1
|
Ravinath R, Usha T, Das AJ, Sarangi AN, Sarvashiva Kiran N, Kumar Goyal A, Krishnareddy Prasannakumar M, Ramesh N, Middha SK. Pomegranate Rhizosphere Microbial Diversity Revealed by Metagenomics: Toward Organic Farming, Plant Growth Promotion and Biocontrol? OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2024; 28:303-318. [PMID: 38805323 DOI: 10.1089/omi.2023.0272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Food production must undergo systems change to meet the sustainable development goals (SDGs). For example, organic farming can be empowered by soil microorganisms with plant growth promotion (PGP) and biocontrol features. In this context, there have been limited studies on pomegranate. We investigated microbial diversity in rhizosphere of the pomegranate "Bhagwa" variety and its potential role in PGP and biocontrol. Both bulk and rhizosphere soil samples were analyzed for their physicochemical properties. Whole metagenome sequencing was conducted using the Illumina NovaSeq6000 platform. Surprisingly, we found that bulk and rhizosphere soil samples had comparable microbial diversity. Metagenome sequencing revealed the abundance of Streptomyces indicus, Bradyrhizobium kalamazoonesis, and Pseudomonas cellulosum in the rhizosphere that are reported here for the first time in agricultural literature. Pathway prediction analysis using KEGG (Kyoto Encyclopedia for Genes and Genomes) and COG (clusters of orthologous genes) databases identified metabolic pathways associated with biocontrol properties against pathogens. We confirmed the metagenome data in vitro, which demonstrated their PGP potential and antimicrobial properties. For instance, S. indicus produced high concentration of indole-3-acetic acid, a PGP phytohormone, that can stimulate plant growth. In addition, an antimicrobial susceptibility assay suggested that bacterial extracts displayed activity against Xanthomonas, a primary pathogen causing the pomegranate wilt disease. In conclusion, this study suggests that S. indicus, B. kalamazoonesis, and P. cellulosum can potentially be PGP and biocontrol agents that may contribute to increased crop productivity in pomegranate cultivation. These agents and their combinations warrant future research with an eye on SDGs and so as to enable and innovate organic farming and pomegranate agricultural practices.
Collapse
Affiliation(s)
- Renuka Ravinath
- Department of Biotechnology, School of Applied Sciences, REVA University, Bengaluru, India
| | - Talambedu Usha
- Department of Biochemistry, Maharani Lakshmi Ammanni College for Women, Bengaluru, India
| | - Anupam J Das
- Department of Biotechnology, School of Applied Sciences, REVA University, Bengaluru, India
| | | | | | | | | | - Nijalingappa Ramesh
- Department of Biotechnology, School of Applied Sciences, REVA University, Bengaluru, India
| | - Sushil Kumar Middha
- Department of Biotechnology, Maharani Lakshmi Ammanni College for Women, Bengaluru, India
| |
Collapse
|
2
|
Ludwig J, Mrázek J. OrthoRefine: automated enhancement of prior ortholog identification via synteny. BMC Bioinformatics 2024; 25:163. [PMID: 38664637 PMCID: PMC11044567 DOI: 10.1186/s12859-024-05786-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 04/15/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND Identifying orthologs continues to be an early and imperative step in genome analysis but remains a challenging problem. While synteny (conservation of gene order) has previously been used independently and in combination with other methods to identify orthologs, applying synteny in ortholog identification has yet to be automated in a user-friendly manner. This desire for automation and ease-of-use led us to develop OrthoRefine, a standalone program that uses synteny to refine ortholog identification. RESULTS We developed OrthoRefine to improve the detection of orthologous genes by implementing a look-around window approach to detect synteny. We tested OrthoRefine in tandem with OrthoFinder, one of the most used software for identification of orthologs in recent years. We evaluated improvements provided by OrthoRefine in several bacterial and a eukaryotic dataset. OrthoRefine efficiently eliminates paralogs from orthologous groups detected by OrthoFinder. Using synteny increased specificity and functional ortholog identification; additionally, analysis of BLAST e-value, phylogenetics, and operon occurrence further supported using synteny for ortholog identification. A comparison of several window sizes suggested that smaller window sizes (eight genes) were generally the most suitable for identifying orthologs via synteny. However, larger windows (30 genes) performed better in datasets containing less closely related genomes. A typical run of OrthoRefine with ~ 10 bacterial genomes can be completed in a few minutes on a regular desktop PC. CONCLUSION OrthoRefine is a simple-to-use, standalone tool that automates the application of synteny to improve ortholog detection. OrthoRefine is particularly efficient in eliminating paralogs from orthologous groups delineated by standard methods.
Collapse
Affiliation(s)
- J Ludwig
- Institute of Bioinformatics, The University of Georgia, Athens, GA, 30602, USA.
| | - J Mrázek
- Department of Microbiology and Institute of Bioinformatics, The University of Georgia, Athens, GA, 30602, USA
| |
Collapse
|
3
|
Cheema HS, Maurya A, Kumar S, Pandey VK, Singh RM. Antibiotic Potentiation Through Phytochemical-Based Efflux Pump Inhibitors to Combat Multidrug Resistance Bacteria. Med Chem 2024; 20:557-575. [PMID: 37907487 DOI: 10.2174/0115734064263586231022135644] [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: 06/28/2023] [Revised: 09/13/2023] [Accepted: 09/21/2023] [Indexed: 11/02/2023]
Abstract
BACKGROUND Antimicrobial resistance development poses a significant danger to the efficacy of antibiotics, which were once believed to be the most efficient method for treating infections caused by bacteria. Antimicrobial resistance typically involves various mechanisms, such as drug inactivation or modification, drug target modification, drug uptake restriction, and drug efflux, resulting in decreased antibiotic concentrations within the cell. Antimicrobial resistance has been associated with efflux Pumps, known for their capacity to expel different antibiotics from the cell non-specifically. This makes EPs fascinating targets for creating drugs to combat antimicrobial resistance (AMR). The varied structures of secondary metabolites (phytomolecules) found in plants have positioned them as a promising reservoir of efflux pump inhibitors. These inhibitors act as modifiers of bacterial resistance and facilitate the reintroduction of antibiotics that have lost clinical effectiveness. Additionally, they may play a role in preventing the emergence of multidrug resistant strains. OBJECTIVE The objective of this review article is to discuss the latest studies on plant-based efflux pump inhibitors such as terpenoids, alkaloids, flavonoids, glycosides, and tetralones. It highlighted their potential in enhancing the effectiveness of antibiotics and combating the development of multidrug resistance. RESULTS Efflux pump inhibitors (EPIs) derived from botanical sources, including compounds like lysergol, chanaoclavine, niazrin, 4-hydroxy-α-tetralone, ursolic acid, phytol, etc., as well as their partially synthesized forms, have shown significant potential as practical therapeutic approaches in addressing antimicrobial resistance caused by efflux pumps. Further, several phyto-molecules and their analogs demonstrated superior potential for reversing drug resistance, surpassing established agents like reserpine, niaziridin, etc. Conclusion: This review found that while the phyto-molecules and their derivatives did not possess notable antimicrobial activity, their combination with established antibiotics significantly reduced their minimum inhibitory concentration (MIC). Specific molecules, such as chanaoclavine and niaziridin, exhibited noteworthy potential in reversing the effectiveness of drugs, resulting in a reduction of the MIC of tetracycline by up to 16 times against the tested strain of bacteria. These molecules inhibited the efflux pumps responsible for drug resistance and displayed a stronger affinity for membrane proteins. By employing powerful EPIs, these molecules can selectively target and obstruct drug efflux pumps. This targeted approach can significantly augment the strength and efficacy of older antibiotics against various drug resistant bacteria, given that active drug efflux poses a susceptibility for nearly all antibiotics.
Collapse
Affiliation(s)
| | - Anupam Maurya
- Chemistry Section, Pharmacopoeia Commission for Indian Medicine, and Homoeopathy (PCIM&H), Ministry of Ayush, Ghaziabad, 201002, (U.P.), India
| | - Sandeep Kumar
- Department of Botany, Meerut College, Meerut, 250003 (U.P.), India
| | - Vineet Kumar Pandey
- Chemistry Section, Pharmacopoeia Commission for Indian Medicine, and Homoeopathy (PCIM&H), Ministry of Ayush, Ghaziabad, 201002, (U.P.), India
| | - Raman Mohan Singh
- Chemistry Section, Pharmacopoeia Commission for Indian Medicine, and Homoeopathy (PCIM&H), Ministry of Ayush, Ghaziabad, 201002, (U.P.), India
| |
Collapse
|
4
|
GpsB Promotes PASTA Kinase Signaling and Cephalosporin Resistance in Enterococcus faecalis. J Bacteriol 2022; 204:e0030422. [PMID: 36094306 PMCID: PMC9578390 DOI: 10.1128/jb.00304-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Enterococci are opportunistic pathogens that can cause severe bacterial infections. Treatment of these infections is challenging because enterococci possess intrinsic and acquired mechanisms of resistance to commonly used antibiotics, including cephalosporins. The transmembrane serine/threonine PASTA kinase, IreK, is an important determinant of enterococcal cephalosporin resistance. Upon exposure to cephalosporins, IreK becomes autophosphorylated, which stimulates its kinase activity to phosphorylate downstream substrates and drive cephalosporin resistance. However, the molecular mechanisms that modulate IreK autophosphorylation in response to cell wall stress, such as that induced by cephalosporins, remain unknown. A cytoplasmic protein, GpsB, promotes signaling by PASTA kinase homologs in other bacterial species, but the function of enterococcal GpsB has not been previously investigated. We used in vitro and in vivo approaches to test the hypothesis that enterococcal GpsB promotes IreK signaling in response to cephalosporins to drive cephalosporin resistance. We found that GpsB promotes IreK activity both in vivo and in vitro. This effect is required for cephalosporins to trigger IreK autophosphorylation and activation of an IreK-dependent signaling pathway, and thereby is also required for enterococcal intrinsic cephalosporin resistance. Moreover, analyses of GpsB mutants and a ΔireK gpsB double mutant suggest that GpsB has an additional function, beyond regulation of IreK activity, which is required for optimal growth and full cephalosporin resistance. Collectively, our data provide new insights into the mechanism of signal transduction by the PASTA kinase IreK and the mechanism of enterococcal intrinsic cephalosporin resistance. IMPORTANCE Enterococci are opportunistic pathogens that can cause severe bacterial infections. Treatment of these infections is challenging because enterococci possess intrinsic and acquired resistance to commonly used antibiotics. In particular, enterococci are intrinsically resistant to cephalosporin antibiotics, a trait that requires the activity of a transmembrane serine/threonine kinase, IreK, which belongs to the bacterial PASTA kinase family. The mechanisms by which PASTA kinases are regulated in cells are poorly understood. Here, we report that the cytoplasmic protein GpsB directly promotes IreK signaling in enterococci to drive cephalosporin resistance. Thus, we provide new insights into PASTA kinase regulation and control of enterococcal cephalosporin resistance, and suggest that GpsB could be a promising target for new therapeutics to disable cephalosporin resistance.
Collapse
|
5
|
Abril AG, Quintela-Baluja M, Villa TG, Calo-Mata P, Barros-Velázquez J, Carrera M. Proteomic Characterization of Virulence Factors and Related Proteins in Enterococcus Strains from Dairy and Fermented Food Products. Int J Mol Sci 2022; 23:ijms231810971. [PMID: 36142880 PMCID: PMC9503237 DOI: 10.3390/ijms231810971] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/08/2022] [Accepted: 09/16/2022] [Indexed: 01/23/2023] Open
Abstract
Enterococcus species are Gram-positive bacteria that are normal gastrointestinal tract inhabitants that play a beneficial role in the dairy and meat industry. However, Enterococcus species are also the causative agents of health care-associated infections that can be found in dairy and fermented food products. Enterococcal infections are led by strains of Enterococcus faecalis and Enterococcus faecium, which are often resistant to antibiotics and biofilm formation. Enterococci virulence factors attach to host cells and are also involved in immune evasion. LC-MS/MS-based methods offer several advantages compared with other approaches because one can directly identify microbial peptides without the necessity of inferring conclusions based on other approaches such as genomics tools. The present study describes the use of liquid chromatography−electrospray ionization tandem mass spectrometry (LC−ESI−MS/MS) to perform a global shotgun proteomics characterization for opportunistic pathogenic Enterococcus from different dairy and fermented food products. This method allowed the identification of a total of 1403 nonredundant peptides, representing 1327 proteins. Furthermore, 310 of those peptides corresponded to proteins playing a direct role as virulence factors for Enterococcus pathogenicity. Virulence factors, antibiotic sensitivity, and proper identification of the enterococcal strain are required to propose an effective therapy. Data are available via ProteomeXchange with identifier PXD036435. Label-free quantification (LFQ) demonstrated that the majority of the high-abundance proteins corresponded to E. faecalis species. Therefore, the global proteomic repository obtained here can be the basis for further research into pathogenic Enterococcus species, thus facilitating the development of novel therapeutics.
Collapse
Affiliation(s)
- Ana G. Abril
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15898 Santiago de Compostela, Spain
- Department of Food Technology, Spanish National Research Council (CSIC), Marine Research Institute (IIM), 36208 Vigo, Spain
| | - Marcos Quintela-Baluja
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain
| | - Tomás G. Villa
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15898 Santiago de Compostela, Spain
| | - Pilar Calo-Mata
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain
| | - Jorge Barros-Velázquez
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain
| | - Mónica Carrera
- Department of Food Technology, Spanish National Research Council (CSIC), Marine Research Institute (IIM), 36208 Vigo, Spain
- Correspondence:
| |
Collapse
|
6
|
Penicillin-Binding Protein 1 (PBP1) of Staphylococcus aureus Has Multiple Essential Functions in Cell Division. mBio 2022; 13:e0066922. [PMID: 35703435 PMCID: PMC9426605 DOI: 10.1128/mbio.00669-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Bacterial cell division is a complex process requiring the coordination of multiple components to allow the appropriate spatial and temporal control of septum formation and cell scission. Peptidoglycan (PG) is the major structural component of the septum, and our recent studies in the human pathogen Staphylococcus aureus have revealed a complex, multistage PG architecture that develops during septation. Penicillin-binding proteins (PBPs) are essential for the final steps of PG biosynthesis; their transpeptidase activity links the peptide side chains of nascent glycan strands. PBP1 is required for cell division in S. aureus, and here, we demonstrate that it has multiple essential functions associated with its enzymatic activity and as a regulator of division. Loss of PBP1, or just its C-terminal PASTA domains, results in cessation of division at the point of septal plate formation. The PASTA domains can bind PG and thereby potentially coordinate the cell division process. The transpeptidase activity of PBP1 is also essential, but its loss leads to a strikingly different phenotype of thickened and aberrant septa, which is phenocopied by the morphological effects of adding the PBP1-specific β-lactam, meropenem. Together, these results lead to a model for septal PG synthesis where PBP1 enzyme activity is required for the characteristic architecture of the septum and PBP1 protein molecules enable the formation of the septal plate.
Collapse
|
7
|
Martínez-Caballero S, Mahasenan KV, Kim C, Molina R, Feltzer R, Lee M, Bouley R, Hesek D, Fisher JF, Muñoz IG, Chang M, Mobashery S, Hermoso JA. Integrative structural biology of the penicillin-binding protein-1 from Staphylococcus aureus, an essential component of the divisome machinery. Comput Struct Biotechnol J 2021; 19:5392-5405. [PMID: 34667534 PMCID: PMC8493512 DOI: 10.1016/j.csbj.2021.09.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 12/18/2022] Open
Abstract
The penicillin-binding proteins are the enzyme catalysts of the critical transpeptidation crosslinking polymerization reaction of bacterial peptidoglycan synthesis and the molecular targets of the penicillin antibiotics. Here, we report a combined crystallographic, small-angle X-ray scattering (SAXS) in-solution structure, computational and biophysical analysis of PBP1 of Staphylococcus aureus (saPBP1), providing mechanistic clues about its function and regulation during cell division. The structure reveals the pedestal domain, the transpeptidase domain, and most of the linker connecting to the "penicillin-binding protein and serine/threonine kinase associated" (PASTA) domains, but not its two PASTA domains, despite their presence in the construct. To address this absence, the structure of the PASTA domains was determined at 1.5 Å resolution. Extensive molecular-dynamics simulations interpret the PASTA domains of saPBP1 as conformationally mobile and separated from the transpeptidase domain. This conclusion was confirmed by SAXS experiments on the full-length protein in solution. A series of crystallographic complexes with β-lactam antibiotics (as inhibitors) and penta-Gly (as a substrate mimetic) allowed the molecular characterization of both inhibition by antibiotics and binding for the donor and acceptor peptidoglycan strands. Mass-spectrometry experiments with synthetic peptidoglycan fragments revealed binding by PASTA domains in coordination with the remaining domains. The observed mobility of the PASTA domain in saPBP1 could play a crucial role for in vivo interaction with its glycosyltransferase partner in the membrane or with other components of the divisome machinery, as well as for coordination of transpeptidation and polymerization processes in the bacterial divisome.
Collapse
Affiliation(s)
- Siseth Martínez-Caballero
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC, 28006 Madrid, Spain
| | - Kiran V Mahasenan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Choon Kim
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Rafael Molina
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC, 28006 Madrid, Spain
| | - Rhona Feltzer
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Mijoon Lee
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Renee Bouley
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Dusan Hesek
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Jed F Fisher
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Inés G Muñoz
- Structural Biology Programme, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain
| | - Mayland Chang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Juan A Hermoso
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC, 28006 Madrid, Spain
| |
Collapse
|
8
|
Are antibacterial effects of non-antibiotic drugs random or purposeful because of a common evolutionary origin of bacterial and mammalian targets? Infection 2020; 49:569-589. [PMID: 33325009 PMCID: PMC7737717 DOI: 10.1007/s15010-020-01547-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 10/28/2020] [Indexed: 01/09/2023]
Abstract
Purpose Advances in structural biology, genetics, bioinformatics, etc. resulted in the availability of an enormous pool of information enabling the analysis of the ancestry of pro- and eukaryotic genes and proteins. Methods This review summarizes findings of structural and/or functional homologies of pro- and eukaryotic enzymes catalysing analogous biological reactions because of their highly conserved active centres so that non-antibiotics interacted with bacterial targets. Results Protease inhibitors such as staurosporine or camostat inhibited bacterial serine/threonine or serine/tyrosine protein kinases, serine/threonine phosphatases, and serine/threonine kinases, to which penicillin-binding-proteins are linked, so that these drugs synergized with β-lactams, reverted aminoglycoside-resistance and attenuated bacterial virulence. Calcium antagonists such as nitrendipine or verapamil blocked not only prokaryotic ion channels but interacted with negatively charged bacterial cell membranes thus disrupting membrane energetics and inducing membrane stress response resulting in inhibition of P-glycoprotein such as bacterial pumps thus improving anti-mycobacterial activities of rifampicin, tetracycline, fluoroquinolones, bedaquilin and imipenem-activity against Acinetobacter spp. Ciclosporine and tacrolimus attenuated bacterial virulence. ACE-inhibitors like captopril interacted with metallo-β-lactamases thus reverting carbapenem-resistance; prokaryotic carbonic anhydrases were inhibited as well resulting in growth impairment. In general, non-antibiotics exerted weak antibacterial activities on their own but synergized with antibiotics, and/or reverted resistance and/or attenuated virulence. Conclusions Data summarized in this review support the theory that prokaryotic proteins represent targets for non-antibiotics because of a common evolutionary origin of bacterial- and mammalian targets resulting in highly conserved active centres of both, pro- and eukaryotic proteins with which the non-antibiotics interact and exert antibacterial actions.
Collapse
|
9
|
Abo-Kadoum MA, Assad M, Dai Y, Lambert N, Moure UAE, Eltoukhy A, Nzaou SAE, Moaaz A, Xie J. Mycobacterium tuberculosis Raf kinase inhibitor protein (RKIP) Rv2140c is involved in cell wall arabinogalactan biosynthesis via phosphorylation. Microbiol Res 2020; 242:126615. [PMID: 33189070 DOI: 10.1016/j.micres.2020.126615] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/19/2020] [Accepted: 09/28/2020] [Indexed: 12/17/2022]
Abstract
Mycobacterium tuberculosis Rv2140c is a function unknown conserved phosphatidylethanolamine-binding protein (PEBP), homologous to Raf kinase inhibitor protein (RKIP) in human beings. To delineate its function, we heterologously expressed Rv2140c in a non-pathogenic M. smegmatis. Quantitative phosphoproteomic analysis between two recombinant strains Ms_Rv2140c and Ms_vec revealed that Rv2140c differentially regulate 425 phosphorylated sites representing 282 proteins. Gene ontology GO, and a cluster of orthologous groups COG analyses showed that regulated phosphoproteins by Rv2140c were mainly associated with metabolism and cellular processes. Rv2140c significantly repressed phosphoproteins involved in signaling, including serine/threonine-protein kinases and two-component system, and the arabinogalactan biosynthesis pathway phosphoproteins were markedly up-regulated, suggesting a role of Rv2140c in modulating cell wall. Consistent with phosphoproteomic data, Rv2140c altered some phenotypic properties of M. smegmatis such as colony morphology, cell wall permeability, survival in acidic conditions, and active lactose transport. In summary, we firstly demonstrated the role of PEBP protein Rv2140c, especially in phosphorylation of mycobacterial arabinogalactan biosynthesis proteins.
Collapse
Affiliation(s)
- M A Abo-Kadoum
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China; Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Assuit Branch, Egypt
| | - Mohammed Assad
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Yongdong Dai
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Nzungize Lambert
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Ulrich Aymard Ekomi Moure
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Adel Eltoukhy
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Assuit Branch, Egypt; Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Stech A E Nzaou
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Asmaa Moaaz
- The State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China.
| |
Collapse
|
10
|
Stokas H, Rhodes HL, Purdy GE. Modulation of the M. tuberculosis cell envelope between replicating and non-replicating persistent bacteria. Tuberculosis (Edinb) 2020; 125:102007. [PMID: 33035766 DOI: 10.1016/j.tube.2020.102007] [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] [Received: 07/21/2020] [Revised: 09/24/2020] [Accepted: 10/02/2020] [Indexed: 12/18/2022]
Abstract
The success of Mycobacterium tuberculosis as a human pathogen depends on the bacterium's ability to persist in a quiescent form in oxygen and nutrient-poor host environments. In vitro studies have demonstrated that these restricting environments induce a shift from bacterial replication to non-replicating persistence (NRP). Entry into NRP involves changes in bacterial metabolism and remodeling of the cell envelope. Findings consistent with the phenotypes observed in vitro have been observed in patient and animal model samples. This review focuses on the cell envelope differences seen between replicating and NRP M. tuberculosis and summarizes the ways in which serine/threonine protein kinases (STPKs) may mediate this process.
Collapse
Affiliation(s)
- Haley Stokas
- Oregon Health & Science University, Department of Molecular Microbiology & Immunology, Portland, OR, 97239, United States
| | - Heather L Rhodes
- Oregon Health & Science University, Department of Molecular Microbiology & Immunology, Portland, OR, 97239, United States
| | - Georgiana E Purdy
- Oregon Health & Science University, Department of Molecular Microbiology & Immunology, Portland, OR, 97239, United States.
| |
Collapse
|
11
|
Djorić D, Minton NE, Kristich CJ. The enterococcal PASTA kinase: A sentinel for cell envelope stress. Mol Oral Microbiol 2020; 36:132-144. [PMID: 32945615 DOI: 10.1111/omi.12313] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/05/2020] [Accepted: 09/08/2020] [Indexed: 12/12/2022]
Abstract
Enterococci are Gram-positive, opportunistic pathogens that reside throughout the gastrointestinal tracts of most terrestrial organisms. Enterococci are resistant to many antibiotics, which makes enterococcal infections difficult to treat. Enterococci are also particularly hardy bacteria that can tolerate a variety of environmental stressors. Understanding how enterococci sense and respond to the extracellular environment to enact adaptive biological responses may identify new targets that can be exploited for development of treatments for enterococcal infections. Bacterial eukaryotic-like serine/threonine kinases (eSTKs) and cognate phosphatases (STPs) are important signaling systems that mediate biological responses to extracellular stimuli. Some bacterial eSTKs are transmembrane proteins that contain a series of extracellular repeats of the penicillin-binding and Ser/Thr kinase-associated (PASTA) domain, leading to their designation as "PASTA kinases." Enterococcal genomes encode a single PASTA kinase and its cognate phosphatase. Investigations of the enterococcal PASTA kinase revealed its importance in resistance to antibiotics and other cell wall stresses, in enterococcal colonization of the mammalian gut, clues about its mechanism of signal transduction, and its integration with other enterococcal signal transduction systems. In this review, we describe the current state of knowledge of PASTA kinase signaling in enterococci and describe important gaps that still need to be addressed to provide a better understanding of this important signaling system.
Collapse
Affiliation(s)
- Dušanka Djorić
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Nicole E Minton
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Christopher J Kristich
- Department of Microbiology and Immunology, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| |
Collapse
|
12
|
Morales Angeles D, Macia-Valero A, Bohorquez LC, Scheffers DJ. The PASTA domains of Bacillus subtilis PBP2B strengthen the interaction of PBP2B with DivIB. MICROBIOLOGY (READING, ENGLAND) 2020; 166:826-836. [PMID: 32749956 PMCID: PMC7654742 DOI: 10.1099/mic.0.000957] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/13/2020] [Indexed: 12/15/2022]
Abstract
Bacterial cell division is mediated by a protein complex known as the divisome. Many protein-protein interactions in the divisome have been characterized. In this report, we analyse the role of the PASTA (Penicillin-binding protein And Serine Threonine kinase Associated) domains of Bacillus subtilis PBP2B. PBP2B itself is essential and cannot be deleted, but removing the PBP2B PASTA domains results in impaired cell division and a heat-sensitive phenotype. This resembles the deletion of divIB, a known interaction partner of PBP2B. Bacterial two-hybrid and co-immunoprecipitation analyses show that the interaction between PBP2B and DivIB is weakened when the PBP2B PASTA domains are removed. Combined, our results show that the PBP2B PASTA domains are required to strengthen the interaction between PBP2B and DivIB.
Collapse
Affiliation(s)
- Danae Morales Angeles
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
- Present address: Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 Ås, Norway
| | - Alicia Macia-Valero
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Laura C. Bohorquez
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
- Present address: BluSense Diagnostics ApS, Carrera 63 100-49, Bogota 111121, Colombia
| | - Dirk-Jan Scheffers
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| |
Collapse
|
13
|
Sexton DL, Herlihey FA, Brott AS, Crisante DA, Shepherdson E, Clarke AJ, Elliot MA. Roles of LysM and LytM domains in resuscitation-promoting factor (Rpf) activity and Rpf-mediated peptidoglycan cleavage and dormant spore reactivation. J Biol Chem 2020; 295:9171-9182. [PMID: 32434927 PMCID: PMC7335776 DOI: 10.1074/jbc.ra120.013994] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/15/2020] [Indexed: 11/06/2022] Open
Abstract
Bacterial dormancy can take many forms, including formation of Bacillus endospores, Streptomyces exospores, and metabolically latent Mycobacterium cells. In the actinobacteria, including the streptomycetes and mycobacteria, the rapid resuscitation from a dormant state requires the activities of a family of cell-wall lytic enzymes called resuscitation-promoting factors (Rpfs). Whether Rpf activity promotes resuscitation by generating peptidoglycan fragments (muropeptides) that function as signaling molecules for spore germination or by simply remodeling the dormant cell wall has been the subject of much debate. Here, to address this question, we used mutagenesis and peptidoglycan binding and cleavage assays to first gain broader insight into the biochemical function of diverse Rpf enzymes. We show that their LysM and LytM domains enhance Rpf enzyme activity; their LytM domain and, in some cases their LysM domain, also promoted peptidoglycan binding. We further demonstrate that the Rpfs function as endo-acting lytic transglycosylases, cleaving within the peptidoglycan backbone. We also found that unlike in other systems, Rpf activity in the streptomycetes is not correlated with peptidoglycan-responsive Ser/Thr kinases for cell signaling, and the germination of rpf mutant strains could not be stimulated by the addition of known germinants. Collectively, these results suggest that in Streptomyces, Rpfs have a structural rather than signaling function during spore germination, and that in the actinobacteria, any signaling function associated with spore resuscitation requires the activity of additional yet to be identified enzymes.
Collapse
Affiliation(s)
- Danielle L Sexton
- Michael G. DeGroote Institute for Infectious Disease Research and Department of Biology, McMaster University, Hamilton, Canada
| | - Francesca A Herlihey
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - Ashley S Brott
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - David A Crisante
- Michael G. DeGroote Institute for Infectious Disease Research and Department of Biology, McMaster University, Hamilton, Canada
| | - Evan Shepherdson
- Michael G. DeGroote Institute for Infectious Disease Research and Department of Biology, McMaster University, Hamilton, Canada
| | - Anthony J Clarke
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - Marie A Elliot
- Michael G. DeGroote Institute for Infectious Disease Research and Department of Biology, McMaster University, Hamilton, Canada.
| |
Collapse
|
14
|
Kaur G, Burroughs AM, Iyer LM, Aravind L. Highly regulated, diversifying NTP-dependent biological conflict systems with implications for the emergence of multicellularity. eLife 2020; 9:e52696. [PMID: 32101166 PMCID: PMC7159879 DOI: 10.7554/elife.52696] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 02/25/2020] [Indexed: 12/12/2022] Open
Abstract
Social cellular aggregation or multicellular organization pose increased risk of transmission of infections through the system upon infection of a single cell. The generality of the evolutionary responses to this outside of Metazoa remains unclear. We report the discovery of several thematically unified, remarkable biological conflict systems preponderantly present in multicellular prokaryotes. These combine thresholding mechanisms utilizing NTPase chaperones (the MoxR-vWA couple), GTPases and proteolytic cascades with hypervariable effectors, which vary either by using a reverse transcriptase-dependent diversity-generating system or through a system of acquisition of diverse protein modules, typically in inactive form, from various cellular subsystems. Conciliant lines of evidence indicate their deployment against invasive entities, like viruses, to limit their spread in multicellular/social contexts via physical containment, dominant-negative interactions or apoptosis. These findings argue for both a similar operational 'grammar' and shared protein domains in the sensing and limiting of infections during the multiple emergences of multicellularity.
Collapse
Affiliation(s)
- Gurmeet Kaur
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - A Maxwell Burroughs
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - Lakshminarayan M Iyer
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - L Aravind
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaUnited States
| |
Collapse
|
15
|
Muropeptides Stimulate Growth Resumption from Stationary Phase in Escherichia coli. Sci Rep 2019; 9:18043. [PMID: 31792329 PMCID: PMC6888817 DOI: 10.1038/s41598-019-54646-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 11/18/2019] [Indexed: 12/19/2022] Open
Abstract
When nutrients run out, bacteria enter a dormant metabolic state. This low or undetectable metabolic activity helps bacteria to preserve their scant reserves for the future needs, yet it also diminishes their ability to scan the environment for new growth-promoting substrates. However, neighboring microbial growth is a reliable indicator of a favorable environment and can thus serve as a cue for exiting dormancy. Here we report that for Escherichia coli and Pseudomonas aeruginosa this cue is provided by the basic peptidoglycan unit (i.e. muropeptide). We show that several forms of muropeptides from a variety of bacterial species can stimulate growth resumption of dormant cells and the sugar – peptide bond is crucial for this activity. These results, together with previous research that identifies muropeptides as a germination signal for bacterial spores, and their detection by mammalian immune cells, show that muropeptides are a universal cue for bacterial growth.
Collapse
|
16
|
Abstract
Over the past decade the number and variety of protein post-translational modifications that have been detected and characterized in bacteria have rapidly increased. Most post-translational protein modifications occur in a relatively low number of bacterial proteins in comparison with eukaryotic proteins, and most of the modified proteins carry low, substoichiometric levels of modification; therefore, their structural and functional analysis is particularly challenging. The number of modifying enzymes differs greatly among bacterial species, and the extent of the modified proteome strongly depends on environmental conditions. Nevertheless, evidence is rapidly accumulating that protein post-translational modifications have vital roles in various cellular processes such as protein synthesis and turnover, nitrogen metabolism, the cell cycle, dormancy, sporulation, spore germination, persistence and virulence. Further research of protein post-translational modifications will fill current gaps in the understanding of bacterial physiology and open new avenues for treatment of infectious diseases.
Collapse
|
17
|
Gordhan BG, Peters J, Kana BD. Application of model systems to study adaptive responses of Mycobacterium tuberculosis during infection and disease. ADVANCES IN APPLIED MICROBIOLOGY 2019; 108:115-161. [PMID: 31495404 DOI: 10.1016/bs.aambs.2019.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Tuberculosis (TB) claims more human lives than any other infectious organism. The lethal synergy between TB-HIV infection and the rapid emergence of drug resistant strains has created a global public health threat that requires urgent attention. Mycobacterium tuberculosis, the causative agent of TB is an exquisitely well-adapted human pathogen, displaying the ability to promptly remodel metabolism when encountering stressful environments during pathogenesis. A careful study of the mechanisms that enable this adaptation will enhance the understanding of key aspects related to the microbiology of TB disease. However, these efforts require microbiological model systems that mimic host conditions in the laboratory. Herein, we describe several in vitro model systems that generate non-replicating and differentially culturable mycobacteria. The changes that occur in the metabolism of M. tuberculosis in some of these models and how these relate to those reported for human TB disease are discussed. We describe mechanisms that tubercle bacteria use to resuscitate from these non-replicating conditions, together with phenotypic heterogeneity in terms of culturabiliy of M. tuberculosis in sputum. Transcriptional changes in M. tuberculosis that allow for adaptation of the organism to the lung environment are also summarized. Finally, given the emerging importance of the microbiome in various infectious diseases, we provide a description of how the lung and gut microbiome affect susceptibility to TB infection and response to treatment. Consideration of these collective aspects will enhance the understanding of basic metabolism, physiology, drug tolerance and persistence in M. tuberculosis to enable development of new therapeutic interventions.
Collapse
Affiliation(s)
- Bhavna Gowan Gordhan
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Julian Peters
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa
| | - Bavesh Davandra Kana
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, Johannesburg, South Africa.
| |
Collapse
|
18
|
Park EJ, Kwon YM, Lee JW, Kang HY, Oh JI. Dual control of RegX3 transcriptional activity by SenX3 and PknB. J Biol Chem 2019; 294:11023-11034. [PMID: 31160336 DOI: 10.1074/jbc.ra119.008232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/30/2019] [Indexed: 01/08/2023] Open
Abstract
The mycobacterial SenX3-RegX3 two-component system consists of the SenX3 sensor histidine kinase and its cognate RegX3 response regulator. This system is a phosphorelay-based regulatory system involved in sensing environmental Pi levels and induction of genes required for Pi acquisition under Pi-limiting conditions. Here we demonstrate that overexpression of the kinase domain of Mycobacterium tuberculosis PknB (PknB-KDMtb) inhibits the transcriptional activity of RegX3 of both M. tuberculosis and Mycobacterium smegmatis (RegX3Mtb and RegX3Ms, respectively). Mass spectrometry results, along with those of in vitro phosphorylation and complementation analyses, revealed that PknB kinase activity inhibits the transcriptional activity of RegX3Mtb through phosphorylation events at Thr-100, Thr-191, and Thr-217. Electrophoretic mobility shift assays disclosed that phosphorylation of Thr-191 and Thr-217 abolishes the DNA-binding ability of RegX3Mtb and that Thr-100 phosphorylation likely prevents RegX3Mtb from being activated through conformational changes induced by SenX3-mediated phosphorylation. We propose that the convergence of the PknB and SenX3-RegX3 signaling pathways might enable mycobacteria to integrate environmental Pi signals with the cellular replication state to adjust gene expression in response to Pi availability.
Collapse
Affiliation(s)
- Eun-Jin Park
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Yu-Mi Kwon
- Biomedical Research Institute, Center for Theragnosis, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea, and; Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Jin-Won Lee
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Ho-Young Kang
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Jeong-Il Oh
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea,.
| |
Collapse
|
19
|
Novel and Improved Crystal Structures of H. influenzae, E. coli and P. aeruginosa Penicillin-Binding Protein 3 (PBP3) and N. gonorrhoeae PBP2: Toward a Better Understanding of β-Lactam Target-Mediated Resistance. J Mol Biol 2019; 431:3501-3519. [PMID: 31301409 DOI: 10.1016/j.jmb.2019.07.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 07/02/2019] [Accepted: 07/02/2019] [Indexed: 01/26/2023]
Abstract
Even with the emergence of antibiotic resistance, penicillin and the wider family of β-lactams have remained the single most important family of antibiotics. The periplasmic/extra-cytoplasmic targets of penicillin are a family of enzymes with a highly conserved catalytic activity involved in the final stage of bacterial cell wall (peptidoglycan) biosynthesis. Named after their ability to bind penicillin, rather than their catalytic activity, these key targets are called penicillin-binding proteins (PBPs). Resistance is predominantly mediated by reducing the target drug concentration via β-lactamases; however, naturally transformable bacteria have also acquired target-mediated resistance by inter-species recombination. Here we focus on structural based interpretations of amino acid alterations associated with the emergence of resistance within clinical isolates and include new PBP3 structures along with new, and improved, PBP-β-lactam co-structures.
Collapse
|
20
|
Bellinzoni M, Wehenkel AM, Durán R, Alzari PM. Novel mechanistic insights into physiological signaling pathways mediated by mycobacterial Ser/Thr protein kinases. Microbes Infect 2019; 21:222-229. [PMID: 31254628 DOI: 10.1016/j.micinf.2019.06.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 12/11/2022]
Abstract
Protein phosphorylation is known to be one of the keystones of signal sensing and transduction in all living organisms. Once thought to be essentially confined to the eukaryotic kingdoms, reversible phosphorylation on serine, threonine and tyrosine residues, has now been shown to play a major role in many prokaryotes, where the number of Ser/Thr protein kinases (STPKs) equals or even exceeds that of two component systems. Mycobacterium tuberculosis, the etiological agent of tuberculosis, is one of the most studied organisms for the role of STPK-mediated signaling in bacteria. Driven by the interest and tractability of these enzymes as potential therapeutic targets, extensive studies revealed the remarkable conservation of protein kinases and their cognate phosphatases across evolution, and their involvement in bacterial physiology and virulence. Here, we present an overview of the current knowledge of mycobacterial STPKs structures and kinase activation mechanisms, and we then focus on PknB and PknG, two well-characterized STPKs that are essential for the intracellular survival of the bacillus. We summarize the mechanistic evidence that links PknB to the regulation of peptidoglycan synthesis in cell division and morphogenesis, and the major findings that establishes PknG as a master regulator of central carbon and nitrogen metabolism. Two decades after the discovery of STPKs in M. tuberculosis, the emerging landscape of O-phosphosignaling is starting to unveil how eukaryotic-like kinases can be engaged in unique, non-eukaryotic-like, signaling mechanisms in mycobacteria.
Collapse
Affiliation(s)
- Marco Bellinzoni
- Unit of Structural Microbiology, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR 3528 & Université Paris Diderot, 25 rue du Docteur Roux, 75724 Paris cedex 15, France
| | - Anne Marie Wehenkel
- Unit of Structural Microbiology, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR 3528 & Université Paris Diderot, 25 rue du Docteur Roux, 75724 Paris cedex 15, France
| | - Rosario Durán
- Unidad de Bioquímica y Proteómica Analíticas, Institut Pasteur de Montevideo, Instituto de Investigaciones Biológicas Clemente Estable, Mataojo 2020, Montevideo 11400, Uruguay
| | - Pedro M Alzari
- Unit of Structural Microbiology, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR 3528 & Université Paris Diderot, 25 rue du Docteur Roux, 75724 Paris cedex 15, France.
| |
Collapse
|
21
|
Mycobacterial phosphatase PstP regulates global serine threonine phosphorylation and cell division. Sci Rep 2019; 9:8337. [PMID: 31171861 PMCID: PMC6554272 DOI: 10.1038/s41598-019-44841-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/24/2019] [Indexed: 12/28/2022] Open
Abstract
Protein phosphatase PstP is conserved throughout the Actinobacteria in a genetic locus related to cell wall synthesis and cell division. In many Actinobacteria it is the sole annotated serine threonine protein phosphatase to counter the activity of multiple serine threonine protein kinases. We used transcriptional knockdown, electron microscopy and comparative phosphoproteomics to investigate the putative dual functions of PstP as a specific regulator of cell division and as a global regulator of protein phosphorylation. Comparative phosphoproteomics in the early stages of PstP depletion showed hyperphosphorylation of protein kinases and their substrates, confirming PstP as a negative regulator of kinase activity and global serine and threonine phosphorylation. Analysis of the 838 phosphorylation sites that changed significantly, suggested that PstP may regulate diverse phosphoproteins, preferentially at phosphothreonine near acidic residues, near the protein termini, and within membrane associated proteins. Increased phosphorylation of the activation loop of protein kinase B (PknB) and of the essential PknB substrate CwlM offer possible explanations for the requirement for pstP for growth and for cell wall defects when PstP was depleted.
Collapse
|
22
|
Vollmer W, Massidda O, Tomasz A. The Cell Wall of Streptococcus pneumoniae. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0018-2018. [PMID: 31172911 PMCID: PMC11026078 DOI: 10.1128/microbiolspec.gpp3-0018-2018] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Indexed: 12/13/2022] Open
Abstract
Streptococcus pneumoniae has a complex cell wall that plays key roles in cell shape maintenance, growth and cell division, and interactions with components of the human host. The peptidoglycan has a heterogeneous composition with more than 50 subunits (muropeptides)-products of several peptidoglycan-modifying enzymes. The amidation of glutamate residues in the stem peptide is needed for efficient peptide cross-linking, and peptides with a dipeptide branch prevail in some beta-lactam-resistant strains. The glycan strands are modified by deacetylation of N-acetylglucosamine residues and O-acetylation of N-acetylmuramic acid residues, and both modifications contribute to pneumococcal resistance to lysozyme. The glycan strands carry covalently attached wall teichoic acid and capsular polysaccharide. Pneumococci are unique in that the wall teichoic acid and lipoteichoic acid contain the same unusually complex repeating units decorated with phosphoryl choline residues, which anchor the choline-binding proteins. The structures of lipoteichoic acid and the attachment site of wall teichoic acid to peptidoglycan have recently been revised. During growth, pneumococci assemble their cell walls at midcell in coordinated rounds of cell elongation and division, leading to the typical ovococcal cell shape. Cell wall growth depends on the cytoskeletal FtsA and FtsZ proteins and is regulated by several morphogenesis proteins that also show patterns of dynamic localization at midcell. Some of the key regulators are phosphorylated by StkP and dephosphorylated by PhpP to facilitate robust selection of the division site and plane and to maintain cell shape.
Collapse
Affiliation(s)
- Waldemar Vollmer
- Institute for Cell and Molecular Biosciences, The Centre for Bacterial Cell Biology, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Orietta Massidda
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | | |
Collapse
|
23
|
Li X, Lv X, Lin Y, Zhen J, Ruan C, Duan W, Li Y, Xie J. Role of two-component regulatory systems in intracellular survival of Mycobacterium tuberculosis. J Cell Biochem 2019; 120:12197-12207. [PMID: 31026098 DOI: 10.1002/jcb.28792] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/11/2019] [Accepted: 01/14/2019] [Indexed: 11/06/2022]
Abstract
The typical two-component regulatory systems (TCSs), consisting of response regulator and histidine kinase, play a central role in survival of pathogenic bacteria under stress conditions such as nutrient starvation, hypoxia, and nitrosative stress. A total of 11 complete paired two-component regulatory systems have been found in Mycobacterium tuberculosis, including a few isolated kinase and regulatory genes. Increasing evidence has shown that TCSs are closely associated with multiple physiological process like intracellular persistence, pathogenicity, and metabolism. This review gives the two-component signal transduction systems in M. tuberculosis and their signal transduction roles in adaption to the environment.
Collapse
Affiliation(s)
- Xue Li
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Xi Lv
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Yanping Lin
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Junfeng Zhen
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Cao Ruan
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Wei Duan
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Yue Li
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| | - Jianping Xie
- State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Institute of Modern Biopharmaceuticals, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, China
| |
Collapse
|
24
|
Bellinzoni M, Wehenkel AM, Durán R, Alzari PM. Novel mechanistic insights into physiological signaling pathways mediated by mycobacterial Ser/Thr protein kinases. Genes Immun 2019; 20:383-393. [DOI: 10.1038/s41435-019-0069-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 12/16/2022]
|
25
|
Irazoki O, Hernandez SB, Cava F. Peptidoglycan Muropeptides: Release, Perception, and Functions as Signaling Molecules. Front Microbiol 2019; 10:500. [PMID: 30984120 PMCID: PMC6448482 DOI: 10.3389/fmicb.2019.00500] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 02/27/2019] [Indexed: 12/12/2022] Open
Abstract
Peptidoglycan (PG) is an essential molecule for the survival of bacteria, and thus, its biosynthesis and remodeling have always been in the spotlight when it comes to the development of antibiotics. The peptidoglycan polymer provides a protective function in bacteria, but at the same time is continuously subjected to editing activities that in some cases lead to the release of peptidoglycan fragments (i.e., muropeptides) to the environment. Several soluble muropeptides have been reported to work as signaling molecules. In this review, we summarize the mechanisms involved in muropeptide release (PG breakdown and PG recycling) and describe the known PG-receptor proteins responsible for PG sensing. Furthermore, we overview the role of muropeptides as signaling molecules, focusing on the microbial responses and their functions in the host beyond their immunostimulatory activity.
Collapse
Affiliation(s)
| | | | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| |
Collapse
|
26
|
Kaur P, Rausch M, Malakar B, Watson U, Damle NP, Chawla Y, Srinivasan S, Sharma K, Schneider T, Jhingan GD, Saini D, Mohanty D, Grein F, Nandicoori VK. LipidII interaction with specific residues of Mycobacterium tuberculosis PknB extracytoplasmic domain governs its optimal activation. Nat Commun 2019; 10:1231. [PMID: 30874556 PMCID: PMC6428115 DOI: 10.1038/s41467-019-09223-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 02/28/2019] [Indexed: 02/08/2023] Open
Abstract
The Mycobacterium tuberculosis kinase PknB is essential for growth and survival of the pathogen in vitro and in vivo. Here we report the results of our efforts to elucidate the mechanism of regulation of PknB activity. The specific residues in the PknB extracytoplasmic domain that are essential for ligand interaction and survival of the bacterium are identified. The extracytoplasmic domain interacts with mDAP-containing LipidII, and this is abolished upon mutation of the ligand-interacting residues. Abrogation of ligand-binding or sequestration of the ligand leads to aberrant localization of PknB. Contrary to the prevailing hypothesis, abrogation of ligand-binding is linked to activation loop hyperphosphorylation, and indiscriminate hyperphosphorylation of PknB substrates as well as other proteins, ultimately causing loss of homeostasis and cell death. We propose that the ligand-kinase interaction directs the appropriate localization of the kinase, coupled to stringently controlled activation of PknB, and consequently the downstream processes thereof. The Mycobacterium tuberculosis kinase PknB regulates essential cell functions via interactions with muropeptides. Here the authors identify interaction sites in the extracytoplasmic PASTA domain and show that abrogation of ligand binding leads to a hyper-activated kinase, causing loss of homeostasis and cell death.
Collapse
Affiliation(s)
- Prabhjot Kaur
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Marvin Rausch
- Institute for Pharmaceutical Microbiology, University Hospital Bonn, University of Bonn, Bonn, 53105, Germany.,German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, 53105, Germany
| | - Basanti Malakar
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Uchenna Watson
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bengaluru, 560012, India
| | - Nikhil P Damle
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India.,BIOSS, Center for Biological Signaling Studies, University of Freiburg, Freiburg, 79104, Germany
| | - Yogesh Chawla
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India.,Department of Microbiology and Immunology, Weill Cornell Medical College, New York, 10065, NY, USA
| | - Sandhya Srinivasan
- Vproteomics, Valerian Chem Private Limited, Green Park Main, New Delhi, 110016, India
| | - Kanika Sharma
- Vproteomics, Valerian Chem Private Limited, Green Park Main, New Delhi, 110016, India
| | - Tanja Schneider
- Institute for Pharmaceutical Microbiology, University Hospital Bonn, University of Bonn, Bonn, 53105, Germany.,German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, 53105, Germany
| | - Gagan Deep Jhingan
- Vproteomics, Valerian Chem Private Limited, Green Park Main, New Delhi, 110016, India
| | - Deepak Saini
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bengaluru, 560012, India
| | - Debasisa Mohanty
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Fabian Grein
- Institute for Pharmaceutical Microbiology, University Hospital Bonn, University of Bonn, Bonn, 53105, Germany.,German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, 53105, Germany
| | | |
Collapse
|
27
|
Shi L, Cavagnino A, Rabefiraisana JL, Lazar N, Li de la Sierra-Gallay I, Ochsenbein F, Valerio-Lepiniec M, Urvoas A, Minard P, Mijakovic I, Nessler S. Structural Analysis of the Hanks-Type Protein Kinase YabT From Bacillus subtilis Provides New Insights in its DNA-Dependent Activation. Front Microbiol 2019; 9:3014. [PMID: 30671027 PMCID: PMC6333020 DOI: 10.3389/fmicb.2018.03014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/21/2018] [Indexed: 12/19/2022] Open
Abstract
YabT is a serine/threonine kinase of the Hanks family from Bacillus subtilis, which lacks the canonical extracellular signal receptor domain but is anchored to the membrane through a C-terminal transmembrane helix. A previous study demonstrated that a basic juxtamembrane region corresponds to a DNA-binding motif essential for the activation of YabT trans-autophosphorylation. YabT is expressed during spore development and localizes to the asymmetric septum where it specifically phosphorylates essential proteins involved in genome maintenance, such as RecA, SsbA, and YabA. YabT has also been shown to phosphorylate proteins involved in protein synthesis, such as AbrB and Ef-Tu, suggesting a possible regulatory role in the progressive metabolic quiescence of the forespore. Finally, cross phosphorylations with other protein kinases implicate YabT in the regulation of numerous other cellular processes. Using an artificial protein scaffold as crystallization helper, we determined the first crystal structure of this DNA-dependent bacterial protein kinase. This allowed us to trap the active conformation of the kinase domain of YabT. Using NMR, we showed that the basic juxtamembrane region of YabT is disordered in the absence of DNA in solution, just like it is in the crystal, and that it is stabilized upon DNA binding. In comparison with its closest structural homolog, the mycobacterial kinase PknB allowed us to discuss the dimerization mode of YabT. Together with phosphorylation assays and DNA-binding experiments, this structural analysis helped us to gain new insights into the regulatory activation mechanism of YabT.
Collapse
Affiliation(s)
- Lei Shi
- Division of Systems and Synthetic Biology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Andrea Cavagnino
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Jean-Luc Rabefiraisana
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Noureddine Lazar
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Inès Li de la Sierra-Gallay
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Françoise Ochsenbein
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Marie Valerio-Lepiniec
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Agathe Urvoas
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Philippe Minard
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Ivan Mijakovic
- Division of Systems and Synthetic Biology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Sylvie Nessler
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| |
Collapse
|
28
|
Peterson E, Kaur P. Antibiotic Resistance Mechanisms in Bacteria: Relationships Between Resistance Determinants of Antibiotic Producers, Environmental Bacteria, and Clinical Pathogens. Front Microbiol 2018; 9:2928. [PMID: 30555448 PMCID: PMC6283892 DOI: 10.3389/fmicb.2018.02928] [Citation(s) in RCA: 424] [Impact Index Per Article: 70.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/14/2018] [Indexed: 11/13/2022] Open
Abstract
Emergence of antibiotic resistant pathogenic bacteria poses a serious public health challenge worldwide. However, antibiotic resistance genes are not confined to the clinic; instead they are widely prevalent in different bacterial populations in the environment. Therefore, to understand development of antibiotic resistance in pathogens, we need to consider important reservoirs of resistance genes, which may include determinants that confer self-resistance in antibiotic producing soil bacteria and genes encoding intrinsic resistance mechanisms present in all or most non-producer environmental bacteria. While the presence of resistance determinants in soil and environmental bacteria does not pose a threat to human health, their mobilization to new hosts and their expression under different contexts, for example their transfer to plasmids and integrons in pathogenic bacteria, can translate into a problem of huge proportions, as discussed in this review. Selective pressure brought about by human activities further results in enrichment of such determinants in bacterial populations. Thus, there is an urgent need to understand distribution of resistance determinants in bacterial populations, elucidate resistance mechanisms, and determine environmental factors that promote their dissemination. This comprehensive review describes the major known self-resistance mechanisms found in producer soil bacteria of the genus Streptomyces and explores the relationships between resistance determinants found in producer soil bacteria, non-producer environmental bacteria, and clinical isolates. Specific examples highlighting potential pathways by which pathogenic clinical isolates might acquire these resistance determinants from soil and environmental bacteria are also discussed. Overall, this article provides a conceptual framework for understanding the complexity of the problem of emergence of antibiotic resistance in the clinic. Availability of such knowledge will allow researchers to build models for dissemination of resistance genes and for developing interventions to prevent recruitment of additional or novel genes into pathogens.
Collapse
Affiliation(s)
- Elizabeth Peterson
- Department of Biology, Georgia State University, Atlanta, GA, United States
| | - Parjit Kaur
- Department of Biology, Georgia State University, Atlanta, GA, United States
| |
Collapse
|
29
|
Turapov O, Forti F, Kadhim B, Ghisotti D, Sassine J, Straatman-Iwanowska A, Bottrill AR, Moynihan PJ, Wallis R, Barthe P, Cohen-Gonsaud M, Ajuh P, Vollmer W, Mukamolova GV. Two Faces of CwlM, an Essential PknB Substrate, in Mycobacterium tuberculosis. Cell Rep 2018; 25:57-67.e5. [PMID: 30282038 PMCID: PMC6180346 DOI: 10.1016/j.celrep.2018.09.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/11/2018] [Accepted: 08/31/2018] [Indexed: 11/26/2022] Open
Abstract
Tuberculosis claims >1 million lives annually, and its causative agent Mycobacterium tuberculosis is a highly successful pathogen. Protein kinase B (PknB) is reported to be critical for mycobacterial growth. Here, we demonstrate that PknB-depleted M. tuberculosis can replicate normally and can synthesize peptidoglycan in an osmoprotective medium. Comparative phosphoproteomics of PknB-producing and PknB-depleted mycobacteria identify CwlM, an essential regulator of peptidoglycan synthesis, as a major PknB substrate. Our complementation studies of a cwlM mutant of M. tuberculosis support CwlM phosphorylation as a likely molecular basis for PknB being essential for mycobacterial growth. We demonstrate that growing mycobacteria produce two forms of CwlM: a non-phosphorylated membrane-associated form and a PknB-phosphorylated cytoplasmic form. Furthermore, we show that the partner proteins for the phosphorylated and non-phosphorylated forms of CwlM are FhaA, a fork head-associated domain protein, and MurJ, a proposed lipid II flippase, respectively. From our results, we propose a model in which CwlM potentially regulates both the biosynthesis of peptidoglycan precursors and their transport across the cytoplasmic membrane.
Collapse
Affiliation(s)
- Obolbek Turapov
- Leicester Tuberculosis Research Group, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, UK
| | - Francesca Forti
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Baleegh Kadhim
- Leicester Tuberculosis Research Group, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, UK; Biology Department, College of Science, University of Al-Qadisiyah, Al-Diwaniyah 58002, Iraq
| | - Daniela Ghisotti
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Jad Sassine
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Anna Straatman-Iwanowska
- Electron Microscopy Facility, Core Biotechnology Services, University of Leicester, Leicester LE1 7RH, UK
| | - Andrew R Bottrill
- Protein Nucleic Acid Laboratory, University of Leicester, Leicester LE1 7RH, UK
| | - Patrick J Moynihan
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Russell Wallis
- Leicester Tuberculosis Research Group, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, UK; The Leicester Institute of Structural and Chemical Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7HB, UK
| | - Philippe Barthe
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, Montpellier 34090, France
| | - Martin Cohen-Gonsaud
- Centre de Biochimie Structurale, CNRS, INSERM, University of Montpellier, Montpellier 34090, France
| | - Paul Ajuh
- Gemini Biosciences, Liverpool Science Park, Liverpool L3 5TF, UK
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Galina V Mukamolova
- Leicester Tuberculosis Research Group, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, UK.
| |
Collapse
|
30
|
Janczarek M, Vinardell JM, Lipa P, Karaś M. Hanks-Type Serine/Threonine Protein Kinases and Phosphatases in Bacteria: Roles in Signaling and Adaptation to Various Environments. Int J Mol Sci 2018; 19:ijms19102872. [PMID: 30248937 PMCID: PMC6213207 DOI: 10.3390/ijms19102872] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/17/2018] [Accepted: 09/19/2018] [Indexed: 12/19/2022] Open
Abstract
Reversible phosphorylation is a key mechanism that regulates many cellular processes in prokaryotes and eukaryotes. In prokaryotes, signal transduction includes two-component signaling systems, which involve a membrane sensor histidine kinase and a cognate DNA-binding response regulator. Several recent studies indicate that alternative regulatory pathways controlled by Hanks-type serine/threonine kinases (STKs) and serine/threonine phosphatases (STPs) also play an essential role in regulation of many different processes in bacteria, such as growth and cell division, cell wall biosynthesis, sporulation, biofilm formation, stress response, metabolic and developmental processes, as well as interactions (either pathogenic or symbiotic) with higher host organisms. Since these enzymes are not DNA-binding proteins, they exert the regulatory role via post-translational modifications of their protein targets. In this review, we summarize the current knowledge of STKs and STPs, and discuss how these enzymes mediate gene expression in prokaryotes. Many studies indicate that regulatory systems based on Hanks-type STKs and STPs play an essential role in the regulation of various cellular processes, by reversibly phosphorylating many protein targets, among them several regulatory proteins of other signaling cascades. These data show high complexity of bacterial regulatory network, in which the crosstalk between STK/STP signaling enzymes, components of TCSs, and the translational machinery occurs. In this regulation, the STK/STP systems have been proved to play important roles.
Collapse
Affiliation(s)
- Monika Janczarek
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| | - José-María Vinardell
- Department of Microbiology, Faculty of Biology, University of Sevilla, Avda. Reina Mercedes 6, 41012 Sevilla, Spain.
| | - Paulina Lipa
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| | - Magdalena Karaś
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| |
Collapse
|
31
|
Raghavendra T, Patil S, Mukherjee R. Peptidoglycan in Mycobacteria: chemistry, biology and intervention. Glycoconj J 2018; 35:421-432. [DOI: 10.1007/s10719-018-9842-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/20/2018] [Accepted: 09/05/2018] [Indexed: 01/07/2023]
|
32
|
Huang YY, Sun YH, Huang N, Liu XX, Yan J, Sun AH. Sublethal β-lactam antibiotics induce PhpP phosphatase expression and StkP kinase phosphorylation in PBP-independent β-lactam antibiotic resistance of Streptococcus pneumoniae. Biochem Biophys Res Commun 2018; 503:2000-2008. [PMID: 30135012 DOI: 10.1016/j.bbrc.2018.07.148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 07/30/2018] [Indexed: 12/16/2022]
Abstract
StkP and PhpP of Streptococcus pneumoniae have been confirmed to compose a signaling couple, in which the former is a serine/threonine (Ser/Thr) kinase while the latter was annotated as a phosphotase. StkP has been reported to be involved in penicillin-binding protein (PBP)-independent penicillin resistance of S. pneumoniae. However, the enzymatic characterization of PhpP and the role of PhpP in StkP-PhpP couple remain poorly understood. Here we showed that 1/4 minimal inhibitory concentration (MIC) of penicillin (PCN) or cefotaxime (CTX), the representatives of β-lactam antibiotics, could induce the expression of stkP and phpP genes and phosphorylation of StkP in PCN/CTX-sensitive strain ATCC6306 and three isolates of S. pneumoniae (MICs: 0.02-0.5 μg/ml). The product of phpP gene hydrolyzed PP2C type Ser/Thr phosphotase-specific RRA (pT)VA phosphopeptide substrate with the Km and Kcat values of 277.35 μmoL/L and 0.71 S-1, and the hydrolytic activity was blocked by sodium fluoride, a PP2C type Ser/Thr phosphatase inhibitor. The phosphorylation levels of StkP in the four phpP gene-knockout (ΔphpP) mutants were significantly higher than that in the wild-type strains. In particular, the MICs of PCN and CTX against the ΔphpP mutants were significantly elevated as 4-16 μg/ml. Therefore, our findings confirmed that sublethal PCN and CTX act as environmental inducers to cause the increase of phpP and stkP gene expression and StkP phosphorylation. PhpP is a PP2C type Ser/Thr protein phosphatase responsible for dephosphorylation of StkP. Knockout of the phpP gene results in a high level of StkP phosphorylation and PBP-independent PCN/CTX resistance of S. pneumoniae.
Collapse
Affiliation(s)
- Yan-Ying Huang
- Faculty of Basic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, 310053, PR China; Department of Pathology, Hangzhou Red Cross Hospital, Hangzhou, Zhejiang, 310003, PR China.
| | - Yan-Hong Sun
- Department of Laboratory Medicine, The Children's Hospital Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310052, PR China.
| | - Nan Huang
- College of Medical Technology, Zhang Chinese Medical University, Hangzhou, Zhejiang, 310053, PR China.
| | - Xiao-Xiang Liu
- Faculty of Basic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, 310053, PR China.
| | - Jie Yan
- Division of Basic Medical Microbiology, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310003, PR China; Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, PR China.
| | - Ai-Hua Sun
- Faculty of Basic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, 310053, PR China.
| |
Collapse
|
33
|
Calvanese L, Falcigno L, Squeglia F, Berisio R, D’Auria G. PASTA sequence composition is a predictive tool for protein class identification. Amino Acids 2018; 50:1441-1450. [DOI: 10.1007/s00726-018-2621-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 07/13/2018] [Indexed: 12/18/2022]
|
34
|
Khan MZ, Kaur P, Nandicoori VK. Targeting the messengers: Serine/threonine protein kinases as potential targets for antimycobacterial drug development. IUBMB Life 2018; 70:889-904. [DOI: 10.1002/iub.1871] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 04/22/2018] [Indexed: 02/03/2023]
Affiliation(s)
- Mehak Zahoor Khan
- National Institute of Immunology, Aruna Asaf Ali Marg; New Delhi India
| | - Prabhjot Kaur
- National Institute of Immunology, Aruna Asaf Ali Marg; New Delhi India
| | | |
Collapse
|
35
|
Piñas GE, Reinoso-Vizcaino NM, Yandar Barahona NY, Cortes PR, Duran R, Badapanda C, Rathore A, Bichara DR, Cian MB, Olivero NB, Perez DR, Echenique J. Crosstalk between the serine/threonine kinase StkP and the response regulator ComE controls the stress response and intracellular survival of Streptococcus pneumoniae. PLoS Pathog 2018; 14:e1007118. [PMID: 29883472 PMCID: PMC6010298 DOI: 10.1371/journal.ppat.1007118] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 06/20/2018] [Accepted: 05/23/2018] [Indexed: 11/30/2022] Open
Abstract
Streptococcus pneumoniae is an opportunistic human bacterial pathogen that usually colonizes the upper respiratory tract, but the invasion and survival mechanism in respiratory epithelial cells remains elusive. Previously, we described that acidic stress-induced lysis (ASIL) and intracellular survival are controlled by ComE through a yet unknown activation mechanism under acidic conditions, which is independent of the ComD histidine kinase that activates this response regulator for competence development at pH 7.8. Here, we demonstrate that the serine/threonine kinase StkP is essential for ASIL, and show that StkP phosphorylates ComE at Thr128. Molecular dynamic simulations predicted that Thr128-phosphorylation induces conformational changes on ComE’s DNA-binding domain. Using nonphosphorylatable (ComET128A) and phosphomimetic (ComET128E) proteins, we confirmed that Thr128-phosphorylation increased the DNA-binding affinity of ComE. The non-phosphorylated form of ComE interacted more strongly with StkP than the phosphomimetic form at acidic pH, suggesting that pH facilitated crosstalk. To identify the ComE-regulated genes under acidic conditions, a comparative transcriptomic analysis was performed between the comET128A and wt strains, and differential expression of 104 genes involved in different cellular processes was detected, suggesting that the StkP/ComE pathway induced global changes in response to acidic stress. In the comET128A mutant, the repression of spxB and sodA correlated with decreased H2O2 production, whereas the reduced expression of murN correlated with an increased resistance to cell wall antibiotic-induced lysis, compatible with cell wall alterations. In the comET128A mutant, ASIL was blocked and acid tolerance response was higher compared to the wt strain. These phenotypes, accompanied with low H2O2 production, are likely responsible for the increased survival in pneumocytes of the comET128A mutant. We propose that the StkP/ComE pathway controls the stress response, thus affecting the intracellular survival of S. pneumoniae in pneumocytes, one of the first barriers that this pathogen must cross to establish an infection. Streptococcus pneumoniae is a major human pathogen and is the causal agent of otitis (media) and sinusitis. It is also responsible for severe infections such as bacteremia, pneumonia, and meningitis, associated with 2 million annual deaths. Although this bacterium is part of the human nasopharynx commensal microbiota, it can become a pathogen and cross the epithelial cell barrier to establishing infections of varying intensity. Although S. pneumoniae is considered to be a typical extracellular pathogen, transient intracellular life forms have been found in eukaryotic cells, suggesting a putative survival mechanism. Here, we report that the serine-threonine kinase StkP was able to phosphorylate the response regulator ComE to control different cellular processes in response to environmental stress. Moreover, the phosphorylation of ComE on Thr128, and the consequent conformational and functional changes resulting from this event, extended the current knowledge of molecular activation mechanisms of response regulators. In this report, we provide evidence for the regulatory control exerted by the StkP/ComE pathway on acid-induced autolysis (associated with pneumolysin release), the acid tolerance response, and H2O2 production to modulate tissue damage and intracellular survival, which are ultimately linked to pneumococcal pathogenesis.
Collapse
Affiliation(s)
- Germán E. Piñas
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
| | - Nicolás M. Reinoso-Vizcaino
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nubia Y. Yandar Barahona
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paulo R. Cortes
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Rosario Duran
- Instituto Pasteur de Montevideo and Instituto de Investigaciones Biológicas Clemente Estable, Unidad de Bioquímica y Proteómica Analíticas, Montevideo, Uruguay
| | | | - Ankita Rathore
- Bioinformatics Division, Xcelris Lab Limited, Ahmedabad, India
| | | | - Melina B. Cian
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nadia B. Olivero
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Daniel R. Perez
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America
| | - José Echenique
- Departamento de Bioquímica Clínica—CIBICI (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- * E-mail:
| |
Collapse
|
36
|
Zheng W, Cai X, Li S, Li Z. Autophosphorylation Mechanism of the Ser/Thr Kinase Stk1 From Staphylococcus aureus. Front Microbiol 2018; 9:758. [PMID: 29731745 PMCID: PMC5920020 DOI: 10.3389/fmicb.2018.00758] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 04/04/2018] [Indexed: 01/26/2023] Open
Abstract
The eukaryotic-like Ser/Thr kinase Stk1 is crucial for virulence, cell wall biosynthesis, and drug susceptibility in methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA). Importantly, MRSA lacking Stk1 become sensitive to β-lactam antibiotics, implying that Stk1 could be an alternative target for combination therapy. However, the autophosphorylation mechanism of Stk1 remains elusive. Using a phosphoproteomic study, we identified six in vivo phosphorylated activation loop residues (Ser159, Thr161, Ser162, Thr164, Thr166, and Thr172) of Stk1, which are also phosphorylated in vitro. We further showed that cis autophosphorylation of Thr172 in the GT/S motif is essential for self-activation and kinase activity of Stk1 kinase domain (Stk1-KD), whereas the trans autophosphorylation of other activation loop serines/threonines are required for the optimal kinase activity of Stk1-KD. Moreover, substitution of the activation loop serines/threonines impaired in vivo autophosphorylation activity of kinase variants, while T172A and T172D variants were unable to autophosphorylate in the cellular content, underlining the essential role of Thr172 for Stk1 activity in vivo. This study provides insights into molecular basis for regulation of Stk1 activity from S. aureus.
Collapse
Affiliation(s)
- Weihao Zheng
- School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Xiaodan Cai
- School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Shuiming Li
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Zigang Li
- School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| |
Collapse
|
37
|
Bernardo-García N, Mahasenan KV, Batuecas MT, Lee M, Hesek D, Petráčková D, Doubravová L, Branny P, Mobashery S, Hermoso JA. Allostery, Recognition of Nascent Peptidoglycan, and Cross-linking of the Cell Wall by the Essential Penicillin-Binding Protein 2x of Streptococcus pneumoniae. ACS Chem Biol 2018; 13:694-702. [PMID: 29357220 DOI: 10.1021/acschembio.7b00817] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Transpeptidases, members of the penicillin-binding protein (PBP) families, catalyze cross-linking of the bacterial cell wall. This transformation is critical for the survival of bacteria, and it is the target of inhibition by β-lactam antibiotics. We report herein our structural insights into catalysis by the essential PBP2x of Streptococcus pneumoniae by disclosing a total of four X-ray structures, two computational models based on the crystal structures, and molecular-dynamics simulations. The X-ray structures are for the apo PBP2x, the enzyme modified covalently in the active site by oxacillin (a penicillin antibiotic), the enzyme modified by oxacillin in the presence of a synthetic tetrasaccharide surrogate for the cell-wall peptidoglycan, and a noncovalent complex of cefepime (a cephalosporin antibiotic) bound to the active site. A prerequisite for catalysis by transpeptidases, including PBP2x, is the molecular recognition of nascent peptidoglycan strands, which harbor pentapeptide stems. We disclose that the recognition of nascent peptidoglycan by PBP2x takes place by complexation of one pentapeptide stem at an allosteric site located in the PASTA domains of this enzyme. This binding predisposes the third pentapeptide stem in the same nascent peptidoglycan strand to penetration into the active site for the turnover events. The complexation of the two pentapeptide stems in the same peptidoglycan strand is a recognition motif for the nascent peptidoglycan, critical for the cell-wall cross-linking reaction.
Collapse
Affiliation(s)
- Noelia Bernardo-García
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry “Rocasolano,” CSIC, 28006 Madrid, Spain
| | - Kiran V. Mahasenan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - María T. Batuecas
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry “Rocasolano,” CSIC, 28006 Madrid, Spain
| | - Mijoon Lee
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Dusan Hesek
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Denisa Petráčková
- Institute of Microbiology, v.v.i, Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Linda Doubravová
- Institute of Microbiology, v.v.i, Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Pavel Branny
- Institute of Microbiology, v.v.i, Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Juan A. Hermoso
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry “Rocasolano,” CSIC, 28006 Madrid, Spain
| |
Collapse
|
38
|
Takada H, Yoshikawa H. Essentiality and function of WalK/WalR two-component system: the past, present, and future of research. Biosci Biotechnol Biochem 2018. [PMID: 29514560 DOI: 10.1080/09168451.2018.1444466] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The WalK/WalR two-component system (TCS), originally identified in Bacillus subtilis, is very highly conserved in gram-positive bacteria, including several important pathogens. The WalK/WalR TCS appears to be involved in the growth of most bacterial species encoding it. Previous studies have indicated conserved functions of this system, defining this signal transduction pathway as a crucial regulatory system for cell wall metabolism. Because of such effects on essential functions, this system is considered a potential target for anti-infective therapeutics. In this review, we discuss the role of WalK/WalR TCS in different bacterial cells, focusing on the function of the genes in its regulon as well as the variations in walRK operon structure, its auxiliary proteins, and the composition of its regulon. We also discuss recent experimental data addressing its essential function and the potential type of signal being sensed by B. subtilis. This review also focuses on the potential future research.
Collapse
Affiliation(s)
- Hiraku Takada
- Department of Life Science and Research Center for Life Science, College of Science, Rikkyo University, Tokyo, Japan.,Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | | |
Collapse
|
39
|
Phosphorylation-dependent activation of the cell wall synthase PBP2a in Streptococcus pneumoniae by MacP. Proc Natl Acad Sci U S A 2018; 115:2812-2817. [PMID: 29487215 DOI: 10.1073/pnas.1715218115] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Most bacterial cells are surrounded by an essential cell wall composed of the net-like heteropolymer peptidoglycan (PG). Growth and division of bacteria are intimately linked to the expansion of the PG meshwork and the construction of a cell wall septum that separates the nascent daughter cells. Class A penicillin-binding proteins (aPBPs) are a major family of PG synthases that build the wall matrix. Given their central role in cell wall assembly and importance as drug targets, surprisingly little is known about how the activity of aPBPs is controlled to properly coordinate cell growth and division. Here, we report the identification of MacP (SPD_0876) as a membrane-anchored cofactor of PBP2a, an aPBP synthase of the Gram-positive pathogen Streptococcus pneumoniae We show that MacP localizes to the division site of S. pneumoniae, forms a complex with PBP2a, and is required for the in vivo activity of the synthase. Importantly, MacP was also found to be a substrate for the kinase StkP, a global cell cycle regulator. Although StkP has been implicated in controlling the balance between the elongation and septation modes of cell wall synthesis, none of its substrates are known to modulate PG synthetic activity. Here we show that a phosphoablative substitution in MacP that blocks StkP-mediated phosphorylation prevents PBP2a activity without affecting the MacP-PBP2a interaction. Our results thus reveal a direct connection between PG synthase function and the control of cell morphogenesis by the StkP regulatory network.
Collapse
|
40
|
Adediran SA, Sarkar KS, Pratt RF. Kinetic Evidence for a Second Ligand Binding Site on Streptococcus pneumoniae Penicillin-Binding Protein 2x. Biochemistry 2018; 57:1758-1766. [PMID: 29485264 DOI: 10.1021/acs.biochem.7b01209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High molecular mass penicillin-binding proteins (PBPs, DD-peptidases) of class B, such as Streptococcus pneumoniae PBP2x, catalyze the cross-linking of peptidoglycan in bacterial cell wall biosynthesis and are thus important antibiotic targets. Despite their importance in this regard, structure-function studies of ligands of these enzymes have been impeded by the absence of useful substrates. In vitro, these enzymes do not catalyze peptide hydrolysis or aminolysis, their in vivo reaction, but some, such as PBP2x, do catalyze these reactions of certain thioesters such as PhCH2CONHCH2COSCH(D-Me)CO2- (2). We have now prepared several peptidoglycan-mimetic thioesters that we expected to more closely resemble the natural substrates of these enzymes. To our surprise, however, these compounds, although indeed substrates of PBP2x, did not, unlike 2, appear to form an acyl-enzyme intermediate during hydrolysis, and their turnover was inhibited by certain peptides and N-acylamino acids much more weakly than that of 2. An inhibitor of this type, N-benzyloxycarbonyl-d-glutamic acid, also quenched the fluorescence of PBP2x that had been labeled at the DD-peptidase active site by 6-dansylamidopenicillanic acid. These results were interpreted in terms of a model where the peptidoglycan-mimetic thioesters preferentially bound to and hydrolyzed at a site other than the classical DD-peptidase active site. This second site is likely to represent part of an extended binding site that accommodates a peptidoglycan substrate or regulator in vivo. Such a site may be a target for future inhibitor/antibiotic design.
Collapse
Affiliation(s)
- S A Adediran
- Department of Chemistry , Wesleyan University , Lawn Avenue , Middletown , Connecticut 06459 , United States
| | - Kumar Subarno Sarkar
- Department of Chemistry , Wesleyan University , Lawn Avenue , Middletown , Connecticut 06459 , United States
| | - R F Pratt
- Department of Chemistry , Wesleyan University , Lawn Avenue , Middletown , Connecticut 06459 , United States
| |
Collapse
|
41
|
Zucchini L, Mercy C, Garcia PS, Cluzel C, Gueguen-Chaignon V, Galisson F, Freton C, Guiral S, Brochier-Armanet C, Gouet P, Grangeasse C. PASTA repeats of the protein kinase StkP interconnect cell constriction and separation of Streptococcus pneumoniae. Nat Microbiol 2018; 3:197-209. [PMID: 29203882 DOI: 10.1038/s41564-017-0069-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 10/23/2017] [Indexed: 11/09/2022]
Abstract
Eukaryotic-like serine/threonine kinases (eSTKs) with extracellular PASTA repeats are key membrane regulators of bacterial cell division. How PASTA repeats govern eSTK activation and function remains elusive. Using evolution- and structural-guided approaches combined with cell imaging, we disentangle the role of each PASTA repeat of the eSTK StkP from Streptococcus pneumoniae. While the three membrane-proximal PASTA repeats behave as interchangeable modules required for the activation of StkP independently of cell wall binding, they also control the septal cell wall thickness. In contrast, the fourth and membrane-distal PASTA repeat directs StkP localization at the division septum and encompasses a specific motif that is critical for final cell separation through interaction with the cell wall hydrolase LytB. We propose a model in which the extracellular four-PASTA domain of StkP plays a dual function in interconnecting the phosphorylation of StkP endogenous targets along with septal cell wall remodelling to allow cell division of the pneumococcus.
Collapse
Affiliation(s)
- Laure Zucchini
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Chryslène Mercy
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Pierre Simon Garcia
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
- Laboratoire de Biométrie et Biologie Evolutive, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Caroline Cluzel
- Laboratoire de Biologie Tissulaire et d'Ingénierie Thérapeutique, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Virginie Gueguen-Chaignon
- Protein Science Facility, Structure Fédérative de Recherche Biosciences/UMS3444/US8, Université Claude Bernard Lyon 1, Ecole Normale Supérieur de Lyon, INSERM, Centre National de la Recherche Scientifique, Lyon, France
| | - Frédéric Galisson
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Céline Freton
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Sébastien Guiral
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Céline Brochier-Armanet
- Laboratoire de Biométrie et Biologie Evolutive, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Patrice Gouet
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France
| | - Christophe Grangeasse
- Molecular Microbiology and Structural Biochemistry, Unité Mixte de Recherche, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique, Lyon, France.
| |
Collapse
|
42
|
Pompeo F, Byrne D, Mengin-Lecreulx D, Galinier A. Dual regulation of activity and intracellular localization of the PASTA kinase PrkC during Bacillus subtilis growth. Sci Rep 2018; 8:1660. [PMID: 29374241 PMCID: PMC5786024 DOI: 10.1038/s41598-018-20145-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/15/2018] [Indexed: 12/13/2022] Open
Abstract
The activity of the PrkC protein kinase is regulated in a sophisticated manner in Bacillus subtilis cells. In spores, in the presence of muropeptides, PrkC stimulates dormancy exit. The extracellular region containing PASTA domains binds peptidoglycan fragments to probably enhance the intracellular kinase activity. During exponential growth, the cell division protein GpsB interacts with the intracellular domain of PrkC to stimulate its activity. In this paper, we have reinvestigated the regulation of PrkC during exponential and stationary phases. We observed that, during exponential growth, neither its septal localization nor its activity are influenced by the addition of peptidoglycan fragments or by the deletion of one or all PASTA domains. However, Dynamic Light Scattering experiments suggest that peptidoglycan fragments bind specifically to PrkC and induce its oligomerization. In addition, during stationary phase, PrkC appeared evenly distributed in the cell wall and the deletion of one or all PASTA domains led to a non-activated kinase. We conclude that PrkC activation is not as straightforward as previously suggested and that regulation of its kinase activity via the PASTA domains and peptidoglycan fragments binding occurs when PrkC is not concentrated to the bacterial septum, but all over the cell wall in non-dividing bacillus cells.
Collapse
Affiliation(s)
- Frédérique Pompeo
- Laboratoire de Chimie Bactérienne, UMR 7283, IMM, CNRS, Aix Marseille Univ, 31 Chemin Joseph Aiguier, 13009, Marseille, France.
| | - Deborah Byrne
- Protein Expression Facility, IMM, CNRS, Aix Marseille Univ, 31 Chemin Joseph Aiguier, 13009, Marseille, France
| | - Dominique Mengin-Lecreulx
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud and Université Paris-Saclay, 91198, Gif-sur-Yvette, France
| | - Anne Galinier
- Laboratoire de Chimie Bactérienne, UMR 7283, IMM, CNRS, Aix Marseille Univ, 31 Chemin Joseph Aiguier, 13009, Marseille, France
| |
Collapse
|
43
|
Peterson E, Kaur P. Antibiotic Resistance Mechanisms in Bacteria: Relationships Between Resistance Determinants of Antibiotic Producers, Environmental Bacteria, and Clinical Pathogens. Front Microbiol 2018; 9:2928. [PMID: 30555448 DOI: 10.3389/fmicb.2018.02928/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/14/2018] [Indexed: 05/20/2023] Open
Abstract
Emergence of antibiotic resistant pathogenic bacteria poses a serious public health challenge worldwide. However, antibiotic resistance genes are not confined to the clinic; instead they are widely prevalent in different bacterial populations in the environment. Therefore, to understand development of antibiotic resistance in pathogens, we need to consider important reservoirs of resistance genes, which may include determinants that confer self-resistance in antibiotic producing soil bacteria and genes encoding intrinsic resistance mechanisms present in all or most non-producer environmental bacteria. While the presence of resistance determinants in soil and environmental bacteria does not pose a threat to human health, their mobilization to new hosts and their expression under different contexts, for example their transfer to plasmids and integrons in pathogenic bacteria, can translate into a problem of huge proportions, as discussed in this review. Selective pressure brought about by human activities further results in enrichment of such determinants in bacterial populations. Thus, there is an urgent need to understand distribution of resistance determinants in bacterial populations, elucidate resistance mechanisms, and determine environmental factors that promote their dissemination. This comprehensive review describes the major known self-resistance mechanisms found in producer soil bacteria of the genus Streptomyces and explores the relationships between resistance determinants found in producer soil bacteria, non-producer environmental bacteria, and clinical isolates. Specific examples highlighting potential pathways by which pathogenic clinical isolates might acquire these resistance determinants from soil and environmental bacteria are also discussed. Overall, this article provides a conceptual framework for understanding the complexity of the problem of emergence of antibiotic resistance in the clinic. Availability of such knowledge will allow researchers to build models for dissemination of resistance genes and for developing interventions to prevent recruitment of additional or novel genes into pathogens.
Collapse
Affiliation(s)
- Elizabeth Peterson
- Department of Biology, Georgia State University, Atlanta, GA, United States
| | - Parjit Kaur
- Department of Biology, Georgia State University, Atlanta, GA, United States
| |
Collapse
|
44
|
Mattos-Graner RO, Duncan MJ. Two-component signal transduction systems in oral bacteria. J Oral Microbiol 2017; 9:1400858. [PMID: 29209465 PMCID: PMC5706477 DOI: 10.1080/20002297.2017.1400858] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/01/2017] [Indexed: 01/03/2023] Open
Abstract
We present an overview of how members of the oral microbiota respond to their environment by regulating gene expression through two-component signal transduction systems (TCSs) to support conditions compatible with homeostasis in oral biofilms or drive the equilibrium toward dysbiosis in response to environmental changes. Using studies on the sub-gingival Gram-negative anaerobe Porphyromonas gingivalis and Gram-positive streptococci as examples, we focus on the molecular mechanisms involved in activation of TCS and species specificities of TCS regulons.
Collapse
Affiliation(s)
- Renata O. Mattos-Graner
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas – UNICAMP, São Paulo, Brazil
| | - Margaret J. Duncan
- Department of Oral Medicine, Infection and Immunity, The Forsyth Institute, Cambridge, MA, USA
| |
Collapse
|
45
|
Huang Y, Chen DH, Liu BY, Shen WH, Ruan Y. Conservation and diversification of polycomb repressive complex 2 (PRC2) proteins in the green lineage. Brief Funct Genomics 2017; 16:106-119. [PMID: 27032420 DOI: 10.1093/bfgp/elw007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The polycomb group (PcG) proteins are key epigenetic regulators of gene expression in animals and plants. They act in multiprotein complexes, of which the best characterized is the polycomb repressive complex 2 (PRC2), which catalyses the trimethylation of histone H3 at lysine 27 (H3K27me3) at chromatin targets. In Arabidopsis thaliana, PRC2 proteins are involved in the regulation of diverse developmental processes, including cell fate determination, vegetative growth and development, flowering time control and embryogenesis. Here, we systematically analysed the evolutionary conservation and diversification of PRC2 components in lower and higher plants. We searched for and identified PRC2 homologues from the sequenced genomes of several green lineage species, from the unicellular green alga Ostreococcus lucimarinus to more complicated angiosperms. We found that some PRC2 core components, e.g. E(z), ESC/FIE and MSI/p55, are ancient and have multiplied coincidently with multicellular evolution. For one component, some members are newly formed, especially in the Cruciferae. During evolution, higher plants underwent copy number multiplication of various PRC2 components, which occurred independently for each component, without any obvious co-amplification of PRC2 members. Among the amplified members, usually one was well-conserved and the others were more diversified. Gene amplification occurred at different times for different PcG members during green lineage evolution. Certain PRC2 core components or members of them were highly conserved. Our study provides an insight into the evolutionary conservation and diversification of PcG proteins and may guide future functional characterization of these important epigenetic regulators in plants other than Arabidopsis.
Collapse
Affiliation(s)
- Yong Huang
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-FU-HAU On Plant Epigenome Research, Hunan Agricultural University, Changsha, China.,Key Laboratory of Education, Department of Hunan Province On Plant Genetics and Molecular Biology, Hunan Agricultural University, Changsha, China
| | - Dong-Hong Chen
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-FU-HAU On Plant Epigenome Research, Hunan Agricultural University, Changsha, China.,Key Laboratory of Education, Department of Hunan Province On Plant Genetics and Molecular Biology, Hunan Agricultural University, Changsha, China
| | - Bo-Yu Liu
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, China
| | - Wen-Hui Shen
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-FU-HAU On Plant Epigenome Research, Hunan Agricultural University, Changsha, China.,Institut de Biologie Moléculaire Des Plantes Du CNRS, Université de Strasbourg, 12 Rue Du Général Zimmer, Strasbourg Cedex, France
| | - Ying Ruan
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-FU-HAU On Plant Epigenome Research, Hunan Agricultural University, Changsha, China.,Key Laboratory of Education, Department of Hunan Province On Plant Genetics and Molecular Biology, Hunan Agricultural University, Changsha, China.,Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, China
| |
Collapse
|
46
|
Wang Q, Marchetti R, Prisic S, Ishii K, Arai Y, Ohta I, Inuki S, Uchiyama S, Silipo A, Molinaro A, Husson RN, Fukase K, Fujimoto Y. A Comprehensive Study of the Interaction between Peptidoglycan Fragments and the Extracellular Domain of Mycobacterium tuberculosis Ser/Thr Kinase PknB. Chembiochem 2017; 18:2094-2098. [PMID: 28851116 PMCID: PMC6261334 DOI: 10.1002/cbic.201700385] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Indexed: 11/07/2022]
Abstract
The Mycobacterium tuberculosis Ser/Thr kinase PknB is implicated in the regulation of bacterial cell growth and cell division. The intracellular kinase function of PknB is thought to be triggered by peptidoglycan (PGN) fragments that are recognized by the extracytoplasmic domain of PknB. The PGN in the cell wall of M. tuberculosis has several unusual modifications, including the presence of N-glycolyl groups (in addition to N-acetyl groups) in the muramic acid residues and amidation of d-Glu in the peptide chains. Using synthetic PGN fragments incorporating these diverse PGN structures, we analyzed their binding characters through biolayer interferometry (BLI), NMR spectroscopy, and native mass spectrometry (nMS) techniques. The results of BLI showed that muropeptides containing 1,6-anhydro-MurNAc and longer glycan chains exhibited higher binding potency and that the fourth amino acid of the peptide stem, d-Ala, was crucial for protein recognition. Saturation transfer difference (STD) NMR spectroscopy indicated the major involvement of the stem peptide region in the PASTA-PGN fragment binding. nMS suggested that the binding stoichiometry was 1:1. The data provide the first molecular basis for the specific interaction of PGN with PknB and firmly establish PGNs as the effective ligands of PknB.
Collapse
Affiliation(s)
- Qianqian Wang
- Faculty of Science and Technology, Keio University, Hiyoshi 3--14-1, Yokohama, Kanagawa 223--8522 (Japan),
- Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560--0043 (Japan)
| | - Roberta Marchetti
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cinthia 4, 80126 Napoli (Italy)
| | - Sladjana Prisic
- Division of Infectious Disease, Children’s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (USA),
| | - Kentaro Ishii
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444--8787 (Japan)
| | - Yohei Arai
- Faculty of Science and Technology, Keio University, Hiyoshi 3--14-1, Yokohama, Kanagawa 223--8522 (Japan),
| | - Ippei Ohta
- Faculty of Science and Technology, Keio University, Hiyoshi 3--14-1, Yokohama, Kanagawa 223--8522 (Japan),
| | - Shinsuke Inuki
- Faculty of Science and Technology, Keio University, Hiyoshi 3--14-1, Yokohama, Kanagawa 223--8522 (Japan),
| | - Susumu Uchiyama
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444--8787 (Japan)
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565--0871 (Japan)
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cinthia 4, 80126 Napoli (Italy)
| | - Antonio Molinaro
- Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560--0043 (Japan)
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cinthia 4, 80126 Napoli (Italy)
| | - Robert N. Husson
- Division of Infectious Disease, Children’s Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (USA),
| | - Koichi Fukase
- Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560--0043 (Japan)
| | - Yukari Fujimoto
- Faculty of Science and Technology, Keio University, Hiyoshi 3--14-1, Yokohama, Kanagawa 223--8522 (Japan),
| |
Collapse
|
47
|
Schaenzer AJ, Wlodarchak N, Drewry DH, Zuercher WJ, Rose WE, Striker R, Sauer JD. A screen for kinase inhibitors identifies antimicrobial imidazopyridine aminofurazans as specific inhibitors of the Listeria monocytogenes PASTA kinase PrkA. J Biol Chem 2017; 292:17037-17045. [PMID: 28821610 PMCID: PMC5641865 DOI: 10.1074/jbc.m117.808600] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 08/14/2017] [Indexed: 01/17/2023] Open
Abstract
Bacterial signaling systems such as protein kinases and quorum sensing have become increasingly attractive targets for the development of novel antimicrobial agents in a time of rising antibiotic resistance. The family of bacterial Penicillin-binding-protein And Serine/Threonine kinase-Associated (PASTA) kinases is of particular interest due to the role of these kinases in regulating resistance to β-lactam antibiotics. As such, small-molecule kinase inhibitors that target PASTA kinases may prove beneficial as treatments adjunctive to β-lactam therapy. Despite this interest, only limited progress has been made in identifying functional inhibitors of the PASTA kinases that have both activity against the intact microbe and high kinase specificity. Here, we report the results of a small-molecule screen that identified GSK690693, an imidazopyridine aminofurazan-type kinase inhibitor that increases the sensitivity of the intracellular pathogen Listeria monocytogenes to various β-lactams by inhibiting the PASTA kinase PrkA. GSK690693 potently inhibited PrkA kinase activity biochemically and exhibited significant selectivity for PrkA relative to the Staphylococcus aureus PASTA kinase Stk1. Furthermore, other imidazopyridine aminofurazans could effectively inhibit PrkA and potentiate β-lactam antibiotic activity to varying degrees. The presence of the 2-methyl-3-butyn-2-ol (alkynol) moiety was important for both biochemical and antimicrobial activity. Finally, mutagenesis studies demonstrated residues in the back pocket of the active site are important for GSK690693 selectivity. These data suggest that targeted screens can successfully identify PASTA kinase inhibitors with both biochemical and antimicrobial specificity. Moreover, the imidazopyridine aminofurazans represent a family of PASTA kinase inhibitors that have the potential to be optimized for selective PASTA kinase inhibition.
Collapse
Affiliation(s)
- Adam J Schaenzer
- From the Departments of Medical Microbiology and Immunology and
- Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Nathan Wlodarchak
- From the Departments of Medical Microbiology and Immunology and
- Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - David H Drewry
- the Structural Genomics Consortium-University of North Carolina at Chapel Hill (SGC-UNC), University of North Carolina at Chapel Hill Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - William J Zuercher
- the Structural Genomics Consortium-University of North Carolina at Chapel Hill (SGC-UNC), University of North Carolina at Chapel Hill Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - Warren E Rose
- Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
- the School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, and
| | - Rob Striker
- From the Departments of Medical Microbiology and Immunology and
- Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
- the Department of Molecular and Cell Biology, W. S. Middleton Memorial Veteran's Hospital, Madison, Wisconsin 53705
| | | |
Collapse
|
48
|
Growth- and Stress-Induced PASTA Kinase Phosphorylation in Enterococcus faecalis. J Bacteriol 2017; 199:JB.00363-17. [PMID: 28808126 DOI: 10.1128/jb.00363-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 08/04/2017] [Indexed: 12/22/2022] Open
Abstract
Transmembrane Ser/Thr kinases containing extracellular PASTA domains are ubiquitous among Actinobacteria and Firmicutes Such PASTA kinases regulate critical processes, including antibiotic resistance, cell division, toxin production, and virulence, and are essential for viability in certain organisms. Based on in vitro studies with purified extracellular and intracellular fragments of PASTA kinases, a model for signaling has been proposed, in which the extracellular PASTA domains bind currently undefined ligands (typically thought to be peptidoglycan, or fragments thereof) to drive kinase dimerization, which leads to enhanced kinase autophosphorylation and enhanced phosphorylation of substrates. However, this model has not been rigorously tested in vivoEnterococcus faecalis is a Gram-positive intestinal commensal and major antibiotic-resistant opportunistic pathogen. In E. faecalis, the PASTA kinase IreK drives intrinsic resistance to cell wall-active antimicrobials, suggesting that such antimicrobials may trigger IreK signaling. Here we show that IreK responds to cell wall stress in vivo by enhancing its phosphorylation and that of a downstream substrate. This response requires both the extracellular PASTA domains and specific phosphorylatable residues in the kinase domain. Thus, our results provide in vivo evidence, with an intact full-length PASTA kinase in its native physiological environment, that supports the prevailing model of PASTA kinase signaling. In addition, we show that IreK responds to a signal associated with growth and/or cell division, in the absence of cell wall-active antimicrobials. Surprisingly, the ability of IreK to respond to growth and/or division does not require the extracellular PASTA domains, suggesting that IreK monitors multiple parameters for sensory input in vivoIMPORTANCE Transmembrane Ser/Thr kinases containing extracellular PASTA domains are ubiquitous among Actinobacteria and Firmicutes and regulate critical processes. The prevailing model for signaling by PASTA kinases proposes that the extracellular PASTA domains bind ligands to drive kinase dimerization, enhanced autophosphorylation, and enhanced phosphorylation of substrates. However, this model has not been rigorously tested in vivo We show that the PASTA kinase IreK of Enterococcus faecalis responds to cell wall stress in vivo by enhancing its phosphorylation and that of a downstream substrate. This response requires the PASTA domains and phosphorylatable residues in the kinase domain. Thus, our results provide in vivo evidence, with an intact full-length PASTA kinase in its native physiological environment, that supports the prevailing model of PASTA kinase signaling.
Collapse
|
49
|
Bae HJ, Lee HN, Baek MN, Park EJ, Eom CY, Ko IJ, Kang HY, Oh JI. Inhibition of the DevSR Two-Component System by Overexpression of Mycobacterium tuberculosis PknB in Mycobacterium smegmatis. Mol Cells 2017; 40:632-642. [PMID: 28843272 PMCID: PMC5638771 DOI: 10.14348/molcells.2017.0076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/11/2017] [Accepted: 07/24/2017] [Indexed: 01/29/2023] Open
Abstract
The DevSR (DosSR) two-component system, which is a major regulatory system involved in oxygen sensing in mycobacteria, plays an important role in hypoxic induction of many genes in mycobacteria. We demonstrated that overexpression of the kinase domain of Mycobacterium tuberculosis (Mtb) PknB inhibited transcriptional activity of the DevR response regulator in Mycobacterium smegmatis and that this inhibitory effect was exerted through phosphorylation of DevR on Thr180 within its DNA-binding domain. Moreover, the purified kinase domain of Mtb PknB significantly phosphorylated RegX3, NarL, KdpE, TrcR, DosR, and MtrA response regulators of Mtb that contain the Thr residues corresponding to Thr180 of DevR in their DNA-binding domains, implying that transcriptional activities of these response regulators might also be inhibited when the kinase domain of PknB is overexpressed.
Collapse
Affiliation(s)
- Hyun-Jung Bae
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| | - Ha-Na Lee
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| | - Mi-Na Baek
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| | - Eun-Jin Park
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| | - Chi-Yong Eom
- Korea Basic Science Institute, Seoul 02855,
Korea
| | - In-Jeong Ko
- Korea Science Academy of KAIST, Busan 47162,
Korea
| | - Ho-Young Kang
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| | - Jeong-Il Oh
- Department of Microbiology, Pusan National University, Busan 46241,
Korea
| |
Collapse
|
50
|
Patel S, Rauf A, Meher BR. In silico analysis of ChtBD3 domain to find its role in bacterial pathogenesis and beyond. Microb Pathog 2017; 110:519-526. [PMID: 28760454 DOI: 10.1016/j.micpath.2017.07.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 07/24/2017] [Accepted: 07/27/2017] [Indexed: 12/12/2022]
Abstract
Chitin binding domain 3, known by the acronym ChtBD3, is a domain in the enzymes and proteins of several pathogenic virus, bacteria and fungi. As this domain is evolutionarily-conserved in virulence factors of these infectious agents, its detailed investigation is of clinical interest. In this regard, the current in silico study analyzed ChtBD3 domain distribution in bacterial proteins present in publicly-available SMART (simple modular architecture research tool) database. Also, the co-occurring domains of ChtBD3 in the studied proteins were mapped to understand positional rearrangement of the domain and consequent functional diversity. Custom-made scripts were used to interpret the data and to derive patterns. As expected, interesting results were obtained. ChtBD3 domain co-occurred with other critical domains like peptidase, glycol_hydrolase, kinase, hemagglutinin-acting, collagen-binding, among others. The findings are expected to be of clinical relevance.
Collapse
Affiliation(s)
- Seema Patel
- Bioinformatics and Medical Informatics Research Center, San Diego State University, San Diego, 92182, USA.
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Anbar, 23561, Khyber Pakhtunkhwa, Pakistan.
| | - Biswa Ranjan Meher
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi, 835205, Jharkhand, India
| |
Collapse
|