Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 k...Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively.展开更多
new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The che...new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The chemical structure of compound 1 was determined to be a neopentapyrrole natural product with a 5/5/6 tricyclic skeleton and one amide functional group,by using spectroscopic techniques such as nuclear magnetic resonance(1D/2D NMR)and high-resolution mass spectrometry(HR-ESI-MS).Its structural information indicates that it is probably the shunt product of neopentalenolactone biosynthetic pathway.In antibacterial activity evaluations,compound 1 demonstrated no inhibitory effects against the tested strains including Escherichia coli(DH5a),Staphylococcus aureus,and Bacillus subtilis under the experimental conditions.展开更多
[Objective]To systematically isolate and purify the polysaccharide from the mycelium of Streptomyces rochei D74(SRP),elucidate its fine structure,and evaluate the effect of the purified polysaccharide fraction on the ...[Objective]To systematically isolate and purify the polysaccharide from the mycelium of Streptomyces rochei D74(SRP),elucidate its fine structure,and evaluate the effect of the purified polysaccharide fraction on the growth of Salvia miltiorrhiza hairy roots and the biosynthesis of tanshinones,along with the underlying mechanism.[Methods]The crude polysaccharide was extracted using hot water,which was followed by ethanol precipitation and deproteinization via the Sevag method.Further purification was performed using DEAE-52 anionexchange chromatography and Sephadex G-100 gel filtration chromatography.The physicochemical properties and structural features of the main active fraction,SRP-W-2,were systematically characterized by Fourier transform infrared spectroscopy(FTIR),high performance liquid chromatography-mass spectrometry(HPLC-MS),and nuclear magnetic resonance(NMR).The effects of SRP-W-2 on hairy root growth and the biosynthesis of tanshinones were assessed by measuring biomass,tanshinone content,and the expression levels of key biosynthetic genes.[Results]SRP-W-2 was obtained with a yield of 2.41%.It was primarily composed of glucose and galactose at a molar ratio of 12.53:1.Structural analysis revealed that the backbone of SRP-W-2 consisted of→4)-α-D-Glcp-(1→and→4)-α-D-Galp-(1→residues,with branching points at→4,6)-α-D-Glcp-(1→and→4,6)-α-D-Galp-(1→.The side chain was identified asα-D-Glcp-(1→4)-α-DGlcp-(1→.Bioactivity assays demonstrated that SRP-W-2 significantly enhanced both the biomass of S.miltiorrhiza hairy roots and the accumulation of tanshinones.After 15 d of treatment with 50 mg/L SRP-W-2,the dry weight of the hairy roots increased by 37.52%.Meanwhile,the content of cryptotanshinone(CT),dihydrotanshinone I(DT-I),tanshinone I(T-I),and tanshinone IIA(TIIA)was increased by 19.0-fold,6.4-fold,2.8-fold,and 4.8-fold,respectively.Gene expression analysis further indicated that SRP-W-2 up-regulated key genes involved in the tanshinone biosynthetic pathway,including HMGR,DXS,DXR,and GGPPS.[Conclusion]The polysaccharide fraction SRP-W-2 from S.rochei D74 simultaneously promoted the growth of S.miltiorrhiza hairy roots and the biosynthesis of tanshinones,demonstrating its potential as an effective elicitor.This study provided a new strategy for the utilization and development of S.miltiorrhiza resources.展开更多
[Objective]To confirm the function of the farnesyl diphosphate(FPP)cyclase encoded by orf2064 in Streptomyces exfoliatus UC5319.[Methods]orf2064 was expressed in Escherichia coli,and the recombinant protein was purifi...[Objective]To confirm the function of the farnesyl diphosphate(FPP)cyclase encoded by orf2064 in Streptomyces exfoliatus UC5319.[Methods]orf2064 was expressed in Escherichia coli,and the recombinant protein was purified and assayed with FPP as the substrate.The reaction products were detected by GC-MS.An FPP-overproducing E.coli strain was engineered for heterologous expression of orf2064.The fermentation products were analyzed by GC-MS,and the target compound was isolated and structurally characterized by nuclear magnetic resonance spectroscopy(NMR).In addition,orf2064 was heterologously expressed in Streptomyces,and the fermentation products were analyzed by GC-MS.[Results]GC-MS revealed that both the in vitro reaction of the recombinant protein ORF2064 and the heterologous expression products in E.coli and Streptomyces consistently produced a compound with identical retention time and[M+]of m/z 204.Subsequent isolation,purification,and NMR analysis confirmed this compound as calarene.[Conclusion]The FPP cyclase encoded by orf2064 in S.exfoliatus is identified as an calarene synthase.展开更多
Objective:To investigate the mechanism of anticancer activity of a pigment OR3 from Streptomyces coelicolor in in vitro and in vivo metastatic breast cancer models and to characterize the pigment.Methods:The anticance...Objective:To investigate the mechanism of anticancer activity of a pigment OR3 from Streptomyces coelicolor in in vitro and in vivo metastatic breast cancer models and to characterize the pigment.Methods:The anticancer mechanism was analyzed in MDA-MB-231 cells using MTT,lactate dehydrogenase,caspase,DNA fragmentation,clonogenic,flow cytometry,Western blot,and scratch assays.The effects of OR3 on xenograft mouse models were evaluated by tumor volume measurement,hematological analysis,and histopathological observation.The characterization of OR3 was also performed using gas chromatograohy-mass spectrometry and nuclear magnetic resonance spectroscopy.Results:OR3 exhibited potent cytotoxicity against MDA-MB-231 cells,with no observed effects on HEK-293 cells.Caspase-9 activation was detected in OR3-treated MDA-MB-231 cells.Flow cytometry showed a dose-dependent induction of apoptosis and cell cycle arrest at the sub-G_(1) and S phases.Furthermore,OR3 completely inhibited MDA-MB-231 cell migration and demonstrated anti-proliferative effects by downregulating the protein expression of KPNA2,XPO1,RAB5B,and p38 MAPK.In in vivo studies,OR3 was non-toxic to mice,inhibited tumor xenograft growth,and maintained normal hematological parameters and tissue architecture.Nuclear magnetic resonance spectroscopy demonstrated the presence of a prodigiosin-like compound,while gas chromatography-mass spectrometry analysis identified additional compounds in OR3.Conclusions:Our findings validate OR3 pigment as a promising compound for the treatment of metastatic breast cancer,warranting further studies.展开更多
Long-time fermentation has always been one of the reasons restricting the development of straw biological pulping.This study aimed to develop a novel straw pulp film with shortened solid-state fermentation time with l...Long-time fermentation has always been one of the reasons restricting the development of straw biological pulping.This study aimed to develop a novel straw pulp film with shortened solid-state fermentation time with less than 20%mass loss rate by bio-pulping synergistic treatment of straw fibers with deep eutectic solvent(DES)and Streptomyces rochei(S.rochei).Results illustrated that at 3%S.rochei concentration with 7-day fermentation,both cellulose and hemicellulose enzyme activities of the treated rice straw fiber reached peak values with a fiber mass loss rate of 17.01%.Microstructural morphology revealed that S.rochei colonization initiated on straw surfaces and progressively penetrated internal structures,resulting in surface loosening and distinct disruption of cell wall tissues within vascular bundles in transverse sections.The treated rice straw strip indicated a maximum tensile strength of 46.22 MPa for(Bacteria)BA 3%at day 7,attributed to optimized synergistic effects of microfibril angle(MFA)and cellulose/hemicellulose relative content ratio.The modified straw pulp film exhibited significant enhancement in the tensile index(44.9%increase),burst index(10.3%increase),and tear index(60%increase)compared to untreated groups.This work demonstrated the important role ofDES and S.rochei bio-pulping synergistic treatment in improving rice straw pulp performance,suggesting an eco-friendly,novel,and efficient biomass pretreatment technology for potential application prospects in sustainable agricultural mulching materials.展开更多
In the world of microorganisms,the genud Streptomyces is renowned as a"natural pharmacy".This genus of bacteria is the primary source of clinical antibiotics,with approximately two-thirds of antibiotics deri...In the world of microorganisms,the genud Streptomyces is renowned as a"natural pharmacy".This genus of bacteria is the primary source of clinical antibiotics,with approximately two-thirds of antibiotics derived from it.However,industrial production faces challenges such as low yields and complex regulation.This study introduces the Streptomyces multiplexed artificial control system(SMARTS):a novel"plug-and-play"dynamic regulatory framework integrating trigger,stabilizer,and multiplexer modules.This enables the cross-species,predictable,and scalable production of secondary metabolites.Evolutionary analysis of 521 quorum-sensing receptors revealed conserved DNA-binding domains,informing the design of a universal trigger.SMARTS efficiently and robustly produced baiweimycin in a 120 m3 industrial fermenter,a process validated through a closed-loop pipeline ranging from molecular mechanisms to field applications.Implementing orthogonal control and hierarchical optimization enhances the efficiency of metabolic engineering and sheds light on the evolution of Streptomyces quorum sensing.This breakthrough offers a scalable solution for industrial production and advances synthetic biology,with significant implications for agriculture,pharmaceuticals,and global health.展开更多
[Objective] The research aimed to screen Streptomyces hygroscopicus strains with high production of agricultural antibiotics. [ Method] A strain of S. hygroscopicus was screened from the soil of Hainan Island. After n...[Objective] The research aimed to screen Streptomyces hygroscopicus strains with high production of agricultural antibiotics. [ Method] A strain of S. hygroscopicus was screened from the soil of Hainan Island. After natural screening and consecutive ultraviolet induced mutation twice, S6-7 strain was obtained as the original strain then treated by UV irradiation and streptomycin resistance screening, and finally rescreened through shake-flask fermentation. [Result] 7 better strains were selected by primary screening from 62 single colonies which were picked out randomly. After 3 generations of consecutive cultivation on slant media and rescreening, 5 strains presented obvious forward mutation. The forward mutation rate reached 8.06%, and the largest production increasing rate came up to 25.11%. [Conclusion] By combining streptomycin resistance screening and conventional ultraviolet induced mutation, both the antibiotic-producing capacity and forward mutation screening efficiency of the original strain were greatly enhanced.展开更多
文摘Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively.
基金supported by the National Natural Science Foundation of China(No.22077134)。
文摘new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The chemical structure of compound 1 was determined to be a neopentapyrrole natural product with a 5/5/6 tricyclic skeleton and one amide functional group,by using spectroscopic techniques such as nuclear magnetic resonance(1D/2D NMR)and high-resolution mass spectrometry(HR-ESI-MS).Its structural information indicates that it is probably the shunt product of neopentalenolactone biosynthetic pathway.In antibacterial activity evaluations,compound 1 demonstrated no inhibitory effects against the tested strains including Escherichia coli(DH5a),Staphylococcus aureus,and Bacillus subtilis under the experimental conditions.
文摘[Objective]To systematically isolate and purify the polysaccharide from the mycelium of Streptomyces rochei D74(SRP),elucidate its fine structure,and evaluate the effect of the purified polysaccharide fraction on the growth of Salvia miltiorrhiza hairy roots and the biosynthesis of tanshinones,along with the underlying mechanism.[Methods]The crude polysaccharide was extracted using hot water,which was followed by ethanol precipitation and deproteinization via the Sevag method.Further purification was performed using DEAE-52 anionexchange chromatography and Sephadex G-100 gel filtration chromatography.The physicochemical properties and structural features of the main active fraction,SRP-W-2,were systematically characterized by Fourier transform infrared spectroscopy(FTIR),high performance liquid chromatography-mass spectrometry(HPLC-MS),and nuclear magnetic resonance(NMR).The effects of SRP-W-2 on hairy root growth and the biosynthesis of tanshinones were assessed by measuring biomass,tanshinone content,and the expression levels of key biosynthetic genes.[Results]SRP-W-2 was obtained with a yield of 2.41%.It was primarily composed of glucose and galactose at a molar ratio of 12.53:1.Structural analysis revealed that the backbone of SRP-W-2 consisted of→4)-α-D-Glcp-(1→and→4)-α-D-Galp-(1→residues,with branching points at→4,6)-α-D-Glcp-(1→and→4,6)-α-D-Galp-(1→.The side chain was identified asα-D-Glcp-(1→4)-α-DGlcp-(1→.Bioactivity assays demonstrated that SRP-W-2 significantly enhanced both the biomass of S.miltiorrhiza hairy roots and the accumulation of tanshinones.After 15 d of treatment with 50 mg/L SRP-W-2,the dry weight of the hairy roots increased by 37.52%.Meanwhile,the content of cryptotanshinone(CT),dihydrotanshinone I(DT-I),tanshinone I(T-I),and tanshinone IIA(TIIA)was increased by 19.0-fold,6.4-fold,2.8-fold,and 4.8-fold,respectively.Gene expression analysis further indicated that SRP-W-2 up-regulated key genes involved in the tanshinone biosynthetic pathway,including HMGR,DXS,DXR,and GGPPS.[Conclusion]The polysaccharide fraction SRP-W-2 from S.rochei D74 simultaneously promoted the growth of S.miltiorrhiza hairy roots and the biosynthesis of tanshinones,demonstrating its potential as an effective elicitor.This study provided a new strategy for the utilization and development of S.miltiorrhiza resources.
文摘[Objective]To confirm the function of the farnesyl diphosphate(FPP)cyclase encoded by orf2064 in Streptomyces exfoliatus UC5319.[Methods]orf2064 was expressed in Escherichia coli,and the recombinant protein was purified and assayed with FPP as the substrate.The reaction products were detected by GC-MS.An FPP-overproducing E.coli strain was engineered for heterologous expression of orf2064.The fermentation products were analyzed by GC-MS,and the target compound was isolated and structurally characterized by nuclear magnetic resonance spectroscopy(NMR).In addition,orf2064 was heterologously expressed in Streptomyces,and the fermentation products were analyzed by GC-MS.[Results]GC-MS revealed that both the in vitro reaction of the recombinant protein ORF2064 and the heterologous expression products in E.coli and Streptomyces consistently produced a compound with identical retention time and[M+]of m/z 204.Subsequent isolation,purification,and NMR analysis confirmed this compound as calarene.[Conclusion]The FPP cyclase encoded by orf2064 in S.exfoliatus is identified as an calarene synthase.
文摘Objective:To investigate the mechanism of anticancer activity of a pigment OR3 from Streptomyces coelicolor in in vitro and in vivo metastatic breast cancer models and to characterize the pigment.Methods:The anticancer mechanism was analyzed in MDA-MB-231 cells using MTT,lactate dehydrogenase,caspase,DNA fragmentation,clonogenic,flow cytometry,Western blot,and scratch assays.The effects of OR3 on xenograft mouse models were evaluated by tumor volume measurement,hematological analysis,and histopathological observation.The characterization of OR3 was also performed using gas chromatograohy-mass spectrometry and nuclear magnetic resonance spectroscopy.Results:OR3 exhibited potent cytotoxicity against MDA-MB-231 cells,with no observed effects on HEK-293 cells.Caspase-9 activation was detected in OR3-treated MDA-MB-231 cells.Flow cytometry showed a dose-dependent induction of apoptosis and cell cycle arrest at the sub-G_(1) and S phases.Furthermore,OR3 completely inhibited MDA-MB-231 cell migration and demonstrated anti-proliferative effects by downregulating the protein expression of KPNA2,XPO1,RAB5B,and p38 MAPK.In in vivo studies,OR3 was non-toxic to mice,inhibited tumor xenograft growth,and maintained normal hematological parameters and tissue architecture.Nuclear magnetic resonance spectroscopy demonstrated the presence of a prodigiosin-like compound,while gas chromatography-mass spectrometry analysis identified additional compounds in OR3.Conclusions:Our findings validate OR3 pigment as a promising compound for the treatment of metastatic breast cancer,warranting further studies.
基金funded by the Agricultural Science and Technology Innovation Fund of Jiangsu Province[Grant/Award Number:CX(24)1008]Key Research and Development Program Project of Henan Province(251111110100)National State Science Foundation of China[Grant/Award Number:21808093].
文摘Long-time fermentation has always been one of the reasons restricting the development of straw biological pulping.This study aimed to develop a novel straw pulp film with shortened solid-state fermentation time with less than 20%mass loss rate by bio-pulping synergistic treatment of straw fibers with deep eutectic solvent(DES)and Streptomyces rochei(S.rochei).Results illustrated that at 3%S.rochei concentration with 7-day fermentation,both cellulose and hemicellulose enzyme activities of the treated rice straw fiber reached peak values with a fiber mass loss rate of 17.01%.Microstructural morphology revealed that S.rochei colonization initiated on straw surfaces and progressively penetrated internal structures,resulting in surface loosening and distinct disruption of cell wall tissues within vascular bundles in transverse sections.The treated rice straw strip indicated a maximum tensile strength of 46.22 MPa for(Bacteria)BA 3%at day 7,attributed to optimized synergistic effects of microfibril angle(MFA)and cellulose/hemicellulose relative content ratio.The modified straw pulp film exhibited significant enhancement in the tensile index(44.9%increase),burst index(10.3%increase),and tear index(60%increase)compared to untreated groups.This work demonstrated the important role ofDES and S.rochei bio-pulping synergistic treatment in improving rice straw pulp performance,suggesting an eco-friendly,novel,and efficient biomass pretreatment technology for potential application prospects in sustainable agricultural mulching materials.
基金the Program for the National Key R&D Program of China(2022YFD1700204)the National Natural Science Foundation(32272580).
文摘In the world of microorganisms,the genud Streptomyces is renowned as a"natural pharmacy".This genus of bacteria is the primary source of clinical antibiotics,with approximately two-thirds of antibiotics derived from it.However,industrial production faces challenges such as low yields and complex regulation.This study introduces the Streptomyces multiplexed artificial control system(SMARTS):a novel"plug-and-play"dynamic regulatory framework integrating trigger,stabilizer,and multiplexer modules.This enables the cross-species,predictable,and scalable production of secondary metabolites.Evolutionary analysis of 521 quorum-sensing receptors revealed conserved DNA-binding domains,informing the design of a universal trigger.SMARTS efficiently and robustly produced baiweimycin in a 120 m3 industrial fermenter,a process validated through a closed-loop pipeline ranging from molecular mechanisms to field applications.Implementing orthogonal control and hierarchical optimization enhances the efficiency of metabolic engineering and sheds light on the evolution of Streptomyces quorum sensing.This breakthrough offers a scalable solution for industrial production and advances synthetic biology,with significant implications for agriculture,pharmaceuticals,and global health.
基金Supported by Basic Research Fund for Central Nonprofit Institutes(Agro-environmental Protection Institute of Ministry of Agriculture)~~
文摘[Objective] The research aimed to screen Streptomyces hygroscopicus strains with high production of agricultural antibiotics. [ Method] A strain of S. hygroscopicus was screened from the soil of Hainan Island. After natural screening and consecutive ultraviolet induced mutation twice, S6-7 strain was obtained as the original strain then treated by UV irradiation and streptomycin resistance screening, and finally rescreened through shake-flask fermentation. [Result] 7 better strains were selected by primary screening from 62 single colonies which were picked out randomly. After 3 generations of consecutive cultivation on slant media and rescreening, 5 strains presented obvious forward mutation. The forward mutation rate reached 8.06%, and the largest production increasing rate came up to 25.11%. [Conclusion] By combining streptomycin resistance screening and conventional ultraviolet induced mutation, both the antibiotic-producing capacity and forward mutation screening efficiency of the original strain were greatly enhanced.
