Trans-trans farnesol （tt-farnesol） is a bioactive sesquiterpene alcohol commonly found in propolis （a beehive product） and citrus fruits, which disrupts the ability of Streptococcus mutans （S. mutans） to form vi...Trans-trans farnesol （tt-farnesol） is a bioactive sesquiterpene alcohol commonly found in propolis （a beehive product） and citrus fruits, which disrupts the ability of Streptococcus mutans （S. mutans） to form virulent biofilms. In this study, we investigated whether tt-farnesol affects cell-membrane function, acid production and/or acid tolerance by planktonic cells and biofilms of S. mutans UA159. Furthermore, the influence of the agent on S. mutans gene expression and ability to form biofilms in the presence of other oral bacteria （Streptococcus oralis （S. oralis） 35037 and Actinomyces naeslundii （.4. naeslundil） 12104） was also examined. In general, tt-farnesol （1 mmol-L-1） significantly increased the membrane proton permeability and reduced glycolytie activity of S. mutans in the planktonic state and in biofilms （P〈0.05）. Moreover, topical applications of 1 mmol-L＂l tt-farnesol twice daily （1 min exposure/treatment） reduced biomass accumulation and prevented ecological shifts towards S. mutans dominance within mixed-species biofilms after introduction of 1% sucrose. S. oralis （a non-cariogenie organism） became the major species after treatments with tt-farnesol, whereas vehicle-treated biofilms contained mostly S. mutans （〉90% of total bacterial population）. However, the agent did not affect significantly the expression of S. mutans genes involved in acidogenicity, acid tolerance or polysaccharide synthesis in the treated biofilms. Our data indicate that tt-farnesoi may affect the competi- tiveness of S. mutans in a mixed-species environment by primarily disrupting the membrane function and physiology of this bacterium. This naturally occurring terpenoid could be a potentially useful adjunctive agent to the current anti-biofilm/anti-caries chemotherapeutic strategies.展开更多
Sesquiterpenoids play an import role in the direct or indirect defense of plants.Farnesyl pyrophosphate synthases(FPSs)catalyze the biosynthesis of farnesyl pyrophosphate,which is a key precursor of farnesol and(E)-β...Sesquiterpenoids play an import role in the direct or indirect defense of plants.Farnesyl pyrophosphate synthases(FPSs)catalyze the biosynthesis of farnesyl pyrophosphate,which is a key precursor of farnesol and(E)-β-farnesene.In the current study,two FPS genes in Gossypium hirsutum,GhFPS1 and GhFPS2,were heterologously cloned and functionally characterized in a greenhouse setting.The open reading frames for full-length GhFPS1 and GhFPS2 were each 1029 nucleotides,and encoded two proteins of 342 amino acids with molecular weights of 39.4 kDa.The deduced amino acid sequences of GhFPS1–2 showed high identity to FPSs of other plants.Quantitative real-time PCR analysis revealed that GhFPS1 and GhFPS2 were highly expressed in G.hirsutum leaves,and were upregulated in methyl jasmonate(MeJA)-,methyl salicylate(MeSA)-and aphid infestation-treated cotton plants.The recombinant proteins of either GhFPS1 or GhFPS2 plus calf intestinal alkaline phosphatase could convert geranyl diphosphate(GPP)or isopentenyl diphosphate(IPP)to one major product,farnesol.Moreover,in electrophysiological response and Y-tube olfactometer assays,farnesol showed obvious attractiveness to female Aphidius gifuensis,which is an important parasitic wasp of aphids.Our findings suggest that two GhFPSs are involved in farnesol biosynthesis and they play a crucial role in indirect defense of cotton against aphid infestation.展开更多
Streptococcus mutans is a primary etiological agent of dental caries.Farnesol,as a potential antimicrobial agent,inhibits the development of S.mutans biofilm.In this study,we hypothesized that farnesol inhibits caries...Streptococcus mutans is a primary etiological agent of dental caries.Farnesol,as a potential antimicrobial agent,inhibits the development of S.mutans biofilm.In this study,we hypothesized that farnesol inhibits caries development in vitro and interferes with biofilm fonnation by regulating virulence-associated gene expression.The inhibitory effects of farnesol to S.mutans biofilms on enamel surfaces were investigated by determining micro-hardness and calcium measurements.Additionally,the morphological changes of S.mutans biofilms were compared using field emission scanning electron microscopy and confocal laser scanning microscopy,and the vitality and oxygen sensitivity of S.mutans biofilms were compared using MTT assays.To investigate the molecular mechanisms of farnesol＇s effects,expressions of possible target genes luxS,brpA,ffh,recA,nth,and smx were analyzed using reverse-transcription polymerase chain reaction（PCR） and quantitative PCR.Farnesol-treated groups exhibited significantly higher micro-hardness on the enamel surface and lower calcium concentration of the supernatants as compared to the-untreated control.Microscopy revealed that a thinner film with less extracellular matrix formed in the farnesol-treated groups.As compared to the-untreated control,farnesol inhibited biofilm formation by 26.4%with500 μmol/L and by 37.1%with 1,000 μmol/L（P〈 0.05）.Last,decreased transcription levels of luxS,brpA,ffh,recA,nth,and smx genes were expressed in farnesol-treated biofilms.In vitro farnesol inhibits caries development and S.mutans biofilm formation.The regulation of luxS,brpA,ffh,recA,nth,and smx genes may contribute to the inhibitory effects of farnesol.展开更多
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"> Farnesol is added to numerous consumer products</span><span st...<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"> Farnesol is added to numerous consumer products</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">that inten</span><span style="font-family:Verdana;">tionally, or inadvertently come in contact with tissues that may harbor </span><span style="font-family:Verdana;">the opportunistic yeast, </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;">. </span><b><span style="font-family:Verdana;">Objective:</span></b><span style="font-family:Verdana;"> This study explores biological consequences of the exposure of </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> from community infecti</span><span style="font-family:Verdana;">ons or from a panel of antifungal drug resistant organis</span><span style="font-family:Verdana;">ms on growth and survival of these organisms when exposed to farnesol. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> ATCC supplied </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> from the MP8 drug resistance panel and an additional 1</span><span><span style="font-family:Verdana;">2 strains of community-acquired </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> were c</span></span><span style="font-family:Verdana;">ultured in the presence of farnesol. With standard micobiologic techniques and flow cytometry evaluation, a series of experiments considered growth, morphology, viability and entrance into the quiescent persister phenotype of </span><i><span style="font-family:Verdana;">Candida</span></i></span><i><span style="font-family:;" "=""> </span></i><span style="font-family:;" "=""><span style="font-family:Verdana;">with emphasis on differences between drug resistant and community organisms. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Di</span><span style="font-family:Verdana;">fferences growth yield, relative cell size and heat suscep</span><span style="font-family:Verdana;">tibility distinguished the community organisms from the drug-resistant organisms. Using a subset of these organisms, exposure to farnesol resulted in diminished growth, inhibited hyphal growth, diminished cell membrane integrity and increased heat stress susceptibility. Data provided suggest that exposure to farnesol pushes cultures of </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> toward the quiescent persister phenotype. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Exposure of drug resistant and community strains of </span><i><span style="font-family:Verdana;">Candida albican</span><span style="font-family:Verdana;">s</span></i><span style="font-family:Verdana;"> are modestly affected by farnesol</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">in ways that may lessen their </span><span style="font-family:;" "=""><span style="font-family:Verdana;">pathogenic potential. In contrast, the tendency of farnesol to engender greater numbers of quiescent organisms could support persistence of </span><i><span style="font-family:Verdana;">Candida</span></i><span style="font-family:Verdana;">.</span></span>展开更多
Farnesol is a C15 isoprenyl alcohol generated from the hydrolysis of farnesyl diphosphate under the action of farnesol synthase in plants.Although this sesquiterpenoid alcohol has been exploited in a wide variety of i...Farnesol is a C15 isoprenyl alcohol generated from the hydrolysis of farnesyl diphosphate under the action of farnesol synthase in plants.Although this sesquiterpenoid alcohol has been exploited in a wide variety of industrial applications,serious discussions on the possible use of this agent in disease treatment have been scant until now.In this article,we review the current understanding of the physiological properties of farnesol and the potential use of the agent as a candidate for treatment development.In fact,since the turn of the last century,farnesol has been found not only to trigger apoptosis in tumor cells but also to be able to function as a quorum-sensing molecule in Candida albicans to influence infection dynamics.By offering a snapshot of recent advances in research on farnesol,it is expected that this article can provide more insights into future research on farnesol for the development of different treatment strategies.展开更多
Our previous research found that farnesol,a fungal quorum-sensing molecule,may simultaneously regulate the yeast-to-hypha transition and promote squalene biosynthesis in Saccharomycopsis fibuligera.To confirm this,in ...Our previous research found that farnesol,a fungal quorum-sensing molecule,may simultaneously regulate the yeast-to-hypha transition and promote squalene biosynthesis in Saccharomycopsis fibuligera.To confirm this,in this study,we conducted farnesol exposure experiments and analyzed the changes in morphology and squalene content of S.fibuligera.The structure and function of S.fibuligera squalene synthase(SfSQS)were analyzed using molecular docking simulations and protein expression.Metabolomics and tandem mass tag(TMT)-labeling proteomics were employed to investigate the mechanisms underlying farnesol-induced morphogenesis and metabolic changes in S.fibuligera.The results showed that treatments with 50μmol/L and 100μmol/L farnesol significantly increased squalene content by over 1.67-fold in S.fibuligera.High concentrations of farnesol promoted hyphal elongation while suppressing yeast-form cell growth in S.fibuligera.Analysis of SfSQS demonstrated that it forms stable binding complexes with farnesyl pyrophosphate(FPP)and presqualene diphosphate and exhibits catalytic activity in converting FPP to squalene.Metabolomic and proteomic analyses revealed that farnesol enhances squalene biosynthesis and regulates sterol metabolism by modulating the mevalonate pathway in S.fibuligera.Furthermore,the morphologic changes in S.fibuligera are linked to the regulation of its response to farnesol-induced stresses,including oxidative stress and DNA replication stress.This research advances our understanding of quorum sensing in dimorphic yeasts and provides a theoretical basis for yeast-based squalene production.展开更多
Farnesol(FOH),a prized sesquiterpenoid alcohol,is at the core of this study,which outlines a synthetic biology strategy to significantly boost its production for use in flavors,fragrances,pharmaceuticals,and biofuels....Farnesol(FOH),a prized sesquiterpenoid alcohol,is at the core of this study,which outlines a synthetic biology strategy to significantly boost its production for use in flavors,fragrances,pharmaceuticals,and biofuels.We constructed an efficient FOH biosynthetic pathway in Serratia marcescens,leveraging rational engineering strategies to optimize its production.Initially,we introduced a heterologous mevalonate(MVA)pathway into S.marcescens for FOH biosynthesis.We then screened different sources of monophosphate phosphatases and performed rational modifications to enhance their activity.Computational simulations were employed to model the SmAp-FP complex,guiding protein engineering efforts.The engineered strain S.marcescens SPF6_L2 achieved a FOH titer of 457.3±23.1 mg/L in shake flask fermentation,which was further scaled up to 1784.3 mg/L in a 5 L fermenter.This represents one of the highest reported titers of FOH production in microorganisms to date.Our approach integrates genetic engineering,enzyme optimization,and bioprocess design to efficiently biosynthesize FOH.It sets the stage for future research on optimizing S.marcescens metabolic pathways for enhanced terpenoid biosynthesis.展开更多
Background:The phenotypic switching of Candida spp.plays an important role in the development of vulvovaginal candidiasis(VVC).Farnesol,as a quorum-sensing molecule in Candida albicans,has the ability to prevent yeast...Background:The phenotypic switching of Candida spp.plays an important role in the development of vulvovaginal candidiasis(VVC).Farnesol,as a quorum-sensing molecule in Candida albicans,has the ability to prevent yeast-to-hyphal conversion in vitro.However,the mechanism underlying this ability is unclear.This study aimed to investigate changes in protein levels to better understand how farnesol impacts processes contributing to VVC.Methods:The isobaric tag for relative and absolute quantitation technique was used to detect protein expression in C.albicans strain SC5314(ATCC MYA-2876)with or without farnesol exposure.Proteins with a threshold fold change greater than 1.5 were screened and considered differentially expressed proteins.All the altered proteins were analyzed using Gene Ontology annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)annotation,and metabolic pathway annotation.Results:Between the farnesol-exposed group and the farnesol-unexposd group,we detected 297 altered proteins among all 2047 tested proteins based on a threshold fold change of more than 1.5(P<0.05).Eighty-seven of the 297 altered proteins exhibited metabolic enzyme activity and participated in 85 metabolic pathways according to KEGG pathway analysis.Most of these metabolic pathways were associated with central carbon metabolism processes.In the sterol synthesis pathway,which involves the synthesis of farnesol,ERG25(methylsterol monooxygenase)and ERG4(delta 24(24(1))-sterol reductase)were both down-regulated in the farnesol-exposed group.All six altered proteases associated with the oxidative phosphorylation process were down-regulated in the farnesol-exposed group relative to the farnesol-unexposed group.Conclusions:The mechanisms underlying farnesol-induced phenotype switching involves the adjustment of metabolic activities and epigenetic modification.Exogenous farnesol had an evident,but non-deterministic effect on the synthesis of ergosterol.The potential drug activity of farnesol warrants further investigation.展开更多
基金supported by IADR/GSK Innovation in Oral Care Award, USPHS Research grant 1R01DE 018023 from the National Institute of Dental and Craniofacial Research (National Institutes of Health)Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (2009-0071090)
文摘Trans-trans farnesol （tt-farnesol） is a bioactive sesquiterpene alcohol commonly found in propolis （a beehive product） and citrus fruits, which disrupts the ability of Streptococcus mutans （S. mutans） to form virulent biofilms. In this study, we investigated whether tt-farnesol affects cell-membrane function, acid production and/or acid tolerance by planktonic cells and biofilms of S. mutans UA159. Furthermore, the influence of the agent on S. mutans gene expression and ability to form biofilms in the presence of other oral bacteria （Streptococcus oralis （S. oralis） 35037 and Actinomyces naeslundii （.4. naeslundil） 12104） was also examined. In general, tt-farnesol （1 mmol-L-1） significantly increased the membrane proton permeability and reduced glycolytie activity of S. mutans in the planktonic state and in biofilms （P〈0.05）. Moreover, topical applications of 1 mmol-L＂l tt-farnesol twice daily （1 min exposure/treatment） reduced biomass accumulation and prevented ecological shifts towards S. mutans dominance within mixed-species biofilms after introduction of 1% sucrose. S. oralis （a non-cariogenie organism） became the major species after treatments with tt-farnesol, whereas vehicle-treated biofilms contained mostly S. mutans （〉90% of total bacterial population）. However, the agent did not affect significantly the expression of S. mutans genes involved in acidogenicity, acid tolerance or polysaccharide synthesis in the treated biofilms. Our data indicate that tt-farnesoi may affect the competi- tiveness of S. mutans in a mixed-species environment by primarily disrupting the membrane function and physiology of this bacterium. This naturally occurring terpenoid could be a potentially useful adjunctive agent to the current anti-biofilm/anti-caries chemotherapeutic strategies.
基金This work was supported by the National Natural Science Foundation of China(31772176,31672038 and 31621064)and the National Key Research and Development Program of China(2017YFDO201900 and 2017YFD0200400).
文摘Sesquiterpenoids play an import role in the direct or indirect defense of plants.Farnesyl pyrophosphate synthases(FPSs)catalyze the biosynthesis of farnesyl pyrophosphate,which is a key precursor of farnesol and(E)-β-farnesene.In the current study,two FPS genes in Gossypium hirsutum,GhFPS1 and GhFPS2,were heterologously cloned and functionally characterized in a greenhouse setting.The open reading frames for full-length GhFPS1 and GhFPS2 were each 1029 nucleotides,and encoded two proteins of 342 amino acids with molecular weights of 39.4 kDa.The deduced amino acid sequences of GhFPS1–2 showed high identity to FPSs of other plants.Quantitative real-time PCR analysis revealed that GhFPS1 and GhFPS2 were highly expressed in G.hirsutum leaves,and were upregulated in methyl jasmonate(MeJA)-,methyl salicylate(MeSA)-and aphid infestation-treated cotton plants.The recombinant proteins of either GhFPS1 or GhFPS2 plus calf intestinal alkaline phosphatase could convert geranyl diphosphate(GPP)or isopentenyl diphosphate(IPP)to one major product,farnesol.Moreover,in electrophysiological response and Y-tube olfactometer assays,farnesol showed obvious attractiveness to female Aphidius gifuensis,which is an important parasitic wasp of aphids.Our findings suggest that two GhFPSs are involved in farnesol biosynthesis and they play a crucial role in indirect defense of cotton against aphid infestation.
基金National Natural Sciences Foundation of China (Grant No.81271151 and Grant No.81371156)Jiangsu Qinglan Project Foundation(2012)The Foundation of the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD,2014-37)
文摘Streptococcus mutans is a primary etiological agent of dental caries.Farnesol,as a potential antimicrobial agent,inhibits the development of S.mutans biofilm.In this study,we hypothesized that farnesol inhibits caries development in vitro and interferes with biofilm fonnation by regulating virulence-associated gene expression.The inhibitory effects of farnesol to S.mutans biofilms on enamel surfaces were investigated by determining micro-hardness and calcium measurements.Additionally,the morphological changes of S.mutans biofilms were compared using field emission scanning electron microscopy and confocal laser scanning microscopy,and the vitality and oxygen sensitivity of S.mutans biofilms were compared using MTT assays.To investigate the molecular mechanisms of farnesol＇s effects,expressions of possible target genes luxS,brpA,ffh,recA,nth,and smx were analyzed using reverse-transcription polymerase chain reaction（PCR） and quantitative PCR.Farnesol-treated groups exhibited significantly higher micro-hardness on the enamel surface and lower calcium concentration of the supernatants as compared to the-untreated control.Microscopy revealed that a thinner film with less extracellular matrix formed in the farnesol-treated groups.As compared to the-untreated control,farnesol inhibited biofilm formation by 26.4%with500 μmol/L and by 37.1%with 1,000 μmol/L（P〈 0.05）.Last,decreased transcription levels of luxS,brpA,ffh,recA,nth,and smx genes were expressed in farnesol-treated biofilms.In vitro farnesol inhibits caries development and S.mutans biofilm formation.The regulation of luxS,brpA,ffh,recA,nth,and smx genes may contribute to the inhibitory effects of farnesol.
文摘<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"> Farnesol is added to numerous consumer products</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">that inten</span><span style="font-family:Verdana;">tionally, or inadvertently come in contact with tissues that may harbor </span><span style="font-family:Verdana;">the opportunistic yeast, </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;">. </span><b><span style="font-family:Verdana;">Objective:</span></b><span style="font-family:Verdana;"> This study explores biological consequences of the exposure of </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> from community infecti</span><span style="font-family:Verdana;">ons or from a panel of antifungal drug resistant organis</span><span style="font-family:Verdana;">ms on growth and survival of these organisms when exposed to farnesol. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> ATCC supplied </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> from the MP8 drug resistance panel and an additional 1</span><span><span style="font-family:Verdana;">2 strains of community-acquired </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> were c</span></span><span style="font-family:Verdana;">ultured in the presence of farnesol. With standard micobiologic techniques and flow cytometry evaluation, a series of experiments considered growth, morphology, viability and entrance into the quiescent persister phenotype of </span><i><span style="font-family:Verdana;">Candida</span></i></span><i><span style="font-family:;" "=""> </span></i><span style="font-family:;" "=""><span style="font-family:Verdana;">with emphasis on differences between drug resistant and community organisms. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Di</span><span style="font-family:Verdana;">fferences growth yield, relative cell size and heat suscep</span><span style="font-family:Verdana;">tibility distinguished the community organisms from the drug-resistant organisms. Using a subset of these organisms, exposure to farnesol resulted in diminished growth, inhibited hyphal growth, diminished cell membrane integrity and increased heat stress susceptibility. Data provided suggest that exposure to farnesol pushes cultures of </span><i><span style="font-family:Verdana;">Candida albicans</span></i><span style="font-family:Verdana;"> toward the quiescent persister phenotype. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Exposure of drug resistant and community strains of </span><i><span style="font-family:Verdana;">Candida albican</span><span style="font-family:Verdana;">s</span></i><span style="font-family:Verdana;"> are modestly affected by farnesol</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">in ways that may lessen their </span><span style="font-family:;" "=""><span style="font-family:Verdana;">pathogenic potential. In contrast, the tendency of farnesol to engender greater numbers of quiescent organisms could support persistence of </span><i><span style="font-family:Verdana;">Candida</span></i><span style="font-family:Verdana;">.</span></span>
文摘Farnesol is a C15 isoprenyl alcohol generated from the hydrolysis of farnesyl diphosphate under the action of farnesol synthase in plants.Although this sesquiterpenoid alcohol has been exploited in a wide variety of industrial applications,serious discussions on the possible use of this agent in disease treatment have been scant until now.In this article,we review the current understanding of the physiological properties of farnesol and the potential use of the agent as a candidate for treatment development.In fact,since the turn of the last century,farnesol has been found not only to trigger apoptosis in tumor cells but also to be able to function as a quorum-sensing molecule in Candida albicans to influence infection dynamics.By offering a snapshot of recent advances in research on farnesol,it is expected that this article can provide more insights into future research on farnesol for the development of different treatment strategies.
基金supported by the National Natural Science Foundation of China(32072154)Henan Province Science and Technology Tackling Program(232102111073)the Henan Provincial Association for Science and Technology Talent Support Program(2023HYTP029).
文摘Our previous research found that farnesol,a fungal quorum-sensing molecule,may simultaneously regulate the yeast-to-hypha transition and promote squalene biosynthesis in Saccharomycopsis fibuligera.To confirm this,in this study,we conducted farnesol exposure experiments and analyzed the changes in morphology and squalene content of S.fibuligera.The structure and function of S.fibuligera squalene synthase(SfSQS)were analyzed using molecular docking simulations and protein expression.Metabolomics and tandem mass tag(TMT)-labeling proteomics were employed to investigate the mechanisms underlying farnesol-induced morphogenesis and metabolic changes in S.fibuligera.The results showed that treatments with 50μmol/L and 100μmol/L farnesol significantly increased squalene content by over 1.67-fold in S.fibuligera.High concentrations of farnesol promoted hyphal elongation while suppressing yeast-form cell growth in S.fibuligera.Analysis of SfSQS demonstrated that it forms stable binding complexes with farnesyl pyrophosphate(FPP)and presqualene diphosphate and exhibits catalytic activity in converting FPP to squalene.Metabolomic and proteomic analyses revealed that farnesol enhances squalene biosynthesis and regulates sterol metabolism by modulating the mevalonate pathway in S.fibuligera.Furthermore,the morphologic changes in S.fibuligera are linked to the regulation of its response to farnesol-induced stresses,including oxidative stress and DNA replication stress.This research advances our understanding of quorum sensing in dimorphic yeasts and provides a theoretical basis for yeast-based squalene production.
文摘Farnesol(FOH),a prized sesquiterpenoid alcohol,is at the core of this study,which outlines a synthetic biology strategy to significantly boost its production for use in flavors,fragrances,pharmaceuticals,and biofuels.We constructed an efficient FOH biosynthetic pathway in Serratia marcescens,leveraging rational engineering strategies to optimize its production.Initially,we introduced a heterologous mevalonate(MVA)pathway into S.marcescens for FOH biosynthesis.We then screened different sources of monophosphate phosphatases and performed rational modifications to enhance their activity.Computational simulations were employed to model the SmAp-FP complex,guiding protein engineering efforts.The engineered strain S.marcescens SPF6_L2 achieved a FOH titer of 457.3±23.1 mg/L in shake flask fermentation,which was further scaled up to 1784.3 mg/L in a 5 L fermenter.This represents one of the highest reported titers of FOH production in microorganisms to date.Our approach integrates genetic engineering,enzyme optimization,and bioprocess design to efficiently biosynthesize FOH.It sets the stage for future research on optimizing S.marcescens metabolic pathways for enhanced terpenoid biosynthesis.
基金This work was supported by a grant from the National Natural Science Foundation of China(No.81571394).
文摘Background:The phenotypic switching of Candida spp.plays an important role in the development of vulvovaginal candidiasis(VVC).Farnesol,as a quorum-sensing molecule in Candida albicans,has the ability to prevent yeast-to-hyphal conversion in vitro.However,the mechanism underlying this ability is unclear.This study aimed to investigate changes in protein levels to better understand how farnesol impacts processes contributing to VVC.Methods:The isobaric tag for relative and absolute quantitation technique was used to detect protein expression in C.albicans strain SC5314(ATCC MYA-2876)with or without farnesol exposure.Proteins with a threshold fold change greater than 1.5 were screened and considered differentially expressed proteins.All the altered proteins were analyzed using Gene Ontology annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)annotation,and metabolic pathway annotation.Results:Between the farnesol-exposed group and the farnesol-unexposd group,we detected 297 altered proteins among all 2047 tested proteins based on a threshold fold change of more than 1.5(P<0.05).Eighty-seven of the 297 altered proteins exhibited metabolic enzyme activity and participated in 85 metabolic pathways according to KEGG pathway analysis.Most of these metabolic pathways were associated with central carbon metabolism processes.In the sterol synthesis pathway,which involves the synthesis of farnesol,ERG25(methylsterol monooxygenase)and ERG4(delta 24(24(1))-sterol reductase)were both down-regulated in the farnesol-exposed group.All six altered proteases associated with the oxidative phosphorylation process were down-regulated in the farnesol-exposed group relative to the farnesol-unexposed group.Conclusions:The mechanisms underlying farnesol-induced phenotype switching involves the adjustment of metabolic activities and epigenetic modification.Exogenous farnesol had an evident,but non-deterministic effect on the synthesis of ergosterol.The potential drug activity of farnesol warrants further investigation.
