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Agaras BC, Grossi CEM, Ulloa RM. Unveiling the Secrets of Calcium-Dependent Proteins in Plant Growth-Promoting Rhizobacteria: An Abundance of Discoveries Awaits. PLANTS (BASEL, SWITZERLAND) 2023; 12:3398. [PMID: 37836138 PMCID: PMC10574481 DOI: 10.3390/plants12193398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023]
Abstract
The role of Calcium ions (Ca2+) is extensively documented and comprehensively understood in eukaryotic organisms. Nevertheless, emerging insights, primarily derived from studies on human pathogenic bacteria, suggest that this ion also plays a pivotal role in prokaryotes. In this review, our primary focus will be on unraveling the intricate Ca2+ toolkit within prokaryotic organisms, with particular emphasis on its implications for plant growth-promoting rhizobacteria (PGPR). We undertook an in silico exploration to pinpoint and identify some of the proteins described in the existing literature, including prokaryotic Ca2+ channels, pumps, and exchangers that are responsible for regulating intracellular Calcium concentration ([Ca2+]i), along with the Calcium-binding proteins (CaBPs) that play a pivotal role in sensing and transducing this essential cation. These investigations were conducted in four distinct PGPR strains: Pseudomonas chlororaphis subsp. aurantiaca SMMP3, P. donghuensis SVBP6, Pseudomonas sp. BP01, and Methylobacterium sp. 2A, which have been isolated and characterized within our research laboratories. We also present preliminary experimental data to evaluate the influence of exogenous Ca2+ concentrations ([Ca2+]ex) on the growth dynamics of these strains.
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Affiliation(s)
- Betina Cecilia Agaras
- Laboratory of Physiology and Genetics of Plant Probiotic Bacteria (LFGBBP), Centre of Biochemistry and Microbiology of Soils, National University of Quilmes, Bernal B1876BXD, Argentina
- National Scientific and Technical Research Council (CONICET), Buenos Aires C1425FQB, Argentina;
| | - Cecilia Eugenia María Grossi
- National Scientific and Technical Research Council (CONICET), Buenos Aires C1425FQB, Argentina;
- Laboratory of Plant Signal Transduction, Institute of Genetic Engineering and Molecular Biology (INGEBI), National Scientific and Technical Research Council (CONICET), Buenos Aires C1425FQB, Argentina
| | - Rita María Ulloa
- National Scientific and Technical Research Council (CONICET), Buenos Aires C1425FQB, Argentina;
- Laboratory of Plant Signal Transduction, Institute of Genetic Engineering and Molecular Biology (INGEBI), National Scientific and Technical Research Council (CONICET), Buenos Aires C1425FQB, Argentina
- Biochemistry Department, Faculty of Exact and Natural Sciences, University of Buenos Aires (FCEN-UBA), Buenos Aires C1428EGA, Argentina
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Clara L, David C, Laila S, Virginie R, Marie-Joelle V. Comparative Proteomic Analysis of Transcriptional and Regulatory Proteins Abundances in S. lividans and S. coelicolor Suggests a Link between Various Stresses and Antibiotic Production. Int J Mol Sci 2022; 23:ijms232314792. [PMID: 36499130 PMCID: PMC9739823 DOI: 10.3390/ijms232314792] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 11/29/2022] Open
Abstract
Streptomyces coelicolor and Streptomyces lividans constitute model strains to study the regulation of antibiotics biosynthesis in Streptomyces species since these closely related strains possess the same pathways directing the biosynthesis of various antibiotics but only S. coelicolor produces them. To get a better understanding of the origin of the contrasted abilities of these strains to produce bioactive specialized metabolites, these strains were grown in conditions of phosphate limitation or proficiency and a comparative analysis of their transcriptional/regulatory proteins was carried out. The abundance of the vast majority of the 355 proteins detected greatly differed between these two strains and responded differently to phosphate availability. This study confirmed, consistently with previous studies, that S. coelicolor suffers from nitrogen stress. This stress likely triggers the degradation of the nitrogen-rich peptidoglycan cell wall in order to recycle nitrogen present in its constituents, resulting in cell wall stress. When an altered cell wall is unable to fulfill its osmo-protective function, the bacteria also suffer from osmotic stress. This study thus revealed that these three stresses are intimately linked in S. coelicolor. The aggravation of these stresses leading to an increase of antibiotic biosynthesis, the connection between these stresses, and antibiotic production are discussed.
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Affiliation(s)
- Lejeune Clara
- Institute for Integrative Biology of the Cell (I2BC), Department of Microbiology, Group “Energetic Metabolism of Streptomyces”, CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Cornu David
- Institute for Integrative Biology of the Cell (I2BC), Department of Microbiology, Group “Energetic Metabolism of Streptomyces”, CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Sago Laila
- Institute for Integrative Biology of the Cell (I2BC), Department of Microbiology, Group “Energetic Metabolism of Streptomyces”, CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Redeker Virginie
- Institute for Integrative Biology of the Cell (I2BC), Department of Microbiology, Group “Energetic Metabolism of Streptomyces”, CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
- Laboratory of Neurodegenerative Diseases, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA) and Centre National de la Recherche Scientifique (CNRS), Molecular Imaging Center (MIRCen), Institut François Jacob, Université Paris-Saclay, 92260 Fontenay-aux-Roses, France
| | - Virolle Marie-Joelle
- Institute for Integrative Biology of the Cell (I2BC), Department of Microbiology, Group “Energetic Metabolism of Streptomyces”, CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
- Correspondence:
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King MM, Kayastha BB, Franklin MJ, Patrauchan MA. Calcium Regulation of Bacterial Virulence. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:827-855. [PMID: 31646536 DOI: 10.1007/978-3-030-12457-1_33] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Calcium (Ca2+) is a universal signaling ion, whose major informational role shaped the evolution of signaling pathways, enabling cellular communications and responsiveness to both the intracellular and extracellular environments. Elaborate Ca2+ regulatory networks have been well characterized in eukaryotic cells, where Ca2+ regulates a number of essential cellular processes, ranging from cell division, transport and motility, to apoptosis and pathogenesis. However, in bacteria, the knowledge on Ca2+ signaling is still fragmentary. This is complicated by the large variability of environments that bacteria inhabit with diverse levels of Ca2+. Yet another complication arises when bacterial pathogens invade a host and become exposed to different levels of Ca2+ that (1) are tightly regulated by the host, (2) control host defenses including immune responses to bacterial infections, and (3) become impaired during diseases. The invading pathogens evolved to recognize and respond to the host Ca2+, triggering the molecular mechanisms of adhesion, biofilm formation, host cellular damage, and host-defense resistance, processes enabling the development of persistent infections. In this review, we discuss: (1) Ca2+ as a determinant of a host environment for invading bacterial pathogens, (2) the role of Ca2+ in regulating main events of host colonization and bacterial virulence, and (3) the molecular mechanisms of Ca2+ signaling in bacterial pathogens.
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Affiliation(s)
- Michelle M King
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Biraj B Kayastha
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Michael J Franklin
- Department of Microbiology and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.
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4
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Sharma A, Laxman B, Naureckas ET, Hogarth DK, Sperling AI, Solway J, Ober C, Gilbert JA, White SR. Associations between fungal and bacterial microbiota of airways and asthma endotypes. J Allergy Clin Immunol 2019; 144:1214-1227.e7. [PMID: 31279011 PMCID: PMC6842419 DOI: 10.1016/j.jaci.2019.06.025] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 06/12/2019] [Accepted: 06/19/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND The relationship between asthma, atopy, and underlying type 2 (T2) airway inflammation is complex. Although the bacterial airway microbiota is known to differ in asthmatic patients, the fungal and bacterial markers that discriminate T2-high (eosinophilic) and T2-low (neutrophilic/mixed-inflammation) asthma and atopy are still incompletely identified. OBJECTIVES The aim of this study was to demonstrate the fungal microbiota structure of airways in asthmatic patients associated with T2 inflammation, atopy, and key clinical parameters. METHODS We collected endobronchial brush (EB) and bronchoalveolar lavage (BAL) samples from 39 asthmatic patients and 19 healthy subjects followed by 16S gene and internal transcribed spacer-based microbiota sequencing. The microbial sequences were classified into exact sequence variants. The T2 phenotype was defined by using a blood eosinophil count with a threshold of 300 cells/μL. RESULTS Fungal diversity was significantly lower in EB samples from patients with T2-high compared with T2-low inflammation; key fungal genera enriched in patients with T2-high inflammation included Trichoderma species, whereas Penicillium species was enriched in patients with atopy. In BAL fluid samples the dominant genera were Cladosporium, Fusarium, Aspergillus, and Alternaria. Using generalized linear models, we identified significant associations between specific fungal exact sequence variants and FEV1, fraction of exhaled nitric oxide values, BAL fluid cell counts, and corticosteroid use. Investigation of interkingdom (bacterial-fungal) co-occurrence patterns revealed different topologies between asthmatic patients and healthy control subjects. Random forest models with fungal classifiers predicted asthma status with 75% accuracy for BAL fluid samples and 80% accuracy for EB samples. CONCLUSIONS We demonstrate clear differences in bacterial and fungal microbiota in asthma-associated phenotypes. Our study provides additional support for considering microbial signatures in delineating asthma phenotypes.
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Affiliation(s)
- Anukriti Sharma
- Department of Surgery, University of Chicago, Chicago, Ill; Biosciences Division (BIO), Argonne National Laboratory, Argonne, Ill; Department of Pediatrics and Scripps Institution of Oceanography, University of California San Diego, La Jolla, Calif
| | - Bharathi Laxman
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill
| | - Edward T Naureckas
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill
| | - D Kyle Hogarth
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill
| | - Anne I Sperling
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill
| | - Julian Solway
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill
| | - Carole Ober
- Department of Human Genetics, University of Chicago, Chicago, Ill
| | - Jack A Gilbert
- Department of Surgery, University of Chicago, Chicago, Ill; Biosciences Division (BIO), Argonne National Laboratory, Argonne, Ill; Department of Pediatrics and Scripps Institution of Oceanography, University of California San Diego, La Jolla, Calif
| | - Steven R White
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Ill.
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Plattner H, Verkhratsky A. The ancient roots of calcium signalling evolutionary tree. Cell Calcium 2015; 57:123-32. [DOI: 10.1016/j.ceca.2014.12.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 12/05/2014] [Indexed: 12/26/2022]
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6
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Calcium binding proteins and calcium signaling in prokaryotes. Cell Calcium 2014; 57:151-65. [PMID: 25555683 DOI: 10.1016/j.ceca.2014.12.006] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/08/2014] [Accepted: 12/09/2014] [Indexed: 11/20/2022]
Abstract
With the continued increase of genomic information and computational analyses during the recent years, the number of newly discovered calcium binding proteins (CaBPs) in prokaryotic organisms has increased dramatically. These proteins contain sequences that closely resemble a variety of eukaryotic calcium (Ca(2+)) binding motifs including the canonical and pseudo EF-hand motifs, Ca(2+)-binding β-roll, Greek key motif and a novel putative Ca(2+)-binding domain, called the Big domain. Prokaryotic CaBPs have been implicated in diverse cellular activities such as division, development, motility, homeostasis, stress response, secretion, transport, signaling and host-pathogen interactions. However, the majority of these proteins are hypothetical, and only few of them have been studied functionally. The finding of many diverse CaBPs in prokaryotic genomes opens an exciting area of research to explore and define the role of Ca(2+) in organisms other than eukaryotes. This review presents the most recent developments in the field of CaBPs and novel advancements in the role of Ca(2+) in prokaryotes.
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Sarkisova SA, Lotlikar SR, Guragain M, Kubat R, Cloud J, Franklin MJ, Patrauchan MA. A Pseudomonas aeruginosa EF-hand protein, EfhP (PA4107), modulates stress responses and virulence at high calcium concentration. PLoS One 2014; 9:e98985. [PMID: 24918783 PMCID: PMC4053335 DOI: 10.1371/journal.pone.0098985] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 05/09/2014] [Indexed: 12/18/2022] Open
Abstract
Pseudomonas aeruginosa is a facultative human pathogen, and a major cause of nosocomial infections and severe chronic infections in endocarditis and in cystic fibrosis (CF) patients. Calcium (Ca2+) accumulates in pulmonary fluids of CF patients, and plays a role in the hyperinflammatory response to bacterial infection. Earlier we showed that P. aeruginosa responds to increased Ca2+ levels, primarily through the increased production of secreted virulence factors. Here we describe the role of putative Ca2+-binding protein, with an EF-hand domain, PA4107 (EfhP), in this response. Deletion mutations of efhP were generated in P. aeruginosa strain PAO1 and CF pulmonary isolate, strain FRD1. The lack of EfhP abolished the ability of P. aeruginosa PAO1 to maintain intracellular Ca2+ homeostasis. Quantitative high-resolution 2D-PAGE showed that the efhP deletion also affected the proteomes of both strains during growth with added Ca2+. The greatest proteome effects occurred when the pulmonary isolate was cultured in biofilms. Among the proteins that were significantly less abundant or absent in the mutant strains were proteins involved in iron acquisition, biosynthesis of pyocyanin, proteases, and stress response proteins. In support, the phenotypic responses of FRD1 ΔefhP showed that the mutant strain lost its ability to produce pyocyanin, developed less biofilm, and had decreased resistance to oxidative stress (H2O2) when cultured at high [Ca2+]. Furthermore, the mutant strain was unable to produce alginate when grown at high [Ca2+] and no iron. The effect of the ΔefhP mutations on virulence was determined in a lettuce model of infection. Growth of wild-type P. aeruginosa strains at high [Ca2+] causes an increased area of disease. In contrast, the lack of efhP prevented this Ca2+-induced increase in the diseased zone. The results indicate that EfhP is important for Ca2+ homeostasis and virulence of P. aeruginosa when it encounters host environments with high [Ca2+].
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Affiliation(s)
- Svetlana A. Sarkisova
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Shalaka R. Lotlikar
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Manita Guragain
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Ryan Kubat
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - John Cloud
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Michael J. Franklin
- Department of Microbiology, Montana State University, Bozeman, Montana, United States of America
- Center for Biofilm Engineering, Montana State University, Bozeman, Montana, United States of America
| | - Marianna A. Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, United States of America
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Arockiasamy A, Aggarwal A, Savva CG, Holzenburg A, Sacchettini JC. Crystal structure of calcium dodecin (Rv0379), from Mycobacterium tuberculosis with a unique calcium-binding site. Protein Sci 2011; 20:827-33. [PMID: 21370306 PMCID: PMC3125867 DOI: 10.1002/pro.607] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 02/01/2011] [Indexed: 01/07/2023]
Abstract
In eukaryotes, calcium-binding proteins play a pivotal role in diverse cellular processes, and recent findings suggest similar roles for bacterial proteins at different stages in their life cycle. Here, we report the crystal structure of calcium dodecin, Rv0379, from Mycobacterium tuberculosis with a dodecameric oligomeric assembly and a unique calcium-binding motif. Structure and sequence analysis were used to identify orthologs of Rv0379 with different ligand-binding specificity.
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Affiliation(s)
- Arulandu Arockiasamy
- Department of Biochemistry and Biophysics, Texas A&M University, College StationTexas 77843-2128
| | - Anup Aggarwal
- Department of Biochemistry and Biophysics, Texas A&M University, College StationTexas 77843-2128
| | - Christos G Savva
- Microscopy and Imaging Center and Department of Biology, Texas A&M University, Biological Sciences Building West, College StationTexas 77843-2257
| | - Andreas Holzenburg
- Microscopy and Imaging Center and Department of Biology, Texas A&M University, Biological Sciences Building West, College StationTexas 77843-2257
| | - James C Sacchettini
- Department of Biochemistry and Biophysics, Texas A&M University, College StationTexas 77843-2128
- Center for Structural Biology, Institute of Biosciences and TechnologyHouston, Texas 77030
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Dobson LF, O’Shea DG. Antagonistic effect of divalent cations Ca2+ and Mg2+ on the morphological development of Streptomyces hygroscopicus var. geldanus. Appl Microbiol Biotechnol 2008; 81:119-26. [DOI: 10.1007/s00253-008-1627-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2008] [Revised: 07/15/2008] [Accepted: 07/18/2008] [Indexed: 01/13/2023]
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CabC, an EF-hand calcium-binding protein, is involved in Ca2+-mediated regulation of spore germination and aerial hypha formation in Streptomyces coelicolor. J Bacteriol 2008; 190:4061-8. [PMID: 18375559 DOI: 10.1128/jb.01954-07] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Ca(2+) was reported to regulate spore germination and aerial hypha formation in streptomycetes; the underlying mechanism of this regulation is not known. cabC, a gene encoding an EF-hand calcium-binding protein, was disrupted or overexpressed in Streptomyces coelicolor M145. On R5- agar, the disruption of cabC resulted in denser aerial hyphae with more short branches, swollen hyphal tips, and early-germinating spores on the spore chain, while cabC overexpression significantly delayed development. Manipulation of the Ca(2+) concentration in R5- agar could reverse the phenotypes of cabC disruption or overexpression mutants and mimic mutant phenotypes with M145, suggesting that the mutant phenotypes were due to changes in the intracellular Ca(2+) concentration. CabC expression was strongly activated in aerial hyphae, as determined by Western blotting against CabC and confocal laser scanning microscopy detection of CabC::enhanced green fluorescent protein (EGFP). CabC::EGFP fusion proteins were evenly distributed in substrate mycelia, aerial mycelia, and spores. Taken together, these results demonstrate that CabC is involved in Ca(2+)-mediated regulation of spore germination and aerial hypha formation in S. coelicolor. CabC most likely acts as a Ca(2+) buffer and exerts its regulatory effects by controlling the intracellular Ca(2+) concentration.
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Amaral L, Martins M, Viveiros M. Enhanced killing of intracellular multidrug-resistant Mycobacterium tuberculosis by compounds that affect the activity of efflux pumps. J Antimicrob Chemother 2007; 59:1237-46. [PMID: 17218448 DOI: 10.1093/jac/dkl500] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Whereas human neutrophils are effective and efficient killers of bacteria, macrophages such as those derived from monocytes are almost devoid of killing activity. Nevertheless, monocytes can be transformed into effective killers of mycobacteria or staphylococci when exposed to clinical concentrations of a phenothiazine or to inhibitors of efflux pumps (reserpine and verapamil), or to ouabain, an inhibitor of K(+) transport. Because the rates of multidrug-resistant Mycobacterium tuberculosis (MDR-TB) continue to escalate globally, and because no new effective drug has been made available for almost 40 years, compounds that enhance the killing activity of monocytes against MDR-TB are obviously needed. This review covers the specific characteristics of MDR-TB, identifies a variety of agents that address these characteristics and therefore have potential for managing MDR-TB. Because the mechanism by which these agents enhance the killing of intracellular bacteria is important for the intelligent design of new anti-tubercular agents, the review correlates the mechanisms by which these agents manifest their effects. Lastly, a model is presented which describes the mechanisms by which distinct efflux pumps of the phagosome-lysosome complex are inhibited by agents that are known to inhibit K(+) flux. The model also predicts the existence of a K(+) activated exchange (pump) that is probably located in the membrane that delineates the lysosome. This putative pump, which is immune to inhibitors of K+ flux, is identified as being the cause for the acidification of the lysosome thereby activating its hydrolytic enzymes. Because the non-killer macrophage can be transformed into an effective killer by a variety of compounds that inhibit K(+) transport, perhaps it would be wise to develop drugs that enhance the killing activity of these cells inasmuch as this approach would not be subject to any resistance, as is the eventual case for conventional antibiotics.
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Affiliation(s)
- Leonard Amaral
- Unidade de Micobacterias, UPMM, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 96, Lisboa, Portugal.
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Zhou Y, Yang W, Kirberger M, Lee HW, Ayalasomayajula G, Yang JJ. Prediction of EF-hand calcium-binding proteins and analysis of bacterial EF-hand proteins. Proteins 2007; 65:643-55. [PMID: 16981205 DOI: 10.1002/prot.21139] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The EF-hand protein with a helix-loop-helix Ca(2+) binding motif constitutes one of the largest protein families and is involved in numerous biological processes. To facilitate the understanding of the role of Ca(2+) in biological systems using genomic information, we report, herein, our improvement on the pattern search method for the identification of EF-hand and EF-like Ca(2+)-binding proteins. The canonical EF-hand patterns are modified to cater to different flanking structural elements. In addition, on the basis of the conserved sequence of both the N- and C-terminal EF-hands within S100 and S100-like proteins, a new signature profile has been established to allow for the identification of pseudo EF-hand and S100 proteins from genomic information. The new patterns have a positive predictive value of 99% and a sensitivity of 96% for pseudo EF-hands. Furthermore, using the developed patterns, we have identified zero pseudo EF-hand motif and 467 canonical EF-hand Ca(2+) binding motifs with diverse cellular functions in the bacteria genome. The prediction results imply that pseudo EF-hand motifs are phylogenetically younger than canonical EF-hand motifs. Our prediction of Ca(2+) binding motifs provides not only an insight into the role of Ca(2+) and Ca(2+)-binding proteins in bacterial systems, but also a way to explore and define the role of Ca(2+) in other biological systems (calciomics).
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Affiliation(s)
- Yubin Zhou
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, USA
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