c-di-AMP signaling is required for bile salts resistance and long-term colonization by Clostridioides difficile

ABSTRACTTo cause disease, the important human enteropathogen Clostridioides difficile must colonize the gastro-intestinal tract but little is known on how this organism senses and responds to the harsh host environment to adapt and multiply. Nucleotide second messengers are signaling molecules used by bacteria to respond to changing environmental conditions. In this study, we showed for the first time that c-di-AMP is produced by C. difficile and controls the uptake of potassium, making it essential for growth. We found that c-di-AMP is involved in biofilm formation, cell wall homeostasis, osmotolerance as well as detergent and bile salt resistance in C. difficile. In a colonization mouse model, a strain lacking GdpP, a c-di-AMP degrading enzyme, failed to persist in the gut in contrast to the parental strain. We identified OpuR as a new regulator that binds c-di-AMP and represses the expression of the compatible solute transporter OpuC. Interestingly, an opuR mutant is highly resistant to a hyperosmotic or bile salt stress compared to the parental strain while an opuCA mutant is more susceptible A short exposure of C. difficile cells to bile salts resulted in a decrease of the c-di-AMP concentrations reinforcing the hypothesis that changes in membrane characteristics due to variations of the cellular turgor or membrane damages constitute a signal for the adjustment of the intracellular c-di-AMP concentration. Thus, c-di-AMP is a signaling molecule with pleiotropic effects that controls osmolyte uptake to confer osmotolerance and bile salt resistance in C. difficile and that is important for colonization of the host.One Sentence Summaryc-di-AMP is an essential regulatory molecule conferring resistance to osmotic and bile salt stresses by controlling osmolyte uptake and contributing to gut persistence in the human enteropathogen Clostridioides difficile.

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STUDI VIABILITAS ISOLAT BAKTERI ASAM LAKTAT YANG DIISOLASI DARI ASINAN REBUNG BAMBU TABAH TERHADAP pH RENDAH DAN GARAM EMPEDU

JURNAL REKAYASA DAN MANAJEMEN AGROINDUSTRI ◽

10.24843/jrma.2019.v07.i01.p01 ◽

2019 ◽

Vol 7 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Nurul Octavia Wasis ◽

Nyoman Semadi Antara ◽

Ida Bagus Wayan Gunam

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bile Salt ◽

Bile Salts ◽

Salt Resistance ◽

Low Ph ◽

Fermented Food ◽

Bamboo Shoot ◽

Probiotic Lactic Acid Bacteria ◽

Mrs Broth

Tabah bamboo shoot pickle is one of the fermented food which is the source of lactic acid bacteria. Lactic acid bacteria (LAB) is beneficial to health because it has the ability as a probiotic. Lactic acid bacteria that have probiotic criteria should have resistance to low pH and bile salts. This study aims to determine isolates of lactic acid bacteria isolated from tabah bamboo shoot pickle resistant to low pH and bile salts (NaDC). Lactic acid bacteria were tested to low pH by using MRS broth that have different pH (pH 2, pH 3, pH 4 and pH 6.2 as a control) incubated at 37ºC for 3 hours. isolates were survive in low pH then continued in bile salt resistance test with 0.3% bile salt concentration for 15 minutes, 30 minutes, 45 minutes, 60 minutes and 24 hours. The results showed that three isolates out of 88 isolates had ability to grow in low pH and in medium supplemented by NaDC 0,3%. The isolates are AR 3057, AR 3101 and AR 6152 which can be used as candidat of probiotic. Keywords : Tabah bamboo shoot pickle, lactic acid bacteria, probiotic, low pH, bile salt

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Probiotic Candidates Yeast Isolated from Dangke – Indonesian Traditional Fermented Buffalo Milk

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201967010179 ◽

2019 ◽

Vol 67 (1) ◽

pp. 179-187

Author(s):

Gemilang Lara Utama ◽

Siska Meliana ◽

Mohamad Djali ◽

Tri Yuliana ◽

Roostita L. Balia

Keyword(s):

Bile Salt ◽

Bile Salts ◽

Pathogenic Bacteria ◽

Salt Resistance ◽

Buffalo Milk ◽

Candida Guilliermondii ◽

Resistance Test ◽

Smooth Surfaces ◽

Ability Test ◽

Probiotic Yeast

The aim of the study was to isolate and identify the yeast isolated from Dangke and its potential as probiotics. The purified isolates obtained were identified based on observations of macroscopic characteristics of colonies and microscopic cells. The ability as a probiotic yeast is obtained by testing the resistance towards acid conditions, bile salt resistance test and aggregation ability test against pathogenic bacteria using Salmonella sp. The yeast isolates were identified using the RapID Yeast Plus System. The isolation result was obtained D.10.3.d isolate that identified as Candida guilliermondii which showed probiotic characteristic. The yeast colony is round, cream‑colored, smooth surfaces, low convex elevations and entire edges, capable of growing on mediums with the pH of 4, containing 1 % and 5 % of bile salts and having the ability to aggregate Salmonella sp. at 15, 60, and 180 minutes.

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An Active Type IV Secretion System Encoded by the F Plasmid Sensitizes Escherichia coli to Bile Salts

Journal of Bacteriology ◽

10.1128/jb.186.16.5202-5209.2004 ◽

2004 ◽

Vol 186 (16) ◽

pp. 5202-5209 ◽

Cited By ~ 12

Author(s):

James E. Bidlack ◽

Philip M. Silverman

Keyword(s):

Escherichia Coli ◽

Bile Salt ◽

Bile Salts ◽

Cell Envelope ◽

Sodium Dodecyl ◽

Salt Resistance ◽

Salt Sensitivity ◽

Plating Efficiency ◽

Active System ◽

Type Iv

ABSTRACT F+ strains of Escherichia coli infected with donor-specific bacteriophage such as M13 are sensitive to bile salts. We show here that this sensitivity has two components. The first derives from secretion of bacteriophage particles through the cell envelope, but the second can be attributed to expression of the F genes required for the formation of conjugative (F) pili. The latter component was manifested as reduced or no growth of an F+ strain in liquid medium containing bile salts at concentrations that had little or no effect on the isogenic F− strain or as a reduced plating efficiency of the F+ strain on solid media; at 2% bile salts, plating efficiency was reduced 104-fold. Strains with F or F-like R factors were consistently more sensitive to bile salts than isogenic, plasmid-free strains, but the quantitative effect of bile salts depended on both the plasmid and the strain. Sensitivity also depended on the bile salt, with conjugated bile salts (glycocholate and taurocholate) being less active than unconjugated bile salts (deoxycholate and cholate). F+ cells were also more sensitive to sodium dodecyl sulfate than otherwise isogenic F− cells, suggesting a selectivity for amphipathic anions. A mutation in any but one F tra gene required for the assembly of F pili, including the traA gene encoding F pilin, substantially restored bile salt resistance, suggesting that bile salt sensitivity requires an active system for F pilin secretion. The exception was traW. A traW mutant was 100-fold more sensitive to cholate than the tra+ strain but only marginally more sensitive to taurocholate or glycocholate. Bile salt sensitivity could not be attributed to a generalized change in the surface permeability of F+ cells, as judged by the effects of hydrophilic and hydrophobic antibiotics and by leakage of periplasmic β-lactamase into the medium.

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Faculty Opinions recommendation of Atp8b1 deficiency in mice reduces resistance of the canalicular membrane to hydrophobic bile salts and impairs bile salt transport.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1032307.374677 ◽

2006 ◽

Author(s):

Bruno Stieger

Keyword(s):

Bile Salt ◽

Bile Salts ◽

Salt Transport ◽

Canalicular Membrane ◽

Bile Salt Transport

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The antimicrobial potential of cannabidiol

Communications Biology ◽

10.1038/s42003-020-01530-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Mark A. T. Blaskovich ◽

Angela M. Kavanagh ◽

Alysha G. Elliott ◽

Bing Zhang ◽

Soumya Ramu ◽

...

Keyword(s):

Bacterial Infections ◽

Modern Medicine ◽

Gram Negative Bacteria ◽

Gram Negative ◽

New Class ◽

Clostridioides Difficile ◽

Excellent Activity ◽

Induce Resistance ◽

First Time

AbstractAntimicrobial resistance threatens the viability of modern medicine, which is largely dependent on the successful prevention and treatment of bacterial infections. Unfortunately, there are few new therapeutics in the clinical pipeline, particularly for Gram-negative bacteria. We now present a detailed evaluation of the antimicrobial activity of cannabidiol, the main non-psychoactive component of cannabis. We confirm previous reports of Gram-positive activity and expand the breadth of pathogens tested, including highly resistant Staphylococcus aureus, Streptococcus pneumoniae, and Clostridioides difficile. Our results demonstrate that cannabidiol has excellent activity against biofilms, little propensity to induce resistance, and topical in vivo efficacy. Multiple mode-of-action studies point to membrane disruption as cannabidiol’s primary mechanism. More importantly, we now report for the first time that cannabidiol can selectively kill a subset of Gram-negative bacteria that includes the ‘urgent threat’ pathogen Neisseria gonorrhoeae. Structure-activity relationship studies demonstrate the potential to advance cannabidiol analogs as a much-needed new class of antibiotics.

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Rapid kinetics of second messenger production in bitter taste

AJP Cell Physiology ◽

10.1152/ajpcell.1996.270.3.c926 ◽

1996 ◽

Vol 270 (3) ◽

pp. C926-C931 ◽

Cited By ~ 56

Author(s):

A. I. Spielman ◽

H. Nagai ◽

G. Sunavala ◽

M. Dasso ◽

H. Breer ◽

...

Keyword(s):

Bitter Taste ◽

Second Messengers ◽

Second Messenger ◽

Mouse Strains ◽

Protective Mechanism ◽

Transient Nature ◽

Sucrose Octaacetate ◽

Rapid Kinetics ◽

First Time

The tasting of bitter compounds may have evolved as a protective mechanism against ingestion of potentially harmful substances. We have identified second messengers involved in bitter taste and show here for the first time that they are rapid and transient. Using a quench-flow system, we have studied bitter taste signal transduction in a pair of mouse strains that differ in their ability to taste the bitter stimulus sucrose octaacetate (SOA); however, both strains taste the bitter agent denatonium. In both strains of mice, denatonium (10 mM) induced a transient and rapid increase in levels of the second messenger inositol 1,4,5-trisphosphate (IP3) with a maximal production near 75-100 ms after stimulation. In contrast, SOA (100 microM) brought about a similar increase in IP3 only in SOA-taster mice. The response to SOA was potentiated in the presence of GTP (1 microM). The GTP-enhanced SOA-response supports a G protein-mediated response for this bitter compound. The rapid kinetics, transient nature, and specificity of the bitter taste stimulus-induced IP3 formation are consistent with the role of IP3 as a second messenger in the chemoelectrical transduction of bitter taste.

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Regulation of mdr2 P-glycoprotein expression by bile salts

Biochemical Journal ◽

10.1042/bj3210389 ◽

1997 ◽

Vol 321 (2) ◽

pp. 389-395 ◽

Cited By ~ 39

Author(s):

Charles M. G. FRIJTERS ◽

Roelof OTTENHOFF ◽

Michel J. A. van WIJLAND ◽

Carin M. J. van NIEUWKERK ◽

Albert K. GROEN ◽

...

Keyword(s):

Bile Salt ◽

Bile Salts ◽

Control Diet ◽

Mrna Level ◽

Northern Blotting ◽

Mrna Levels ◽

Male Mice ◽

Complete Replacement ◽

P Glycoprotein ◽

Mrna Content

The phosphatidyl translocating activity of the mdr2 P-glycoprotein (Pgp) in the canalicular membrane of the mouse hepatocyte is a rate-controlling step in the biliary secretion of phospholipid. Since bile salts also regulate the secretion of biliary lipids, we investigated the influence of the type of bile salt in the circulation on mdr2 Pgp expression and activity. Male mice were fed a purified diet to which either 0.1% (w/w) cholate or 0.5% (w/w) ursodeoxycholate was added. This led to a near-complete replacement of the endogenous bile salt pool (mainly tauromuricholate) by taurocholate or tauroursodeoxycholate respectively. The phospholipid secretion capacity was then determined by infusion of increasing amounts of tauroursodeoxycholate. Cholate feeding resulted in a 55% increase in maximal phospholipid secretion compared with that in mice on the control diet. Northern blotting revealed that cholate feeding increased mdr2 Pgp mRNA levels by 42%. Feeding with ursodeoxycholate did not influence the maximum rate of phospholipid output or the mdr2 mRNA content. Female mice had a higher basal mdr2 Pgp mRNA level than male mice, and this was also correlated with a higher phospholipid secretion capacity. This could be explained by the 4-fold higher basal cholate content in the bile of female compared with male mice. Our results suggest that the type of bile salts in the circulation influences the expression of the mdr2 gene.

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Characteristics of bile salt uptake into skate hepatocytes

Biochemical Journal ◽

10.1042/bj2990665 ◽

1994 ◽

Vol 299 (3) ◽

pp. 665-670 ◽

Cited By ~ 14

Author(s):

G Fricker ◽

V Dubost ◽

K Finsterwald ◽

J L Boyer

Keyword(s):

Substrate Specificity ◽

Bile Salt ◽

Transport System ◽

Bile Salts ◽

Organic Anion ◽

Anion Transport ◽

Organic Anion Transport ◽

Salt Uptake ◽

Anion Transport System ◽

Alpha 7

The substrate specificity for the transporter that mediates the hepatic uptake of organic anions in freshly isolated hepatocytes of the elasmobranch little skate (Raja erinacea) was determined for bile salts and bile alcohols. The Na(+)-independent transport system exhibits a substrate specificity, which is different from the specificity of Na(+)-dependent bile salt transport in mammals. Unconjugated and conjugated di- and tri-hydroxylated bile salts inhibit uptake of cholyltaurine and cholate competitively. Inhibition is significantly greater with unconjugated as opposed to glycine- or taurine-conjugated bile salts. However, the number of hydroxyl groups in the steroid moiety of the bile salts has only minor influences on the inhibition by the unconjugated bile salts. Since the transport system seems to represent an archaic organic-anion transport system, other anions, such as dicarboxylates, amino acids and sulphate, were also tested, but had no inhibitory effect on bile salt uptake. To clarify whether bile alcohols, the physiological solutes in skate bile, share this transport system, cholyltaurine transport was studied after addition of 5 beta-cholestane-3 beta,5 alpha,6 beta-triol, 5 alpha-cholestan-3 beta-ol and 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol. These bile alcohols inhibit cholyltaurine uptake non-competitively. In contrast, uptake of 5 beta-cholestane-3 alpha,7 alpha,12 alpha-triol, which is Na(+)-independent, is not inhibited by cholyltaurine. The findings further characterize a Na(+)-independent organic-anion transport system in skate liver cells, which is not shared by bile alcohols and has preference for unconjugated lipophilic bile salts.

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An aniline-substituted bile salt analog protects both mice and hamsters from multiple Clostridioides difficile strains

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01435-21 ◽

2021 ◽

Author(s):

Jacqueline R. Phan ◽

Dung M. Do ◽

Minh Chau Truong ◽

Connie Ngo ◽

Julian H. Phan ◽

...

Keyword(s):

Bile Salt ◽

Spore Germination ◽

Dependent Manner ◽

Germination Inhibitors ◽

New Methods ◽

Clostridioides Difficile ◽

Antibiotic Associated Diarrhea ◽

Careful Screening ◽

Strain Dependent

Clostridioides difficile infection (CDI) is the major identifiable cause of antibiotic-associated diarrhea. The emergence of hypervirulent C. difficile strains has led to increases in both hospital- and community-acquired CDI. Furthermore, CDI relapse from hypervirulent strains can reach up to 25%. Thus, standard treatments are rendered less effective, making new methods of prevention and treatment more critical. Previously, the bile salt analog CamSA was shown to inhibit spore germination in vitro and protect mice and hamsters from C. difficile strain 630. Here, we show that CamSA was less active at preventing spore germination of other C. difficile ribotypes, including the hypervirulent strain R20291. Strain-specific in vitro germination activity of CamSA correlated with its ability to prevent CDI in mice. Additional bile salt analogs were screened for in vitro germination inhibition activity against strain R20291, and the most active compounds were tested against other strains. An aniline-substituted bile salt analog, (CaPA), was found to be a better anti-germinant than CamSA against eight different C. difficile strains. In addition, CaPA was capable of reducing, delaying, or preventing murine CDI signs in all strains tested. CaPA-treated mice showed no obvious toxicity and showed minor effects on their gut microbiome. CaPA’s efficacy was further confirmed by its ability to prevent CDI in hamsters infected with strain 630. These data suggest that C. difficile spores respond to germination inhibitors in a strain-dependent manner. However, careful screening can identify anti-germinants with broad CDI prophylaxis activity.

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