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Abril AG, Calo-Mata P, Böhme K, Villa TG, Barros-Velázquez J, Sánchez-Pérez Á, Pazos M, Carrera M. Shotgun proteomic analyses of Pseudomonas species isolated from fish products. Food Chem 2024; 450:139342. [PMID: 38631198 DOI: 10.1016/j.foodchem.2024.139342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 03/25/2024] [Accepted: 04/09/2024] [Indexed: 04/19/2024]
Abstract
Numerous Pseudomonas species can infect aquatic animals, such as farmed rainbow trout, sea trout, sea bass, and sea bream, by causing disease or stress reactions. In aquaculture facilities, a number of Pseudomonas species have been isolated and identified as the main pathogens. The present study describes the characterization of 18 Pseudomonas strains, isolated from fish products using shotgun proteomics. The bacterial proteomes obtained were further analyzed to identify the main functional pathway proteins involved. In addition, this study revealed the presence of 1015 non-redundant peptides related to virulence factors. An additional 25 species-specific peptides were identified as putative Pseudomonas spp. biomarkers. The results constitute the largest dataset, described thus far for the rapid identification and characterization of Pseudomonas species present in edible fish; furthermore, these data can provide the basis for further research into the development of new therapies against these harmful pathogens.
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Affiliation(s)
- Ana G Abril
- Department of Food Technology, Marine Research Institute (IIM-CSIC), Spanish National Research Council (CSIC), 36208 Vigo, Spain; Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15898 Santiago de Compostela, Spain.
| | - Pilar Calo-Mata
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain.
| | - Karola Böhme
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain
| | - Tomás G Villa
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, 15898 Santiago de Compostela, Spain
| | - Jorge Barros-Velázquez
- Department of Analytical Chemistry, Nutrition and Food Science, Food Technology Division, School of Veterinary Sciences, University of Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain.
| | - Ángeles Sánchez-Pérez
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW 2006, Australia
| | - Manuel Pazos
- Department of Food Technology, Marine Research Institute (IIM-CSIC), Spanish National Research Council (CSIC), 36208 Vigo, Spain.
| | - Mónica Carrera
- Department of Food Technology, Marine Research Institute (IIM-CSIC), Spanish National Research Council (CSIC), 36208 Vigo, Spain.
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2
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Chen G, Fanouraki G, Anandhi Rangarajan A, Winkelman BT, Winkelman JT, Waters CM, Mukherjee S. Combinatorial control of Pseudomonas aeruginosa biofilm development by quorum-sensing and nutrient-sensing regulators. mSystems 2024:e0037224. [PMID: 39140783 DOI: 10.1128/msystems.00372-24] [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: 03/13/2024] [Accepted: 06/23/2024] [Indexed: 08/15/2024] Open
Abstract
The human pathogen Pseudomonas aeruginosa, a leading cause of hospital-acquired infections, inhabits and forms sessile antibiotic-resistant communities called biofilms in a wide range of biotic and abiotic environments. In this study, we examined how two global sensory signaling pathways-the RhlR quorum-sensing system and the CbrA/CbrB nutritional adaptation system-intersect to control biofilm development. Previous work has shown that individually these two systems repress biofilm formation. Here, we used biofilm analyses, RNA-seq, and reporter assays to explore the combined effect of information flow through RhlR and CbrA on biofilm development. We find that the ΔrhlRΔcbrA double mutant exhibits a biofilm morphology and an associated transcriptional response distinct from wildtype and the parent ΔrhlR and ΔcbrA mutants indicating codominance of each signaling pathway. The ΔrhlRΔcbrA mutant gains suppressor mutations that allow biofilm expansion; these mutations map to the crc gene resulting in loss of function of the carbon catabolite repression protein Crc. Furthermore, the combined absence of RhlR and CbrA leads to a drastic reduction in the abundance of the Crc antagonist small RNA CrcZ. Thus, CrcZ acts as the molecular convergence point for quorum- and nutrient-sensing cues. We find that in the absence of antagonism by CrcZ, Crc promotes the expression of biofilm matrix components-Pel exopolysaccharide, and CupB and CupC fimbriae. Therefore, this study uncovers a regulatory link between nutritional adaption and quorum sensing with potential implications for anti-biofilm targeting strategies.IMPORTANCEBacteria often form multicellular communities encased in an extracytoplasmic matrix called biofilms. Biofilm development is controlled by various environmental stimuli that are decoded and converted into appropriate cellular responses. To understand how information from two distinct stimuli is integrated, we used biofilm formation in the human pathogen Pseudomonas aeruginosa as a model and studied the intersection of two global sensory signaling pathways-quorum sensing and nutritional adaptation. Global transcriptomics on biofilm cells and reporter assays suggest parallel regulation of biofilms by each pathway that converges on the abundance of a small RNA antagonist of the carbon catabolite repression protein, Crc. We find a new role of Crc as it modulates the expression of biofilm matrix components in response to the environment. These results expand our understanding of the genetic regulatory strategies that allow P. aeruginosa to successfully develop biofilm communities.
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Affiliation(s)
- Gong Chen
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | - Georgia Fanouraki
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | | | | | - Jared T Winkelman
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Sampriti Mukherjee
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
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3
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Lu Y, Lu F, Zhang J, Tang Q, Yang D, Liu Y. Understanding the sources, function, and irreplaceable role of cobamides in organohalide-respiring bacteria. Front Microbiol 2024; 15:1435674. [PMID: 39139376 PMCID: PMC11321594 DOI: 10.3389/fmicb.2024.1435674] [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: 05/20/2024] [Accepted: 06/25/2024] [Indexed: 08/15/2024] Open
Abstract
Halogenated organic compounds are persistent pollutants that pose a serious threat to human health and the safety of ecosystems. Cobamides are essential cofactors for reductive dehalogenases (RDase) in organohalide-respiring bacteria (OHRB), which catalyze the dehalogenation process. This review systematically summarizes the impact of cobamides on organohalide respiration. The catalytic processes of cobamide in dehalogenation processes are also discussed. Additionally, we examine OHRB, which cannot synthesize cobamide and must obtain it from the environment through a salvage pathway; the co-culture with cobamide producer is more beneficial and possible. This review aims to help readers better understand the importance and function of cobamides in reductive dehalogenation. The presented information can aid in the development of bioremediation strategies.
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Affiliation(s)
- Yongfeng Lu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Fancheng Lu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Jian Zhang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Qianwei Tang
- College & Hospital of Stomatology, Guangxi Medical University, Nanning, China
| | - Dan Yang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
- Guangxi Yuhuacheng Environmental Protection Technology Co., Nanning, China
| | - Yaqing Liu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
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4
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Borchert AJ, Bleem AC, Lim HG, Rychel K, Dooley KD, Kellermyer ZA, Hodges TL, Palsson BO, Beckham GT. Machine learning analysis of RB-TnSeq fitness data predicts functional gene modules in Pseudomonas putida KT2440. mSystems 2024; 9:e0094223. [PMID: 38323821 PMCID: PMC10949508 DOI: 10.1128/msystems.00942-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 01/07/2024] [Indexed: 02/08/2024] Open
Abstract
There is growing interest in engineering Pseudomonas putida KT2440 as a microbial chassis for the conversion of renewable and waste-based feedstocks, and metabolic engineering of P. putida relies on the understanding of the functional relationships between genes. In this work, independent component analysis (ICA) was applied to a compendium of existing fitness data from randomly barcoded transposon insertion sequencing (RB-TnSeq) of P. putida KT2440 grown in 179 unique experimental conditions. ICA identified 84 independent groups of genes, which we call fModules ("functional modules"), where gene members displayed shared functional influence in a specific cellular process. This machine learning-based approach both successfully recapitulated previously characterized functional relationships and established hitherto unknown associations between genes. Selected gene members from fModules for hydroxycinnamate metabolism and stress resistance, acetyl coenzyme A assimilation, and nitrogen metabolism were validated with engineered mutants of P. putida. Additionally, functional gene clusters from ICA of RB-TnSeq data sets were compared with regulatory gene clusters from prior ICA of RNAseq data sets to draw connections between gene regulation and function. Because ICA profiles the functional role of several distinct gene networks simultaneously, it can reduce the time required to annotate gene function relative to manual curation of RB-TnSeq data sets. IMPORTANCE This study demonstrates a rapid, automated approach for elucidating functional modules within complex genetic networks. While Pseudomonas putida randomly barcoded transposon insertion sequencing data were used as a proof of concept, this approach is applicable to any organism with existing functional genomics data sets and may serve as a useful tool for many valuable applications, such as guiding metabolic engineering efforts in other microbes or understanding functional relationships between virulence-associated genes in pathogenic microbes. Furthermore, this work demonstrates that comparison of data obtained from independent component analysis of transcriptomics and gene fitness datasets can elucidate regulatory-functional relationships between genes, which may have utility in a variety of applications, such as metabolic modeling, strain engineering, or identification of antimicrobial drug targets.
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Affiliation(s)
- Andrew J. Borchert
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Alissa C. Bleem
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Hyun Gyu Lim
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Joint BioEnergy Institute, Emeryville, California, USA
- Department of Biological Engineering, Inha University, Incheon, Korea
| | - Kevin Rychel
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Keven D. Dooley
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Zoe A. Kellermyer
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Tracy L. Hodges
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Bernhard O. Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Joint BioEnergy Institute, Emeryville, California, USA
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
- Department of Pediatrics, University of California, San Diego, California, USA
| | - Gregg T. Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Agile BioFoundry, Emeryville, California, USA
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5
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Moreno R, Rojo F. What are the signals that control catabolite repression in Pseudomonas? Microb Biotechnol 2024; 17:e14407. [PMID: 38227132 PMCID: PMC10832556 DOI: 10.1111/1751-7915.14407] [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: 11/17/2023] [Revised: 12/29/2023] [Accepted: 01/02/2024] [Indexed: 01/17/2024] Open
Abstract
Metabolically versatile bacteria exhibit a global regulatory response known as carbon catabolite repression (CCR), which prioritizes some carbon sources over others when all are present in sufficient amounts. This optimizes growth by distributing metabolite fluxes, but can restrict yields in biotechnological applications. The molecular mechanisms and preferred substrates for CCR vary between bacterial groups. Escherichia coli prioritizes glucose whereas Pseudomonas sp. prefer certain organic acids or amino acids. A significant issue in understanding (and potentially bypassing) CCR is the lack of information about the signals that trigger this regulatory response. In E. coli, several key compounds act as flux sensors, governing the flow of metabolites through catabolic pathways and preventing imbalances. These flux sensors can also modulate the CCR response. It has been suggested that the order of substrate preference is determined by carbon uptake flux rather than substrate identity. For Pseudomonas, much less information is available, as the signals that induce CCR are poorly understood. This article briefly discusses the available evidence on the signals that trigger CCR and the questions that remain to be answered in Pseudomonas.
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Affiliation(s)
- Renata Moreno
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología, CSICMadridSpain
| | - Fernando Rojo
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología, CSICMadridSpain
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6
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Mutyala S, Kim JR. Recent advances and challenges in the bioconversion of acetate to value-added chemicals. BIORESOURCE TECHNOLOGY 2022; 364:128064. [PMID: 36195215 DOI: 10.1016/j.biortech.2022.128064] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
Acetate is a major byproduct of the bioconversion of the greenhouse gas carbon dioxide, pretreatment of lignocellulose biomass, and microbial fermentation. The utilization and valorization of acetate have been emphasized in transforming waste to clean energy and value-added platform chemicals, contributing to the development of a closed carbon loop toward a low-carbon circular bio-economy. Acetate has been used to produce several platform chemicals, including succinate, 3-hydroxypropionate, and itaconic acid, highlighting the potential of acetate to synthesize many biochemicals and biofuels. On the other hand, the yields and titers have not reached the theoretical maximum. Recently, recombinant strain development and pathway regulation have been suggested to overcome this limitation. This review provides insights into the important constraints limiting the yields and titers of the biochemical and metabolic pathways of bacteria capable of metabolizing acetate for acetate bioconversion. The current developments in recombinant strain engineering are also discussed.
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Affiliation(s)
- Sakuntala Mutyala
- School of Chemical Engineering, Pusan National University, 63 Busandeahak-ro, Geumjeong-Gu, Busan 46241, Republic of Korea
| | - Jung Rae Kim
- School of Chemical Engineering, Pusan National University, 63 Busandeahak-ro, Geumjeong-Gu, Busan 46241, Republic of Korea.
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7
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Ramos AL, Aquino M, García G, Gaspar M, de la Cruz C, Saavedra-Flores A, Brom S, Cervantes-Rivera R, Galindo-Sánchez CE, Hernandez R, Puhar A, Lupas AN, Sepulveda E. RpuS/R Is a Novel Two-Component Signal Transduction System That Regulates the Expression of the Pyruvate Symporter MctP in Sinorhizobium fredii NGR234. Front Microbiol 2022; 13:871077. [PMID: 35572670 PMCID: PMC9100948 DOI: 10.3389/fmicb.2022.871077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/11/2022] [Indexed: 11/16/2022] Open
Abstract
The SLC5/STAC histidine kinases comprise a recently identified family of sensor proteins in two-component signal transduction systems (TCSTS), in which the signaling domain is fused to an SLC5 solute symporter domain through a STAC domain. Only two members of this family have been characterized experimentally, the CrbS/R system that regulates acetate utilization in Vibrio and Pseudomonas, and the CbrA/B system that regulates the utilization of histidine in Pseudomonas and glucose in Azotobacter. In an attempt to expand the characterized members of this family beyond the Gammaproteobacteria, we identified two putative TCSTS in the Alphaproteobacterium Sinorhizobium fredii NGR234 whose sensor histidine kinases belong to the SLC5/STAC family. Using reverse genetics, we were able to identify the first TCSTS as a CrbS/R homolog that is also needed for growth on acetate, while the second TCSTS, RpuS/R, is a novel system required for optimal growth on pyruvate. Using RNAseq and transcriptional fusions, we determined that in S. fredii the RpuS/R system upregulates the expression of an operon coding for the pyruvate symporter MctP when pyruvate is the sole carbon source. In addition, we identified a conserved DNA sequence motif in the putative promoter region of the mctP operon that is essential for the RpuR-mediated transcriptional activation of genes under pyruvate-utilizing conditions. Finally, we show that S. fredii mutants lacking these TCSTS are affected in nodulation, producing fewer nodules than the parent strain and at a slower rate.
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Affiliation(s)
| | - Maria Aquino
- Facultad de Ciencias, Universidad Autónoma de Baja California, Ensenada, Mexico
| | - Gema García
- Facultad de Biología, Universidad Autónoma de Sinaloa, Culiacan, Mexico
| | - Miriam Gaspar
- Facultad de Ciencias, Universidad Autónoma de Baja California, Ensenada, Mexico
| | - Cristina de la Cruz
- Programa de Ingeniería Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Anaid Saavedra-Flores
- Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Susana Brom
- Programa de Ingeniería Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Ramón Cervantes-Rivera
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
- Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Clara Elizabeth Galindo-Sánchez
- Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Rufina Hernandez
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Andrea Puhar
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
- Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Andrei N. Lupas
- Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | - Edgardo Sepulveda
- CONACYT-Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Mexico
- *Correspondence: Edgardo Sepulveda,
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8
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Murphy ARJ, Scanlan DJ, Chen Y, Bending GD, Hammond JP, Wellington EMH, Lidbury IDEA. 2-aminoethylphosphonate utilisation in Pseudomonas putida BIRD-1 is controlled by multiple master regulators. Environ Microbiol 2022; 24:1902-1917. [PMID: 35229442 PMCID: PMC9311074 DOI: 10.1111/1462-2920.15959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/24/2022] [Indexed: 11/30/2022]
Abstract
Bacteria possess various regulatory mechanisms to detect and coordinate a response to elemental nutrient limitation. In pseudomonads, the two‐component system regulators CbrAB, NtrBC and PhoBR, are responsible for regulating cellular response to carbon (C), nitrogen (N) and phosphorus (P) respectively. Phosphonates are reduced organophosphorus compounds produced by a broad range of biota and typified by a direct C‐P bond. Numerous pseudomonads can use the environmentally abundant phosphonate species 2‐aminoethylphosphonate (2AEP) as a source of C, N, or P, but only PhoBR has been shown to play a role in 2AEP utilization. On the other hand, utilization of 2AEP as a C and N source is considered substrate inducible. Here, using the plant‐growth‐promoting rhizobacterium Pseudomonas putida BIRD‐1 we present evidence that 2AEP utilization is under dual regulation and only occurs upon depletion of C, N, or P, controlled by CbrAB, NtrBC, or PhoBR respectively. However, the presence of 2AEP was necessary for full gene expression, i.e. expression was substrate inducible. Mutation of a LysR‐type regulator, termed AepR, upstream of the 2AEP transaminase‐phosphonatase system (PhnWX), confirmed this dual regulatory mechanism. To our knowledge, this is the first study identifying coordination between global stress response and substrate‐specific regulators in phosphonate metabolism.
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Affiliation(s)
- Andrew R J Murphy
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK
| | - David J Scanlan
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK
| | - Yin Chen
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK
| | - Gary D Bending
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK
| | - John P Hammond
- School of Agriculture, Policy, and Development, University of Reading, Earley Gate, Whiteknights, Reading, UK
| | | | - Ian D E A Lidbury
- Plants, Photosynthesis and Soil Research Cluster, School of Biosciences, University of Sheffield, Sheffield, UK
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9
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Monteagudo-Cascales E, Santero E, Canosa I. The Regulatory Hierarchy Following Signal Integration by the CbrAB Two-Component System: Diversity of Responses and Functions. Genes (Basel) 2022; 13:genes13020375. [PMID: 35205417 PMCID: PMC8871633 DOI: 10.3390/genes13020375] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 02/04/2023] Open
Abstract
CbrAB is a two-component system, unique to bacteria of the family Pseudomonaceae, capable of integrating signals and involved in a multitude of physiological processes that allow bacterial adaptation to a wide variety of varying environmental conditions. This regulatory system provides a great metabolic versatility that results in excellent adaptability and metabolic optimization. The two-component system (TCS) CbrA-CbrB is on top of a hierarchical regulatory cascade and interacts with other regulatory systems at different levels, resulting in a robust output. Among the regulatory systems found at the same or lower levels of CbrAB are the NtrBC nitrogen availability adaptation system, the Crc/Hfq carbon catabolite repression cascade in Pseudomonas, or interactions with the GacSA TCS or alternative sigma ECF factor, such as SigX. The interplay between regulatory mechanisms controls a number of physiological processes that intervene in important aspects of bacterial adaptation and survival. These include the hierarchy in the use of carbon sources, virulence or resistance to antibiotics, stress response or definition of the bacterial lifestyle. The multiple actions of the CbrAB TCS result in an important competitive advantage.
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Affiliation(s)
| | - Eduardo Santero
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
| | - Inés Canosa
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
- Correspondence: ; Tel.: +34-954349052
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10
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Sivakumar R, Gunasekaran P, Rajendhran J. Inactivation of CbrAB two-component system hampers root colonization in rhizospheric strain of Pseudomonas aeruginosa PGPR2. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2021; 1864:194763. [PMID: 34530138 DOI: 10.1016/j.bbagrm.2021.194763] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 11/24/2022]
Abstract
Two-component systems (TCS) are one of the signal transduction mechanisms, which sense physiological/biological restraints and respond to changing environmental conditions by regulating the gene expression. Previously, by employing a forward genetic screen (INSeq), we identified that cbrA gene is essential for the fitness of Pseudomonas aeruginosa PGPR2 during root colonization. Here, we report the functional characterization of cbrAB TCS in PGPR2 during root colonization. We constructed insertion mutants in cbrA and its cognate response regulator cbrB. Genetic characterization revealed drastic down-regultion of sRNA crcZ gene in both mutant strains which play a critical role in carbon catabolite repression (CCR). The mutant strains displayed 10-fold decreased root colonization efficiency when compared to the wild-type strain. On the other hand, mutant strains formed higher biofilm on the abiotic surface, and the expression of pelB and pslA genes involved in biofilm matrix formation was up-regulated. In contrast, the expression of algD, responsible for alginate production, and its associated sigma factor algU was significantly down-regulated in mutant strains. We further analyzed the transcript levels of rsmA, controlled by the algU sigma factor, and found that the expression of rsmA was hampered in both mutants. The ability of mutant strains to swim and swarm was significantly hindered. Also, the expression of genes associated with type III secretion system (T3SS) was dysregulated in mutant strains. Taken together, regulation of gene expression by CbrAB TCS is intricate, and we confirm its role beyond carbon and nitrogen assimilation.
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Affiliation(s)
- Ramamoorthy Sivakumar
- Department of Genetics, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | | | - Jeyaprakash Rajendhran
- Department of Genetics, School of Biological Sciences, Madurai Kamaraj University, Madurai, India.
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11
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Involvement of the MxtR/ErdR (CrbS/CrbR) Two-Component System in Acetate Metabolism in Pseudomonas putida KT2440. Microorganisms 2021; 9:microorganisms9081558. [PMID: 34442637 PMCID: PMC8402216 DOI: 10.3390/microorganisms9081558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/16/2021] [Accepted: 07/18/2021] [Indexed: 11/20/2022] Open
Abstract
MxtR/ErdR (also called CrbS/CrbR) is a two-component system previously identified as important for the utilization of acetate in Vibrio cholerae and some Pseudomonas species. In addition, evidence has been found in Pseudomonas aeruginosa for a role in regulating the synthesis and expression, respectively, of virulence factors such as siderophores and RND transporters. In this context, we investigated the physiological role of the MxtR/ErdR system in the soil bacterium Pseudomonas putida KT2440. To that end, mxtR and erdR were individually deleted and the ability of the resulting mutants to metabolize different carbon sources was analyzed in comparison to wild type. We also assessed the impact of the deletions on siderophore production, expression of mexEF-oprN (RND transporter), and the biocontrol properties of the strain. Furthermore, the MxtR/ErdR-dependent expression of putative target genes and binding of ErdR to respective promoter regions were analyzed. Our results indicated that the MxtR/ErdR system is active and essential for acetate utilization in P. putida KT2440. Expression of scpC, pp_0354, and acsA-I was stimulated by acetate, while direct interactions of ErdR with the promoter regions of the genes scpC, pp_0354, and actP-I were demonstrated by an electromobility shift assay. Finally, our results suggested that MxtR/ErdR is neither involved in regulating siderophore production nor the expression of mexEF-oprN in P. putida KT2440 under the conditions tested.
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Naren N, Zhang XX. Role of a local transcription factor in governing cellular carbon/nitrogen homeostasis in Pseudomonas fluorescens. Nucleic Acids Res 2021; 49:3204-3216. [PMID: 33675669 PMCID: PMC8034625 DOI: 10.1093/nar/gkab091] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 12/14/2022] Open
Abstract
Autoactivation of two-component systems (TCSs) can increase the sensitivity to signals but inherently cause a delayed response. Here, we describe a unique negative feedback mechanism enabling the global NtrB/NtrC regulator to rapidly respond to nitrogen starvation over the course of histidine utilization (hut) in Pseudomonas fluorescens. NtrBC directly activates transcription of hut genes, but overexpression will produce excess ammonium leading to NtrBC inactivation. To prevent this from occurring, the histidine-responsive repressor HutC fine-tunes ntrBC autoactivation: HutC and NtrC bind to the same operator site in the ntrBC promoter. This newly discovered low-affinity binding site shows little sequence similarity with the consensus sequence that HutC recognizes for substrate-specific induction of hut operons. A combination of genetic and transcriptomic analysis indicated that both ntrBC and hut promoter activities cannot be stably maintained in the ΔhutC background when histidine fluctuates at high concentrations. Moreover, the global carbon regulator CbrA/CbrB is involved in directly activating hut transcription while de-repressing hut translation via the CbrAB-CrcYZ-Crc/Hfq regulatory cascade. Together, our data reveal that the local transcription factor HutC plays a crucial role in governing NtrBC to maintain carbon/nitrogen homeostasis through the complex interactions between two TCSs (NtrBC and CbrAB) at the hut promoter.
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Affiliation(s)
- Naran Naren
- School of Natural and Computational Sciences, Massey University at Albany, Auckland 0745, New Zealand
| | - Xue-Xian Zhang
- School of Natural and Computational Sciences, Massey University at Albany, Auckland 0745, New Zealand
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Prokaryotic Solute/Sodium Symporters: Versatile Functions and Mechanisms of a Transporter Family. Int J Mol Sci 2021; 22:ijms22041880. [PMID: 33668649 PMCID: PMC7918813 DOI: 10.3390/ijms22041880] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/02/2021] [Accepted: 02/10/2021] [Indexed: 11/23/2022] Open
Abstract
The solute/sodium symporter family (SSS family; TC 2.A.21; SLC5) consists of integral membrane proteins that use an existing sodium gradient to drive the uphill transport of various solutes, such as sugars, amino acids, vitamins, or ions across the membrane. This large family has representatives in all three kingdoms of life. The human sodium/iodide symporter (NIS) and the sodium/glucose transporter (SGLT1) are involved in diseases such as iodide transport defect or glucose-galactose malabsorption. Moreover, the bacterial sodium/proline symporter PutP and the sodium/sialic acid symporter SiaT play important roles in bacteria–host interactions. This review focuses on the physiological significance and structural and functional features of prokaryotic members of the SSS family. Special emphasis will be given to the roles and properties of proteins containing an SSS family domain fused to domains typically found in bacterial sensor kinases.
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Thompson MG, Incha MR, Pearson AN, Schmidt M, Sharpless WA, Eiben CB, Cruz-Morales P, Blake-Hedges JM, Liu Y, Adams CA, Haushalter RW, Krishna RN, Lichtner P, Blank LM, Mukhopadhyay A, Deutschbauer AM, Shih PM, Keasling JD. Fatty Acid and Alcohol Metabolism in Pseudomonas putida: Functional Analysis Using Random Barcode Transposon Sequencing. Appl Environ Microbiol 2020; 86:e01665-20. [PMID: 32826213 PMCID: PMC7580535 DOI: 10.1128/aem.01665-20] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 08/12/2020] [Indexed: 12/13/2022] Open
Abstract
With its ability to catabolize a wide variety of carbon sources and a growing engineering toolkit, Pseudomonas putida KT2440 is emerging as an important chassis organism for metabolic engineering. Despite advances in our understanding of the organism, many gaps remain in our knowledge of the genetic basis of its metabolic capabilities. The gaps are particularly noticeable in our understanding of both fatty acid and alcohol catabolism, where many paralogs putatively coding for similar enzymes coexist, making biochemical assignment via sequence homology difficult. To rapidly assign function to the enzymes responsible for these metabolisms, we leveraged random barcode transposon sequencing (RB-Tn-Seq). Global fitness analyses of transposon libraries grown on 13 fatty acids and 10 alcohols produced strong phenotypes for hundreds of genes. Fitness data from mutant pools grown on fatty acids of varying chain lengths indicated specific enzyme substrate preferences and enabled us to hypothesize that DUF1302/DUF1329 family proteins potentially function as esterases. From the data, we also postulate catabolic routes for the two biogasoline molecules isoprenol and isopentanol, which are catabolized via leucine metabolism after initial oxidation and activation with coenzyme A (CoA). Because fatty acids and alcohols may serve as both feedstocks and final products of metabolic-engineering efforts, the fitness data presented here will help guide future genomic modifications toward higher titers, rates, and yields.IMPORTANCE To engineer novel metabolic pathways into P. putida, a comprehensive understanding of the genetic basis of its versatile metabolism is essential. Here, we provide functional evidence for the putative roles of hundreds of genes involved in the fatty acid and alcohol metabolism of the bacterium. These data provide a framework facilitating precise genetic changes to prevent product degradation and to channel the flux of specific pathway intermediates as desired.
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Affiliation(s)
- Mitchell G Thompson
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant Biology, University of California, Davis, California, USA
| | - Matthew R Incha
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Allison N Pearson
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Matthias Schmidt
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany
| | - William A Sharpless
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Christopher B Eiben
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Joint Program in Bioengineering, University of California, Berkeley, California, USA
| | - Pablo Cruz-Morales
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Centro de Biotecnología FEMSA, Instituto Tecnológico y de Estudios Superiores de Monterrey, Monterrey, México
| | - Jacquelyn M Blake-Hedges
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Yuzhong Liu
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Catharine A Adams
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Robert W Haushalter
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Rohith N Krishna
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Patrick Lichtner
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Lars M Blank
- Institute of Applied Microbiology (iAMB), Aachen Biology and Biotechnology (ABBt), RWTH Aachen University, Aachen, Germany
| | - Aindrila Mukhopadhyay
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Adam M Deutschbauer
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Patrick M Shih
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Plant Biology, University of California, Davis, California, USA
- Environmental and Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Jay D Keasling
- Joint BioEnergy Institute, Emeryville, California, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Joint Program in Bioengineering, University of California, Berkeley, California, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California, USA
- Institute for Quantitative Biosciences, University of California, Berkeley, California, USA
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
- Center for Synthetic Biochemistry, Institute for Synthetic Biology, Shenzhen Institutes for Advanced Technologies, Shenzhen, China
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15
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Wirtz L, Eder M, Schipper K, Rohrer S, Jung H. Transport and kinase activities of CbrA of Pseudomonas putida KT2440. Sci Rep 2020; 10:5400. [PMID: 32214184 PMCID: PMC7096432 DOI: 10.1038/s41598-020-62337-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/10/2020] [Indexed: 12/20/2022] Open
Abstract
The CbrA/CbrB system is a two-component signal transduction system known to participate in the regulation of the cellular carbon/nitrogen balance and to play a central role in carbon catabolite repression in Pseudomonas species. CbrA is composed of a domain with similarity to proteins of the solute/sodium symporter family (SLC5) and domains typically found in bacterial sensor kinases. Here, the functional properties of the sensor kinase CbrA and its domains are analyzed at the molecular level using the system of the soil bacterium P. putida KT2440 as a model. It is demonstrated that CbrA can bind and transport L-histidine. Transport is specific for L-histidine and probably driven by an electrochemical proton gradient. The kinase domain is not required for L-histidine uptake by the SLC5 domain of CbrA, and has no significant impact on transport kinetics. Furthermore, it is shown that the histidine kinase can autophosphorylate and transfer the phosphoryl group to the response regulator CbrB. The SLC5 domain is not essential for these activities but appears to modulate the autokinase activity. A phosphatase activity of CbrA is not detected. None of the activities is significantly affected by L-histidine. The results demonstrate that CbrA functions as a L-histidine transporter and sensor kinase.
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Affiliation(s)
- Larissa Wirtz
- Division of Microbiology, Department of Biology 1, Ludwig Maximilians University Munich, D-82152, Martinsried, Germany
| | - Michelle Eder
- Division of Microbiology, Department of Biology 1, Ludwig Maximilians University Munich, D-82152, Martinsried, Germany
| | - Kerstin Schipper
- Division of Microbiology, Department of Biology 1, Ludwig Maximilians University Munich, D-82152, Martinsried, Germany.,Institute of Microbiology, Department of Biology, Heinrich-Heine-University, D-40225, Düsseldorf, Germany
| | - Stefanie Rohrer
- Division of Microbiology, Department of Biology 1, Ludwig Maximilians University Munich, D-82152, Martinsried, Germany.,Technical University of Munich, D-80333, Munich, Germany
| | - Heinrich Jung
- Division of Microbiology, Department of Biology 1, Ludwig Maximilians University Munich, D-82152, Martinsried, Germany.
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Dethlefsen S, Jäger C, Klockgether J, Schomburg D, Tümmler B. Metabolite profiling of the cold adaptation of Pseudomonas putida KT2440 and cold-sensitive mutants. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:777-783. [PMID: 31503400 DOI: 10.1111/1758-2229.12793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/02/2019] [Accepted: 09/08/2019] [Indexed: 06/10/2023]
Abstract
Free-living bacteria such as Pseudomonas putida are frequently exposed to temperature shifts and non-optimal growth conditions. We compared the transcriptome and metabolome of the cold adaptation of P. putida KT2440 and isogenic cold-sensitive transposon mutants carrying transposons in their cbrA, cbrB, pcnB, vacB, and bipA genes. Pseudomonas putida changes the mRNA expression of about 43% of all annotated open reading frames during this initial phase of cold adaptation, but only a small number of 6-93 genes were differentially expressed at 10°C between the wild-type strain and the individual mutants. The spectrum of metabolites underwent major changes during cold adaptation particularly in the mutants. Both the KT2440 strain and the mutants increased the levels of the most abundant sugars and amino acids which were more pronounced in the cold-sensitive mutants. All mutants depleted their pools for core metabolites of aromatic and sugar metabolism, but increased their pool of polar amino acids which should be advantageous to cope with the cold stress.
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Affiliation(s)
- Sarah Dethlefsen
- Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics, Clinical Research Group, Hannover Medical School, 30625, Hannover, Germany
| | - Christian Jäger
- Department of Biochemistry and Bioinformatics, Institute for Biochemistry and Biotechnology, Technische Universität Braunschweig, 38106, Braunschweig, Germany
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Jens Klockgether
- Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics, Clinical Research Group, Hannover Medical School, 30625, Hannover, Germany
| | - Dietmar Schomburg
- Department of Biochemistry and Bioinformatics, Institute for Biochemistry and Biotechnology, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Burkhard Tümmler
- Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics, Clinical Research Group, Hannover Medical School, 30625, Hannover, Germany
- Clinic for Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, 30625, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hannover, Germany
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17
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Molina L, La Rosa R, Nogales J, Rojo F. Influence of the Crc global regulator on substrate uptake rates and the distribution of metabolic fluxes in Pseudomonas putida KT2440 growing in a complete medium. Environ Microbiol 2019; 21:4446-4459. [PMID: 31595602 PMCID: PMC6900033 DOI: 10.1111/1462-2920.14812] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 09/20/2019] [Accepted: 09/26/2019] [Indexed: 12/26/2022]
Abstract
When the soil bacterium Pseudomonas putida grows in a complete medium, it prioritizes the assimilation of preferred carbon sources, optimizing its metabolism and growth. This regulatory process is orchestrated by the Crc and Hfq proteins. The present work examines the changes that occur in metabolic fluxes when the crc gene is inactivated and cells grow exponentially in LB complete medium. Analyses were performed at three different moments during exponential growth, examining the assimilation rates for the compounds present in LB, changes in the proteome, and the changes in metabolic fluxes predicted by the iJN1411 metabolic model for P. putida KT2440. During the early exponential phase, consumption rates for sugars, many organic acids and most amino acids were higher in a Crc-null strain than in the wild type, leading to an overflow of the metabolic pathways and the leakage of pyruvate and acetate. These accelerated consumption rates decreased during the mid-exponential phase, when cells mostly used sugars and alanine. At later times, pyruvate was recovered from the medium and utilized. The higher consumption rates of the Crc-null strain reduced the growth rate. The lack of the Crc/Hfq regulatory system thus led to unbalanced metabolism with poorly optimized metabolic fluxes.
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Affiliation(s)
- Lázaro Molina
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología, CSICMadridSpain
| | - Ruggero La Rosa
- Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkKgs. LyngbyDenmark
| | - Juan Nogales
- Systems Biology ProgramCentro Nacional de Biotecnología, CSICMadridSpain
| | - Fernando Rojo
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología, CSICMadridSpain
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