Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections.Herein,we developed a close-packed and ordered Au@AgPt array coupled with a cas...Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections.Herein,we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering(SERS)and colorimetric identification of the Staphylococcus aureus biomarker micrococcal nuclease(MNase)in serum samples.The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine(TMB)molecules to SERS-enhanced oxidized TMB(oxTMB),accompanied by the color change from colorless to blue.In the presence of S.aureus,the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads(MBs)to release alkaline phosphatase(ALP),which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away.Using this“on-to-off”triggering strategy,the target S.aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode.Meanwhile,the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis(n=7)and healthy participants(n=3),as well as monitored the prognostic progression of the disease(n=2).Overall,benefiting from highly active and dense“hot spot”substrate,MNase-mediated cascade response strategy,and colorimetric/SERS dual-signal output,this methodology will offer a promising avenue for the early diagnosis of S.aureus infection.展开更多
Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.I...Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.:82373833,22177039,and 82304438)the National Key Research and Development Program of China(Grant No.:2021YFC2300400)Guangdong Basic and Applied Basic Research Foundation,China(Grant Nos.:2024A1515012204,2022A1515010300,and 2022A1515110618).
文摘Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections.Herein,we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering(SERS)and colorimetric identification of the Staphylococcus aureus biomarker micrococcal nuclease(MNase)in serum samples.The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine(TMB)molecules to SERS-enhanced oxidized TMB(oxTMB),accompanied by the color change from colorless to blue.In the presence of S.aureus,the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads(MBs)to release alkaline phosphatase(ALP),which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away.Using this“on-to-off”triggering strategy,the target S.aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode.Meanwhile,the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis(n=7)and healthy participants(n=3),as well as monitored the prognostic progression of the disease(n=2).Overall,benefiting from highly active and dense“hot spot”substrate,MNase-mediated cascade response strategy,and colorimetric/SERS dual-signal output,this methodology will offer a promising avenue for the early diagnosis of S.aureus infection.
基金financially supported by the National Key Agriculture Projects(NK2022060101)National Key Research and Development Program(2022YFF1002900,2020YFE0202900)+3 种基金the Fundamental Research Funds for the Central University(XUEKEN2022012)Jiangsu Provincial Key Research and Development Program(BE2021375,BE2022346)Seed Industry Revitalization Project of Jiangsu Province(JBGS2021006,2021013,2021047)Joint Research of Improved Wheat Variety of Anhui,and Jiangsu Agricultural Technology System(JATS)(JATS[2021]463,JATS[2022]464).
文摘Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.
