Endophytic fungi are promising producers of bioactive small molecules.Bioinformatic analysis of the genome of an endophytic fungus Penicillium dangeardii revealed 43 biosynthetic gene clusters,exhibited its strong abi...Endophytic fungi are promising producers of bioactive small molecules.Bioinformatic analysis of the genome of an endophytic fungus Penicillium dangeardii revealed 43 biosynthetic gene clusters,exhibited its strong ability to produce numbers of secondary metabolites.However,this strain mainly produce rubratoxins alone with high yield in varied culture conditions,suggested most gene clusters are silent.Efforts for mining the cryptic gene clusters in P.dangeardii,including epigenetic regulation and one-strain-many-compounds(OSMAC)approach were failed probably due to the high yield of rubratoxins.A metabolic shunting strategy by deleting the key gene for rubratoxins biosynthesis combining with optimization of culture condition successfully activated multiple silent genes encoding for other polyketide synthases(PKSs),and led to the trace compounds detectable.As a result,a total of 23 new compounds including azaphilone monomers,dimers,turimers with unprecedented polycyclic bridged heterocycle and spiral structures,as well as siderophores were identified.Some compounds showed significant cytotoxicities,anti-inflammatory or antioxidant activities.The attractive dual PKS s gene clusters for azaphilones biosynthesis were mined by bioinformatic analysis and overexpression of a pathway specific transcription factor.Our work therefor provides an efficient approach to mine the chemical diversity of endophytic fungi.展开更多
Epigenetic modifications have been proved to be a powerful way to activate silent gene clusters and lead to diverse secondary metabolites in fungi. Previously, inactivation of a histone H3 deacetylase in Calcarisporiu...Epigenetic modifications have been proved to be a powerful way to activate silent gene clusters and lead to diverse secondary metabolites in fungi. Previously, inactivation of a histone H3 deacetylase in Calcarisporium arbuscula had led to pleiotropic activation and overexpression of more than 75% of the biosynthetic genes and isolation of ten compounds. Further investigation of the crude extract of C. arbuscula Δhda A strain resulted in the isolation of twelve new diterpenoids including three cassanes(1-3), one cleistanthane(4), six pimaranes(5-10), and two isopimaranes(11 and 12) along with two know cleistanthane analogues. Their structures were elucidated by extensive NMR spectroscopic data analysis. Compounds 2 and 4 showed potent inhibitory effects on the expression of MMP1 and MMP2(matrix metalloproteinases family) in human breast cancer(MCF-7) cells.展开更多
Fungal genomes carry many gene clusters seemingly capable of natural products biosynthesis,yet most clusters remain cryptic or down-regulated. Genome mining revealed an unconventional paraherquonin-like meroterpenoid ...Fungal genomes carry many gene clusters seemingly capable of natural products biosynthesis,yet most clusters remain cryptic or down-regulated. Genome mining revealed an unconventional paraherquonin-like meroterpenoid biosynthetic gene cluster in the chromosome of Neosartorya glabra.The cryptic or down-regulated pathway was activated by constitutive expression of pathway-specific regulator gene ber A encoded within ber biosynthetic gene cluster. Chemical analysis of mutant Ng-OE:ber A extracts enabled the isolation of four berkeleyacetal congeners, in which two of them are new. On the basis of careful bioinformatic analysis of the coding enzymes in the ber gene cluster, the biosynthetic pathway of berkeleyacetals was proposed. These results indicate that this approach would be valuable for discovery of novel natural products and will accelerate the exploitation of prodigious natural products in filamentous fungi.展开更多
Investigation on how nature produces natural compounds with chemical and biological diversity at the genetic level offers inspiration for the discovery of new natural products and even their biological targets.The pol...Investigation on how nature produces natural compounds with chemical and biological diversity at the genetic level offers inspiration for the discovery of new natural products and even their biological targets.The polyketide rumbrin(1)is a lipid peroxide production and calcium accumulation inhibitor,which contains a chlorinated pyrrole moiety that is a rare chemical feature in fungal natural products.Here,we identify the biosynthetic gene cluster(BGC)rum of 1 and its isomer 12E-rumbrin(2)from Auxarthron umbrinum DSM3193,and elucidate their biosynthetic pathway based on heterolo-gous expression,chemical complementation,and isotopic labeling.We show that rumbrins are assembled by a highly reducing polyketide synthase(HRPKS)that uniquely incorporates a proline-derived pyrrolyl-CoA starer unit,and followed by methylation and chlorination.Sequent precursor directed biosynthesis was able to yield a group of rumbrin analogues.Remarkably,inspired by the presence of a human immunodeficiency virus(HIV)-Nef associated gene in the rum cluster,we predicted and pharmacologically demonstrated rumbrins as potent inhibitors of HIV at the nanomolar level.This work enriches the recognition of unconventional starter units of fungal PKSs and provides a new strategy for genome mining-guided drug discovery.展开更多
基金supported financially by the National Key Research and Development Program of China(2018YFA0901900)the CAMS Innovation Fund for Medical Sciences(CIFMS,2016-I2M-1-010,2017-I2M-4-004)+1 种基金Fundamental Research Funds for the Central Universities(2017PT35001)supported by the Drug Innovation Major Project(2018ZX09711001-008-001)
文摘Endophytic fungi are promising producers of bioactive small molecules.Bioinformatic analysis of the genome of an endophytic fungus Penicillium dangeardii revealed 43 biosynthetic gene clusters,exhibited its strong ability to produce numbers of secondary metabolites.However,this strain mainly produce rubratoxins alone with high yield in varied culture conditions,suggested most gene clusters are silent.Efforts for mining the cryptic gene clusters in P.dangeardii,including epigenetic regulation and one-strain-many-compounds(OSMAC)approach were failed probably due to the high yield of rubratoxins.A metabolic shunting strategy by deleting the key gene for rubratoxins biosynthesis combining with optimization of culture condition successfully activated multiple silent genes encoding for other polyketide synthases(PKSs),and led to the trace compounds detectable.As a result,a total of 23 new compounds including azaphilone monomers,dimers,turimers with unprecedented polycyclic bridged heterocycle and spiral structures,as well as siderophores were identified.Some compounds showed significant cytotoxicities,anti-inflammatory or antioxidant activities.The attractive dual PKS s gene clusters for azaphilones biosynthesis were mined by bioinformatic analysis and overexpression of a pathway specific transcription factor.Our work therefor provides an efficient approach to mine the chemical diversity of endophytic fungi.
基金supported financially by National Natural Science Foundation of China (Nos. 21502233 and 81522043)CAMS Initiative for Innovative Medicine (CAMS-I2M-1-010)+1 种基金the PUMC Youth Fund (33320140175)the State Key Laboratory Fund for Excellent Young Scientists to Youcai Hu (GTZB201401)
文摘Epigenetic modifications have been proved to be a powerful way to activate silent gene clusters and lead to diverse secondary metabolites in fungi. Previously, inactivation of a histone H3 deacetylase in Calcarisporium arbuscula had led to pleiotropic activation and overexpression of more than 75% of the biosynthetic genes and isolation of ten compounds. Further investigation of the crude extract of C. arbuscula Δhda A strain resulted in the isolation of twelve new diterpenoids including three cassanes(1-3), one cleistanthane(4), six pimaranes(5-10), and two isopimaranes(11 and 12) along with two know cleistanthane analogues. Their structures were elucidated by extensive NMR spectroscopic data analysis. Compounds 2 and 4 showed potent inhibitory effects on the expression of MMP1 and MMP2(matrix metalloproteinases family) in human breast cancer(MCF-7) cells.
基金supported financially by the National Natural Science Foundation of China (No. 81522043)CAMS Initiative for Innovative Medicine (2017-I2M-4-004)the Thousand Young Talents Program of China
文摘Fungal genomes carry many gene clusters seemingly capable of natural products biosynthesis,yet most clusters remain cryptic or down-regulated. Genome mining revealed an unconventional paraherquonin-like meroterpenoid biosynthetic gene cluster in the chromosome of Neosartorya glabra.The cryptic or down-regulated pathway was activated by constitutive expression of pathway-specific regulator gene ber A encoded within ber biosynthetic gene cluster. Chemical analysis of mutant Ng-OE:ber A extracts enabled the isolation of four berkeleyacetal congeners, in which two of them are new. On the basis of careful bioinformatic analysis of the coding enzymes in the ber gene cluster, the biosynthetic pathway of berkeleyacetals was proposed. These results indicate that this approach would be valuable for discovery of novel natural products and will accelerate the exploitation of prodigious natural products in filamentous fungi.
基金supported financially by the National Key Research and Development Program of China(2018YFA0901900)the CAMS Innovation Fund for Medical Sciences (CIFMS, No. 2021-I2M-1-029, China)
文摘Investigation on how nature produces natural compounds with chemical and biological diversity at the genetic level offers inspiration for the discovery of new natural products and even their biological targets.The polyketide rumbrin(1)is a lipid peroxide production and calcium accumulation inhibitor,which contains a chlorinated pyrrole moiety that is a rare chemical feature in fungal natural products.Here,we identify the biosynthetic gene cluster(BGC)rum of 1 and its isomer 12E-rumbrin(2)from Auxarthron umbrinum DSM3193,and elucidate their biosynthetic pathway based on heterolo-gous expression,chemical complementation,and isotopic labeling.We show that rumbrins are assembled by a highly reducing polyketide synthase(HRPKS)that uniquely incorporates a proline-derived pyrrolyl-CoA starer unit,and followed by methylation and chlorination.Sequent precursor directed biosynthesis was able to yield a group of rumbrin analogues.Remarkably,inspired by the presence of a human immunodeficiency virus(HIV)-Nef associated gene in the rum cluster,we predicted and pharmacologically demonstrated rumbrins as potent inhibitors of HIV at the nanomolar level.This work enriches the recognition of unconventional starter units of fungal PKSs and provides a new strategy for genome mining-guided drug discovery.