Pyruvate-triggered TCA cycle regulation in Staphylococcus aureus promotes tolerance to betamethasone valerate

Elaphoglossum luridum(Fée) Christ. (Dryopteridaceae) is an epiphytic fern of the Atlantic Forest (Brazil). Anatomical and physiological studies were conducted to understand how this plant responds to water stress. TheE. luridumfrond is coriaceus and succulent, presenting trichomes, relatively thick cuticle, and sinuous cell walls in both abaxial and adaxial epidermis. Three treatments were analyzed: control, water deficit, and abscisic acid (ABA). Physiological studies were conducted through analysis of relative water content (RWC), photosynthetic pigments, chlorophyll a fluorescence, and malate content. No changes in RWC were observed among treatments; however, significant decreases in chlorophyll a content and photosynthetic parameters, including optimal irradiance (Iopt) and maximum electron transport rate (ETRmax), were determined by rapid light curves (RLC). No evidence of crassulacean acid metabolism (CAM) pathway was observed inE. luridumin response to either water deficit or exogenous application of ABA. On the other hand, malate content decreased in theE. luridumfrond after ABA treatment, seeming to downregulate malate metabolism at night, possibly through tricarboxylic acid (TCA) cycle regulation.

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Genetic Evidence for an Alternative Citrate-Dependent Biofilm Formation Pathway in Staphylococcus aureus That Is Dependent on Fibronectin Binding Proteins and the GraRS Two-Component Regulatory System

Infection and Immunity ◽

10.1128/iai.01370-07 ◽

2008 ◽

Vol 76 (6) ◽

pp. 2469-2477 ◽

Cited By ~ 44

Author(s):

Robert M. Q. Shanks ◽

Michael A. Meehl ◽

Kimberly M. Brothers ◽

Raquel M. Martinez ◽

Niles P. Donegan ◽

...

Keyword(s):

Gene Expression ◽

Staphylococcus Aureus ◽

Biofilm Formation ◽

Binding Proteins ◽

Regulatory System ◽

Tca Cycle ◽

Formation Pathway ◽

Two Component ◽

Fibronectin Binding ◽

Tca Cycle Intermediates

ABSTRACT We reported previously that low concentrations of sodium citrate strongly promote biofilm formation by Staphylococcus aureus laboratory strains and clinical isolates. Here, we show that citrate promotes biofilm formation via stimulating both cell-to-surface and cell-to-cell interactions. Citrate-stimulated biofilm formation is independent of the ica locus, and in fact, citrate represses polysaccharide adhesin production. We show that fibronectin binding proteins FnbA and FnbB and the global regulator SarA, which positively regulates fnbA and fnbB gene expression, are required for citrate's positive effects on biofilm formation, and citrate also stimulates fnbA and fnbB gene expression. Biofilm formation is also stimulated by several other tricarboxylic acid (TCA) cycle intermediates in an FnbA-dependent fashion. While aconitase contributes to biofilm formation in the absence of TCA cycle intermediates, it is not required for biofilm stimulation by these compounds. Furthermore, the GraRS two-component regulator and the GraRS-regulated efflux pump VraFG, identified for their roles in intermediate vancomycin resistance, are required for citrate-stimulated cell-to-cell interactions, but the GraRS regulatory system does not impact the expression of the fnbA and fnbB genes. Our data suggest that distinct genetic factors are required for the early steps in citrate-stimulated biofilm formation. Given the role of FnbA/FnbB and SarA in virulence in vivo and the lack of a role for ica-mediated biofilm formation in S. aureus catheter models of infection, we propose that the citrate-stimulated biofilm formation pathway may represent a clinically relevant pathway for the formation of these bacterial communities on medical implants.

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A Case of Pyruvate Carboxylase Deficiency With Longer Survival and Normal Laboratory Findings

ACTA MEDICA IRANICA ◽

10.18502/acta.v59i10.7772 ◽

2021 ◽

Author(s):

Reza Bayat ◽

Shahin Koohmanaee ◽

Nejat Mahdieh ◽

Fatemeh Kharaee ◽

Maryam Shahrokhi ◽

...

Keyword(s):

Pyruvate Carboxylase ◽

Amino Acid Level ◽

Tca Cycle ◽

Type B ◽

Laboratory Findings ◽

Short Life Span ◽

Pyruvate Carboxylase Deficiency ◽

Almost All ◽

Cycle Regulation ◽

Recessive Defect

Pyruvate carboxylase deficiency (PCD) is a rare autosomal recessive defect in a biotin-containing enzyme, Pyruvate carboxylase, which is considered as an enzyme of TCA-cycle regulation, gluconeogenesis, lipogenesis, and biosynthesis of neurotransmitters. Increased lactate to pyruvate ratio and decreased three hydroxybutyrates to acetoacetate are the main biochemical features of PCD. The elevated level of Citrulline, Proline, and Lysine with a short life span has been reported previously. Patients’ survival in almost all cases is below three months. Here, the authors aimed to report a girl with manifestations of Type B of PCD and longer survival (two-year and four-month-old). This patient did not have any changes in amino acid level, which was a unique case of Type B of PCD.

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Interruption of the tricarboxylic acid cycle in Staphylococcus aureus leads to increased tolerance to innate immunity

AIMS Microbiology ◽

10.3934/microbiol.2021031 ◽

2021 ◽

Vol 7 (4) ◽

pp. 513-527

Author(s):

Alexis M. Hobbs ◽

◽

Kennedy E. Kluthe ◽

Kimberly A. Carlson ◽

Austin S. Nuxoll

Keyword(s):

Staphylococcus Aureus ◽

Immune System ◽

Innate Immune System ◽

Tricarboxylic Acid Cycle ◽

Fold Increase ◽

Tca Cycle ◽

Tricarboxylic Acid ◽

Innate Immune ◽

Antibiotic Tolerance ◽

Males And Females

<abstract> <p><italic>Staphylococcus aureus</italic> is widely known for its resistance and virulence causing public health concerns. However, antibiotic tolerance is also a contributor to chronic and relapsing infections. Previously, it has been demonstrated that persister formation is dependent on reduced tricarboxylic acid (TCA) cycle activity. Persisters have been extensively examined in terms of antibiotic tolerance but tolerance to antimicrobial peptides (AMPs) remains largely unexplored. AMPs are a key component of both the human and <italic>Drosophila</italic> innate immune response. TCA cycle mutants were tested to determine both antibiotic and AMP tolerance. Challenging with multiple classes of antibiotics led to increased persister formation (100- to 1,000-fold). Similarly, TCA mutants exhibited AMP tolerance with a 100- to 1,000-fold increase in persister formation when challenged with LL-37 or human β-defensin 3 (hβD3). The ability of TCA cycle mutants to tolerate the innate immune system was further examined with a <italic>D. melanogaster</italic> model. Both males and females infected with TCA cycle mutants exhibited increased mortality and had higher bacterial burdens (1.5 log) during the course of the infection. These results suggest increasing the percentage of persister cells leads to increased tolerance to components of the innate immune system.</p> </abstract>

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Structural and ligand binding analyses of the periplasmic sensor domain of RsbU in Chlamydia trachomatis support a role in TCA cycle regulation

Molecular Microbiology ◽

10.1111/mmi.14401 ◽

2019 ◽

Vol 113 (1) ◽

pp. 68-88 ◽

Cited By ~ 1

Author(s):

Katelyn R. Soules ◽

Aidan Dmitriev ◽

Scott D. LaBrie ◽

Zoë E. Dimond ◽

Benjamin H. May ◽

...

Keyword(s):

Chlamydia Trachomatis ◽

Ligand Binding ◽

Tca Cycle ◽

Cycle Regulation

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Staphylococcus aureus ClpC Is Required for Stress Resistance, Aconitase Activity, Growth Recovery, and Death

Journal of Bacteriology ◽

10.1128/jb.187.13.4488-4496.2005 ◽

2005 ◽

Vol 187 (13) ◽

pp. 4488-4496 ◽

Cited By ~ 71

Author(s):

Indranil Chatterjee ◽

Petra Becker ◽

Matthias Grundmeier ◽

Markus Bischoff ◽

Greg A. Somerville ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Stationary Phase ◽

Critical Role ◽

Tca Cycle ◽

Term Survival ◽

Phase Recovery ◽

Growth And Survival ◽

Aconitase Activity

ABSTRACT The ability of Staphylococcus aureus to adapt to various conditions of stress is the result of a complex regulatory response. Previously, it has been demonstrated that Clp homologues are important for a variety of stress conditions, and our laboratory has shown that a clpC homologue was highly expressed in the S. aureus strain DSM20231 during biofilm formation relative to expression in planktonic cells. Persistence and long-term survival are a hallmark of biofilm-associated staphylococcal infections, as cure frequently fails even in the presence of bactericidal antimicrobials. To determine the role of clpC in this context, we performed metabolic, gene expression, and long-term growth and survival analyses of DSM20231 as well as an isogenic clpC allelic-replacement mutant, a sigB mutant, and a clpC sigB double mutant. As expected, the clpC mutant showed increased sensitivity to oxidative and heat stresses. Unanticipated, however, was the reduced expression of the tricarboxylic acid (TCA) cycle gene citB (encoding aconitase), resulting in the loss of aconitase activity and preventing the catabolization of acetate during the stationary phase. clpC inactivation abolished post-stationary-phase recovery but also resulted in significantly enhanced stationary-phase survival compared to that of the wild-type strain. These data demonstrate the critical role of the ClpC ATPase in regulating the TCA cycle and implicate ClpC as being important for recovery from the stationary phase and also for entering the death phase. Understanding the stationary- and post-stationary-phase recovery in S. aureus may have important clinical implications, as little is known about the mechanisms of long-term persistence of chronic S. aureus infections associated with formation of biofilms.

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TCA cycle inactivation in Staphylococcus aureus alters nitric oxide production in RAW 264.7 cells

Molecular and Cellular Biochemistry ◽

10.1007/s11010-011-0840-3 ◽

2011 ◽

Vol 355 (1-2) ◽

pp. 75-82 ◽

Cited By ~ 8

Author(s):

Chandirasegaran Massilamany ◽

Arunakumar Gangaplara ◽

Donald J. Gardner ◽

James M. Musser ◽

David Steffen ◽

...

Keyword(s):

Nitric Oxide ◽

Staphylococcus Aureus ◽

Tca Cycle ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Nitric Oxide Production ◽

Oxide Production

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Advantage of Upregulation of Succinate Dehydrogenase in Staphylococcus aureus Biofilms

Journal of Bacteriology ◽

10.1128/jb.01472-09 ◽

2010 ◽

Vol 192 (9) ◽

pp. 2385-2394 ◽

Cited By ~ 55

Author(s):

Rosmarie Gaupp ◽

Steffen Schlag ◽

Manuel Liebeke ◽

Michael Lalk ◽

Friedrich Götz

Keyword(s):

Staphylococcus Aureus ◽

Acetic Acid ◽

Succinate Dehydrogenase ◽

Growth Medium ◽

Tca Cycle ◽

Defined Medium ◽

Metabolome Analysis ◽

Aerobic Conditions ◽

Small Colony Variant ◽

The Tca Cycle

ABSTRACT Previous studies have demonstrated that various tricarboxylic acid (TCA) cycle genes, particularly the succinate dehydrogenase genes (sdhCAB), are upregulated in Staphylococcus aureus biofilms. To better study the role of this enzyme complex, an sdhCAB deletion mutant (Δsdh) was constructed. Compared to the wild type (wt) the mutant was impaired in planktonic growth under aerobic conditions, excreted acetic acid could not be reused and accumulated continuously, succinate was excreted and found in the culture supernatant, and metabolome analysis with cells grown in chemically defined medium revealed reduced uptake/metabolism of some amino acids from the growth medium. Moreover, the mutant was able to counteract the steadily decreasing extracellular pH by increased urease activity. The addition of fumarate to the growth medium restored the wt phenotype. The mutant showed a small-colony variant (SCV)-like phenotype, a slight increase in resistance to various aminoglycoside antibiotics, and decreased pigmentation. The decreased growth under aerobic conditions is due to the interruption of the TCA cycle (indicated by the accumulation of succinate and acetic acid) with the consequence that many fewer reduction equivalents (NADH and FADH2) can fuel the respiratory chain. The results indicate that the TCA cycle is required for acetate and amino acid catabolism; its upregulation under biofilm conditions is advantageous under such nutrient- and oxygen-limited conditions.

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The msaABCR Operon Regulates Persister Formation by Modulating Energy Metabolism in Staphylococcus aureus

Frontiers in Microbiology ◽

10.3389/fmicb.2021.657753 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shanti Pandey ◽

Gyan S. Sahukhal ◽

Mohamed O. Elasri

Keyword(s):

Staphylococcus Aureus ◽

Energy Metabolism ◽

Tca Cycle ◽

Antibiotic Tolerance ◽

Atp Content ◽

Persister Cells ◽

Metabolic Genes ◽

Starting Point ◽

Metabolic Activities ◽

Systemic Infections

Staphylococcus aureus is a major human pathogen that causes chronic, systemic infections, and the recalcitrance of these infections is mainly due to the presence of persister cells, which are a bacterial subpopulation that exhibits extreme, yet transient, antibiotic tolerance accompanied by a transient halt in growth. However, upon cessation of antibiotic treatment, a resumption in growth of persister cells causes recurrence of infections and treatment failure. Previously, we reported the involvement of msaABCR in several important staphylococcal phenotypes, including the formation of persister cells. Additionally, observations of the regulation of several metabolic genes by the msaABCR operon in transcriptomics and proteomics analyses have suggested its role in the metabolic activities of S. aureus. Given the importance of metabolism in persister formation as our starting point, in this study we demonstrated how the msaABCR operon regulates energy metabolism and subsequent antibiotic tolerance. We showed that deletion of the msaABCR operon results in increased tricarboxylic acid (TCA) cycle activity, accompanied by increased cellular ATP content and higher NADH content in S. aureus cells. We also showed that msaABCR (through MsaB) represses the ccpE and ndh2 genes, thereby regulating TCA cycle activity and the generation of membrane potential, respectively. Together, the observations from this study led to the conclusion that msaABCR operon deletion induces a metabolically hyperactive state, leading to decreased persister formation in S. aureus.

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