Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds,due to their fancy strategies for adaptation and being under-investigated.Two new phenazine alkaloids(1 and 2)and one new phenoxa-z...Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds,due to their fancy strategies for adaptation and being under-investigated.Two new phenazine alkaloids(1 and 2)and one new phenoxa-zine(3)were isolated from Nocardiopsis dassonvillei 502F,a strain originally isolated from Arctic deep-sea sediments.AntiSMASH analysis of the genome of Nocardiopsis dassonvillei 502F revealed the presence of 16 putative biosynthetic gene clusters(BGCs),including a phenazine BGC.Most of the isolated compounds were evaluated for their antibacterial,antiallergic,and cytotoxic activities.Among them,compounds 4 and 5 exhibited potent in vitro cytotoxic activities against osteosarcoma cell line 143B with IC_(50) values 0.16 and 20.0μM,respectively.Besides,the results of antiallergic activities of compounds 6-8 exhibited inhibitory activities with IC_(50) values of 10.88±3.05,38.88±3.29,and 2.44±0.17μg/mL,respectively(IC_(50)91.6μM for the positive control loratadine).展开更多
Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,thre...Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,three new angucyclines,nocardiopsistins A-C,were isolated from Nocardiopsis sp.strain HB-J378.Notably,the supplementation of the rare earth salt Lanthanum chloride(LaCl3)during fermentation of HB-J378 significantly increased the yield of these angucyclines.The structures of nocardiopsistins A-C were identified by 1D and 2D NMR and HR-MS data.Nocardiopsistins A-C have activity against MRSA(methicillin-resistant Staphylococcus aureus)with MICs of 3.12–12.5μg/mL;the potency of nocardiopsistin B is similar to that of the positive control,chloramphenicol.Bioinformatic analysis of the draft genome of HB-J378 identified a set of three core genes in a biosynthetic gene cluster that encode a typical aromatic or type II polyketide synthase(PKS)system,including ketoacyl:ACP synthaseα-subunit(KSα),β-subunit(KSβ)and acyl carrier protein(ACP).The production of nocardiopsistins A-C was abolished when the three genes were knocked out,indicating their indispensable role in the production of nocardiopsistins.展开更多
The biosynthetic potential of actinobacteria to produce novel natural products is still regarded as immense.In this paper,we correlated a cryptic biosynthetic gene cluster to chemical molecules by genome mining and ch...The biosynthetic potential of actinobacteria to produce novel natural products is still regarded as immense.In this paper,we correlated a cryptic biosynthetic gene cluster to chemical molecules by genome mining and chemical analyses,leading to the discovery of a new group of catecholate-hydroxamate siderophores,nobachelins,from Nocardiopsis baichengensis DSM 44845.Nobachelin biosynthesis genes are conserved in several bacteria from the family Nocardiopsidaceae.Structurally,nobachelins feature fatty-acylated hydroxy-ornithine and a rare chlorinated catecholate group.Intriguingly,nobachelins rescued Caenorhabditis elegans from Pseudomonas aeruginosa-mediated killing.展开更多
Objective:To reveal the screening of metal tolerance and dye-decolorizing of Nocardiopsis sp.Methods:NiSO_(4) and Congo red dye were used for evaluating the metal tolerance and dyedecolorizing of the randomly selected...Objective:To reveal the screening of metal tolerance and dye-decolorizing of Nocardiopsis sp.Methods:NiSO_(4) and Congo red dye were used for evaluating the metal tolerance and dyedecolorizing of the randomly selected actinobacterial isolates.Results:Nocardiopsis sp.SD8 showed a better efficiency in Ni(II)tolerance,though a longer lag phase was observed for this microorganism grown for 7 days in integrated mismatch negativity.Interestingly,we also found that Nocardiopsis sp.SD8 had dye-decolorizing,hemolytic,lipase and protease activity.Conclusions:The present results revealed the bioremediation of metal resistant and diverse properties of Nocardiopsis sp.SD8 and further investigations are needed to extract and identify the potent molecule.展开更多
In this study, 16 marine sponge samples collected from Eastern Mediterranean Sea were used for the isolation of sponge-associated Actinobacteria. Different media and pre-treatment methods were applied for the isolatio...In this study, 16 marine sponge samples collected from Eastern Mediterranean Sea were used for the isolation of sponge-associated Actinobacteria. Different media and pre-treatment methods were applied for the isolation experiments. In total, 7578 actinomycetes colonies were observed on the primary isolation plates, and 20 representative isolates were selected for further studies based on their morphologies and chemical profiles. These isolates were investigated for their antimicrobial activities, seawater requirements and 16S rRNA gene sequences. The phylogenetic analysis revealed that 80% of the isolated Actinobacteria was a member of the Streptomyces genus. All the isolates showed no absolute requirement for seawater. Fifteen of the selected isolates exhibited antimicrobial activity against methicillin resistant Staphylococcus aureus and vancomycin resistant Enterococcus faecium, whereas 3 isolates were active against Candida albicans.展开更多
基金the Guangdong Basic and Applied Basic Research Foundation(2021A1515011523,2021B1515120046,2022B1515120075)National Key Research and Development Program of China(2022YFC2807501)+2 种基金National Natural Science Foundation of China(grant no.41976224)Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City(2021JJLH0097,2021CXLH0013)Hainan Provincial Natural Science Foundation of China(823CXTD393)。
文摘Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds,due to their fancy strategies for adaptation and being under-investigated.Two new phenazine alkaloids(1 and 2)and one new phenoxa-zine(3)were isolated from Nocardiopsis dassonvillei 502F,a strain originally isolated from Arctic deep-sea sediments.AntiSMASH analysis of the genome of Nocardiopsis dassonvillei 502F revealed the presence of 16 putative biosynthetic gene clusters(BGCs),including a phenazine BGC.Most of the isolated compounds were evaluated for their antibacterial,antiallergic,and cytotoxic activities.Among them,compounds 4 and 5 exhibited potent in vitro cytotoxic activities against osteosarcoma cell line 143B with IC_(50) values 0.16 and 20.0μM,respectively.Besides,the results of antiallergic activities of compounds 6-8 exhibited inhibitory activities with IC_(50) values of 10.88±3.05,38.88±3.29,and 2.44±0.17μg/mL,respectively(IC_(50)91.6μM for the positive control loratadine).
基金This work was supported in part by the NIH grant CA209189.
文摘Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,three new angucyclines,nocardiopsistins A-C,were isolated from Nocardiopsis sp.strain HB-J378.Notably,the supplementation of the rare earth salt Lanthanum chloride(LaCl3)during fermentation of HB-J378 significantly increased the yield of these angucyclines.The structures of nocardiopsistins A-C were identified by 1D and 2D NMR and HR-MS data.Nocardiopsistins A-C have activity against MRSA(methicillin-resistant Staphylococcus aureus)with MICs of 3.12–12.5μg/mL;the potency of nocardiopsistin B is similar to that of the positive control,chloramphenicol.Bioinformatic analysis of the draft genome of HB-J378 identified a set of three core genes in a biosynthetic gene cluster that encode a typical aromatic or type II polyketide synthase(PKS)system,including ketoacyl:ACP synthaseα-subunit(KSα),β-subunit(KSβ)and acyl carrier protein(ACP).The production of nocardiopsistins A-C was abolished when the three genes were knocked out,indicating their indispensable role in the production of nocardiopsistins.
基金support from the Helmholtz International Lab(InterLabs0007)Yuhao Ren acknowledges the support from the International Postdoctoral Exchange Fellowship Program(ZD202125)between Helmholtz AssociationGermany and the Office of China Postdoc Council(OCPC),China.
文摘The biosynthetic potential of actinobacteria to produce novel natural products is still regarded as immense.In this paper,we correlated a cryptic biosynthetic gene cluster to chemical molecules by genome mining and chemical analyses,leading to the discovery of a new group of catecholate-hydroxamate siderophores,nobachelins,from Nocardiopsis baichengensis DSM 44845.Nobachelin biosynthesis genes are conserved in several bacteria from the family Nocardiopsidaceae.Structurally,nobachelins feature fatty-acylated hydroxy-ornithine and a rare chlorinated catecholate group.Intriguingly,nobachelins rescued Caenorhabditis elegans from Pseudomonas aeruginosa-mediated killing.
基金Supported by DST(Ref No.DST/IS-STAC/CO2-SR-163/13(G)).
文摘Objective:To reveal the screening of metal tolerance and dye-decolorizing of Nocardiopsis sp.Methods:NiSO_(4) and Congo red dye were used for evaluating the metal tolerance and dyedecolorizing of the randomly selected actinobacterial isolates.Results:Nocardiopsis sp.SD8 showed a better efficiency in Ni(II)tolerance,though a longer lag phase was observed for this microorganism grown for 7 days in integrated mismatch negativity.Interestingly,we also found that Nocardiopsis sp.SD8 had dye-decolorizing,hemolytic,lipase and protease activity.Conclusions:The present results revealed the bioremediation of metal resistant and diverse properties of Nocardiopsis sp.SD8 and further investigations are needed to extract and identify the potent molecule.
基金supported by Scientific and Technological Research Council of Turkey(TUBİTAK)with SBAG-109S361project number.
文摘In this study, 16 marine sponge samples collected from Eastern Mediterranean Sea were used for the isolation of sponge-associated Actinobacteria. Different media and pre-treatment methods were applied for the isolation experiments. In total, 7578 actinomycetes colonies were observed on the primary isolation plates, and 20 representative isolates were selected for further studies based on their morphologies and chemical profiles. These isolates were investigated for their antimicrobial activities, seawater requirements and 16S rRNA gene sequences. The phylogenetic analysis revealed that 80% of the isolated Actinobacteria was a member of the Streptomyces genus. All the isolates showed no absolute requirement for seawater. Fifteen of the selected isolates exhibited antimicrobial activity against methicillin resistant Staphylococcus aureus and vancomycin resistant Enterococcus faecium, whereas 3 isolates were active against Candida albicans.
