scholarly journals Sugar-mediated regulation of a c-di-GMP phosphodiesterase in Vibrio cholerae

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Kyoo Heo ◽  
Young-Ha Park ◽  
Kyung-Ah Lee ◽  
Joonwon Kim ◽  
Hyeong-In Ham ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
Carbon Sources ◽  
Phosphotransferase System ◽  
Host Colonization ◽  
Host Immune Responses ◽  
Gut Colonization ◽  
Host Diet ◽  
Underlying Mechanisms ◽  
Cyclic Dinucleotide

AbstractBiofilm formation protects bacteria from stresses including antibiotics and host immune responses. Carbon sources can modulate biofilm formation and host colonization in Vibrio cholerae, but the underlying mechanisms remain unclear. Here, we show that EIIAGlc, a component of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS), regulates the intracellular concentration of the cyclic dinucleotide c-di-GMP, and thus biofilm formation. The availability of preferred sugars such as glucose affects EIIAGlc phosphorylation state, which in turn modulates the interaction of EIIAGlc with a c-di-GMP phosphodiesterase (hereafter referred to as PdeS). In a Drosophila model of V. cholerae infection, sugars in the host diet regulate gut colonization in a manner dependent on the PdeS-EIIAGlc interaction. Our results shed light into the mechanisms by which some nutrients regulate biofilm formation and host colonization.

scholarly journals Mannitol and the Mannitol-Specific Enzyme IIB Subunit Activate Vibrio cholerae Biofilm Formation

2013 ◽  
Vol 79 (15) ◽  
pp. 4675-4683 ◽  
Author(s):  
Patrick Ymele-Leki ◽  
Laetitia Houot ◽  
Paula I. Watnick
Keyword(s):  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
Diarrheal Disease ◽  
Ectopic Expression ◽  
Phosphotransferase System ◽  
Content Type ◽  
Regulatory Pathways ◽  
B Subunit ◽  
Multicomponent Signal ◽  
Enzyme I

ABSTRACTVibrio choleraeis a halophilic, Gram-negative rod found in marine environments. Strains that produce cholera toxin cause the diarrheal disease cholera.V. choleraeuse a highly conserved, multicomponent signal transduction cascade known as the phosphoenolpyruvate phosphotransferase system (PTS) to regulate carbohydrate uptake and biofilm formation. Regulation of biofilm formation by the PTS is complex, involving many different regulatory pathways that incorporate distinct PTS components. The PTS consists of the general components enzyme I (EI) and histidine protein (HPr) and carbohydrate-specific enzymes II. Mannitol transport byV. choleraerequires the mannitol-specific EII (EIIMtl), which is expressed only in the presence of mannitol. Here we show that mannitol activatesV. choleraebiofilm formation and transcription of thevpsbiofilm matrix exopolysaccharide synthesis genes. This regulation is dependent on mannitol transport. However, we show that, in the absence of mannitol, ectopic expression of the B subunit of EIIMtlis sufficient to activate biofilm accumulation. Mannitol, a common compatible solute and osmoprotectant of marine organisms, is a main photosynthetic product of many algae and is secreted by algal mats. We propose that the ability ofV. choleraeto respond to environmental mannitol by forming a biofilm may play an important role in habitat selection.

scholarly journals A fructose/H+ symporter controlled by a LacI-type regulator promotes survival of pandemic Vibrio cholerae in seawater

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yutao Liu ◽  
Bin Liu ◽  
Tingting Xu ◽  
Qian Wang ◽  
Wendi Li ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Genes ◽  
Environmental Changes ◽  
Carbon Sources ◽  
Intracellular Camp ◽  
Human Intestine ◽  
Intestinal Colonization ◽  
Phosphotransferase System ◽  
Two Component System

AbstractThe bacterium Vibrio cholerae can colonize the human intestine and cause cholera, but spends much of its life cycle in seawater. The pathogen must adapt to substantial environmental changes when moving between seawater and the human intestine, including different availability of carbon sources such as fructose. Here, we use in vitro experiments as well as mouse intestinal colonization assays to study the mechanisms used by pandemic V. cholerae to adapt to these environmental changes. We show that a LacI-type regulator (FruI) and a fructose/H+ symporter (FruT) are important for fructose uptake at low fructose concentrations, as those found in seawater. FruT is downregulated by FruI, which is upregulated when O2 concentrations are low (as in the intestine) by ArcAB, a two-component system known to respond to changes in oxygen levels. As a result, the bacteria predominantly use FruT for fructose uptake under seawater conditions (low fructose, high O2), and use a known fructose phosphotransferase system (PTS, Fpr) for fructose uptake under conditions found in the intestine. PTS activity leads to reduced levels of intracellular cAMP, which in turn upregulate virulence genes. Our results indicate that the FruT/FruI system may be important for survival of pandemic V. cholerae in seawater.

scholarly journals Vibrio cholerae Phosphoenolpyruvate Phosphotransferase System Control of Carbohydrate Transport, Biofilm Formation, and Colonization of the Germfree Mouse Intestine

2010 ◽  
Vol 78 (4) ◽  
pp. 1482-1494 ◽  
Author(s):  
Laetitia Houot ◽  
Sarah Chang ◽  
Cedric Absalon ◽  
Paula I. Watnick
Keyword(s):  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
System Control ◽  
Cellular Functions ◽  
Phosphotransferase System ◽  
Germfree Mouse ◽  
Abiotic Surfaces ◽  
Carbohydrate Transport ◽  
Mouse Intestine

ABSTRACT The bacterial phosphoenolpyruvate phosphotransferase system (PTS) is a highly conserved phosphotransfer cascade whose components modulate many cellular functions in response to carbohydrate availability. Here, we further elucidate PTS control of Vibrio cholerae carbohydrate transport and activation of biofilm formation on abiotic surfaces. We then define the role of the PTS in V. cholerae colonization of the adult germfree mouse intestine. We report that V. cholerae colonizes both the small and large intestines of the mouse in a distribution that does not change over the course of a month-long experiment. Because V. cholerae possesses many PTS-independent carbohydrate transporters, the PTS is not essential for bacterial growth in vitro. However, we find that the PTS is essential for colonization of the germfree adult mouse intestine and that this requirement is independent of PTS regulation of biofilm formation. Therefore, competition for PTS substrates may be a dominant force in the success of V. cholerae as an intestinal pathogen. Because the PTS plays a role in colonization of environmental surfaces and the mammalian intestine, we propose that it may be essential to successful transit of V. cholerae through its life cycle of pathogenesis and environmental persistence.

scholarly journals Virulence and the Environment: a Novel Role for Vibrio cholerae Toxin-Coregulated Pili in Biofilm Formation on Chitin

2005 ◽  
Vol 187 (10) ◽  
pp. 3551-3555 ◽  
Author(s):  
Gemma Reguera ◽  
Roberto Kolter
Keyword(s):  
Cholera Toxin ◽  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
Intestinal Colonization ◽  
Host Colonization ◽  
Ecological Fitness ◽  
Bacterial Interactions ◽  
Colonization Factor ◽  
Selection For ◽  
Toxin Coregulated Pilus

ABSTRACT The toxin-coregulated pilus (TCP) of Vibrio cholerae is required for intestinal colonization and cholera toxin acquisition. Here we report that TCP mediates bacterial interactions required for biofilm differentiation on chitinaceous surfaces. We also show that undifferentiated TCP− biofilms have reduced ecological fitness and, thus, that chitin colonization may represent an ecological setting outside the host in which selection for a host colonization factor may take place.

scholarly journals Cra and cAMP Receptor Protein Have Opposing Roles in the Regulation of fruB in Vibrio cholerae

2021 ◽  
Vol 203 (10) ◽  
Author(s):  
Christina Beck ◽  
Sayde Perry ◽  
Daniel M. Stoebel ◽  
Jane M. Liu
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Mechanisms ◽  
Carbon Sources ◽  
Receptor Protein ◽  
Camp Receptor Protein ◽  
Phosphotransferase System ◽  
Content Type ◽  
Catabolite Repressor ◽  
Available Carbon ◽  
Camp Receptor

ABSTRACT The Gram-negative bacterium Vibrio cholerae adapts to changes in the environment by selectively producing the necessary machinery to take up and metabolize available carbohydrates. The import of fructose by the fructose-specific phosphoenolpyruvate (PEP) phosphotransferase system (PTS) is of particular interest because of its putative connection to cholera pathogenesis and persistence. Here, we describe the expression and regulation of fruB, which encodes an EIIA-FPr fusion protein as part of the fructose-specific PTS in V. cholerae. Using a series of transcriptional reporter fusions and additional biochemical and genetic assays, we identified Cra (catabolite repressor/activator) and cAMP receptor protein (CRP) as regulators of fruB expression and determined that this regulation is dependent upon the presence or absence of PTS sugars. Cra functions as a repressor, downregulating fruB expression in the absence of fructose when components of PTSFru are not needed. CRP functions as an activator of fruB expression. We also report that Cra and CRP can affect fruB expression independently; however, CRP can modulate cra expression in the presence of fructose and glucose. Evidence from this work provides the foundation for continued investigations into PTSFru and its relationship to the V. cholerae life cycle. IMPORTANCE Vibrio cholerae is the causative agent of cholera disease. While current treatments of care are accessible, we still lack an understanding of the molecular mechanisms that allow V. cholerae to survive in both aquatic reservoirs and the human small intestine, where pathogenesis occurs. Central to V. cholerae’s survival is its ability to use available carbon sources. Here, we investigate the regulation of fruB, which encodes a protein central to the import and metabolism of fructose. We show that fruB expression is controlled by the transcriptional regulators Cra and CRP. This work contributes toward a clearer understanding of how carbon source availability impacts the physiology and, potentially, the persistence of the pathogen.

scholarly journals The Phosphoenolpyruvate Phosphotransferase System Regulates Vibrio cholerae Biofilm Formation through Multiple Independent Pathways

2010 ◽  
Vol 192 (12) ◽  
pp. 3055-3067 ◽  
Author(s):  
Laetitia Houot ◽  
Sarah Chang ◽  
Bradley S. Pickering ◽  
Cedric Absalon ◽  
Paula I. Watnick
Keyword(s):  
Vibrio Cholerae ◽  
Biofilm Formation ◽  
Minimal Medium ◽  
Cellular Functions ◽  
Phosphotransferase System ◽  
Bacterial Genomes ◽  
Regulatory Pathways ◽  
Regulatory Circuits ◽  
Genes Encoding ◽  
Σ Factor

ABSTRACT The bacterial phosphoenolpyruvate phosphotransferase system (PTS) is a highly conserved phosphotransfer cascade that participates in the transport and phosphorylation of selected carbohydrates and modulates many cellular functions in response to carbohydrate availability. It plays a role in the virulence of many bacterial pathogens. Components of the carbohydrate-specific PTS include the general cytoplasmic components enzyme I (EI) and histidine protein (HPr), the sugar-specific cytoplasmic components enzymes IIA (EIIA) and IIB (EIIB), and the sugar-specific membrane-associated multisubunit components enzymes IIC (EIIC) and IID (EIID). Many bacterial genomes also encode a parallel PTS pathway that includes the EI homolog EINtr, the HPr homolog NPr, and the EIIA homolog EIIANtr. This pathway is thought to be nitrogen specific because of the proximity of the genes encoding this pathway to the genes encoding the nitrogen-specific σ factor σ54. We previously reported that phosphorylation of HPr and FPr by EI represses Vibrio cholerae biofilm formation in minimal medium supplemented with glucose or pyruvate. Here we report two additional PTS-based biofilm regulatory pathways that are active in LB broth but not in minimal medium. These pathways involve the glucose-specific enzyme EIIA (EIIAGlc) and two nitrogen-specific EIIA homologs, EIIANtr1 and EIIANtr2. The presence of multiple, independent biofilm regulatory circuits in the PTS supports the hypothesis that the PTS and PTS-dependent substrates have a central role in sensing environments suitable for a surface-associated existence.

scholarly journals Comparative Proteomics of Marinobacter sp. TT1 Reveals Corexit Impacts on Hydrocarbon Metabolism, Chemotactic Motility, and Biofilm Formation

2020 ◽  
Vol 9 (1) ◽  
pp. 3
Author(s):  
Saskia Rughöft ◽  
Nico Jehmlich ◽  
Tony Gutierrez ◽  
Sara Kleindienst
Keyword(s):  
Biofilm Formation ◽  
Oil Spills ◽  
Carbon Sources ◽  
Comparative Proteomics ◽  
Hydrocarbon Biodegradation ◽  
Solvent Tolerance ◽  
Marine Microorganisms ◽  
Degrading Bacteria ◽  
Oil Spill Response ◽  
First Time

The application of chemical dispersants during marine oil spills can affect the community composition and activity of marine microorganisms. Several studies have indicated that certain marine hydrocarbon-degrading bacteria, such as Marinobacter spp., can be inhibited by chemical dispersants, resulting in lower abundances and/or reduced biodegradation rates. However, a major knowledge gap exists regarding the mechanisms underlying these physiological effects. Here, we performed comparative proteomics of the Deepwater Horizon isolate Marinobacter sp. TT1 grown under different conditions. Strain TT1 received different carbon sources (pyruvate vs. n-hexadecane) with and without added dispersant (Corexit EC9500A). Additional treatments contained crude oil in the form of a water-accommodated fraction (WAF) or chemically-enhanced WAF (CEWAF; with Corexit). For the first time, we identified the proteins associated with alkane metabolism and alginate biosynthesis in strain TT1, report on its potential for aromatic hydrocarbon biodegradation and present a protein-based proposed metabolism of Corexit components as carbon substrates. Our findings revealed that Corexit exposure affects hydrocarbon metabolism, chemotactic motility, biofilm formation, and induces solvent tolerance mechanisms, like efflux pumps, in strain TT1. This study provides novel insights into dispersant impacts on microbial hydrocarbon degraders that should be taken into consideration for future oil spill response actions.

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