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Wu W, Huang J, Xu Z. Antibiotic influx and efflux in Pseudomonas aeruginosa: Regulation and therapeutic implications. Microb Biotechnol 2024; 17:e14487. [PMID: 38801351 PMCID: PMC11129675 DOI: 10.1111/1751-7915.14487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024] Open
Abstract
Pseudomonas aeruginosa is a notorious multidrug-resistant pathogen that poses a serious and growing threat to the worldwide public health. The expression of resistance determinants is exquisitely modulated by the abundant regulatory proteins and the intricate signal sensing and transduction systems in this pathogen. Downregulation of antibiotic influx porin proteins and upregulation of antibiotic efflux pump systems owing to mutational changes in their regulators or the presence of distinct inducing molecular signals represent two of the most efficient mechanisms that restrict intracellular antibiotic accumulation and enable P. aeruginosa to resist multiple antibiotics. Treatment of P. aeruginosa infections is extremely challenging due to the highly inducible mechanism of antibiotic resistance. This review comprehensively summarizes the regulatory networks of the major porin proteins (OprD and OprH) and efflux pumps (MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY) that play critical roles in antibiotic influx and efflux in P. aeruginosa. It also discusses promising therapeutic approaches using safe and efficient adjuvants to enhance the efficacy of conventional antibiotics to combat multidrug-resistant P. aeruginosa by controlling the expression levels of porins and efflux pumps. This review not only highlights the complexity of the regulatory network that induces antibiotic resistance in P. aeruginosa but also provides important therapeutic implications in targeting the inducible mechanism of resistance.
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Affiliation(s)
- Weiyan Wu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
| | - Jiahui Huang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
| | - Zeling Xu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
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2
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Burch-Konda J, Kayastha BB, Kubo A, Achour M, Hull M, Braga R, Winton L, Rogers RR, McCoy J, Lutter EI, Patrauchan MA. EF-Hand Calcium Sensor, EfhP, Controls Transcriptional Regulation of Iron Uptake by Calcium in Pseudomonas aeruginosa. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.09.574892. [PMID: 38260268 PMCID: PMC10802428 DOI: 10.1101/2024.01.09.574892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The human pathogen Pseudomonas aeruginosa poses a major risk for a range of severe infections, particularly lung infections in patients suffering from cystic fibrosis (CF). As previously reported, the virulent behavior of this pathogen is enhanced by elevated levels of Ca 2+ that are commonly present in CF nasal and lung fluids. In addition, a Ca 2+ -binding EF-hand protein, EfhP (PA4107), was partially characterized and shown to be critical for the Ca 2+ -regulated virulence in P. aeruginosa . Here we describe the rapid (10 min, 60 min), and adaptive (12 h) transcriptional responses of PAO1 to elevated Ca 2+ detected by genome-wide RNA sequencing and show that efhP deletion significantly hindered both rapid and adaptive Ca 2+ regulation. The most differentially regulated genes included multiple Fe sequestering mechanisms, a large number of extracytoplasmic function sigma factors (ECFσ) and several virulence factors, such as production of pyocins. The Ca 2+ regulation of Fe uptake was also observed in CF clinical isolates and appeared to involve the global regulator Fur. In addition, we showed that the efhP transcription is controlled by Ca 2+ and Fe, and this regulation required Ca 2+ -dependent two-component regulatory system CarSR. Furthermore, the efhP expression is significantly increased in CF clinical isolates and upon pathogen internalization into epithelial cells. Overall, the results established for the first time that Ca 2+ controls Fe sequestering mechanisms in P. aeruginosa and that EfhP plays a key role in the regulatory interconnectedness between Ca 2+ and Fe signaling pathways, the two distinct and important signaling pathways that guide the pathogen's adaptation to host. IMPORTANCE Pseudomonas aeruginosa ( Pa ) poses a major risk for severe infections, particularly in patients suffering from cystic fibrosis (CF). For the first time, kinetic RNA sequencing analysis identified Pa rapid and adaptive transcriptional responses to Ca 2+ levels consistent with those present in CF respiratory fluids. The most highly upregulated processes include iron sequestering, iron starvation sigma factors, and self-lysis factors pyocins. An EF-hand Ca 2+ sensor, EfhP, is required for at least 1/3 of the Ca 2+ response, including all the iron uptake mechanisms and production of pyocins. Transcription of efhP itself is regulated by Ca 2+ , Fe, and increases during interactions with host epithelial cells, suggesting the protein's important role in Pa infections. The findings establish the regulatory interconnectedness between Ca 2+ and iron signaling pathways that shape Pa transcriptional responses. Therefore, understanding Pa's transcriptional response to Ca 2+ and associated regulatory mechanisms will serve the development of future therapeutics targeting Pa dangerous infections.
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Kolodkin-Gal I, Parsek MR, Patrauchan MA. The roles of calcium signaling and calcium deposition in microbial multicellularity. Trends Microbiol 2023; 31:1225-1237. [PMID: 37429751 PMCID: PMC10772221 DOI: 10.1016/j.tim.2023.06.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 07/12/2023]
Abstract
Calcium signaling is an essential mediator of signal-controlling gene expression in most developmental systems. In addition, calcium has established extracellular functions as a structural component of biogenic minerals found in complex tissues. In bacteria, the formation of calcium carbonate structures is associated with complex colony morphology. Genes promoting the formation of biogenic minerals are essential for proper biofilm development and protection against antimicrobial solutes and toxins. Here we review recent findings on the role of calcium and calcium signaling as emerging regulators of biofilm formation in beneficial bacteria, as well as essential mediators of biofilm formation and virulence in human pathogens. The presented analysis concludes that the new understanding of calcium signaling may help to improve the performance of beneficial strains for sustainable agriculture, microbiome manipulation, and sustainable construction. Unraveling the roles of calcium may also promote the development of novel therapies against biofilm infections that target calcium uptake, calcium sensors, and calcium carbonate deposition.
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Affiliation(s)
- Ilana Kolodkin-Gal
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
| | - Matthew R Parsek
- Department of Microbiology, University of Washington, Seattle, WA, USA.
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.
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Jeong GJ, Khan F, Tabassum N, Kim YM. Natural and synthetic molecules with potential to enhance biofilm formation and virulence properties in Pseudomonas aeruginosa. Crit Rev Microbiol 2023:1-29. [PMID: 37968960 DOI: 10.1080/1040841x.2023.2282459] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/01/2023] [Indexed: 11/17/2023]
Abstract
Pseudomonas aeruginosa can efficiently adapt to changing environmental conditions due to its ubiquitous nature, intrinsic/acquired/adaptive resistance mechanisms, high metabolic versatility, and the production of numerous virulence factors. As a result, P. aeruginosa becomes an opportunistic pathogen, causing chronic infection in the lungs and several organs of patients suffering from cystic fibrosis. Biofilm established by P. aeruginosa in host tissues and medical device surfaces has been identified as a major obstruction to antimicrobial therapy. P. aeruginosa is very likely to be closely associated with the various microorganisms in the host tissues or organs in a pathogenic or nonpathogenic behavior. Aside from host-derived molecules, other beneficial and pathogenic microorganisms produce a diverse range of secondary metabolites that either directly or indirectly favor the persistence of P. aeruginosa. Thus, it is critical to understand how P. aeruginosa interacts with different molecules and ions in the host and abiotic environment to produce extracellular polymeric substances and virulence factors. Thus, the current review discusses how various natural and synthetic molecules in the environment induce biofilm formation and the production of multiple virulence factors.
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Affiliation(s)
- Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, Republic of Korea
| | - Fazlurrahman Khan
- Institute of Fisheries Sciences, Pukyong National University, Busan, Republic of Korea
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, Republic of Korea
| | - Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, Republic of Korea
| | - Young-Mog Kim
- Department of Food Science and Technology, Pukyong National University, Busan, Republic of Korea
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, Republic of Korea
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Sultan M, Arya R, Chaurasia AK, Kim KK. Sensor histidine kinases kdpD and aauS regulate biofilm and virulence in Pseudomonas aeruginosa PA14. Front Cell Infect Microbiol 2023; 13:1270667. [PMID: 37881370 PMCID: PMC10595159 DOI: 10.3389/fcimb.2023.1270667] [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: 08/01/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
Pseudomonas aeruginosa is a multidrug-resistant opportunistic human pathogen that utilizes two-component systems (TCSs) to sense pathophysiological signals and coordinate virulence. P. aeruginosa contains 64 sensor histidine kinases (HKs) and 72 response regulators (RRs) that play important roles in metabolism, bacterial physiology, and virulence. However, the role of some TCSs in virulence remains uncharacterized. In this study, we evaluated the virulence potential of some uncharacterized sensor HK and RR knockouts in P. aeruginosa using a Galleria mellonella infection model. Furthermore, we demonstrated that KdpD and AauS HKs regulate virulence by affecting P. aeruginosa biofilm formation and motility. Both ΔkdpD and ΔaauS showed reduced biofilm and motility which were confirmed by restored phenotypes upon complementation. Moreover, ΔkdpD and ΔaauS exhibited increased survival of HeLa cells and G. mellonella during in vivo infection. Altered expression of the transcriptional regulators anR and lasR, along with the virulence genes lasA, pelA, cupA, pqsA, pqsB, pqsC, and pqsD in the mutant strains elucidated the mechanism by which ΔkdpD and ΔaauS affect virulence. These findings confirm that kdpD and aauS play important roles in P. aeruginosa pathogenesis by regulating biofilm formation and motility.
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Affiliation(s)
- Maria Sultan
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Rekha Arya
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
- Department of Orthopedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Akhilesh Kumar Chaurasia
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Kyeong Kyu Kim
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
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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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The Pseudomonas aeruginosa RpoH (σ 32) Regulon and Its Role in Essential Cellular Functions, Starvation Survival, and Antibiotic Tolerance. Int J Mol Sci 2023; 24:ijms24021513. [PMID: 36675051 PMCID: PMC9866376 DOI: 10.3390/ijms24021513] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/23/2022] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
The bacterial heat-shock response is regulated by the alternative sigma factor, σ32 (RpoH), which responds to misfolded protein stress and directs the RNA polymerase to the promoters for genes required for protein refolding or degradation. In P. aeruginosa, RpoH is essential for viability under laboratory growth conditions. Here, we used a transcriptomics approach to identify the genes of the RpoH regulon, including RpoH-regulated genes that are essential for P. aeruginosa. We placed the rpoH gene under control of the arabinose-inducible PBAD promoter, then deleted the chromosomal rpoH allele. This allowed transcriptomic analysis of the RpoH (σ32) regulon following a short up-shift in the cellular concentration of RpoH by arabinose addition, in the absence of a sudden change in temperature. The P. aeruginosa ∆rpoH (PBAD-rpoH) strain grew in the absence of arabinose, indicating that some rpoH expression occurred without arabinose induction. When arabinose was added, the rpoH mRNA abundance of P. aeruginosa ∆rpoH (PBAD-rpoH) measured by RT-qPCR increased five-fold within 15 min of arabinose addition. Transcriptome results showed that P. aeruginosa genes required for protein repair or degradation are induced by increased RpoH levels, and that many genes essential for P. aeruginosa growth are induced by RpoH. Other stress response genes induced by RpoH are involved in damaged nucleic acid repair and in amino acid metabolism. Annotation of the hypothetical proteins under RpoH control included proteins that may play a role in antibiotic resistances and in non-ribosomal peptide synthesis. Phenotypic analysis of P. aeruginosa ∆rpoH (PBAD-rpoH) showed that it is impaired in its ability to survive during starvation compared to the wild-type strain. P. aeruginosa ∆rpoH (PBAD-rpoH) also had increased sensitivity to aminoglycoside antibiotics, but not to other classes of antibiotics, whether cultured planktonically or in biofilms. The enhanced aminoglycoside sensitivity of the mutant strain may be due to indirect effects, such as the build-up of toxic misfolded proteins, or to the direct effect of genes, such as aminoglycoside acetyl transferases, that are regulated by RpoH. Overall, the results demonstrate that RpoH regulates genes that are essential for viability of P. aeruginosa, that it protects P. aeruginosa from damage from aminoglycoside antibiotics, and that it is required for survival during nutrient-limiting conditions.
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8
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Nocentini A, Capasso C, Supuran CT. Carbonic Anhydrase Inhibitors as Novel Antibacterials in the Era of Antibiotic Resistance: Where Are We Now? Antibiotics (Basel) 2023; 12:antibiotics12010142. [PMID: 36671343 PMCID: PMC9854953 DOI: 10.3390/antibiotics12010142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 12/29/2022] [Accepted: 01/09/2023] [Indexed: 01/12/2023] Open
Abstract
Resistance to antibiotic treatment developed by bacteria in humans and animals occurs when the microorganisms resist treatment with clinically approved antibiotics. Actions must be implemented to stop the further development of antibiotic resistance and the subsequent emergence of superbugs. Medication repurposing/repositioning is one strategy that can help find new antibiotics, as it speeds up drug development phases. Among them, the Zn2+ ion binders, such as sulfonamides and their bioisosteres, are considered the most promising compounds to obtain novel antibacterials, thus avoiding antibiotic resistance. Sulfonamides and their bioisosteres have drug-like properties well-known for decades and are suitable lead compounds for developing new pharmacological agent families for inhibiting carbonic anhydrases (CAs). CAs are a superfamily of metalloenzymes catalyzing the reversible reaction of CO2 hydration to HCO3- and H+, being present in most bacteria in multiple genetic families (α-, β-, γ- and ι-classes). These enzymes, acting as CO2 transducers, are promising drug targets because their activity influences microbe proliferation, biosynthetic pathways, and pathogen persistence in the host. In their natural or slightly modified scaffolds, sulfonamides/sulfamates/sulamides inhibit CAs in vitro and in vivo, in mouse models infected with antibiotic-resistant strains, confirming thus their role in contrasting bacterial antibiotic resistance.
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Affiliation(s)
- Alessio Nocentini
- NEUROFARBA Department, Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, 50019 Firenze, Italy
| | - Clemente Capasso
- Department of Biology, Agriculture and Food Sciences, Institute of Biosciences and Bioresources, CNR, 80131 Napoli, Italy
- Correspondence: (C.C.); (C.T.S.)
| | - Claudiu T. Supuran
- NEUROFARBA Department, Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, 50019 Firenze, Italy
- Correspondence: (C.C.); (C.T.S.)
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9
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In Vivo Role of Two-Component Regulatory Systems in Models of Urinary Tract Infections. Pathogens 2023; 12:pathogens12010119. [PMID: 36678467 PMCID: PMC9861413 DOI: 10.3390/pathogens12010119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/23/2022] [Accepted: 01/08/2023] [Indexed: 01/12/2023] Open
Abstract
Two-component signaling systems (TCSs) are finely regulated mechanisms by which bacteria adapt to environmental conditions by modifying the expression of target genes. In bacterial pathogenesis, TCSs play important roles in modulating adhesion to mucosal surfaces, resistance to antibiotics, and metabolic adaptation. In the context of urinary tract infections (UTI), one of the most common types infections causing significant health problems worldwide, uropathogens use TCSs for adaptation, survival, and establishment of pathogenicity. For example, uropathogens can exploit TCSs to survive inside bladder epithelial cells, sense osmolar variations in urine, promote their ascension along the urinary tract or even produce lytic enzymes resulting in exfoliation of the urothelium. Despite the usefulness of studying the function of TCSs in in vitro experimental models, it is of primary necessity to study bacterial gene regulation also in the context of host niches, each displaying its own biological, chemical, and physical features. In light of this, the aim of this review is to provide a concise description of several bacterial TCSs, whose activity has been described in mouse models of UTI.
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10
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Holban AM, Gregoire CM, Gestal MC. Conquering the host: Bordetella spp. and Pseudomonas aeruginosa molecular regulators in lung infection. Front Microbiol 2022; 13:983149. [PMID: 36225372 PMCID: PMC9549215 DOI: 10.3389/fmicb.2022.983149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/17/2022] [Indexed: 11/27/2022] Open
Abstract
When bacteria sense cues from the host environment, stress responses are activated. Two component systems, sigma factors, small RNAs, ppGpp stringent response, and chaperones start coordinate the expression of virulence factors or immunomodulators to allow bacteria to respond. Although, some of these are well studied, such as the two-component systems, the contribution of other regulators, such as sigma factors or ppGpp, is increasingly gaining attention. Pseudomonas aeruginosa is the gold standard pathogen for studying the molecular mechanisms to sense and respond to environmental cues. Bordetella spp., on the other hand, is a microbial model for studying host-pathogen interactions at the molecular level. These two pathogens have the ability to colonize the lungs of patients with chronic diseases, suggesting that they have the potential to share a niche and interact. However, the molecular networks that facilitate adaptation of Bordetella spp. to cues are unclear. Here, we offer a side-by-side comparison of what is known about these diverse molecular mechanisms that bacteria utilize to counteract host immune responses, while highlighting the relatively unexplored interactions between them.
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Affiliation(s)
- Alina M. Holban
- Research Institute of the University of Bucharest (ICUB), Bucharest, Romania
- Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Courtney M. Gregoire
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA, United States
| | - Monica C. Gestal
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA, United States
- *Correspondence: Monica C. Gestal, ;
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Arakawa K, Yanai J, Watanabe K. Study of the Ca2+-dependent gene expression of EuPrt, an extracellular metalloprotease produced by the psychro-tolerant bacterium Exiguobacterium undae Su-1. Biosci Biotechnol Biochem 2022; 86:1308-1317. [PMID: 35776951 DOI: 10.1093/bbb/zbac109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 05/31/2022] [Indexed: 11/14/2022]
Abstract
The effect of a Ca2+ ion on the gene expression of an on-demand type of metalloprotease from psychrotrophic Exiguobacterium undae Su-1 (EuPrt) was studied. We first established a modified mM9 medium for strain Su-1 to examine its effect in more detail. Then, when the strain was cultured in mM9 medium and 1.0 mM CaCl2 was added, we detected the mature EuPrt and its precursor proteins via Western blotting analysis and found the relative protease activity and its transcription increased by 50-fold and 7-fold, respectively, at the peak. Furthermore, the intracellular concentration of Ca2+ ions was analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES) with other metal ions along the growth of strain Su-1. The intracellular concentration of Ca2+ ion was found to increase as much as 3-fold in response to the addition of an extracellular Ca2+ ions, indicating that euPrt gene expression is regulated by sensing its intracellular concentration.
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Affiliation(s)
- Kiyoaki Arakawa
- Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo, Kyoto, Japan
| | - Junta Yanai
- Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo, Kyoto, Japan
| | - Kunihiko Watanabe
- Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo, Kyoto, Japan
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12
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Kayastha BB, Kubo A, Burch-Konda J, Dohmen RL, McCoy JL, Rogers RR, Mares S, Bevere J, Huckaby A, Witt W, Peng S, Chaudhary B, Mohanty S, Barbier M, Cook G, Deng J, Patrauchan MA. EF-hand protein, EfhP, specifically binds Ca 2+ and mediates Ca 2+ regulation of virulence in a human pathogen Pseudomonas aeruginosa. Sci Rep 2022; 12:8791. [PMID: 35614085 PMCID: PMC9132961 DOI: 10.1038/s41598-022-12584-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/09/2022] [Indexed: 11/30/2022] Open
Abstract
Calcium (Ca2+) is well known as a second messenger in eukaryotes, where Ca2+ signaling controls life-sustaining cellular processes. Although bacteria produce the components required for Ca2+ signaling, little is known about the mechanisms of bacterial Ca2+ signaling. Previously, we have identified a putative Ca2+-binding protein EfhP (PA4107) with two canonical EF-hand motifs and reported that EfhP mediates Ca2+ regulation of virulence factors production and infectivity in Pseudomonas aeruginosa, a human pathogen causing life-threatening infections. Here, we show that EfhP selectively binds Ca2+ with 13.7 µM affinity, and that mutations at the +X and -Z positions within each or both EF-hand motifs abolished Ca2+ binding. We also show that the hydrophobicity of EfhP increased in a Ca2+-dependent manner, however no such response was detected in the mutated proteins. 15 N-NMR showed Ca2+-dependent chemical shifts in EfhP confirming Ca2+-binding triggered structural rearrangements in the protein. Deletion of efhP impaired P. aeruginosa survival in macrophages and virulence in vivo. Disabling EfhP Ca2+ binding abolished Ca2+ induction of pyocyanin production in vitro. These data confirm that EfhP selectively binds Ca2+, which triggers its structural changes required for the Ca2+ regulation of P. aeruginosa virulence, thus establishing the role of EfhP as a Ca2+ sensor.
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Affiliation(s)
- Biraj B Kayastha
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Aya Kubo
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jacob Burch-Konda
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Rosalie L Dohmen
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jacee L McCoy
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Rendi R Rogers
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Sergio Mares
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Justin Bevere
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Annalisa Huckaby
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - William Witt
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Shuxia Peng
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Bharat Chaudhary
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Smita Mohanty
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Mariette Barbier
- Vaccine Development Center at West Virginia University, Morgantown, WV, 26506, USA
- Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Gabriel Cook
- Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Junpeng Deng
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, 74078, USA.
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13
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Zhao Y, Wee CY, Zhang H, Yang Z, Wang WEJ, Thian ES. Silver-substituted hydroxyapatite inhibits Pseudomonas aeruginosa outer membrane protein F: A potential antibacterial mechanism. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2022; 134:112713. [DOI: 10.1016/j.msec.2022.112713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/06/2022] [Accepted: 02/09/2022] [Indexed: 12/20/2022]
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14
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Ducret V, Perron K, Valentini M. Role of Two-Component System Networks in Pseudomonas aeruginosa Pathogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:371-395. [PMID: 36258080 DOI: 10.1007/978-3-031-08491-1_14] [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: 06/16/2023]
Abstract
Two-component systems (TCS) are the largest family of signaling systems in the bacterial kingdom. They enable bacteria to cope with a wide range of environmental conditions via the sensing of stimuli and the transduction of the signal into an appropriate cellular adaptation response. Pseudomonas aeruginosa possesses one of the richest arrays of TCSs in bacteria and they have been the subject of intense investigation for more than 20 years. Most of the P. aeruginosa TCSs characterized to date affect its pathogenesis, via the regulation of virulence factors expression, modulation of the synthesis of antibiotic/antimicrobial resistance mechanisms, and/or via linking virulence to energy metabolism. Here, we give an overview of the current knowledge on P. aeruginosa TCSs, citing key examples for each of the above-mentioned regulatory actions. We then conclude by mentioning few small molecule inhibitors of P. aeruginosa TCSs that have shown an antimicrobial action in vitro.
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Affiliation(s)
- Verena Ducret
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Karl Perron
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Martina Valentini
- Department of Microbiology and Molecular Medicine, CMU, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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15
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Lazar JT, Tabor JJ. Bacterial two-component systems as sensors for synthetic biology applications. CURRENT OPINION IN SYSTEMS BIOLOGY 2021; 28:100398. [PMID: 34917859 PMCID: PMC8670732 DOI: 10.1016/j.coisb.2021.100398] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Two-component systems (TCSs) are a ubiquitous family of signal transduction pathways that enable bacteria to sense and respond to diverse physical, chemical, and biological stimuli outside and inside the cell. Synthetic biologists have begun to repurpose TCSs for applications in optogenetics, materials science, gut microbiome engineering, and soil nutrient biosensing, among others. New engineering methods including genetic refactoring, DNA-binding domain swapping, detection threshold tuning, and phosphorylation cross-talk insulation are being used to increase the reliability of TCS sensor performance and tailor TCS signaling properties to the requirements of specific applications. There is now potential to combine these methods with large-scale gene synthesis and laboratory screening to discover the inputs sensed by many uncharacterized TCSs and develop a large new family of genetically-encoded sensors that respond to an unrivaled breadth of stimuli.
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Affiliation(s)
- John T Lazar
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, USA
| | - Jeffrey J Tabor
- Department of Bioengineering, Rice University, Houston, TX, USA
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, USA
- Department of Biosciences, Rice University, Houston, TX, USA
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16
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Sultan M, Arya R, Kim KK. Roles of Two-Component Systems in Pseudomonas aeruginosa Virulence. Int J Mol Sci 2021; 22:12152. [PMID: 34830033 PMCID: PMC8623646 DOI: 10.3390/ijms222212152] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 12/28/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that synthesizes and secretes a wide range of virulence factors. P. aeruginosa poses a potential threat to human health worldwide due to its omnipresent nature, robust host accumulation, high virulence, and significant resistance to multiple antibiotics. The pathogenicity of P. aeruginosa, which is associated with acute and chronic infections, is linked with multiple virulence factors and associated secretion systems, such as the ability to form and utilize a biofilm, pili, flagella, alginate, pyocyanin, proteases, and toxins. Two-component systems (TCSs) of P. aeruginosa perform an essential role in controlling virulence factors in response to internal and external stimuli. Therefore, understanding the mechanism of TCSs to perceive and respond to signals from the environment and control the production of virulence factors during infection is essential to understanding the diseases caused by P. aeruginosa infection and further develop new antibiotics to treat this pathogen. This review discusses the important virulence factors of P. aeruginosa and the understanding of their regulation through TCSs by focusing on biofilm, motility, pyocyanin, and cytotoxins.
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Affiliation(s)
| | - Rekha Arya
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Korea;
| | - Kyeong Kyu Kim
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon 16419, Korea;
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17
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Cianciulli Sesso A, Lilić B, Amman F, Wolfinger MT, Sonnleitner E, Bläsi U. Gene Expression Profiling of Pseudomonas aeruginosa Upon Exposure to Colistin and Tobramycin. Front Microbiol 2021; 12:626715. [PMID: 33995291 PMCID: PMC8120321 DOI: 10.3389/fmicb.2021.626715] [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: 11/06/2020] [Accepted: 03/31/2021] [Indexed: 11/22/2022] Open
Abstract
Pseudomonas aeruginosa (Pae) is notorious for its high-level resistance toward clinically used antibiotics. In fact, Pae has rendered most antimicrobials ineffective, leaving polymyxins and aminoglycosides as last resort antibiotics. Although several resistance mechanisms of Pae are known toward these drugs, a profounder knowledge of hitherto unidentified factors and pathways appears crucial to develop novel strategies to increase their efficacy. Here, we have performed for the first time transcriptome analyses and ribosome profiling in parallel with strain PA14 grown in synthetic cystic fibrosis medium upon exposure to polymyxin E (colistin) and tobramycin. This approach did not only confirm known mechanisms involved in colistin and tobramycin susceptibility but revealed also as yet unknown functions/pathways. Colistin treatment resulted primarily in an anti-oxidative stress response and in the de-regulation of the MexT and AlgU regulons, whereas exposure to tobramycin led predominantly to a rewiring of the expression of multiple amino acid catabolic genes, lower tricarboxylic acid (TCA) cycle genes, type II and VI secretion system genes and genes involved in bacterial motility and attachment, which could potentially lead to a decrease in drug uptake. Moreover, we report that the adverse effects of tobramycin on translation are countered with enhanced expression of genes involved in stalled ribosome rescue, tRNA methylation and type II toxin-antitoxin (TA) systems.
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Affiliation(s)
- Anastasia Cianciulli Sesso
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Branislav Lilić
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Fabian Amman
- Institute for Theoretical Chemistry, University of Vienna, Vienna, Austria
| | - Michael T Wolfinger
- Institute for Theoretical Chemistry, University of Vienna, Vienna, Austria.,Research Group Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - Elisabeth Sonnleitner
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Udo Bläsi
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
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18
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King M, Kubo A, Kafer L, Braga R, McLeod D, Khanam S, Conway T, Patrauchan MA. Calcium-Regulated Protein CarP Responds to Multiple Host Signals and Mediates Regulation of Pseudomonas aeruginosa Virulence by Calcium. Appl Environ Microbiol 2021; 87:e00061-21. [PMID: 33674436 PMCID: PMC8117776 DOI: 10.1128/aem.00061-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/27/2021] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen causing life-threatening infections. Previously, we showed that elevated calcium (Ca2+) levels increase the production of virulence factors in P. aeruginosa In an effort to characterize the Ca2+ regulatory network, we identified a Ca2+-regulated β-propeller protein, CarP, and showed that expression of the encoding gene is controlled by the Ca2+-regulated two-component system CarSR. Here, by using a Galleria melonella model, we showed that CarP plays a role in regulating P. aeruginosa virulence. By using transcriptome sequencing (RNA-Seq), reverse transcription (RT)-PCR, quantitative RT-PCR (RT-qPCR), and promoter fusions, we determined that carP is transcribed into at least two transcripts and regulated by several bacterial and host factors. The transcription of carP is elevated in response to Ca2+ in P. aeruginosa cystic fibrosis isolates and PAO1 laboratory strain. Elevated Fe2+ also induces carP The simultaneous addition of Ca2+ and Fe2+ increased the carP promoter activity synergistically, which requires the presence of CarR. In silico analysis of the intergenic sequence upstream of carP predicted recognition sites of RhlR/LasR, OxyR, and LexA, suggesting regulation by quorum sensing (QS) and oxidative stress. In agreement, the carP promoter was activated in response to stationary-phase PAO1 supernatant and required the presence of elevated Ca2+ and CarR but remained silent in the triple mutant lacking rhlI, lasI, and pqsA synthases. We also showed that carP transcription is regulated by oxidative stress and that CarP contributes to P. aeruginosa Ca2+-dependent H2O2 tolerance. The multifactorial regulation of carP suggests that CarP plays an important role in P. aeruginosa adaptations to host environments.IMPORTANCEP. aeruginosa is a human pathogen causing life-threatening infections. It is particularly notorious for its ability to adapt to diverse environments within the host. Understanding the signals and the signaling pathways enabling P. aeruginosa adaptation is imperative for developing effective therapies to treat infections caused by this organism. One host signal of particular importance is calcium. Previously, we identified a component of the P. aeruginosa calcium-signaling network, CarP, whose expression is induced by elevated levels of calcium. Here, we show that carP plays an important role in P. aeruginosa virulence and is upregulated in P. aeruginosa strains isolated from sputa of patients with cystic fibrosis. We also identified several bacterial and host factors that regulate the transcription of carP Such multifactorial regulation highlights the interconnectedness between regulatory circuits and, together with the pleotropic effect of CarP on virulence, suggests the importance of this protein in P. aeruginosa adaptations to the host.
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Affiliation(s)
- Michelle King
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Aya Kubo
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Leah Kafer
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Reygan Braga
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Daniel McLeod
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Sharmily Khanam
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Tyrrell Conway
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
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19
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Wang T, Sun W, Fan L, Hua C, Wu N, Fan S, Zhang J, Deng X, Yan J. An atlas of the binding specificities of transcription factors in Pseudomonas aeruginosa directs prediction of novel regulators in virulence. eLife 2021; 10:61885. [PMID: 33779544 PMCID: PMC8041468 DOI: 10.7554/elife.61885] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 03/26/2021] [Indexed: 12/14/2022] Open
Abstract
A high-throughput systematic evolution of ligands by exponential enrichment assay was applied to 371 putative TFs in Pseudomonas aeruginosa, which resulted in the robust enrichment of 199 unique sequence motifs describing the binding specificities of 182 TFs. By scanning the genome, we predicted in total 33,709 significant interactions between TFs and their target loci, which were more than 11-fold enriched in the intergenic regions but depleted in the gene body regions. To further explore and delineate the physiological and pathogenic roles of TFs in P. aeruginosa, we constructed regulatory networks for nine major virulence-associated pathways and found that 51 TFs were potentially significantly associated with these virulence pathways, 32 of which had not been characterized before, and some were even involved in multiple pathways. These results will significantly facilitate future studies on transcriptional regulation in P. aeruginosa and other relevant pathogens, and accelerate to discover effective treatment and prevention strategies for the associated infectious diseases.
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Affiliation(s)
- Tingting Wang
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
| | - Wenju Sun
- School of Medicine, Northwest University, Xi'an, China
| | - Ligang Fan
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China.,School of Medicine, Northwest University, Xi'an, China
| | - Canfeng Hua
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
| | - Nan Wu
- School of Medicine, Northwest University, Xi'an, China
| | - Shaorong Fan
- School of Medicine, Northwest University, Xi'an, China
| | - Jilin Zhang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Solna, Sweden
| | - Xin Deng
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
| | - Jian Yan
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China.,School of Medicine, Northwest University, Xi'an, China
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20
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Mares SE, King MM, Kubo A, Khanov AA, Lutter EI, Youssef N, Patrauchan MA. carP, encoding a Ca 2+-regulated putative phytase, is evolutionarily conserved in Pseudomonas aeruginosa and has potential as a biomarker. MICROBIOLOGY (READING, ENGLAND) 2021; 167:001004. [PMID: 33295862 PMCID: PMC8131022 DOI: 10.1099/mic.0.001004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 11/24/2020] [Indexed: 01/16/2023]
Abstract
Pseudomonas aeruginosa infects patients with cystic fibrosis, burns, wounds and implants. Previously, our group showed that elevated Ca2+ positively regulates the production of several virulence factors in P. aeruginosa, such as biofilm formation, production of pyocyanin and secreted proteases. We have identified a Ca2+-regulated β-propeller putative phytase, CarP, which is required for Ca2+ tolerance, regulation of the intracellular Ca2+ levels, and plays a role in Ca2+ regulation of P. aeruginosa virulence. Here, we studied the conservation of carP sequence and its occurrence in diverse phylogenetic groups of bacteria. In silico analysis revealed that carP and its two paralogues PA2017 and PA0319 are primarily present in P. aeruginosa and belong to the core genome of the species. We identified 155 single nucleotide alterations within carP, 42 of which lead to missense mutations with only three that affected the predicted 3D structure of the protein. PCR analyses with carP-specific primers detected P. aeruginosa specifically in 70 clinical and environmental samples. Sequence comparison demonstrated that carP is overall highly conserved in P. aeruginosa isolated from diverse environments. Such evolutionary preservation of carP illustrates its importance for P. aeruginosa adaptations to diverse environments and demonstrates its potential as a biomarker.
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Affiliation(s)
- Sergio E. Mares
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Michelle M. King
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Aya Kubo
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Anna A. Khanov
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Erika I. Lutter
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Noha Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Marianna A. Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
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21
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Felgner S, Preusse M, Beutling U, Stahnke S, Pawar V, Rohde M, Brönstrup M, Stradal T, Häussler S. Host-induced spermidine production in motile Pseudomonas aeruginosa triggers phagocytic uptake. eLife 2020; 9:e55744. [PMID: 32960172 PMCID: PMC7538158 DOI: 10.7554/elife.55744] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 09/15/2020] [Indexed: 12/31/2022] Open
Abstract
Exploring the complexity of host-pathogen communication is vital to understand why microbes persist within a host, while others are cleared. Here, we employed a dual-sequencing approach to unravel conversational turn-taking of dynamic host-pathogen communications. We demonstrate that upon hitting a host cell, motile Pseudomonas aeruginosa induce a specific gene expression program. This results in the expression of spermidine on the surface, which specifically activates the PIP3-pathway to induce phagocytic uptake into primary or immortalized murine cells. Non-motile bacteria are more immunogenic due to a lower expression of arnT upon host-cell contact, but do not produce spermidine and are phagocytosed less. We demonstrate that not only the presence of pathogen inherent molecular patterns induces immune responses, but that bacterial motility is linked to a host-cell-induced expression of additional immune modulators. Our results emphasize on the value of integrating microbiological and immunological findings to unravel complex and dynamic host-pathogen interactions.
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Affiliation(s)
- Sebastian Felgner
- Department of Molecular Bacteriology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Matthias Preusse
- Department of Molecular Bacteriology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Ulrike Beutling
- Department of Chemical Biology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Stephanie Stahnke
- Department of Cell Biology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Vinay Pawar
- Department of Molecular Bacteriology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Theresia Stradal
- Department of Cell Biology, Helmholtz Centre for Infection ResearchBraunschweigGermany
| | - Susanne Häussler
- Department of Molecular Bacteriology, Helmholtz Centre for Infection ResearchBraunschweigGermany
- Department of Molecular Bacteriology, TwincoreHannoverGermany
- Department of Clinical Microbiology, RigshospitaletCopenhagenDenmark
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical SchoolHannoverGermany
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22
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Karna SLR, Nguyen JQ, Evani SJ, Qian LW, Chen P, Abercrombie JJ, Sebastian EA, Fourcaudot AB, Leung KP. T3SS and alginate biosynthesis of Pseudomonas aeruginosa impair healing of infected rabbit wounds. Microb Pathog 2020; 147:104254. [PMID: 32416139 DOI: 10.1016/j.micpath.2020.104254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 05/05/2020] [Accepted: 05/08/2020] [Indexed: 10/24/2022]
Abstract
Pseudomonas aeruginosa (a Gram-negative bacterium) is an opportunistic pathogen found in many infected wounds and is known to impair healing. To test the hypothesis that knocking out P. aeruginosa genes that are overexpressed during wound infection can cripple a pathogen's ability to impair healing, we assessed two pathways: the Type III secretion system (T3SS) and alginate biosynthesis. We generated single- and double-mutant strains of ExsA (T3SS activator), AlgD (GDP- mannose 6-dehydrogenase of alginate biosynthesis) and their complemented strains and evaluated their pathogenicity in a rabbit ear full-thickness excision-wound infection model. Wounds were inoculated with different strains (wild type, mutants, and complementary strains) at 106 CFU/wound on post-wounding day 3. After 24 h, 5 days and 9 days post-infection, wounds were harvested for measuring bacterial counts (viable and total) and wound healing (epithelial gap). On day 9 post-infection, the viable counts of the double mutant, (exsA/algD)‾ were 100-fold lower than the counts of the wild type (PAO1), single mutants, or the complement double-mutant, (exsA/algD)‾/+. Also, when compared to wounds infected with wild type or control strains, wounds infected with the double-knockout mutant was less inhibitory to wound healing (p < 0.05). Additionally, the double mutant showed greater susceptibility to macrophage phagocytosis in vitro than all other strains (p < 0.001). In conclusion, compared to single gene knockouts, double knockout of virulence genes in T3SS pathway and alginate biosynthesis pathway is more effective in reducing P. aeruginosa pathogenicity and its ability to impair wound healing. This study highlights the necessity of a dual-targeted anti-virulence strategy to improve healing outcomes of P. aeruginosa-infected wounds.
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Affiliation(s)
- S L Rajasekhar Karna
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Jesse Q Nguyen
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Shankar Jaikishan Evani
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Li-Wu Qian
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Ping Chen
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Johnathan J Abercrombie
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Eliza A Sebastian
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Andrea B Fourcaudot
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA
| | - Kai P Leung
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX, USA.
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23
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Adaptive and Mutational Responses to Peptide Dendrimer Antimicrobials in Pseudomonas aeruginosa. Antimicrob Agents Chemother 2020; 64:AAC.02040-19. [PMID: 32015046 PMCID: PMC7179292 DOI: 10.1128/aac.02040-19] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 01/24/2020] [Indexed: 01/15/2023] Open
Abstract
Colistin (polymyxin E) is a last-resort antibiotic against multidrug-resistant isolates of Pseudomonas aeruginosa. However, the nephro-toxicity of colistin limits its use, spurring the interest in novel antimicrobial peptides (AMP). Here, we show that the synthetic AMP-dendrimer G3KL (MW 4,531.38 Da, 15 positive charges, MIC = 8 mg/liter) showed faster killing than polymyxin B (Pmx-B) with no detectable resistance selection in P. aeruginosa strain PA14. Colistin (polymyxin E) is a last-resort antibiotic against multidrug-resistant isolates of Pseudomonas aeruginosa. However, the nephro-toxicity of colistin limits its use, spurring the interest in novel antimicrobial peptides (AMP). Here, we show that the synthetic AMP-dendrimer G3KL (MW 4,531.38 Da, 15 positive charges, MIC = 8 mg/liter) showed faster killing than polymyxin B (Pmx-B) with no detectable resistance selection in P. aeruginosa strain PA14. Spontaneous mutants selected on Pmx-B, harboring loss of function mutations in the PhoQ sensor kinase gene, showed increased Pmx-B MICs and arnB operon expression (4-amino-l-arabinose addition to lipid A), but remained susceptible to dendrimers. Two mutants carrying a missense mutation in the periplasmic loop of the PmrB sensor kinase showed increased MICs for Pmx-B (8-fold) and G3KL (4-fold) but not for the dendrimer T7 (MW 4,885.64 Da, 16 positive charges, MIC = 8 mg/liter). The pmrB mutants showed increased expression of the arnB operon as well as of the speD2-speE2-PA4775 operon, located upstream of pmrAB, and involved in polyamine biosynthesis. Exogenous supplementation with the polyamines spermine and norspermine increased G3KL and T7 MICs in a phoQ mutant background but not in the PA14 wild type. This suggests that both addition of 4-amino-l-arabinose and secretion of polyamines are required to reduce susceptibility to dendrimers, probably neutralizing the negative charges present on the lipid A and the 2-keto-3-deoxyoctulosonic acid (KDO) sugars of the lipopolysaccharide (LPS), respectively. We further show by transcriptome analysis that the dendrimers G3KL and T7 induce adaptive responses through the CprRS two-component system in PA14.
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24
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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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Maisetta G, Grassi L, Esin S, Kaya E, Morelli A, Puppi D, Piras M, Chiellini F, Pifferi M, Batoni G. Targeting Pseudomonas aeruginosa in the Sputum of Primary Ciliary Dyskinesia Patients with a Combinatorial Strategy Having Antibacterial and Anti-Virulence Potential. Int J Mol Sci 2019; 21:ijms21010069. [PMID: 31861859 PMCID: PMC6981532 DOI: 10.3390/ijms21010069] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/16/2022] Open
Abstract
In primary ciliary dyskinesia (PCD) patients, Pseudomonas aeruginosa is a major opportunistic pathogen, frequently involved in chronic infections of the lower airways. Infections by this bacterial species correlates with a worsening clinical prognosis and recalcitrance to currently available therapeutics. The antimicrobial peptide, lin-SB056-1, in combination with the cation chelator ethylenediaminetetraacetic acid (EDTA), was previously demonstrated to be bactericidal against P. aeruginosa in an artificial sputum medium. The purpose of this study was to validate the anti-P. aeruginosa activity of such a combination in PCD sputum and to evaluate the in vitro anti-virulence effects of EDTA. In combination with EDTA, lin-SB056-1 was able to significantly reduce the load of endogenous P. aeruginosa ex vivo in the sputum of PCD patients. In addition, EDTA markedly reduced the production of relevant bacterial virulence factors (e.g., pyocyanin, proteases, LasA) in vitro by two representative mucoid strains of P. aeruginosa isolated from the sputum of PCD patients. These results indicate that the lin-SB056-1/EDTA combination may exert a dual antimicrobial and anti-virulence action against P. aeruginosa, suggesting a therapeutic potential against chronic airway infections sustained by this bacterium.
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Affiliation(s)
- Giuseppantonio Maisetta
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56123 Pisa, Italy; (L.G.); (S.E.); (E.K.); (G.B.)
- Correspondence: ; Tel.: +39-050-2213692; Fax: +39-050-2213711
| | - Lucia Grassi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56123 Pisa, Italy; (L.G.); (S.E.); (E.K.); (G.B.)
| | - Semih Esin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56123 Pisa, Italy; (L.G.); (S.E.); (E.K.); (G.B.)
| | - Esingül Kaya
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56123 Pisa, Italy; (L.G.); (S.E.); (E.K.); (G.B.)
| | - Andrea Morelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy; (A.M.); (D.P.); (F.C.)
| | - Dario Puppi
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy; (A.M.); (D.P.); (F.C.)
| | - Martina Piras
- Section of Pneumology and Allergology, Unit of Pediatrics, Pisa University Hospital, 56126 Pisa, Italy; (M.P.); (M.P.)
| | - Federica Chiellini
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy; (A.M.); (D.P.); (F.C.)
| | - Massimo Pifferi
- Section of Pneumology and Allergology, Unit of Pediatrics, Pisa University Hospital, 56126 Pisa, Italy; (M.P.); (M.P.)
| | - Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56123 Pisa, Italy; (L.G.); (S.E.); (E.K.); (G.B.)
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Wang T, Flint S, Palmer J. Magnesium and calcium ions: roles in bacterial cell attachment and biofilm structure maturation. BIOFOULING 2019; 35:959-974. [PMID: 31687841 DOI: 10.1080/08927014.2019.1674811] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
The ubiquitous divalent cations magnesium and calcium are important nutrients required by bacteria for growth and cell maintenance. Multi-faceted roles are shown both in bacterial initial attachment and biofilm maturation. The effects of calcium and magnesium can be highlighted in physio-chemical interactions, gene regulation and bio-macromolecular structural modification, which lead to either promotion or inhibition of biofilms. This review outlines recent research addressing phenotypic changes and mechanisms undertaken by calcium and magnesium in affecting bacterial biofilm formation.
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Affiliation(s)
- Tianyang Wang
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
| | - Steve Flint
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
| | - Jon Palmer
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
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27
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Moretti C, Trabalza S, Granieri L, Caballo‐Ponce E, Devescovi G, Del Pino AM, Ramos C, Venturi V, van den Burg HA, Buonaurio R, Palmerini CA. A Na + /Ca 2+ exchanger of the olive pathogen Pseudomonas savastanoi pv. savastanoi is critical for its virulence. MOLECULAR PLANT PATHOLOGY 2019; 20:716-730. [PMID: 30912619 PMCID: PMC6637891 DOI: 10.1111/mpp.12787] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In a number of compatible plant-bacterium interactions, a rise in apoplastic Ca2+ levels is observed, suggesting that Ca2+ represents an important environmental clue, as reported for bacteria infecting mammalians. We demonstrate that Ca2+ entry in Pseudomonas savastanoi pv. savastanoi (Psav) strain DAPP-PG 722 is mediated by a Na+ /Ca2+ exchanger critical for virulence. Using the fluorescent Ca2+ probe Fura 2-AM, we demonstrate that Ca2+ enters Psav cells foremost when they experience low levels of energy, a situation mimicking the apoplastic fluid. In fact, Ca2+ entry was suppressed in the presence of high concentrations of glucose, fructose, sucrose or adenosine triphosphate (ATP). Since Ca2+ entry was inhibited by nifedipine and LiCl, we conclude that the channel for Ca2+ entry is a Na+ /Ca2+ exchanger. In silico analysis of the Psav DAPP-PG 722 genome revealed the presence of a single gene coding for a Na+ /Ca2+ exchanger (cneA), which is a widely conserved and ancestral gene within the P. syringae complex based on gene phylogeny. Mutation of cneA compromised not only Ca2+ entry, but also compromised the Hypersensitive response (HR) in tobacco leaves and blocked the ability to induce knots in olive stems. The expression of both pathogenicity (hrpL, hrpA and iaaM) and virulence (ptz) genes was reduced in this Psav-cneA mutant. Complementation of the Psav-cneA mutation restored both Ca2+ entry and pathogenicity in olive plants, but failed to restore the HR in tobacco leaves. In conclusion, Ca2+ entry acts as a 'host signal' that allows and promotes Psav pathogenicity on olive plants.
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Affiliation(s)
- Chiaraluce Moretti
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
| | - Simone Trabalza
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
| | - Letizia Granieri
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
| | - Eloy Caballo‐Ponce
- Instituto de Hortofruticultura Subtropical y Mediterránea La MayoraUniversidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMACSIC)Área de GenéticaMálagaSpain
| | - Giulia Devescovi
- Bacteriology Group, International Centre for Genetic Engineering and BiotechnologyTriesteItaly
| | - Alberto Marco Del Pino
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
| | - Cayo Ramos
- Bacteriology Group, International Centre for Genetic Engineering and BiotechnologyTriesteItaly
| | - Vittorio Venturi
- Bacteriology Group, International Centre for Genetic Engineering and BiotechnologyTriesteItaly
| | - Harrold A. van den Burg
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences (SILS)University of AmsterdamAmsterdamNetherlands
| | - Roberto Buonaurio
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
| | - Carlo Alberto Palmerini
- Department of Agricultural, Food and Environmental ScienceUniversity of PerugiaBorgo XX Giugno 74, Perugia06121Italy
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28
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Prevention of Surface-Associated Calcium Phosphate by the Pseudomonas syringae Two-Component System CvsSR. J Bacteriol 2019; 201:JB.00584-18. [PMID: 30617243 DOI: 10.1128/jb.00584-18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 01/03/2019] [Indexed: 12/21/2022] Open
Abstract
CvsSR is a Ca2+-induced two-component system (TCS) in the plant pathogen Pseudomonas syringae pv. tomato DC3000. Here, we discovered that CvsSR is induced by Fe3+, Zn2+, and Cd2+ However, only supplementation of Ca2+ to medium resulted in rugose, opaque colonies in ΔcvsS and ΔcvsR strains. This phenotype corresponded to formation of calcium phosphate precipitation on the surface of ΔcvsS and ΔcvsR colonies. CvsSR regulated swarming motility in P. syringae pv. tomato in a Ca2+-dependent manner, but swarming behavior was not influenced by Fe3+, Zn2+, or Cd2+ We hypothesized that reduced swarming displayed by ΔcvsS and ΔcvsR strains was due to precipitation of calcium phosphate on the surface of ΔcvsS and ΔcvsR cells grown on agar medium supplemented with Ca2+ By reducing the initial pH or adding glucose to the medium, calcium precipitation was inhibited, and swarming was restored to ΔcvsS and ΔcvsR strains, suggesting that calcium precipitation influences swarming ability. Constitutive expression of a CvsSR-regulated carbonic anhydrase and a CvsSR-regulated putative sulfate major facilitator superfamily transporter in ΔcvsS and ΔcvsR strains inhibited formation of calcium precipitates and restored the ability of ΔcvsS and ΔcvsR bacteria to swarm. Lastly, we found that glucose inhibited Ca2+-based induction of CvsSR. Hence, CvsSR is a key regulator that controls calcium precipitation on the surface of bacterial cells.IMPORTANCE Bacteria are capable of precipitating and dissolving minerals. We previously reported the characterization of the two-component system CvsSR in the plant-pathogenic bacterium Pseudomonas syringae CvsSR responds to the presence of calcium and is important for causing disease. Here, we show that CvsSR controls the ability of the bacterium to prevent calcium phosphate precipitation on the surface of cells. We also identified a carbonic anhydrase and transporter that modulate formation of surface-associated calcium precipitates. Furthermore, our results demonstrate that the ability of the bacterium to swarm is controlled by the formation and dissolution of calcium precipitates on the surface of cells. Our study describes new mechanisms for microbially induced mineralization and provides insights into the role of mineral deposits on bacterial physiology. The discoveries may lead to new technological and environmental applications.
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29
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Akiyama T, Williamson KS, Franklin MJ. Expression and regulation of the Pseudomonas aeruginosa hibernation promoting factor. Mol Microbiol 2018; 110:161-175. [PMID: 29885070 DOI: 10.1111/mmi.14001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2018] [Indexed: 12/01/2022]
Abstract
Bacterial biofilms contain subpopulations of cells that are dormant and highly tolerant to antibiotics. While dormant, the bacteria must maintain the integrity of macromolecules required for resuscitation. Previously, we showed that hibernation promoting factor (HPF) is essential for protecting Pseudomonas aeruginosa from ribosomal loss during dormancy. In this study, we mapped the genetic components required for hpf expression. Using 5'-RACE and fluorescent protein reporter fusions, we show that hpf is expressed as part of the rpoN operon, but that hpf also has a second promoter (Phpf ) within the rpoN gene. Phpf is active when the cells enter stationary phase, and expression from Phpf is modulated, but not eliminated, in mutant strains impaired in stationary phase transition (ΔdksA2, ΔrpoS and ΔrelA/ΔspoT mutants). The results of reporter gene studies and mRNA folding predictions indicated that the 5' end of the hpf mRNA may also influence hpf expression. Mutations that opened or that stabilized the mRNA hairpin loop structures strongly influenced the amount of HPF produced. The results demonstrate that hpf is expressed independently of rpoN, and that hpf regulation includes both transcriptional and post-transcriptional processes, allowing the cells to produce sufficient HPF during stationary phase to maintain viability while dormant.
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Affiliation(s)
- Tatsuya Akiyama
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Kerry S Williamson
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Michael J Franklin
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
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30
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Gulyuk AV, LaJeunesse DR, Collazo R, Ivanisevic A. Characterization of Pseudomonas aeruginosa Films on Different Inorganic Surfaces before and after UV Light Exposure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10806-10815. [PMID: 30122052 DOI: 10.1021/acs.langmuir.8b02079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The changes of the surface properties of Au, GaN, and SiO x after UV light irradiation were used to actively influence the process of formation of Pseudomonas aeruginosa films. The interfacial properties of the substrates were characterized by X-ray photoelectron spectroscopy and atomic force microscopy. The changes in the P. aeruginosa film properties were accessed by analyzing adhesion force maps and quantifying the intracellular Ca2+ concentration. The collected analysis indicates that the alteration of the inorganic materials' surface chemistry can lead to differences in biofilm formation and variable response from P. aeruginosa cells.
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Affiliation(s)
- Alexey V Gulyuk
- Department of Materials Science and Engineering , North Carolina State University , Raleigh , North Carolina 27695 , United States
| | - Dennis R LaJeunesse
- Joint School of Nanoscience and Nanoengineering , University of North Carolina-Greensboro and North Carolina A&T State University , Greensboro , North Carolina 27401 , United States
| | - Ramon Collazo
- Department of Materials Science and Engineering , North Carolina State University , Raleigh , North Carolina 27695 , United States
| | - Albena Ivanisevic
- Department of Materials Science and Engineering , North Carolina State University , Raleigh , North Carolina 27695 , United States
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31
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Ca 2+-Induced Two-Component System CvsSR Regulates the Type III Secretion System and the Extracytoplasmic Function Sigma Factor AlgU in Pseudomonas syringae pv. tomato DC3000. J Bacteriol 2018; 200:JB.00538-17. [PMID: 29263098 DOI: 10.1128/jb.00538-17] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/12/2017] [Indexed: 11/20/2022] Open
Abstract
Two-component systems (TCSs) of bacteria regulate many different aspects of the bacterial life cycle, including pathogenesis. Most TCSs remain uncharacterized, with no information about the signal(s) or regulatory targets and/or role in bacterial pathogenesis. Here, we characterized a TCS in the plant-pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 composed of the histidine kinase CvsS and the response regulator CvsR. CvsSR is necessary for virulence of P. syringae pv. tomato DC3000, since ΔcvsS and ΔcvsR strains produced fewer symptoms than the wild type (WT) and demonstrated reduced growth on multiple hosts. We discovered that expression of cvsSR is induced by Ca2+ concentrations found in leaf apoplastic fluid. Thus, Ca2+ can be added to the list of signals that promote pathogenesis of P. syringae pv. tomato DC3000 during host colonization. Through chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) and global transcriptome analysis (RNA-seq), we discerned the CvsR regulon. CvsR directly activated expression of the type III secretion system regulators, hrpR and hrpS, that regulate P. syringae pv. tomato DC3000 virulence in a type III secretion system-dependent manner. CvsR also indirectly repressed transcription of the extracytoplasmic sigma factor algU and production of alginate. Phenotypic analysis determined that CvsSR inversely regulated biofilm formation, swarming motility, and cellulose production in a Ca2+-dependent manner. Overall, our results show that CvsSR is a key regulatory hub critical for interaction with host plants.IMPORTANCE Pathogenic bacteria must be able to react and respond to the surrounding environment, make use of available resources, and avert or counter host immune responses. Often, these abilities rely on two-component systems (TCSs) composed of interacting proteins that modulate gene expression. We identified a TCS in the plant-pathogenic bacterium Pseudomonas syringae that responds to the presence of calcium, which is an important signal during the plant defense response. We showed that when P. syringae is grown in the presence of calcium, this TCS regulates expression of factors contributing to disease. Overall, our results provide a better understanding of how bacterial pathogens respond to plant signals and control systems necessary for eliciting disease.
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32
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Lorè NI, Veraldi N, Riva C, Sipione B, Spagnuolo L, De Fino I, Melessike M, Calzi E, Bragonzi A, Naggi A, Cigana C. Synthesized Heparan Sulfate Competitors Attenuate Pseudomonas aeruginosa Lung Infection. Int J Mol Sci 2018; 19:ijms19010207. [PMID: 29315274 PMCID: PMC5796156 DOI: 10.3390/ijms19010207] [Citation(s) in RCA: 6] [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: 11/30/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 12/19/2022] Open
Abstract
Several chronic respiratory diseases are characterized by recurrent and/or persistent infections, chronic inflammatory responses and tissue remodeling, including increased levels of glycosaminoglycans which are known structural components of the airways. Among glycosaminoglycans, heparan sulfate (HS) has been suggested to contribute to excessive inflammatory responses. Here, we aim at (i) investigating whether long-term infection by Pseudomonas aeruginosa, one of the most worrisome threat in chronic respiratory diseases, may impact HS levels, and (ii) exploring HS competitors as potential anti-inflammatory drugs during P. aeruginosa pneumonia. P. aeruginosa clinical strains and ad-hoc synthesized HS competitors were used in vitro and in murine models of lung infection. During long-term chronic P. aeruginosa colonization, infected mice showed higher heparin/HS levels, evaluated by high performance liquid chromatography-mass spectrometry after selective enzymatic digestion, compared to uninfected mice. Among HS competitors, an N-acetyl heparin and a glycol-split heparin dampened leukocyte recruitment and cytokine/chemokine production induced by acute and chronic P. aeruginosa pneumonia in mice. Furthermore, treatment with HS competitors reduced bacterial burden during chronic murine lung infection. In vitro, P. aeruginosa biofilm formation decreased upon treatment with HS competitors. Overall, these findings support further evaluation of HS competitors as a novel therapy to counteract inflammation and infection during P. aeruginosa pneumonia.
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Affiliation(s)
- Nicola Ivan Lorè
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
- Vita-Salute San Raffaele University, Milano 20132, Italy.
| | - Noemi Veraldi
- Istituto di Ricerche Chimiche e Biochimiche "G. Ronzoni", Milano 20133, Italy.
| | - Camilla Riva
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Barbara Sipione
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Lorenza Spagnuolo
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Ida De Fino
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Medede Melessike
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Elisa Calzi
- Istituto di Ricerche Chimiche e Biochimiche "G. Ronzoni", Milano 20133, Italy.
| | - Alessandra Bragonzi
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
| | - Annamaria Naggi
- Istituto di Ricerche Chimiche e Biochimiche "G. Ronzoni", Milano 20133, Italy.
| | - Cristina Cigana
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano 20132, Italy.
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33
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Francis VI, Stevenson EC, Porter SL. Two-component systems required for virulence in Pseudomonas aeruginosa. FEMS Microbiol Lett 2018; 364:3828290. [PMID: 28510688 PMCID: PMC5812489 DOI: 10.1093/femsle/fnx104] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 05/15/2017] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa is a versatile opportunistic pathogen capable of infecting a broad range of hosts, in addition to thriving in a broad range of environmental conditions outside of hosts. With this versatility comes the need to tightly regulate its genome to optimise its gene expression and behaviour to the prevailing conditions. Two-component systems (TCSs) comprising sensor kinases and response regulators play a major role in this regulation. This minireview discusses the growing number of TCSs that have been implicated in the virulence of P. aeruginosa, with a special focus on the emerging theme of multikinase networks, which are networks comprising multiple sensor kinases working together, sensing and integrating multiple signals to decide upon the best response. The networks covered in depth regulate processes such as the switch between acute and chronic virulence (GacS network), the Cup fimbriae (Roc network and Rcs/Pvr network), the aminoarabinose modification of lipopolysaccharide (a network involving the PhoQP and PmrBA TCSs), twitching motility and virulence (a network formed from the Chp chemosensory pathway and the FimS/AlgR TCS), and biofilm formation (Wsp chemosensory pathway). In addition, we highlight the important interfaces between these systems and secondary messenger signals such as cAMP and c-di-GMP.
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Affiliation(s)
- Vanessa I Francis
- Biosciences, Geoffrey Pope Building, College of Life and Environmental Sciences, University of Exeter, Exeter EX 4QD, UK
| | - Emma C Stevenson
- Biosciences, Geoffrey Pope Building, College of Life and Environmental Sciences, University of Exeter, Exeter EX 4QD, UK
| | - Steven L Porter
- Biosciences, Geoffrey Pope Building, College of Life and Environmental Sciences, University of Exeter, Exeter EX 4QD, UK
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34
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Chevalier S, Bouffartigues E, Bodilis J, Maillot O, Lesouhaitier O, Feuilloley MGJ, Orange N, Dufour A, Cornelis P. Structure, function and regulation of Pseudomonas aeruginosa porins. FEMS Microbiol Rev 2017; 41:698-722. [PMID: 28981745 DOI: 10.1093/femsre/fux020] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/24/2017] [Indexed: 12/11/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium belonging to the γ-proteobacteria. Like other members of the Pseudomonas genus, it is known for its metabolic versatility and its ability to colonize a wide range of ecological niches, such as rhizosphere, water environments and animal hosts, including humans where it can cause severe infections. Another particularity of P. aeruginosa is its high intrinsic resistance to antiseptics and antibiotics, which is partly due to its low outer membrane permeability. In contrast to Enterobacteria, pseudomonads do not possess general diffusion porins in their outer membrane, but rather express specific channel proteins for the uptake of different nutrients. The major outer membrane 'porin', OprF, has been extensively investigated, and displays structural, adhesion and signaling functions while its role in the diffusion of nutrients is still under discussion. Other porins include OprB and OprB2 for the diffusion of glucose, the two small outer membrane proteins OprG and OprH, and the two porins involved in phosphate/pyrophosphate uptake, OprP and OprO. The remaining nineteen porins belong to the so-called OprD (Occ) family, which is further split into two subfamilies termed OccD (8 members) and OccK (11 members). In the past years, a large amount of information concerning the structure, function and regulation of these porins has been published, justifying why an updated review is timely.
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Affiliation(s)
- Sylvie Chevalier
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Emeline Bouffartigues
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Josselin Bodilis
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Olivier Maillot
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Olivier Lesouhaitier
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Marc G J Feuilloley
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Nicole Orange
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
| | - Alain Dufour
- IUEM, Laboratoire de Biotechnologie et Chimie Marines EA 3884, Université de Bretagne-Sud (UEB), 56321 Lorient, France
| | - Pierre Cornelis
- Laboratory of Microbiology Signals and Microenvironment LMSM EA 4312, University of Rouen, Normandy University, 27000 Evreux, France
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35
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Resuscitation of Pseudomonas aeruginosa from dormancy requires hibernation promoting factor (PA4463) for ribosome preservation. Proc Natl Acad Sci U S A 2017; 114:3204-3209. [PMID: 28270601 DOI: 10.1073/pnas.1700695114] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pseudomonas aeruginosa biofilm infections are difficult to treat with antibiotic therapy in part because the biofilms contain subpopulations of dormant antibiotic-tolerant cells. The dormant cells can repopulate the biofilms following alleviation of antibiotic treatments. While dormant, the bacteria must maintain cellular integrity, including ribosome abundance, to reinitiate the de novo protein synthesis required for resuscitation. Here, we demonstrate that the P. aeruginosa gene PA4463 [hibernation promoting factor (HPF)], but not the ribosome modulation factor (PA3049), is required for ribosomal RNA preservation during prolonged nutrient starvation conditions. Single-cell-level studies using fluorescence in situ hybridization (FISH) and growth in microfluidic drops demonstrate that, in the absence of hpf, the rRNA abundances of starved cells decrease to levels that cause them to lose their ability to resuscitate from starvation, leaving intact nondividing cells. P. aeruginosa defective in the stringent response also had reduced ability to resuscitate from dormancy. However, FISH analysis of the starved stringent response mutant showed a bimodal response where the individual cells contained either abundant or low ribosome content, compared with the wild-type strain. The results indicate that ribosome maintenance is key for maintaining the ability of P. aeruginosa to resuscitate from starvation-induced dormancy and that HPF is the major factor associated with P. aeruginosa ribosome preservation.
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36
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Schroeder M, Brooks BD, Brooks AE. The Complex Relationship between Virulence and Antibiotic Resistance. Genes (Basel) 2017; 8:E39. [PMID: 28106797 PMCID: PMC5295033 DOI: 10.3390/genes8010039] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/21/2016] [Accepted: 01/07/2017] [Indexed: 12/17/2022] Open
Abstract
Antibiotic resistance, prompted by the overuse of antimicrobial agents, may arise from a variety of mechanisms, particularly horizontal gene transfer of virulence and antibiotic resistance genes, which is often facilitated by biofilm formation. The importance of phenotypic changes seen in a biofilm, which lead to genotypic alterations, cannot be overstated. Irrespective of if the biofilm is single microbe or polymicrobial, bacteria, protected within a biofilm from the external environment, communicate through signal transduction pathways (e.g., quorum sensing or two-component systems), leading to global changes in gene expression, enhancing virulence, and expediting the acquisition of antibiotic resistance. Thus, one must examine a genetic change in virulence and resistance not only in the context of the biofilm but also as inextricably linked pathologies. Observationally, it is clear that increased virulence and the advent of antibiotic resistance often arise almost simultaneously; however, their genetic connection has been relatively ignored. Although the complexities of genetic regulation in a multispecies community may obscure a causative relationship, uncovering key genetic interactions between virulence and resistance in biofilm bacteria is essential to identifying new druggable targets, ultimately providing a drug discovery and development pathway to improve treatment options for chronic and recurring infection.
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Affiliation(s)
- Meredith Schroeder
- Department of Microbiological Sciences; North Dakota State University, Fargo, ND 58105, USA.
| | - Benjamin D Brooks
- Department of Electrical and Computer Engineering; North Dakota State University, Fargo, ND 58105, USA.
| | - Amanda E Brooks
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND 58105, USA.
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Khanam S, Guragain M, Lenaburg DL, Kubat R, Patrauchan MA. Calcium induces tobramycin resistance in Pseudomonas aeruginosa by regulating RND efflux pumps. Cell Calcium 2016; 61:32-43. [PMID: 28034459 DOI: 10.1016/j.ceca.2016.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/27/2016] [Accepted: 11/17/2016] [Indexed: 11/24/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic multidrug resistant pathogen causing severe chronic infections. Our previous studies showed that elevated calcium (Ca2+) enhances production of several virulence factors and plant infectivity of the pathogen. Here we show that Ca2+ increases resistance of P. aeruginosa PAO1 to tobramycin, antibiotic commonly used to treat Pseudomonas infections. LC-MS/MS-based comparative analysis of the membrane proteomes of P aeruginosa grown at elevated versus not added Ca2+, determined that the abundances of two RND (resistance-nodulation-cell division) efflux pumps, MexAB-OprM and MexVW-OprM, were increased in the presence of elevated Ca2+. Analysis of twelve transposon mutants with disrupted RND efflux pumps showed that six of them (mexB, muxC, mexY, mexJ, czcB, and mexE) contribute to Ca2+-induced tobramycin resistance. Transcriptional analyses by promoter activity and RT-qPCR showed that the expression of mexAB, muxABC, mexXY, mexJK, czcCBA, and mexVW is increased by elevated Ca2+. Disruption of mexJ, mexC, mexI, and triA significantly decreased Ca2+-induced plant infectivity of the pathogen. Earlier, our group showed that PAO1 maintains intracellular Ca2+ (Ca2+in) homeostasis, which mediates Ca2+ regulation of P. aeruginosa virulence, and identified four putative Ca2+ transporters involved in this process (Guragain et al., 2013). Here we show that three of these transporters (PA2435, PA2092, PA4614) play role in Ca2+-induced tobramycin resistance and one of them (PA2435) contributes to Ca2+ regulation of mexAB-oprM promoter activity. Furthermore, mexJ, czcB, and mexE contribute to the maintenance of Ca2+in homeostasis. This provides the first evidence that Ca2+in homeostasis mediates Ca2+ regulation of RND transport systems, which contribute to Ca2+-enhanced tobramycin resistance and plant infectivity in P. aeruginosa.
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Affiliation(s)
- Sharmily Khanam
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Manita Guragain
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Dirk L Lenaburg
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Ryan Kubat
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Marianna A Patrauchan
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States.
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King M, Guragain M, Sarkisova S, Patrauchan M. Pyocyanin Extraction and Quantitative Analysis in Swarming Pseudomonas aeruginosa. Bio Protoc 2016. [DOI: 10.21769/bioprotoc.2042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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