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Cell Reports May 2024Quorum sensing (QS) is a cell-to-cell communication mechanism mediated by small diffusible signaling molecules. Previous studies showed that RpfR controls Burkholderia...
Quorum sensing (QS) is a cell-to-cell communication mechanism mediated by small diffusible signaling molecules. Previous studies showed that RpfR controls Burkholderia cenocepacia virulence as a cis-2-dodecenoic acid (BDSF) QS signal receptor. Here, we report that the fatty acyl-CoA ligase DsfR (BCAM2136), which efficiently catalyzes in vitro synthesis of lauryl-CoA and oleoyl-CoA from lauric acid and oleic acid, respectively, acts as a global transcriptional regulator to control B. cenocepacia virulence by sensing BDSF. We show that BDSF binds to DsfR with high affinity and enhances the binding of DsfR to the promoter DNA regions of target genes. Furthermore, we demonstrate that the homolog of DsfR in B. lata, RS02960, binds to the target gene promoter, and perception of BDSF enhances the binding activity of RS02960. Together, these results provide insights into the evolved unusual functions of DsfR that control bacterial virulence as a response regulator of QS signal.
Topics: Quorum Sensing; Burkholderia cenocepacia; Virulence; Bacterial Proteins; Coenzyme A Ligases; Gene Expression Regulation, Bacterial; Promoter Regions, Genetic; Animals; Signal Transduction; Fatty Acids, Monounsaturated; Mice; Protein Binding; Lauric Acids
PubMed: 38748879
DOI: 10.1016/j.celrep.2024.114223 -
The Journal of Infectious Diseases Mar 2024Bone infections from Staphylococcus aureus are notoriously difficult to treat and have high recurrence rates. Local antibiotic delivery systems hold the potential to...
BACKGROUND
Bone infections from Staphylococcus aureus are notoriously difficult to treat and have high recurrence rates. Local antibiotic delivery systems hold the potential to achieve high in situ antibiotic concentrations, which are otherwise challenging to achieve via systemic administration. Existing solutions have been shown to confer suboptimal drug release and distribution. Here we present and evaluate an injectable in situ-forming depot system termed CarboCell. The CarboCell technology provides sustained and tuneable release of local high-dose antibiotics.
METHODS
CarboCell formulations of levofloxacin or clindamycin with or without antimicrobial adjuvants cis-2-decenoic acid or cis-11-methyl-2-dodecenoic acid were tested in experimental rodent and porcine implant-associated osteomyelitis models. In the porcine models, debridement and treatment with CarboCell-formulated antibiotics was carried out without systemic antibiotic administration. The bacterial burden was determined by quantitative bacteriology.
RESULTS
CarboCell formulations eliminated S. aureus in infected implant rat models. In the translational implant-associated pig model, surgical debridement, and injection of clindamycin-releasing CarboCell formulations resulted in pathogen-free bone tissues and implants in 9/12, and full eradication in 5/12 pigs.
CONCLUSIONS
Sustained release of antimicrobial agents mediated by the CarboCell technology demonstrated promising therapeutic efficacy in challenging translational models and may be beneficial in combination with the current standard of care.
PubMed: 38537273
DOI: 10.1093/infdis/jiae139 -
Reproductive Toxicology (Elmsford, N.Y.) Apr 2024Apilarnil, a bee-derived product originating from drone larvae, offers a range of advantageous properties for both humans and animals. It functions as an antioxidant,...
Apilarnil, a bee-derived product originating from drone larvae, offers a range of advantageous properties for both humans and animals. It functions as an antioxidant, provides neuroprotection, boosts fertility, and has antiviral capabilities. Additionally, it is a provider of androgenic hormones. These beneficial functions are supported by its chemical composition, which comprises mineral salts, vitamins, carbs, lipids, hormones, and amino acids. The current study aimed to evaluate the ameliorative effect of apilarnil against Bisphenol A (BPA)-induced testicular toxicity in male adult rats. Forty-eight Wistar albino rats were randomly classified into six groups. The first, second, and third received olive oil, BPA at a dose of 50 mg/kg body weight (bwt), and apilarnil at a dose of 0.6 g/kg bwt, respectively. The fourth, fifth, and sixth groups received apilarnil with, before, or after BPA administration, respectively. Phytochemical analysis using included linear ion trap-ultra-performance liquid chromatography-tandem mass spectrometry (LTQ-UPLC-MS/MS) and global natural products social molecular networking (GNPS) revealed the presence of lysine, 10-hydroxy-(E)-2-dodecenoic acid, apigenin7-glucoside, testosterone, progesterone, and campesterol. BPA administration decreased serum level of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, glutathione (GSH) concentration, total sperm count, motility, and vitality. Additionally, BPA increased sperm abnormalities, malondialdehyde concentration (MDA), and decreased proliferating cell nuclear antigen (PCNA) expression. The treatment with apilarnil ameliorated BPA reproductive toxicity in rats which was indicated by increased serum testosterone levels, normalized serum levels of FSH and LH, and concentration of MDA and GSH activity. Moreover, apilarnil improved sperm count, motility, morphology, and PCNA expression. Apilarnil was found to enhance reproductive hormones, MDA levels, antioxidant activity, and PCNA expression.
Topics: Adult; Animals; Humans; Male; Rats; Antioxidants; Benzhydryl Compounds; Biological Products; Chromatography, Liquid; Follicle Stimulating Hormone; Glutathione; Luteinizing Hormone; Oxidative Stress; Phenols; Proliferating Cell Nuclear Antigen; Rats, Wistar; Sperm Count; Tandem Mass Spectrometry; Testis; Testosterone
PubMed: 38484946
DOI: 10.1016/j.reprotox.2024.108570 -
Molecular Plant-microbe Interactions :... Jan 2024Numerous bacterial species employ diffusible signal factor (DSF)-based quorum sensing (QS) as a widely conserved cell-cell signaling communication system to collectively... (Review)
Review
Numerous bacterial species employ diffusible signal factor (DSF)-based quorum sensing (QS) as a widely conserved cell-cell signaling communication system to collectively regulate various behaviors crucial for responding to environmental changes. -11-Methyl-dodecenoic acid, known as DSF, was first identified as a signaling molecule in pv. . Subsequently, many structurally related molecules have been identified in different bacterial species. This review aims to provide an overview of current understanding regarding the biosynthesis and regulatory role of DSF signals in both pathogenic bacteria and a biocontrol bacterium. Recent studies have revealed that the DSF-based QS system regulates antimicrobial factor production in a cyclic dimeric GMP-independent manner in the biocontrol bacterium . Additionally, the DSF family signals have been found to be involved in suppressing plant innate immunity. The discovery of these diverse signaling mechanisms holds significant promise for developing novel strategies to combat stubborn plant pathogens. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Topics: Quorum Sensing; Xanthomonas campestris; Signal Transduction; Cyclic GMP; Bacterial Proteins
PubMed: 37880815
DOI: 10.1094/MPMI-05-23-0074-CR -
Applied and Environmental Microbiology Oct 2023Outer membrane vesicle (OMV)-delivered quinolone signal (PQS) plays a critical role in cell-cell communication in . However, the functions and mechanisms of...
Outer membrane vesicle (OMV)-delivered quinolone signal (PQS) plays a critical role in cell-cell communication in . However, the functions and mechanisms of membrane-enclosed PQS in interspecies communication in microbial communities are not clear. Here, we demonstrate that PQS delivered by both OMVs from and liposome reduces the competitiveness of , which usually shares the same niche in the lungs of cystic fibrosis patients, by interfering with quorum sensing (QS) in through the LysR-type regulator ShvR. Intriguingly, we found that ShvR regulates the production of the QS signals cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) by directly binding to the promoters of signal synthase-encoding genes. Perception of PQS influences the regulatory activity of ShvR and thus ultimately reduces QS signal production and virulence in . Our findings provide insights into the interspecies communication mediated by the membrane-enclosed QS signal among bacterial species residing in the same microbial community.IMPORTANCEQuorum sensing (QS) is a ubiquitous cell-to-cell communication mechanism. Previous studies showed that mainly employs cis-2-dodecenoic acid (BDSF) and N-acyl homoserine lactone (AHL) QS systems to regulate biological functions and virulence. Here, we demonstrate that quinolone signal (PQS) delivered by outer membrane vesicles from or liposome attenuates virulence by targeting the LysR-type regulator ShvR, which regulates the production of the QS signals BDSF and AHL in a. Our results not only suggest the important roles of membrane-enclosed PQS in interspecies and interkingdom communications but also provide a new perspective on the use of functional nanocarriers loaded with QS inhibitors for treating pathogen infections.
Topics: Humans; Quorum Sensing; Virulence; Acyl-Butyrolactones; Liposomes; Bacterial Proteins; Burkholderia cenocepacia; Pseudomonas aeruginosa; Gene Expression Regulation, Bacterial
PubMed: 37796010
DOI: 10.1128/aem.01184-23 -
Nutrition & Metabolism Jun 2023Non-alcoholic steatohepatitis (NASH) is a major contributor to liver cirrhosis and hepatocellular carcinoma. There remains no effective pharmacological therapy. The...
BACKGROUND
Non-alcoholic steatohepatitis (NASH) is a major contributor to liver cirrhosis and hepatocellular carcinoma. There remains no effective pharmacological therapy. The hepatic lipid metabolism and fatty acid β-oxidation are regulated by Perilipin5 (Plin5). However, it is yet unknown how Plin5 affects NASH and the molecular process.
METHODS
High-fat, high-cholesterol and high-fructose (HFHC) diets were used to mimic the progression of NASH in wild type (WT) mice and Plin5 knockout (Plin5 KO) mice. The degree of ferroptosis was measured by detecting the expression of key genes of ferroptosis and the level of lipid peroxide. The degree of NASH was judged by observing the morphology of the liver, detecting the expression of inflammation and fibrosis related genes of liver damage. Plin5 was overexpressed in the liver of mice by tail vein injection of adenovirus, and the process of NASH was simulated by methionine choline deficiency (MCD) diet. The occurrence of ferroptosis and NASH was detected by the same detection method. Targeted lipidomics sequencing was used to detect the difference in free fatty acid expression in the WT Plin5 KO group. Finally, it was verified in cell experiments to further study the effect of free fatty acids on ferroptosis of hepatocytes.
RESULTS
In various NASH models, hepatic Plin5 was dramatically reduced. Plin5 knockout (KO) worsened NASH-associated characteristics in mice given a high-fat/high-cholesterol (HFHC) diet, such as lipid accumulation, inflammation and hepatic fibrosis. It has been shown that ferroptosis is involved in NASH progression. We revealed that Plin5 KO in mice aggravated the degree of ferroptosis in NASH models. Conversely, overexpression of Plin5 significantly alleviated ferroptosis and further ameliorated progression of MCD-induced NASH. Analysis of livers obtained from HFHC diet-fed mice by targeted lipidomics revealed that 11-Dodecenoic acid was significantly decreased in Plin5 KO mice. Addition of 11-Dodecenoia acid to Plin5 knockdown hepatocytes effectively prevented ferroptosis.
CONCLUSION
Our study demonstrates that Plin5 protects against NASH progression by increasing 11-Dodecenoic acid level and further inhibiting ferroptosis, suggesting that Plin5 has therapeutic potential as a target for the management of NASH.
PubMed: 37349836
DOI: 10.1186/s12986-023-00751-2 -
Journal of Agricultural and Food... Mar 2023Plants can recruit beneficial microbes to help improve their fitness under abiotic or biotic stress. Our previous studies found that could enrich beneficial sp. B36 in...
Plants can recruit beneficial microbes to help improve their fitness under abiotic or biotic stress. Our previous studies found that could enrich beneficial sp. B36 in the rhizosphere soil under autotoxic ginsenoside stress. Here, we clarified that ginsenoside stress activated the phenylpropanoid biosynthesis and α-linolenic acid metabolism pathways of roots to increase the secretion of cinnamic acid, 2-dodecenoic acid, and 12-oxo-phytodienoic acid. These metabolites could promote the growth of B36. Importantly, cinnamic acid could simultaneously promote the chemotaxis and growth of B36, enhance the colonization of B36 in the rhizosphere, and eventually increase the survival rate of . Overall, the plants could promote the growth and colonization of beneficial bacteria through key metabolites in root exudates under autotoxin stress. This finding will facilitate the practical application of beneficial bacteria in agricultural production and lead to successful and reproducible biocontrol efficacy by the exogenous addition of key metabolites.
Topics: Transcriptome; Ginsenosides; Plant Roots; Bacteria; Plants; Exudates and Transudates; Rhizosphere; Soil Microbiology
PubMed: 36893094
DOI: 10.1021/acs.jafc.3c00311 -
Applied Microbiology and Biotechnology Apr 2023Biobased polymers derived from plant oils are sustainable alternatives to petro based polymers. In recent years, multienzyme cascades have been developed for the...
Biobased polymers derived from plant oils are sustainable alternatives to petro based polymers. In recent years, multienzyme cascades have been developed for the synthesis of biobased ω-aminocarboxylic acids, which serve as building blocks for polyamides. In this work, we have developed a novel enzyme cascade for the synthesis of 12-aminododeceneoic acid, a precursor for nylon-12, starting from linoleic acid. Seven bacterial ω-transaminases (ω-TAs) were cloned, expressed in Escherichia coli and successfully purified by affinity chromatography. Activity towards the oxylipin pathway intermediates hexanal and 12-oxododecenoic acid in their 9(Z) and 10(E) isoforms was demonstrated for all seven transaminases in a coupled photometric enzyme assay. The highest specific activities were obtained with ω-TA from Aquitalea denitrificans (TR), with 0.62 U mg for 12-oxo-9(Z)-dodecenoic acid, 0.52 U mg for 12-oxo-10(E)-dodecenoic acid and 1.17 U mg for hexanal. A one-pot enzyme cascade was established with TR and papaya hydroperoxide lyase (HPL), reaching conversions of 59% according to LC-ELSD quantification. Starting from linoleic acid, up to 12% conversion to 12-aminododecenoic acid was achieved with a 3-enzyme cascade comprising soybean lipoxygenase (LOX-1), HPL and TR. Higher product concentrations were achieved by the consecutive addition of enzymes compared to simultaneous addition at the beginning. KEY POINTS: • Seven ω-transaminases converted 12-oxododecenoic acid into its corresponding amine. • A three-enzyme cascade with lipoxygenase, hydroperoxide lyase, and ω-transaminase was established for the first time. • A one-pot transformation of linoleic acid to 12-aminododecenoic acid, a precursor of nylon-12 was achieved.
Topics: Transaminases; Oxylipins; Linoleic Acid; Lipoxygenase; Polymers
PubMed: 36807735
DOI: 10.1007/s00253-023-12422-6 -
Applied Biochemistry and Biotechnology Dec 2022Hydroperoxide lyases (HPLs) catalyze the splitting of 13S-hydroperoxyoctadecadienoic acid (13S-HPODE) into the green note flavor hexanal and 12-oxo-9(Z)-dodecenoic acid,...
Hydroperoxide lyases (HPLs) catalyze the splitting of 13S-hydroperoxyoctadecadienoic acid (13S-HPODE) into the green note flavor hexanal and 12-oxo-9(Z)-dodecenoic acid, which is not yet used industrially. Here, HPL from Carica papaya (HPL) was cloned and functionally expressed in Escherichia coli to investigate synthesis of 12-oxo-9(Z)-dodecenoic acid in detail. To improve the low catalytic activity of full-length HPL, the hydrophobic, non-conserved N-terminal sequence was deleted. This enhanced enzyme activity from initial 10 to 40 U/l. With optimization of solubilization buffer, expression media enzyme activity was increased to 2700 U/l. The tetrameric enzyme was produced in a 1.5 l fermenter and enriched by affinity chromatography. The enzyme preparation possesses a slightly acidic pH optimum and a catalytic efficiency (k/K) of 2.73 × 10 s·M towards 13S-HPODE. Interestingly, HPL could be applied for the synthesis of 12-oxo-9(Z)-dodecenoic acid, and 1 mM of 13S-HPODE was transformed in just 10 s with a yield of 90%. At protein concentrations of 10 mg/ml, the slow formation of the 10(E)-isomer traumatin was observed, pointing to a non-enzymatic isomerization process. Bearing this in mind, a one-pot enzyme cascade starting from safflower oil was developed with consecutive addition of Pseudomonas fluorescens lipase, Glycine max lipoxygenase (LOX-1), and HPL. A yield of 43% was obtained upon fast extraction of the reaction mixtures after 1 min of HPL reaction. This work provides first insights into an enzyme cascade synthesis of 12-oxo-9(Z)-dodecenoic acid, which may serve as a bifunctional precursor for bio-based polymer synthesis.
Topics: Carica; Polymers; Aldehyde-Lyases; Cytochrome P-450 Enzyme System
PubMed: 35904676
DOI: 10.1007/s12010-022-04095-0 -
International Journal of Molecular... Jul 2022The genome of the neotropical fruit bat was recently sequenced, revealing an unexpected gene encoding a plant-like protein, CYP74C44, which shares ca. 90% sequence...
The genome of the neotropical fruit bat was recently sequenced, revealing an unexpected gene encoding a plant-like protein, CYP74C44, which shares ca. 90% sequence identity with the putative CYP74C of . The preparation and properties of the recombinant CYP74C44 are described in the present work. The CYP74C44 enzyme was found to be active against the 13- and 9-hydroperoxides of linoleic and α-linolenic acids (13-HPOD, 13-HPOT, 9-HPOD, and 9-HPOT, respectively), as well as the 15-hydroperoxide of eicosapentaenoic acid (15-HPEPE). All substrates studied were specifically transformed into chain cleavage products that are typical for hydroperoxide lyases (HPLs). The HPL chain cleavage reaction was validated by the identification of NaBH-reduced products (Me/TMS) of 15-HPEPE and 13- and 9-hydroperoxides as (all-)-14-hydroxy-5,8,11-tetradecatrienoic, (9)-12-hydroxy-9-dodecenoic, and 9-hydroxynonanoic acids (Me/TMS), respectively. Thus, CYP74C44 possessed the HPL activity that is typical for the CYP74C subfamily proteins.
Topics: Aldehyde-Lyases; Animals; Chiroptera; Cytochrome P-450 Enzyme System; Hydrogen Peroxide; Plant Proteins; Substrate Specificity
PubMed: 35887355
DOI: 10.3390/ijms23148009