Carotenoids are valuable pigments that have been widely used in food,pharmaceutical,animal breeding and cosmetics industries.Due to the increasing demand for carotenoids of natural origin,the trend for production of c...Carotenoids are valuable pigments that have been widely used in food,pharmaceutical,animal breeding and cosmetics industries.Due to the increasing demand for carotenoids of natural origin,the trend for production of carotenoids by red yeast has become popular.Strain Rhodotorula mucilaginosa CYJ03 was isolated from northern Yellow Sea of China for its carotenoid producing potential.It was found that the whole genome of CYJ03 was 19.03 Mb in size and contained 6301 protein-coding genes including a gene cluster for the carotenoids biosynthesis.The genome sequence would be valuable for exploring the potential biological properties of CYJ03,as well as for facilitating the molecular genetic analysis and the manipulation of carotenoids accumulation in this strain,and for the development of it as an engineered host for carotenoid production.展开更多
Objective:To evaluate the in vitro activity and synergism of the combinations of natural honey and curcuma starch against Rhodotorula mucilaginosa in correlation with total phenolic,flavonoid contents,and diastase act...Objective:To evaluate the in vitro activity and synergism of the combinations of natural honey and curcuma starch against Rhodotorula mucilaginosa in correlation with total phenolic,flavonoid contents,and diastase activity.Methods:The Folin-Ciocalteu test was used to determine the total polyphenols content and the flavonoid content was analyzed using by the aluminum chloride method.The antifungal activity of the natural honey,determined by an agar well diffusion assay and agar incorporation method.Results:Total phenolic content varied from(63.93±0.11)to(95.36±6.08)mg GAE/100 g honey as gallic acid equivalent.Total flavonoids content varied from(5.41±0.04)to(9.94±0.54)mg CE/100g.Diastase activity values were between(7.3±2.8)and(26±2.8).The zone inhibition diameter for the six honey samples without starch ranged between 6 and 20 mm.When starch was mixed with honey and then added to well,a zone inhibition increase diameter 7 and 21 mm.The percentage increase was noticed with each variety and it ranged between 5%and 62.5%.The minimal inhibitory concentrations for the six varieties of honey without starch against Rhodotorula mucilaginosa ranged between 28%and 36%(v/v).When starch was incubated with honey and then added to media,a minimal inhibitory concentration drop has been noticed with each variety.It ranged between 6.66%and 20%(w/v).No significant correlation was established between diastase activity and bioactive compounds.Conclusions:The mixture of curcuma starch and honey could lead to the development of new combination antibiotics against Rhodotorula展开更多
Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promisin...Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promising alternative route compared to conventional methods such as chemical synthesis or phytoextraction.The red yeast Rhodotorula mucilaginosa has been widely studied due to its natural production capacity of carotenoid and lipids,indicating a strong endogenous isoprene pathway with readily available metabolic intermediates.This study constructed several engineered strains of R.mucilaginosa with the aim of producing different terpenoids.Monoterpeneα-terpineol was produced by expressing theα-terpineol synthase from Vitis vinifera.The titer ofα-terpineol was further enhanced to 0.39 mg/L by overexpressing the endogenous rate-limiting gene of the MVA pathway.Overexpression ofα-farnesene synthase from Malus domestica,in combination with MVA pathway rate-limiting gene resulted in significant increase inα-farnesene production,reaching a titer of 822 mg/L.The carotenoid degradation productβ-ionone was produced at a titer of 0.87 mg/L by expressing theβ-ionone synthase from Petunia hybrida.This study demonstrates the potential of R.mucilaginosa as a platform host for the direct biosynthesis of various terpenoids and provides insights for further development of such platforms.展开更多
Objective:To study carbon and nitrogen utilization pattern and arthrospore formation in a psychrotolerant yeast isolate Rhodotorula mucilaginosa(R.mucilaginosa)BPT1.Methods:Growth of the yeast on minimal synthetic med...Objective:To study carbon and nitrogen utilization pattern and arthrospore formation in a psychrotolerant yeast isolate Rhodotorula mucilaginosa(R.mucilaginosa)BPT1.Methods:Growth of the yeast on minimal synthetic medium supplemented with various carbon and nitrogen compounds as sole carbon or nitrogen source has been studied.Various physico-chemical parameters such as pH,restricted oxygen supply,temperatures,media composition and presence of methionine were tested to examine their effect on arthrospore formation by this known opportunistic pathogen.Results:The psychrotolerant isolate BPT1 identified on the basis of D1/D2 domain of large rDNA sequence characteristics as R.mucilaginosa showed some deviation in carbon and nitrogen utilization patterns from those of other strains of R.mucilaginosa in the CBS data base.Intriguingly,the isolate produced sub-surface hyphal rays around its colony at lower temperatures(4℃and 20℃)on PDA medium;the ray was found to be linearly arranged arthrospores.The arthrospore was not produced in liquid medium,or in presence of methionine or under micro-aerobic condition or at higher temperature.Conclusions:The investigation showed a novel feature i.e.arthrospore was formed by this yeast isolate under specific set of conditions.The results reiterated that only physiological and morphological characteristics were not sufficient to identify a yeast.The ability of R.mucilaginosa to form arthrospores seems to be an adaptive feature in response to extreme environmental condition,and represents adaptive ability having something to do with its ubiquity.展开更多
基金supported by the Postdoctoral Applied Re-search Project of Qingdao
文摘Carotenoids are valuable pigments that have been widely used in food,pharmaceutical,animal breeding and cosmetics industries.Due to the increasing demand for carotenoids of natural origin,the trend for production of carotenoids by red yeast has become popular.Strain Rhodotorula mucilaginosa CYJ03 was isolated from northern Yellow Sea of China for its carotenoid producing potential.It was found that the whole genome of CYJ03 was 19.03 Mb in size and contained 6301 protein-coding genes including a gene cluster for the carotenoids biosynthesis.The genome sequence would be valuable for exploring the potential biological properties of CYJ03,as well as for facilitating the molecular genetic analysis and the manipulation of carotenoids accumulation in this strain,and for the development of it as an engineered host for carotenoid production.
基金Supported by the Algerian Ministry of the higher education and scientific research.CNEPRU project approved in 2011/2013(Grant No.F023 2009/009)
文摘Objective:To evaluate the in vitro activity and synergism of the combinations of natural honey and curcuma starch against Rhodotorula mucilaginosa in correlation with total phenolic,flavonoid contents,and diastase activity.Methods:The Folin-Ciocalteu test was used to determine the total polyphenols content and the flavonoid content was analyzed using by the aluminum chloride method.The antifungal activity of the natural honey,determined by an agar well diffusion assay and agar incorporation method.Results:Total phenolic content varied from(63.93±0.11)to(95.36±6.08)mg GAE/100 g honey as gallic acid equivalent.Total flavonoids content varied from(5.41±0.04)to(9.94±0.54)mg CE/100g.Diastase activity values were between(7.3±2.8)and(26±2.8).The zone inhibition diameter for the six honey samples without starch ranged between 6 and 20 mm.When starch was mixed with honey and then added to well,a zone inhibition increase diameter 7 and 21 mm.The percentage increase was noticed with each variety and it ranged between 5%and 62.5%.The minimal inhibitory concentrations for the six varieties of honey without starch against Rhodotorula mucilaginosa ranged between 28%and 36%(v/v).When starch was incubated with honey and then added to media,a minimal inhibitory concentration drop has been noticed with each variety.It ranged between 6.66%and 20%(w/v).No significant correlation was established between diastase activity and bioactive compounds.Conclusions:The mixture of curcuma starch and honey could lead to the development of new combination antibiotics against Rhodotorula
基金National Key Research and Development Program of China(2021YFA0910600)National Natural Science Foundation of China(22308350,22238010)+1 种基金Liaoning Revitalization Talents Program(XLYC2002089)Science and Technology Bureau of Dalian City(2021RT04).
文摘Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promising alternative route compared to conventional methods such as chemical synthesis or phytoextraction.The red yeast Rhodotorula mucilaginosa has been widely studied due to its natural production capacity of carotenoid and lipids,indicating a strong endogenous isoprene pathway with readily available metabolic intermediates.This study constructed several engineered strains of R.mucilaginosa with the aim of producing different terpenoids.Monoterpeneα-terpineol was produced by expressing theα-terpineol synthase from Vitis vinifera.The titer ofα-terpineol was further enhanced to 0.39 mg/L by overexpressing the endogenous rate-limiting gene of the MVA pathway.Overexpression ofα-farnesene synthase from Malus domestica,in combination with MVA pathway rate-limiting gene resulted in significant increase inα-farnesene production,reaching a titer of 822 mg/L.The carotenoid degradation productβ-ionone was produced at a titer of 0.87 mg/L by expressing theβ-ionone synthase from Petunia hybrida.This study demonstrates the potential of R.mucilaginosa as a platform host for the direct biosynthesis of various terpenoids and provides insights for further development of such platforms.
基金supported by Madhya Pradesh Council of Science and Technology,Bhopal(MP)(Grant No.3902/CST/R&D/2011).
文摘Objective:To study carbon and nitrogen utilization pattern and arthrospore formation in a psychrotolerant yeast isolate Rhodotorula mucilaginosa(R.mucilaginosa)BPT1.Methods:Growth of the yeast on minimal synthetic medium supplemented with various carbon and nitrogen compounds as sole carbon or nitrogen source has been studied.Various physico-chemical parameters such as pH,restricted oxygen supply,temperatures,media composition and presence of methionine were tested to examine their effect on arthrospore formation by this known opportunistic pathogen.Results:The psychrotolerant isolate BPT1 identified on the basis of D1/D2 domain of large rDNA sequence characteristics as R.mucilaginosa showed some deviation in carbon and nitrogen utilization patterns from those of other strains of R.mucilaginosa in the CBS data base.Intriguingly,the isolate produced sub-surface hyphal rays around its colony at lower temperatures(4℃and 20℃)on PDA medium;the ray was found to be linearly arranged arthrospores.The arthrospore was not produced in liquid medium,or in presence of methionine or under micro-aerobic condition or at higher temperature.Conclusions:The investigation showed a novel feature i.e.arthrospore was formed by this yeast isolate under specific set of conditions.The results reiterated that only physiological and morphological characteristics were not sufficient to identify a yeast.The ability of R.mucilaginosa to form arthrospores seems to be an adaptive feature in response to extreme environmental condition,and represents adaptive ability having something to do with its ubiquity.
