1
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Hustmyer CM, Landick R. Bacterial chromatin proteins, transcription, and DNA topology: Inseparable partners in the control of gene expression. Mol Microbiol 2024; 122:81-112. [PMID: 38847475 PMCID: PMC11260248 DOI: 10.1111/mmi.15283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 06/15/2024]
Abstract
DNA in bacterial chromosomes is organized into higher-order structures by DNA-binding proteins called nucleoid-associated proteins (NAPs) or bacterial chromatin proteins (BCPs). BCPs often bind to or near DNA loci transcribed by RNA polymerase (RNAP) and can either increase or decrease gene expression. To understand the mechanisms by which BCPs alter transcription, one must consider both steric effects and the topological forces that arise when DNA deviates from its fully relaxed double-helical structure. Transcribing RNAP creates DNA negative (-) supercoils upstream and positive (+) supercoils downstream whenever RNAP and DNA are unable to rotate freely. This (-) and (+) supercoiling generates topological forces that resist forward translocation of DNA through RNAP unless the supercoiling is constrained by BCPs or relieved by topoisomerases. BCPs also may enhance topological stress and overall can either inhibit or aid transcription. Here, we review current understanding of how RNAP, BCPs, and DNA topology interplay to control gene expression.
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Affiliation(s)
| | - Robert Landick
- Department of Biochemistry, University of Wisconsin-Madison
- Department of Bacteriology, University of Wisconsin-Madison
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2
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Vauclare P, Wulffelé J, Lacroix F, Servant P, Confalonieri F, Kleman JP, Bourgeois D, Timmins J. Stress-induced nucleoid remodeling in Deinococcus radiodurans is associated with major changes in Heat Unstable (HU) protein dynamics. Nucleic Acids Res 2024; 52:6406-6423. [PMID: 38742631 PMCID: PMC11194088 DOI: 10.1093/nar/gkae379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 04/23/2024] [Accepted: 04/26/2024] [Indexed: 05/16/2024] Open
Abstract
Bacteria have developed a wide range of strategies to respond to stress, one of which is the rapid large-scale reorganization of their nucleoid. Nucleoid associated proteins (NAPs) are believed to be major actors in nucleoid remodeling, but the details of this process remain poorly understood. Here, using the radiation resistant bacterium D. radiodurans as a model, and advanced fluorescence microscopy, we examined the changes in nucleoid morphology and volume induced by either entry into stationary phase or exposure to UV-C light, and characterized the associated changes in mobility of the major NAP in D. radiodurans, the heat-unstable (HU) protein. While both types of stress induced nucleoid compaction, HU diffusion was reduced in stationary phase cells, but was instead increased following exposure to UV-C, suggesting distinct underlying mechanisms. Furthermore, we show that UV-C-induced nucleoid remodeling involves a rapid nucleoid condensation step associated with increased HU diffusion, followed by a slower decompaction phase to restore normal nucleoid morphology and HU dynamics, before cell division can resume. These findings shed light on the diversity of nucleoid remodeling processes in bacteria and underline the key role of HU in regulating this process through changes in its mode of assembly on DNA.
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Affiliation(s)
- Pierre Vauclare
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
| | - Jip Wulffelé
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
| | | | - Pascale Servant
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Fabrice Confalonieri
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | | | | | - Joanna Timmins
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
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3
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Santoshi M, Tare P, Nagaraja V. Nucleoid-associated proteins of mycobacteria come with a distinctive flavor. Mol Microbiol 2024. [PMID: 38922783 DOI: 10.1111/mmi.15287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/31/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024]
Abstract
In every bacterium, nucleoid-associated proteins (NAPs) play crucial roles in chromosome organization, replication, repair, gene expression, and other DNA transactions. Their central role in controlling the chromatin dynamics and transcription has been well-appreciated in several well-studied organisms. Here, we review the diversity, distribution, structure, and function of NAPs from the genus Mycobacterium. We highlight the progress made in our understanding of the effects of these proteins on various processes and in responding to environmental stimuli and stress of mycobacteria in their free-living as well as during distinctive intracellular lifestyles. We project them as potential drug targets and discuss future studies to bridge the information gap with NAPs from well-studied systems.
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Affiliation(s)
- Meghna Santoshi
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Priyanka Tare
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
- Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
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4
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Liu X, Li J, Zhang Z, He Y, Wang M, Zhao Y, Lin S, Liu T, Liao Y, Zhang N, Yuan K, Ling Y, Liu Z, Chen X, Chen Z, Chen R, Wang X, Gu B. Acetylation of xenogeneic silencer H-NS regulates biofilm development through the nitrogen homeostasis regulator in Shewanella. Nucleic Acids Res 2024; 52:2886-2903. [PMID: 38142446 PMCID: PMC11014242 DOI: 10.1093/nar/gkad1219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 12/26/2023] Open
Abstract
Adjusting intracellular metabolic pathways and adopting suitable live state such as biofilms, are crucial for bacteria to survive environmental changes. Although substantial progress has been made in understanding how the histone-like nucleoid-structuring (H-NS) protein modulates the expression of the genes involved in biofilm formation, the precise modification that the H-NS protein undergoes to alter its DNA binding activity is still largely uncharacterized. This study revealed that acetylation of H-NS at Lys19 inhibits biofilm development in Shewanella oneidensis MR-1 by downregulating the expression of glutamine synthetase, a critical enzyme in glutamine synthesis. We further found that nitrogen starvation, a likely condition in biofilm development, induces deacetylation of H-NS and the trimerization of nitrogen assimilation regulator GlnB. The acetylated H-NS strain exhibits significantly lower cellular glutamine concentration, emphasizing the requirement of H-NS deacetylation in Shewanella biofilm development. Moreover, we discovered in vivo that the activation of glutamine biosynthesis pathway and the concurrent suppression of the arginine synthesis pathway during both pellicle and attached biofilms development, further suggesting the importance of fine tune nitrogen assimilation by H-NS acetylation in Shewanella. In summary, posttranslational modification of H-NS endows Shewanella with the ability to respond to environmental needs by adjusting the intracellular metabolism pathways.
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Affiliation(s)
- Xiaoxiao Liu
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Jun Li
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Zhixuan Zhang
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
- School of Medicine, South China University of Technology, Guangzhou, Guangdong 510080, China
| | - Yizhou He
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Mingfang Wang
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Yunhu Zhao
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Shituan Lin
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianlang Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiwen Liao
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Ni Zhang
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Kaixuan Yuan
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Yong Ling
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Ziyao Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaozhong Chen
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
| | - Zhe Chen
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ran Chen
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bing Gu
- Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510000, China
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5
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Erkelens AM, van Erp B, Meijer WJJ, Dame RT. Rok from B. subtilis: Bridging genome structure and transcription regulation. Mol Microbiol 2024. [PMID: 38511404 DOI: 10.1111/mmi.15250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/02/2024] [Accepted: 03/07/2024] [Indexed: 03/22/2024]
Abstract
Bacterial genomes are folded and organized into compact yet dynamic structures, called nucleoids. Nucleoid orchestration involves many factors at multiple length scales, such as nucleoid-associated proteins and liquid-liquid phase separation, and has to be compatible with replication and transcription. Possibly, genome organization plays an intrinsic role in transcription regulation, in addition to classical transcription factors. In this review, we provide arguments supporting this view using the Gram-positive bacterium Bacillus subtilis as a model. Proteins BsSMC, HBsu and Rok all impact the structure of the B. subtilis chromosome. Particularly for Rok, there is compelling evidence that it combines its structural function with a role as global gene regulator. Many studies describe either function of Rok, but rarely both are addressed at the same time. Here, we review both sides of the coin and integrate them into one model. Rok forms unusually stable DNA-DNA bridges and this ability likely underlies its repressive effect on transcription by either preventing RNA polymerase from binding to DNA or trapping it inside DNA loops. Partner proteins are needed to change or relieve Rok-mediated gene repression. Lastly, we investigate which features characterize H-NS-like proteins, a family that, at present, lacks a clear definition.
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Affiliation(s)
- Amanda M Erkelens
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, the Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, the Netherlands
| | - Bert van Erp
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, the Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, the Netherlands
| | - Wilfried J J Meijer
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), C. Nicolás Cabrera 1, Universidad Autónoma, Madrid, Spain
| | - Remus T Dame
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, the Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, the Netherlands
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6
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Lukose B, Maruno T, Faidh M, Uchiyama S, Naganathan A. Molecular and thermodynamic determinants of self-assembly and hetero-oligomerization in the enterobacterial thermo-osmo-regulatory protein H-NS. Nucleic Acids Res 2024; 52:2157-2173. [PMID: 38340344 PMCID: PMC10954469 DOI: 10.1093/nar/gkae090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 01/03/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024] Open
Abstract
Environmentally regulated gene expression is critical for bacterial survival under stress conditions, including extremes in temperature, osmolarity and nutrient availability. Here, we dissect the thermo- and osmo-responsory behavior of the transcriptional repressor H-NS, an archetypal nucleoid-condensing sensory protein, ubiquitous in enterobacteria that infect the mammalian gut. Through experiments and thermodynamic modeling, we show that H-NS exhibits osmolarity, temperature and concentration dependent self-association, with a highly polydisperse native ensemble dominated by monomers, dimers, tetramers and octamers. The relative population of these oligomeric states is determined by an interplay between dimerization and higher-order oligomerization, which in turn drives a competition between weak homo- versus hetero-oligomerization of protein-protein and protein-DNA complexes. A phosphomimetic mutation, Y61E, fully eliminates higher-order self-assembly and preserves only dimerization while weakening DNA binding, highlighting that oligomerization is a prerequisite for strong DNA binding. We further demonstrate the presence of long-distance thermodynamic connectivity between dimerization and oligomerization sites on H-NS which influences the binding of the co-repressor Cnu, and switches the DNA binding mode of the hetero-oligomeric H-NS:Cnu complex. Our work thus uncovers important organizational principles in H-NS including a multi-layered thermodynamic control, and provides a molecular framework broadly applicable to other thermo-osmo sensory proteins that employ similar mechanisms to regulate gene expression.
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Affiliation(s)
- Bincy Lukose
- Department of Biotechnology, Bhupat & Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | | | - Mohammed A Faidh
- Department of Biotechnology, Bhupat & Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | | | - Athi N Naganathan
- Department of Biotechnology, Bhupat & Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
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7
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Liu Y, Zhou M, Bu Y, Qin L, Zhang Y, Shao S, Wang Q. Lysine acetylation regulates the AT-rich DNA possession ability of H-NS. Nucleic Acids Res 2024; 52:1645-1660. [PMID: 38059366 PMCID: PMC10899749 DOI: 10.1093/nar/gkad1172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/01/2023] [Accepted: 11/23/2023] [Indexed: 12/08/2023] Open
Abstract
H-NS, the histone-like nucleoid-structuring protein in bacteria, regulates the stability of the bacterial genome by inhibiting the transcription of horizontally transferred genes, such as the type III and type VI secretion systems (T3/T6SS). While eukaryotic histone posttranslational modifications (PTMs) have been extensively studied, little is known about prokaryotic H-NS PTMs. Here, we report that the acetylation of H-NS attenuates its ability to silence horizontally transferred genes in response to amino acid nutrition and immune metabolites. Moreover, LC-MS/MS profiling showed that the acetyllysine sites of H-NS and K120 are indispensable for its DNA-binding ability. Acetylation of K120 leads to a low binding affinity for DNA and enhances T3/T6SS expression. Furthermore, acetylation of K120 impairs the AT-rich DNA recognition ability of H-NS. In addition, lysine acetylation in H-NS modulates in vivo bacterial virulence. These findings reveal the mechanism underlying H-NS PTMs and propose a novel mechanism by which bacteria counteract the xenogeneic silencing of H-NS.
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Affiliation(s)
- Yabo Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Mengqing Zhou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yifan Bu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Liang Qin
- New Product R&D, GenScript Biotech Corporation, Nanjing 211100, China
| | - Yuanxing Zhang
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
- Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China
| | - Shuai Shao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
- Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China
| | - Qiyao Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China
- Laboratory of Aquatic Animal Diseases of MOA, Shanghai 200237, China
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8
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Norris V, Kayser C, Muskhelishvili G, Konto-Ghiorghi Y. The roles of nucleoid-associated proteins and topoisomerases in chromosome structure, strand segregation, and the generation of phenotypic heterogeneity in bacteria. FEMS Microbiol Rev 2023; 47:fuac049. [PMID: 36549664 DOI: 10.1093/femsre/fuac049] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 12/06/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
How to adapt to a changing environment is a fundamental, recurrent problem confronting cells. One solution is for cells to organize their constituents into a limited number of spatially extended, functionally relevant, macromolecular assemblies or hyperstructures, and then to segregate these hyperstructures asymmetrically into daughter cells. This asymmetric segregation becomes a particularly powerful way of generating a coherent phenotypic diversity when the segregation of certain hyperstructures is with only one of the parental DNA strands and when this pattern of segregation continues over successive generations. Candidate hyperstructures for such asymmetric segregation in prokaryotes include those containing the nucleoid-associated proteins (NAPs) and the topoisomerases. Another solution to the problem of creating a coherent phenotypic diversity is by creating a growth-environment-dependent gradient of supercoiling generated along the replication origin-to-terminus axis of the bacterial chromosome. This gradient is modulated by transcription, NAPs, and topoisomerases. Here, we focus primarily on two topoisomerases, TopoIV and DNA gyrase in Escherichia coli, on three of its NAPs (H-NS, HU, and IHF), and on the single-stranded binding protein, SSB. We propose that the combination of supercoiling-gradient-dependent and strand-segregation-dependent topoisomerase activities result in significant differences in the supercoiling of daughter chromosomes, and hence in the phenotypes of daughter cells.
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Affiliation(s)
- Vic Norris
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
| | - Clara Kayser
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
| | - Georgi Muskhelishvili
- Agricultural University of Georgia, School of Natural Sciences, 0159 Tbilisi, Georgia
| | - Yoan Konto-Ghiorghi
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
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9
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Groisman EA, Choi J. Advancing evolution: Bacteria break down gene silencer to express horizontally acquired genes. Bioessays 2023; 45:e2300062. [PMID: 37533411 PMCID: PMC10530229 DOI: 10.1002/bies.202300062] [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: 04/09/2023] [Revised: 07/25/2023] [Accepted: 07/28/2023] [Indexed: 08/04/2023]
Abstract
Horizontal gene transfer advances bacterial evolution. To benefit from horizontally acquired genes, enteric bacteria must overcome silencing caused when the widespread heat-stable nucleoid structuring (H-NS) protein binds to AT-rich horizontally acquired genes. This ability had previously been ascribed to both anti-silencing proteins outcompeting H-NS for binding to AT-rich DNA and RNA polymerase initiating transcription from alternative promoters. However, we now know that pathogenic Salmonella enterica serovar Typhimurium and commensal Escherichia coli break down H-NS when this silencer is not bound to DNA. Curiously, both species use the same protease - Lon - to destroy H-NS in distinct environments. Anti-silencing proteins promote the expression of horizontally acquired genes without binding to them by displacing H-NS from AT-rich DNA, thus leaving H-NS susceptible to proteolysis and decreasing H-NS amounts overall. Conserved amino acid sequences in the Lon protease and H-NS cleavage site suggest that diverse bacteria degrade H-NS to exploit horizontally acquired genes.
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Affiliation(s)
- 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
| | - Jeongjoon Choi
- Department of Genetics, Yale School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA
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10
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Slapakova M, Sgambati D, Pirone L, Russo V, D’Abrosca G, Valletta M, Russo R, Chambery A, Malgieri G, Pedone EM, Dame RT, Pedone PV, Baglivo I. MucR from Sinorhizobium meliloti: New Insights into Its DNA Targets and Its Ability to Oligomerize. Int J Mol Sci 2023; 24:14702. [PMID: 37834166 PMCID: PMC10572780 DOI: 10.3390/ijms241914702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
Proteins of the MucR/Ros family play a crucial role in bacterial infection or symbiosis with eukaryotic hosts. MucR from Sinorhizobium meliloti plays a regulatory role in establishing symbiosis with the host plant, both dependent and independent of Quorum Sensing. Here, we report the first characterization of MucR isolated from Sinorhizobium meliloti by mass spectrometry and demonstrate that this protein forms higher-order oligomers in its native condition of expression by SEC-MALS. We show that MucR purified from Sinorhizobium meliloti can bind DNA and recognize the region upstream of the ndvA gene in EMSA, revealing that this gene is a direct target of MucR. Although MucR DNA binding activity was already described, a detailed characterization of Sinorhizobium meliloti DNA targets has never been reported. We, thus, analyze sequences recognized by MucR in the rem gene promoter, showing that this protein recognizes AT-rich sequences and does not require a consensus sequence to bind DNA. Furthermore, we investigate the dependence of MucR DNA binding on the length of DNA targets. Taken together, our studies establish MucR from Sinorhizobium meliloti as a member of a new family of Histone-like Nucleoid Structuring (H-NS) proteins, thus explaining the multifaceted role of this protein in many species of alpha-proteobacteria.
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Affiliation(s)
- Martina Slapakova
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Domenico Sgambati
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Luciano Pirone
- Institute of Biostructures and Bioimaging, CNR, Via Pietro Castellino, 80134 Naples, Italy; (L.P.); (E.M.P.)
| | - Veronica Russo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Gianluca D’Abrosca
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy;
| | - Mariangela Valletta
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Rosita Russo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Gaetano Malgieri
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Emilia Maria Pedone
- Institute of Biostructures and Bioimaging, CNR, Via Pietro Castellino, 80134 Naples, Italy; (L.P.); (E.M.P.)
| | - Remus Thei Dame
- Leiden Institute of Chemistry, Leiden University, 2333 CC Leiden, The Netherlands;
- Centre for Microbial Cell Biology, Leiden University, 2333 CC Leiden, The Netherlands
| | - Paolo Vincenzo Pedone
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
| | - Ilaria Baglivo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Via Vivaldi, 43, 81100 Caserta, Italy; (M.S.); (D.S.); (V.R.); (M.V.); (R.R.); (A.C.); (G.M.); (P.V.P.)
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11
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Rashid FZM, Dame RT. Three-dimensional chromosome re-modelling: The integral mechanism of transcription regulation in bacteria. Mol Microbiol 2023; 120:60-70. [PMID: 37433047 DOI: 10.1111/mmi.15062] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 07/13/2023]
Abstract
Nucleoid-associated proteins (NAPs) are architectural proteins of the bacterial chromosome and transcription factors that dynamically organise the chromosome and regulate gene expression in response to physicochemical environmental signals. While the architectural and regulatory functions of NAPs have been verified independently, the coupling between these functions in vivo has not been conclusively proven. Here we describe a model NAP - histone-like nucleoid structuring protein (H-NS) - as a coupled sensor-effector that directly regulates gene expression by chromatin re-modelling in response to physicochemical environmental signals. We outline how H-NS-binding partners and post-translational modifications modulate the role of H-NS as a transcription factor by influencing its DNA structuring properties. We consolidate our ideas in models of how H-NS may regulate the expression of the proVWX and hlyCABD operons by chromatin re-modelling. The interplay between chromosome structure and gene expression may be a common - but, at present, under-appreciated - concept of transcription regulation in bacteria.
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Affiliation(s)
- Fatema-Zahra M Rashid
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
| | - Remus T Dame
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
- Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
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12
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Pat- and Pta-mediated protein acetylation is required for horizontally-acquired virulence gene expression in Salmonella Typhimurium. J Microbiol 2022; 60:823-831. [DOI: 10.1007/s12275-022-2095-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/25/2022]
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13
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Jindal S, Iyer MS, Jyoti P, Masakapalli SK, Venkatesh KV. Mutants lacking global regulators, fis and arcA, in Escherichia coli enhanced growth fitness under acetate metabolism by pathway reprogramming. Appl Microbiol Biotechnol 2022; 106:3231-3243. [PMID: 35416487 DOI: 10.1007/s00253-022-11890-6] [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: 08/13/2021] [Revised: 03/20/2022] [Accepted: 03/21/2022] [Indexed: 11/25/2022]
Abstract
Global regulatory transcription factors play a significant role in controlling microbial metabolism under genetic and environmental perturbations. A system-level effect of carbon sources such as acetate on microbial metabolism under disrupted global regulators has not been well established. Acetate is one of the major substrates available in various nutrient niches such as the mammalian gut and a keto diet. A substantial amount of acetate gets secreted in aerobic metabolism. Therefore, investigating the study on acetate metabolism is highly significant. It is known that the global regulators fis and arcA regulate acetate uptake genes in E. coli under glucose conditions. This study deciphered the growth and flux distribution of E. coli transcription regulatory knockouts Δfis, ΔarcA and double deletion mutant, ΔarcAΔfis under acetate using 13C-metabolic flux analysis (MFA), which has not been investigated before. We observed that the mutants exhibited an expeditious growth rate (~ 1.2-1.6-fold) with a proportionate increase in acetate uptake rates compared to the wild type. 13C-MFA displayed the distinct metabolic reprogramming of intracellular fluxes via the TCA cycle, anaplerotic pathway and gluconeogenesis, which conferred an advantage of a faster growth rate with better carbon usage in all the mutants. This resulted in higher metabolic fluxes through the TCA cycle (~ 18-90%), lower gluconeogenesis (~ 15-35%) and higher CO2 and ATP production with the proportional increase in growth rate. The study reveals a novel insight by stating the sub-optimality of the wild-type strain grown under acetate substrate aerobically. These mutant strains efficiently oxidize acetate, thus acting as potential candidates for the biosynthesis of isoprenoids, biofuels, vitamins and various pharmaceutical products.Key Points• Mutants exhibited a better balance between energy and precursor synthesis than WT.• Leveraged in the unravelling of regulatory control under various nutrient shifts.• Metabolic readjustment resulted in optimal biomass requirement and faster growth.
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Affiliation(s)
- Shikha Jindal
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Mahesh S Iyer
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Poonam Jyoti
- BioX Center, School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, 175075, India
| | - Shyam Kumar Masakapalli
- BioX Center, School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, 175075, India.
| | - K V Venkatesh
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.
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14
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Abstract
The DNA-binding protein from starved cells, Dps, is a universally conserved prokaryotic ferritin that, in many species, also binds DNA. Dps homologs have been identified in the vast majority of bacterial species and several archaea. Dps also may play a role in the global regulation of gene expression, likely through chromatin reorganization. Dps has been shown to use both its ferritin and DNA-binding functions to respond to a variety of environmental pressures, including oxidative stress. One mechanism that allows Dps to achieve this is through a global nucleoid restructuring event during stationary phase, resulting in a compact, hexacrystalline nucleoprotein complex called the biocrystal that occludes damaging agents from DNA. Due to its small size, hollow spherical structure, and high stability, Dps is being developed for applications in biotechnology.
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15
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Cajili MKM, Prieto EI. Interplay between Alba and Cren7 Regulates Chromatin Compaction in Sulfolobus solfataricus. Biomolecules 2022; 12:biom12040481. [PMID: 35454068 PMCID: PMC9030869 DOI: 10.3390/biom12040481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/03/2022] [Accepted: 03/15/2022] [Indexed: 01/06/2023] Open
Abstract
Chromatin compaction and regulation are essential processes for the normal function of all organisms, yet knowledge on how archaeal chromosomes are packed into higher-order structures inside the cell remains elusive. In this study, we investigated the role of archaeal architectural proteins Alba and Cren7 in chromatin folding and dynamics. Atomic force microscopy revealed that Sulfolobus solfataricus chromatin is composed of 28 nm fibers and 60 nm globular structures. In vitro reconstitution showed that Alba can mediate the formation of folded DNA structures in a concentration-dependent manner. Notably, it was demonstrated that Alba on its own can form higher-order structures with DNA. Meanwhile, Cren7 was observed to affect the formation of Alba-mediated higher-order chromatin structures. Overall, the results suggest an interplay between Alba and Cren7 in regulating chromatin compaction in archaea.
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16
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Dong H, Zhao Y, Bi C, Han Y, Zhang J, Bai X, Zhai G, Zhang H, Tian S, Hu D, Xu L, Zhang K. TmcA functions as a lysine 2-hydroxyisobutyryltransferase to regulate transcription. Nat Chem Biol 2022; 18:142-151. [PMID: 34903851 DOI: 10.1038/s41589-021-00906-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 09/23/2021] [Indexed: 02/05/2023]
Abstract
Protein lysine 2-hydroxyisobutyrylation (Khib) has recently been shown to play a critical role in the regulation of cellular processes. However, the mechanism and functional consequence of Khib in prokaryotes remain unclear. Here we report that TmcA, an RNA acetyltransferase, functions as a lysine 2-hydroxyisobutyryltransferase in the regulation of transcription. We show that TmcA can effectively catalyze Khib both in vitro and intracellularly, and that R502 is a key site for the Khib catalytic activity of TmcA. Using quantitative proteomics, we identified 467 endogenous candidates targeted by TmcA for Khib in Escherichia coli. Interestingly, we demonstrate that TmcA can specifically modulate the DNA-binding activity of H-NS, a nucleoid-associated protein, by catalysis of Khib at K121. Furthermore, this TmcA-targeted Khib regulates transcription of acid-resistance genes and enhances E. coli survival under acid stress. Our study reveals transcription regulation mediated by TmcA-catalyzed Khib for bacterial acid resistance.
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Affiliation(s)
- Hanyang Dong
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou, China
| | - Yujie Zhao
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Changfen Bi
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Peking Union Medical College & Chinese Academy of Medical Sciences, Tianjin, China
| | - Yue Han
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Jianji Zhang
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Xue Bai
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Guijin Zhai
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Hui Zhang
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Shanshan Tian
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - Deqing Hu
- Tianjin Key Laboratory of Medical Epigenetics, Department of Cell Biology, Tianjin Medical University, Tianjin, China
| | - Liyan Xu
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou, China
| | - Kai Zhang
- The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China.
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17
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Nagaraja V, Singh PR. Challenges in elucidating bacteria-host epigenetic dynamics. Epigenomics 2021; 14:69-72. [PMID: 34676777 DOI: 10.2217/epi-2021-0357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Valakunja Nagaraja
- Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, 560012, India.,Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
| | - Prakruti R Singh
- Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, 560012, India
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18
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The yeast mitochondrial succinylome: Implications for regulation of mitochondrial nucleoids. J Biol Chem 2021; 297:101155. [PMID: 34480900 PMCID: PMC8477199 DOI: 10.1016/j.jbc.2021.101155] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 08/23/2021] [Accepted: 08/30/2021] [Indexed: 11/22/2022] Open
Abstract
Acylation modifications, such as the succinylation of lysine, are post-translational modifications and a powerful means of regulating protein activity. Some acylations occur nonenzymatically, driven by an increase in the concentration of acyl group donors. Lysine succinylation has a profound effect on the corresponding site within the protein, as it dramatically changes the charge of the residue. In eukaryotes, it predominantly affects mitochondrial proteins because the donor of succinate, succinyl-CoA, is primarily generated in the tricarboxylic acid cycle. Although numerous succinylated mitochondrial proteins have been identified in Saccharomyces cerevisiae, a more detailed characterization of the yeast mitochondrial succinylome is still lacking. Here, we performed a proteomic MS analysis of purified yeast mitochondria and detected 314 succinylated mitochondrial proteins with 1763 novel succinylation sites. The mitochondrial nucleoid, a complex of mitochondrial DNA and mitochondrial proteins, is one of the structures whose protein components are affected by succinylation. We found that Abf2p, the principal component of mitochondrial nucleoids responsible for compacting mitochondrial DNA in S. cerevisiae, can be succinylated in vivo on at least thirteen lysine residues. Abf2p succinylation in vitro inhibits its DNA-binding activity and reduces its sensitivity to digestion by the ATP-dependent ScLon protease. We conclude that changes in the metabolic state of a cell resulting in an increase in the concentration of tricarboxylic acid intermediates may affect mitochondrial functions.
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19
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Amemiya HM, Schroeder J, Freddolino PL. Nucleoid-associated proteins shape chromatin structure and transcriptional regulation across the bacterial kingdom. Transcription 2021; 12:182-218. [PMID: 34499567 PMCID: PMC8632127 DOI: 10.1080/21541264.2021.1973865] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/15/2021] [Accepted: 08/18/2021] [Indexed: 01/21/2023] Open
Abstract
Genome architecture has proven to be critical in determining gene regulation across almost all domains of life. While many of the key components and mechanisms of eukaryotic genome organization have been described, the interplay between bacterial DNA organization and gene regulation is only now being fully appreciated. An increasing pool of evidence has demonstrated that the bacterial chromosome can reasonably be thought of as chromatin, and that bacterial chromosomes contain transcriptionally silent and transcriptionally active regions analogous to heterochromatin and euchromatin, respectively. The roles played by histones in eukaryotic systems appear to be shared across a range of nucleoid-associated proteins (NAPs) in bacteria, which function to compact, structure, and regulate large portions of bacterial chromosomes. The broad range of extant NAPs, and the extent to which they differ from species to species, has raised additional challenges in identifying and characterizing their roles in all but a handful of model bacteria. Here we review the regulatory roles played by NAPs in several well-studied bacteria and use the resulting state of knowledge to provide a working definition for NAPs, based on their function, binding pattern, and expression levels. We present a screening procedure which can be applied to any species for which transcriptomic data are available. Finally, we note that NAPs tend to play two major regulatory roles - xenogeneic silencers and developmental regulators - and that many unrecognized potential NAPs exist in each bacterial species examined.
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Affiliation(s)
- Haley M. Amemiya
- University of Michigan Medical School, Ann Arbor, MI, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jeremy Schroeder
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Peter L. Freddolino
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
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20
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Interplay between Nucleoid-Associated Proteins and Transcription Factors in Controlling Specialized Metabolism in Streptomyces. mBio 2021; 12:e0107721. [PMID: 34311581 PMCID: PMC8406272 DOI: 10.1128/mbio.01077-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Lsr2 is a small nucleoid-associated protein found throughout the actinobacteria. Lsr2 functions similarly to the well-studied H-NS, in that it preferentially binds AT-rich sequences and represses gene expression. In Streptomyces venezuelae, Lsr2 represses the expression of many specialized metabolic clusters, including the chloramphenicol antibiotic biosynthetic gene cluster, and deleting lsr2 leads to significant upregulation of chloramphenicol cluster expression. We show here that Lsr2 likely exerts its repressive effects on the chloramphenicol cluster by polymerizing along the chromosome and by bridging sites within and adjacent to the chloramphenicol cluster. CmlR is a known activator of the chloramphenicol cluster, but expression of its associated gene is not upregulated in an lsr2 mutant strain. We demonstrate that CmlR is essential for chloramphenicol production, and further reveal that CmlR functions to “countersilence” Lsr2’s repressive effects by recruiting RNA polymerase and enhancing transcription, with RNA polymerase effectively clearing bound Lsr2 from the chloramphenicol cluster DNA. Our results provide insight into the interplay between opposing regulatory proteins that govern antibiotic production in S. venezuelae, which could be exploited to maximize the production of bioactive natural products in other systems.
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21
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Protein acetyltransferases mediate bacterial adaptation to a diverse environment. J Bacteriol 2021; 203:e0023121. [PMID: 34251868 DOI: 10.1128/jb.00231-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Protein lysine acetylation is a conserved post-translational modification that modulates several cellular processes. Protein acetylation and its physiological implications are well understood in eukaryotes; however, its role is emerging in bacteria. Lysine acetylation in bacteria is fine-tuned by the concerted action of lysine acetyltransferases (KATs), protein deacetylases (KDACs), metabolic intermediates- acetyl-coenzyme A (Ac-CoA) and acetyl phosphate (AcP). AcP mediated nonenzymatic acetylation is predominant in bacteria due to its high acetyl transfer potential whereas, enzymatic acetylation by bacterial KATs (bKAT) are considered less abundant. SePat, the first bKAT discovered in Salmonella enterica, regulates the activity of the central metabolic enzyme- acetyl-CoA synthetase, through its acetylation. Recent studies have highlighted the role of bKATs in stress responses like pH tolerance, nutrient stress, persister cell formation, antibiotic resistance and pathogenesis. Bacterial genomes encode many putative bKATs of unknown biological function and significance. Detailed characterization of putative and partially characterized bKATs is important to decipher the acetylation mediated regulation in bacteria. Proper synthesis of information about the diverse roles of bKATs is missing to date, which can lead to the discovery of new antimicrobial targets in future. In this review, we provide an overview of the diverse physiological roles of known bKATs, and their mode of regulation in different bacteria. We also highlight existing gaps in the literature and present questions that may help understand the regulatory mechanisms mediated by bKATs in adaptation to a diverse habitat.
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22
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Anand C, Santoshi M, Singh PR, Nagaraja V. Rv0802c is an acyltransferase that succinylates and acetylates Mycobacterium tuberculosis nucleoid-associated protein HU. MICROBIOLOGY-SGM 2021; 167. [PMID: 34224344 DOI: 10.1099/mic.0.001058] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Among the nucleoid-associated proteins (NAPs), HU is the most conserved in eubacteria, engaged in overall chromosome organization and regulation of gene expression. Unlike other bacteria, HU from Mycobacterium tuberculosis (MtHU), has a long carboxyl terminal domain enriched in basic amino acids, resembling eukaryotic histone N-terminal tails. As with histones, MtHU undergoes post-translational modifications and we have previously identified interacting kinases, methyltransferases, an acetyltransferase and a deacetylase. Here we show that Rv0802c interacts and succinylates MtHU. Although categorized as a succinyltransferase, we show that this GNAT superfamily member can catalyse both succinylation and acetylation of MtHU with comparable kinetic parameters. Like acetylation of MtHU, succinylation of MtHU caused reduced interaction of the NAP with DNA, determined by electrophoretic mobility shift assay and surface plasmon resonance. However, in vivo expression of Rv0802c did not significantly alter the nucleoid architecture. Although such succinylation of NAPs is rare, these modifications of the archetypal NAP may provide avenues to the organism to compensate for the underrepresentation of NAPs in its genome to control the dynamics of nucleoid architecture and cellular functions.
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Affiliation(s)
- Chinmay Anand
- Department of Microbiology and Cell biology, Indian Institute of Science, Bengaluru, Karnataka 560012, India
| | - Meghna Santoshi
- Department of Microbiology and Cell biology, Indian Institute of Science, Bengaluru, Karnataka 560012, India
| | - Prakruti R Singh
- Department of Microbiology and Cell biology, Indian Institute of Science, Bengaluru, Karnataka 560012, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell biology, Indian Institute of Science, Bengaluru, Karnataka 560012, India.,Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka 560064, India
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23
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Liu X, Lin S, Liu T, Zhou Y, Wang W, Yao J, Guo Y, Tang K, Chen R, Benedik MJ, Wang X. Xenogeneic silencing relies on temperature-dependent phosphorylation of the host H-NS protein in Shewanella. Nucleic Acids Res 2021; 49:3427-3440. [PMID: 33693785 PMCID: PMC8034616 DOI: 10.1093/nar/gkab137] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/17/2021] [Accepted: 02/20/2021] [Indexed: 12/20/2022] Open
Abstract
Lateral gene transfer (LGT) plays a key role in shaping the genome evolution and environmental adaptation of bacteria. Xenogeneic silencing is crucial to ensure the safe acquisition of LGT genes into host pre-existing regulatory networks. We previously found that the host nucleoid structuring protein (H-NS) silences prophage CP4So at warm temperatures yet enables this prophage to excise at cold temperatures in Shewanella oneidensis. However, whether H-NS silences other genes and how bacteria modulate H-NS to regulate the expression of genes have not been fully elucidated. In this study, we discovered that the H-NS silences many LGT genes and the xenogeneic silencing of H-NS relies on a temperature-dependent phosphorylation at warm temperatures in S. oneidensis. Specifically, phosphorylation of H-NS at Ser42 is critical for silencing the cold-inducible genes including the excisionase of CP4So prophage, a cold shock protein, and a stress-related chemosensory system. By contrast, nonphosphorylated H-NS derepresses the promoter activity of these genes/operons to enable their expression at cold temperatures. Taken together, our results reveal that the posttranslational modification of H-NS can function as a regulatory switch to control LGT gene expression in host genomes to enable the host bacterium to react and thrive when environmental temperature changes.
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Affiliation(s)
- Xiaoxiao Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Shituan Lin
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianlang Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiqing Zhou
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiquan Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianyun Yao
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Yunxue Guo
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Ran Chen
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China
| | - Michael J Benedik
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 1119, Haibin Road, Nansha District, Guangzhou 511458, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), No.1119, Haibin Road, Nansha District, Guangzhou 511458, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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24
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Deter HS, Hossain T, Butzin NC. Antibiotic tolerance is associated with a broad and complex transcriptional response in E. coli. Sci Rep 2021; 11:6112. [PMID: 33731833 PMCID: PMC7969968 DOI: 10.1038/s41598-021-85509-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/02/2021] [Indexed: 02/06/2023] Open
Abstract
Antibiotic treatment kills a large portion of a population, while a small, tolerant subpopulation survives. Tolerant bacteria disrupt antibiotic efficacy and increase the likelihood that a population gains antibiotic resistance, a growing health concern. We examined how E. coli transcriptional networks changed in response to lethal ampicillin concentrations. We are the first to apply transcriptional regulatory network (TRN) analysis to antibiotic tolerance by leveraging existing knowledge and our transcriptional data. TRN analysis shows that gene expression changes specific to ampicillin treatment are likely caused by specific sigma and transcription factors typically regulated by proteolysis. These results demonstrate that to survive lethal concentration of ampicillin specific regulatory proteins change activity and cause a coordinated transcriptional response that leverages multiple gene systems.
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Affiliation(s)
- Heather S Deter
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Tahmina Hossain
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57006, USA
| | - Nicholas C Butzin
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57006, USA.
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25
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Birnie A, Dekker C. Genome-in-a-Box: Building a Chromosome from the Bottom Up. ACS NANO 2021; 15:111-124. [PMID: 33347266 PMCID: PMC7844827 DOI: 10.1021/acsnano.0c07397] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/16/2020] [Indexed: 05/24/2023]
Abstract
Chromosome structure and dynamics are essential for life, as the way that our genomes are spatially organized within cells is crucial for gene expression, differentiation, and genome transfer to daughter cells. There is a wide variety of methods available to study chromosomes, ranging from live-cell studies to single-molecule biophysics, which we briefly review. While these technologies have yielded a wealth of data, such studies still leave a significant gap between top-down experiments on live cells and bottom-up in vitro single-molecule studies of DNA-protein interactions. Here, we introduce "genome-in-a-box" (GenBox) as an alternative in vitro approach to build and study chromosomes, which bridges this gap. The concept is to assemble a chromosome from the bottom up by taking deproteinated genome-sized DNA isolated from live cells and subsequently add purified DNA-organizing elements, followed by encapsulation in cell-sized containers using microfluidics. Grounded in the rationale of synthetic cell research, the approach would enable to experimentally study emergent effects at the global genome level that arise from the collective action of local DNA-structuring elements. We review the various DNA-structuring elements present in nature, from nucleoid-associated proteins and SMC complexes to phase separation and macromolecular crowders. Finally, we discuss how GenBox can contribute to several open questions on chromosome structure and dynamics.
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Affiliation(s)
- Anthony Birnie
- Department of Bionanoscience, Kavli
Institute of Nanoscience Delft, Delft University
of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli
Institute of Nanoscience Delft, Delft University
of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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26
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Regulation of gene expression by protein lysine acetylation in Salmonella. J Microbiol 2020; 58:979-987. [PMID: 33201432 DOI: 10.1007/s12275-020-0483-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/12/2020] [Accepted: 10/12/2020] [Indexed: 10/23/2022]
Abstract
Protein lysine acetylation influences many physiological functions, such as gene regulation, metabolism, and disease in eukaryotes. Although little is known about the role of lysine acetylation in bacteria, several reports have proposed its importance in various cellular processes. Here, we discussed the function of the protein lysine acetylation and the post-translational modifications (PTMs) of histone-like proteins in bacteria focusing on Salmonella pathogenicity. The protein lysine residue in Salmonella is acetylated by the Pat-mediated enzymatic pathway or by the acetyl phosphate-mediated non-enzymatic pathway. In Salmonella, the acetylation of lysine 102 and lysine 201 on PhoP inhibits its protein activity and DNA-binding, respectively. Lysine acetylation of the transcriptional regulator, HilD, also inhibits pathogenic gene expression. Moreover, it has been reported that the protein acetylation patterns significantly differ in the drug-resistant and -sensitive Salmonella strains. In addition, nucleoid-associated proteins such as histone-like nucleoid structuring protein (H-NS) are critical for the gene silencing in bacteria, and PTMs in H-NS also affect the gene expression. In this review, we suggest that protein lysine acetylation and the post-translational modifications of H-NS are important factors in understanding the regulation of gene expression responsible for pathogenicity in Salmonella.
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27
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Vozáriková V, Kunová N, Bauer JA, Frankovský J, Kotrasová V, Procházková K, Džugasová V, Kutejová E, Pevala V, Nosek J, Tomáška Ľ. Mitochondrial HMG-Box Containing Proteins: From Biochemical Properties to the Roles in Human Diseases. Biomolecules 2020; 10:biom10081193. [PMID: 32824374 PMCID: PMC7463775 DOI: 10.3390/biom10081193] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial DNA (mtDNA) molecules are packaged into compact nucleo-protein structures called mitochondrial nucleoids (mt-nucleoids). Their compaction is mediated in part by high-mobility group (HMG)-box containing proteins (mtHMG proteins), whose additional roles include the protection of mtDNA against damage, the regulation of gene expression and the segregation of mtDNA into daughter organelles. The molecular mechanisms underlying these functions have been identified through extensive biochemical, genetic, and structural studies, particularly on yeast (Abf2) and mammalian mitochondrial transcription factor A (TFAM) mtHMG proteins. The aim of this paper is to provide a comprehensive overview of the biochemical properties of mtHMG proteins, the structural basis of their interaction with DNA, their roles in various mtDNA transactions, and the evolutionary trajectories leading to their rapid diversification. We also describe how defects in the maintenance of mtDNA in cells with dysfunctional mtHMG proteins lead to different pathologies at the cellular and organismal level.
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Affiliation(s)
- Veronika Vozáriková
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovakia; (V.V.); (J.F.); (K.P.); (V.D.)
| | - Nina Kunová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia; (N.K.); (J.A.B.); (V.K.); (E.K.); (V.P.)
| | - Jacob A. Bauer
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia; (N.K.); (J.A.B.); (V.K.); (E.K.); (V.P.)
| | - Ján Frankovský
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovakia; (V.V.); (J.F.); (K.P.); (V.D.)
| | - Veronika Kotrasová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia; (N.K.); (J.A.B.); (V.K.); (E.K.); (V.P.)
| | - Katarína Procházková
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovakia; (V.V.); (J.F.); (K.P.); (V.D.)
| | - Vladimíra Džugasová
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovakia; (V.V.); (J.F.); (K.P.); (V.D.)
| | - Eva Kutejová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia; (N.K.); (J.A.B.); (V.K.); (E.K.); (V.P.)
| | - Vladimír Pevala
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia; (N.K.); (J.A.B.); (V.K.); (E.K.); (V.P.)
| | - Jozef Nosek
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina CH-1, 842 15 Bratislava, Slovakia;
| | - Ľubomír Tomáška
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovakia; (V.V.); (J.F.); (K.P.); (V.D.)
- Correspondence: ; Tel.: +421-2-90149-433
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28
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Novak J, Fabrik I, Jurnecka D, Holubova J, Stanek O, Sebo P. Bordetella pertussis Acetylome is Shaped by Lysine Deacetylase Bkd1. J Proteome Res 2020; 19:3680-3696. [PMID: 32674575 DOI: 10.1021/acs.jproteome.0c00178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Post-translational modifications of proteins enable swift physiological adaptation of cells to altered growth conditions and stress. Aside from protein phosphorylation, acetylation on ε-amino groups of lysine residues (N-ε-lysine acetylation) represents another important post-translational modification of proteins. For many bacterial pathogens, including the whooping cough agent Bordetella pertussis, the role and extent of protein acetylation remain to be defined. We expressed in Escherichia coli the BP0960 and BP3063 genes encoding two putative deacetylases of B. pertussis and show that BP0960 encodes a lysine deacetylase enzyme, named Bkd1, that regulates acetylation of a range of B. pertussis proteins. Comparison of the proteome and acetylome of a Δbkd1 mutant with the proteome and acetylome of wild-type B. pertussis (PRIDE ID. PXD016384) revealed that acetylation on lysine residues may modulate activities or stabilities of proteins involved in bacterial metabolism and histone-like proteins. However, increased acetylation of the BvgA response regulator protein of the B. pertussis master virulence-regulating BvgAS two-component system affected neither the total levels of produced BvgA nor its phosphorylation status. Indeed, the Δbkd1 mutant was not impaired in the production of key virulence factors and its survival within human macrophages in vitro was not affected. The Δbkd1 mutant exhibited an increased growth rate under carbon source-limiting conditions and its virulence in the in vivo mouse lung infection model was somewhat affected. These results indicate that the lysine deacetylase Bkd1 and N-ε-lysine acetylation primarily modulate the general metabolism rather than the virulence of B. pertussis.
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Affiliation(s)
- Jakub Novak
- Institute of Microbiology of the Czech Academy of Sciences, Prague 14220, Czech Republic.,Faculty of Science, Charles University, Prague 11636, Czech Republic
| | - Ivo Fabrik
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove 50005, Czech Republic
| | - David Jurnecka
- Institute of Microbiology of the Czech Academy of Sciences, Prague 14220, Czech Republic.,Faculty of Science, Charles University, Prague 11636, Czech Republic
| | - Jana Holubova
- Institute of Microbiology of the Czech Academy of Sciences, Prague 14220, Czech Republic
| | - Ondrej Stanek
- Institute of Microbiology of the Czech Academy of Sciences, Prague 14220, Czech Republic
| | - Peter Sebo
- Institute of Microbiology of the Czech Academy of Sciences, Prague 14220, Czech Republic
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29
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Hołówka J, Zakrzewska-Czerwińska J. Nucleoid Associated Proteins: The Small Organizers That Help to Cope With Stress. Front Microbiol 2020; 11:590. [PMID: 32373086 PMCID: PMC7177045 DOI: 10.3389/fmicb.2020.00590] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 03/18/2020] [Indexed: 12/11/2022] Open
Abstract
The bacterial chromosome must be efficiently compacted to fit inside the small and crowded cell while remaining accessible for the protein complexes involved in replication, transcription, and DNA repair. The dynamic organization of the nucleoid is a consequence of both intracellular factors (i.e., simultaneously occurring cell processes) and extracellular factors (e.g., environmental conditions, stress agents). Recent studies have revealed that the bacterial chromosome undergoes profound topological changes under stress. Among the many DNA-binding proteins that shape the bacterial chromosome structure in response to various signals, NAPs (nucleoid associated proteins) are the most abundant. These small, basic proteins bind DNA with low specificity and can influence chromosome organization under changing environmental conditions (i.e., by coating the chromosome in response to stress) or regulate the transcription of specific genes (e.g., those involved in virulence).
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Affiliation(s)
- Joanna Hołówka
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
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30
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Qin L, Erkelens AM, Ben Bdira F, Dame RT. The architects of bacterial DNA bridges: a structurally and functionally conserved family of proteins. Open Biol 2019; 9:190223. [PMID: 31795918 PMCID: PMC6936261 DOI: 10.1098/rsob.190223] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/08/2019] [Indexed: 12/15/2022] Open
Abstract
Every organism across the tree of life compacts and organizes its genome with architectural chromatin proteins. While eukaryotes and archaea express histone proteins, the organization of bacterial chromosomes is dependent on nucleoid-associated proteins. In Escherichia coli and other proteobacteria, the histone-like nucleoid structuring protein (H-NS) acts as a global genome organizer and gene regulator. Functional analogues of H-NS have been found in other bacterial species: MvaT in Pseudomonas species, Lsr2 in actinomycetes and Rok in Bacillus species. These proteins complement hns- phenotypes and have similar DNA-binding properties, despite their lack of sequence homology. In this review, we focus on the structural and functional characteristics of these four architectural proteins. They are able to bridge DNA duplexes, which is key to genome compaction, gene regulation and their response to changing conditions in the environment. Structurally the domain organization and charge distribution of these proteins are conserved, which we suggest is at the basis of their conserved environment responsive behaviour. These observations could be used to find and validate new members of this protein family and to predict their response to environmental changes.
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Affiliation(s)
- L. Qin
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
| | - A. M. Erkelens
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
| | - F. Ben Bdira
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
| | - R. T. Dame
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands
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31
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Chromosome organization in bacteria: mechanistic insights into genome structure and function. Nat Rev Genet 2019; 21:227-242. [DOI: 10.1038/s41576-019-0185-4] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2019] [Indexed: 12/28/2022]
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32
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Pfeifer E, Hünnefeld M, Popa O, Frunzke J. Impact of Xenogeneic Silencing on Phage-Host Interactions. J Mol Biol 2019; 431:4670-4683. [PMID: 30796986 PMCID: PMC6925973 DOI: 10.1016/j.jmb.2019.02.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 01/21/2023]
Abstract
Phages, viruses that prey on bacteria, are the most abundant and diverse inhabitants of the Earth. Temperate bacteriophages can integrate into the host genome and, as so-called prophages, maintain a long-term association with their host. The close relationship between host and virus has significantly shaped microbial evolution and phage elements may benefit their host by providing new functions. Nevertheless, the strong activity of phage promoters and potentially toxic gene products may impose a severe fitness burden and must be tightly controlled. In this context, xenogeneic silencing (XS) proteins, which can recognize foreign DNA elements, play an important role in the acquisition of novel genetic information and facilitate the evolution of regulatory networks. Currently known XS proteins fall into four classes (H-NS, MvaT, Rok and Lsr2) and have been shown to follow a similar mode of action by binding to AT-rich DNA and forming an oligomeric nucleoprotein complex that silences gene expression. In this review, we focus on the role of XS proteins in phage-host interactions by highlighting the important function of XS proteins in maintaining the lysogenic state and by providing examples of how phages fight back by encoding inhibitory proteins that disrupt XS functions in the host. Sequence analysis of available phage genomes revealed the presence of genes encoding Lsr2-type proteins in the genomes of phages infecting Actinobacteria. These data provide an interesting perspective for future studies to elucidate the impact of phage-encoded XS homologs on the phage life cycle and phage-host interactions.
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Affiliation(s)
- Eugen Pfeifer
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany.
| | - Max Hünnefeld
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany
| | - Ovidiu Popa
- Heinrich Heine Universität Düsseldorf, Institute for Quantitative and Theoretical Biology, 40223 Düsseldorf, Germany
| | - Julia Frunzke
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany.
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33
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Alqaseer K, Turapov O, Barthe P, Jagatia H, De Visch A, Roumestand C, Wegrzyn M, Bartek IL, Voskuil MI, O'Hare HM, Ajuh P, Bottrill AR, Witney AA, Cohen-Gonsaud M, Waddell SJ, Mukamolova GV. Protein kinase B controls Mycobacterium tuberculosis growth via phosphorylation of the transcriptional regulator Lsr2 at threonine 112. Mol Microbiol 2019; 112:1847-1862. [PMID: 31562654 PMCID: PMC6906086 DOI: 10.1111/mmi.14398] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2019] [Indexed: 01/23/2023]
Abstract
Mycobacterium tuberculosis (Mtb) is able to persist in the body through months of multi‐drug therapy. Mycobacteria possess a wide range of regulatory proteins, including the protein kinase B (PknB) which controls peptidoglycan biosynthesis during growth. Here, we observed that depletion of PknB resulted in specific transcriptional changes that are likely caused by reduced phosphorylation of the H‐NS‐like regulator Lsr2 at threonine 112. The activity of PknB towards this phosphosite was confirmed with purified proteins, and this site was required for adaptation of Mtb to hypoxic conditions, and growth on solid media. Like H‐NS, Lsr2 binds DNA in sequence‐dependent and non‐specific modes. PknB phosphorylation of Lsr2 reduced DNA binding, measured by fluorescence anisotropy and electrophoretic mobility shift assays, and our NMR structure of phosphomimetic T112D Lsr2 suggests that this may be due to increased dynamics of the DNA‐binding domain. Conversely, the phosphoablative T112A Lsr2 had increased binding to certain DNA sites in ChIP‐sequencing, and Mtb containing this variant showed transcriptional changes that correspond with the change in DNA binding. In summary, PknB controls Mtb growth and adaptations to the changing host environment by phosphorylating the global transcriptional regulator Lsr2.
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Affiliation(s)
- Kawther Alqaseer
- Leicester Tuberculosis Research Group, Department of Respiratory Sciences, University of Leicester, Leicester, LE2 9HN, UK.,Department of Basic Science, Faculty of Nursing, University of Kufa, Najaf Governorate, P.O. Box 21, Kufa, Najaf, Iraq
| | - Obolbek Turapov
- Leicester Tuberculosis Research Group, Department of Respiratory Sciences, University of Leicester, Leicester, LE2 9HN, UK
| | - Philippe Barthe
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, 34090, Montpellier, France
| | - Heena Jagatia
- Wellcome Trust Brighton and Sussex Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX, UK
| | - Angélique De Visch
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, 34090, Montpellier, France
| | - Christian Roumestand
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, 34090, Montpellier, France
| | - Malgorzata Wegrzyn
- Core Biotechnology Services, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Iona L Bartek
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Martin I Voskuil
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Helen M O'Hare
- Leicester Tuberculosis Research Group, Department of Respiratory Sciences, University of Leicester, Leicester, LE2 9HN, UK.,LISCB, Department of Molecular and Cell Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Paul Ajuh
- Gemini Biosciences Ltd, Liverpool Science Park, Liverpool, L7 8TX, UK
| | - Andrew R Bottrill
- Protein Nucleic Acid Laboratory, University of Leicester, Leicester, LE1 7RH, UK
| | - Adam A Witney
- Institute for Infection and Immunity, St George's University of London, London, SW17 0RE, UK
| | - Martin Cohen-Gonsaud
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, 34090, Montpellier, France
| | - Simon J Waddell
- Wellcome Trust Brighton and Sussex Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX, UK
| | - Galina V Mukamolova
- Leicester Tuberculosis Research Group, Department of Respiratory Sciences, University of Leicester, Leicester, LE2 9HN, UK
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34
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Shen BA, Landick R. Transcription of Bacterial Chromatin. J Mol Biol 2019; 431:4040-4066. [PMID: 31153903 PMCID: PMC7248592 DOI: 10.1016/j.jmb.2019.05.041] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 12/12/2022]
Abstract
Decades of research have probed the interplay between chromatin (genomic DNA associated with proteins and RNAs) and transcription by RNA polymerase (RNAP) in all domains of life. In bacteria, chromatin is compacted into a membrane-free region known as the nucleoid that changes shape and composition depending on the bacterial state. Transcription plays a key role in both shaping the nucleoid and organizing it into domains. At the same time, chromatin impacts transcription by at least five distinct mechanisms: (i) occlusion of RNAP binding; (ii) roadblocking RNAP progression; (iii) constraining DNA topology; (iv) RNA-mediated interactions; and (v) macromolecular demixing and heterogeneity, which may generate phase-separated condensates. These mechanisms are not mutually exclusive and, in combination, mediate gene regulation. Here, we review the current understanding of these mechanisms with a focus on gene silencing by H-NS, transcription coordination by HU, and potential phase separation by Dps. The myriad questions about transcription of bacterial chromatin are increasingly answerable due to methodological advances, enabling a needed paradigm shift in the field of bacterial transcription to focus on regulation of genes in their native state. We can anticipate answers that will define how bacterial chromatin helps coordinate and dynamically regulate gene expression in changing environments.
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Affiliation(s)
- Beth A Shen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Robert Landick
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States; Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, United States.
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Flores-Ríos R, Quatrini R, Loyola A. Endogenous and Foreign Nucleoid-Associated Proteins of Bacteria: Occurrence, Interactions and Effects on Mobile Genetic Elements and Host's Biology. Comput Struct Biotechnol J 2019; 17:746-756. [PMID: 31303979 PMCID: PMC6606824 DOI: 10.1016/j.csbj.2019.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 02/08/2023] Open
Abstract
Mobile Genetic Elements (MGEs) are mosaics of functional gene modules of diverse evolutionary origin and are generally divergent from the hosts´ genetic background. Existing biases in base composition and codon usage of these elements` genes impose transcription and translation limitations that may affect the physical and regulatory integration of MGEs in new hosts. Stable appropriation of the foreign DNA depends on a number of host factors among which are the Nucleoid-Associated Proteins (NAPs). These small, basic, highly abundant proteins bind and bend DNA, altering its topology and folding, thereby affecting all known essential DNA metabolism related processes. Both chromosomally- (endogenous) and MGE- (foreign) encoded NAPs have been shown to exist in bacteria. While the role of host-encoded NAPs in xenogeneic silencing of both episomal (plasmids) and integrative MGEs (pathogenicity islands and prophages) is well acknowledged, less is known about the role of MGE-encoded NAPs in the foreign elements biology or their influence on the host's chromosome expression dynamics. Here we review existing literature on the topic, present examples on the positive and negative effects that endogenous and foreign NAPs exert on global transcriptional gene expression, MGE integrative and excisive recombination dynamics, persistence and transfer to suitable hosts and discuss the nature and relevance of synergistic and antagonizing higher order interactions between diverse types of NAPs.
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Affiliation(s)
| | - Raquel Quatrini
- Fundación Ciencia y Vida, Avenida Zañartu 1482, Ñuñoa, Santiago, Chile.,Millennium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - Alejandra Loyola
- Fundación Ciencia y Vida, Avenida Zañartu 1482, Ñuñoa, Santiago, Chile
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Rovinskiy NS, Agbleke AA, Chesnokova ON, Higgins NP. Supercoil Levels in E. coli and Salmonella Chromosomes Are Regulated by the C-Terminal 35⁻38 Amino Acids of GyrA. Microorganisms 2019; 7:E81. [PMID: 30875939 PMCID: PMC6463007 DOI: 10.3390/microorganisms7030081] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 03/08/2019] [Accepted: 03/09/2019] [Indexed: 02/06/2023] Open
Abstract
Prokaryotes have an essential gene-gyrase-that catalyzes negative supercoiling of plasmid and chromosomal DNA. Negative supercoils influence DNA replication, transcription, homologous recombination, site-specific recombination, genetic transposition and sister chromosome segregation. Although E. coli and Salmonella Typhimurium are close relatives with a conserved set of essential genes, E. coli DNA has a supercoil density 15% higher than Salmonella, and E. coli cannot grow at the supercoil density maintained by wild type (WT) Salmonella. E. coli is addicted to high supercoiling levels for efficient chromosomal folding. In vitro experiments were performed with four gyrase isoforms of the tetrameric enzyme (GyrA₂:GyrB₂). E. coli gyrase was more processive and faster than the Salmonella enzyme, but Salmonella strains with chromosomal swaps of E. coli GyrA lost 40% of the chromosomal supercoil density. Reciprocal experiments in E. coli showed chromosomal dysfunction for strains harboring Salmonella GyrA. One GyrA segment responsible for dis-regulation was uncovered by constructing and testing GyrA chimeras in vivo. The six pinwheel elements and the C-terminal 35⁻38 acidic residues of GyrA controlled WT chromosome-wide supercoiling density in both species. A model of enzyme processivity modulated by competition between DNA and the GyrA acidic tail for access to β-pinwheel elements is presented.
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Affiliation(s)
- Nikolay S Rovinskiy
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0024, USA.
| | - Andrews A Agbleke
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0024, USA.
| | - Olga N Chesnokova
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0024, USA.
| | - N Patrick Higgins
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0024, USA.
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