacterial strategies used to withstand these stresses, and how this information should guide our efforts to combat this global pathogen.
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Affiliation(s)
- Christina L Stallings
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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30
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Burns KE, Cerda-Maira FA, Wang T, Li H, Bishai WR, Darwin KH. "Depupylation" of prokaryotic ubiquitin-like protein from mycobacterial proteasome substrates. Mol Cell 2010; 39:821-7. [PMID: 20705495 DOI: 10.1016/j.molcel.2010.07.019] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/07/2010] [Accepted: 06/29/2010] [Indexed: 01/31/2023]
Abstract
Ubiquitin (Ub) provides the recognition and specificity required to deliver proteins to the eukaryotic proteasome for destruction. Prokaryotic ubiquitin-like protein (Pup) is functionally analogous to Ub in Mycobacterium tuberculosis (Mtb), as it dooms proteins to the Mtb proteasome. Studies suggest that Pup and Ub do not share similar mechanisms of activation and conjugation to target proteins. Dop (deamidase of Pup; Mtb Rv2112c/MT2172) deamidates the C-terminal glutamine of Pup to glutamate, preparing it for ligation to target proteins by proteasome accessory factor A (PafA). While studies have shed light on the conjugation of Pup to proteins, it was not known if Pup could be removed from substrates in a manner analogous to the deconjugation of Ub from eukaryotic proteins. Here, we show that Mycobacteria have a "depupylase" activity provided by Dop. The discovery of a depupylase strengthens the parallels between the Pup- and Ub-tagging systems of prokaryotes and eukaryotes, respectively.
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Affiliation(s)
- Kristin E Burns
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
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31
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Dougan DA, Truscott KN, Zeth K. The bacterial N-end rule pathway: expect the unexpected. Mol Microbiol 2010; 76:545-58. [DOI: 10.1111/j.1365-2958.2010.07120.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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