Keystone taxa are critical for microbial community homeostasis and ecological niche interactions.However,the functions and genomic traits of endophytic keystone fungi in plant tissues remain unclear.Via network analys...Keystone taxa are critical for microbial community homeostasis and ecological niche interactions.However,the functions and genomic traits of endophytic keystone fungi in plant tissues remain unclear.Via network analysis,this study identified keystone fungi Plectosphaerella(Plec)and Cladosporium(Clad)in roots/leaves of medicinal Panax plants(P.ginseng,P.quinquefolius,P.notoginseng).Both correlated strongly positively with ginsenoside Rd content in respective tissues(ρ>0.6,p<0.001).Co-cultivation confirmed their ability to convert ginsenoside Rb1 to Rd,linked toβ-glucosidase activity.Whole-genome sequencing/assembly/evolutionary analysis of the two strains elucidated genomic features for their keystone roles and saponin biotransformation.Genome mining found multiple GH3 genes(potential saponin transformers)in both;11(Plec)and 5(Clad)were upregulated by cellobiose.Gene family phylogenetic analysis showed expanded transmembrane transport and environmental response functions.Both also had abundant secondary metabolic gene clusters and secretome genes,linking biotic interaction functions to their keystone roles.In summary,this study shows Panax endophytic keystone fungi can participate in ginsenoside biotransformation and clarifies their genomic traits,offering insights for functional endophytic fungal resource development.展开更多
phoD and pqqC gene occurrence in bacteria allows them to mobilize phosphorus(P)by mineralizing organic P(Po)and solubilizing inorganic P(Pi),respectively.Community characteristics of phoD-and pqqC-harboring bacteria(p...phoD and pqqC gene occurrence in bacteria allows them to mobilize phosphorus(P)by mineralizing organic P(Po)and solubilizing inorganic P(Pi),respectively.Community characteristics of phoD-and pqqC-harboring bacteria(phoD-and pqqC-HB,respectively)mediate P cycling.However,whether the microbial community assembly and keystone taxa of phoD-and pqqC-HB regulate P availability and distinct regulatory pathways between these two genes remain unclear.In this study,soil microbial community characteristics and P availability were investigated in four long-term(38-year)fertilization regimes:control with no fertilizer(CK),P fertilizer(PF),nitrogen(N)and P fertilizers(NP),and N fertilizer,P fertilizer,and manure(NPM).The N addition treatments(NP and NPM)significantly changed the community composition and increased the abundances of phoD-and pqqC-HB compared to the no-N addition treatments(CK and PF).Stochastic processes dominated the community assembly of both phoD-and pqqC-HB,and the relative contributions of stochasticity increased with N addition.Furthermore,the N addition treatments resulted in greater network complexity and higher abundances of keystone taxa of phoD-and pqqC-HB compared to those of the no-N addition treatments.The keystone taxa implicated in P cycling were also associated with carbon(C)and N cycling processes.Microbial community composition and assembly processes were the main factors driving labile Pi for phoD-HB,whereas keystone taxa contributed the most to labile Pi for pqqC-HB.These results emphasize that distinct mechanisms of phoD-and pqqC-HB regulate P availability under fertilization management and underline the significance of microbial community assembly and keystone taxa in soil ecological functions,offering fresh perspectives on comprehending the biological processes facilitated by microorganisms in enhancing soil quality.展开更多
基于Keystone变换技术研究正交频分复用(Orthogonal frequency division multiplexing,OFDM)雷达信号距离单元走动校正方法。在研究OFDM雷达信号数学原理的基础上,本文给出了理想点目标的脉冲串回波信号表达式。针对发射信号内在结构特...基于Keystone变换技术研究正交频分复用(Orthogonal frequency division multiplexing,OFDM)雷达信号距离单元走动校正方法。在研究OFDM雷达信号数学原理的基础上,本文给出了理想点目标的脉冲串回波信号表达式。针对发射信号内在结构特性,分析了相对运动对目标回波信号的影响。推导了脉冲体制OFDM回波信号的距离频率域模型,讨论了基于Keystone变换的距离走动校正技术。最后给出典型系统参数下的仿真实验结果,验证了方法的有效性。展开更多
基金funded by the National Natural Science Foundation of China(82274044,82304663)National Key Research and Development Program(2022YFC3501802,2022YFC3501803,and 2022YFC3501804)+1 种基金the Scientific and technological innovation project of China Academy of Chinese Medical Sciences(CI2023E002,CI2024E003)the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ13-YQ-049,ZZ16-XRZ-072,ZZ17-YQ-025,ZXKT22052,and ZXKT22060).
文摘Keystone taxa are critical for microbial community homeostasis and ecological niche interactions.However,the functions and genomic traits of endophytic keystone fungi in plant tissues remain unclear.Via network analysis,this study identified keystone fungi Plectosphaerella(Plec)and Cladosporium(Clad)in roots/leaves of medicinal Panax plants(P.ginseng,P.quinquefolius,P.notoginseng).Both correlated strongly positively with ginsenoside Rd content in respective tissues(ρ>0.6,p<0.001).Co-cultivation confirmed their ability to convert ginsenoside Rb1 to Rd,linked toβ-glucosidase activity.Whole-genome sequencing/assembly/evolutionary analysis of the two strains elucidated genomic features for their keystone roles and saponin biotransformation.Genome mining found multiple GH3 genes(potential saponin transformers)in both;11(Plec)and 5(Clad)were upregulated by cellobiose.Gene family phylogenetic analysis showed expanded transmembrane transport and environmental response functions.Both also had abundant secondary metabolic gene clusters and secretome genes,linking biotic interaction functions to their keystone roles.In summary,this study shows Panax endophytic keystone fungi can participate in ginsenoside biotransformation and clarifies their genomic traits,offering insights for functional endophytic fungal resource development.
基金supported by the National Key Research and Development Program of China(No.2022YFD 1901601)the National Natural Science Foundation of China(No.42107360)the Fundamental Research Funds for the Central Universities,China(No.2452021032).
文摘phoD and pqqC gene occurrence in bacteria allows them to mobilize phosphorus(P)by mineralizing organic P(Po)and solubilizing inorganic P(Pi),respectively.Community characteristics of phoD-and pqqC-harboring bacteria(phoD-and pqqC-HB,respectively)mediate P cycling.However,whether the microbial community assembly and keystone taxa of phoD-and pqqC-HB regulate P availability and distinct regulatory pathways between these two genes remain unclear.In this study,soil microbial community characteristics and P availability were investigated in four long-term(38-year)fertilization regimes:control with no fertilizer(CK),P fertilizer(PF),nitrogen(N)and P fertilizers(NP),and N fertilizer,P fertilizer,and manure(NPM).The N addition treatments(NP and NPM)significantly changed the community composition and increased the abundances of phoD-and pqqC-HB compared to the no-N addition treatments(CK and PF).Stochastic processes dominated the community assembly of both phoD-and pqqC-HB,and the relative contributions of stochasticity increased with N addition.Furthermore,the N addition treatments resulted in greater network complexity and higher abundances of keystone taxa of phoD-and pqqC-HB compared to those of the no-N addition treatments.The keystone taxa implicated in P cycling were also associated with carbon(C)and N cycling processes.Microbial community composition and assembly processes were the main factors driving labile Pi for phoD-HB,whereas keystone taxa contributed the most to labile Pi for pqqC-HB.These results emphasize that distinct mechanisms of phoD-and pqqC-HB regulate P availability under fertilization management and underline the significance of microbial community assembly and keystone taxa in soil ecological functions,offering fresh perspectives on comprehending the biological processes facilitated by microorganisms in enhancing soil quality.
文摘基于Keystone变换技术研究正交频分复用(Orthogonal frequency division multiplexing,OFDM)雷达信号距离单元走动校正方法。在研究OFDM雷达信号数学原理的基础上,本文给出了理想点目标的脉冲串回波信号表达式。针对发射信号内在结构特性,分析了相对运动对目标回波信号的影响。推导了脉冲体制OFDM回波信号的距离频率域模型,讨论了基于Keystone变换的距离走动校正技术。最后给出典型系统参数下的仿真实验结果,验证了方法的有效性。
