Small non-protein coding micro-RNAs are regularly exported out of cells, both in health and disease. More than ninety percent of extracellular miRNAs are associated with lower-molecular-mass complexes bound to Argonau...Small non-protein coding micro-RNAs are regularly exported out of cells, both in health and disease. More than ninety percent of extracellular miRNAs are associated with lower-molecular-mass complexes bound to Argonaute 2 (Ago2), nucleophosmin-1 (NPM1) and high density lipoproteins (HDL), whereas the rest (~10%) are membrane-vesicle-encapsulated within exosomes, shedding microvesicles and apoptotic bodies. Regardless of the debate of the nature of circulating miRNA as byproducts of routine cell activities or mediators of cell-cell communication, proper understanding of the molecular behaviors of miRNA in health and disease, is expected to open a new gate for the discovery of new diagnostic tools and possibly therapeutic implementation in the near future.展开更多
Candidatus Accumulibacter,a prominent polyphosphate-accumulating organism(PAO)in wastewater treatment,plays a crucial role in enhanced biological phosphorus removal(EBPR).The genetic underpinnings of its polyphosphate...Candidatus Accumulibacter,a prominent polyphosphate-accumulating organism(PAO)in wastewater treatment,plays a crucial role in enhanced biological phosphorus removal(EBPR).The genetic underpinnings of its polyphosphate accumulation capabilities,however,remain largely unknown.Here,we conducted a comprehensive genomic analysis of Ca.Accumulibacter-PAOs and their relatives within the Rhodocyclaceae family,identifying 124 core genes acquired via horizontal gene transfer(HGT)at its least common ancestor.Metatranscriptomic analysis of an enrichment culture of Ca.Accumulibacter revealed active transcription of 44 of these genes during an EBPR cycle,notably including the polyphosphate kinase 2(PPK2)gene instead of the commonly recognized polyphosphate kinase 1(PPK1)gene.Intriguingly,the phosphate regulon(Pho)genes showed minimal transcriptions,pointing to a distinctive fact of Pho dysregulation,where PhoU,the phosphate signaling complex protein,was not regulating the high-affinity phosphate transport(Pst)system,resulting in continuous phosphate uptake.To prevent phosphate toxicity,Ca.Accumulibacter utilized the laterally acquired PPK2 to condense phosphate into polyphosphate,resulting in the polyphosphate-accumulating feature.This study provides novel insights into the evolutionary emergence of the polyphosphate-accumulating trait in Ca.Accumulibacter,offering potential advancements in understanding the PAO phenotype in the EBPR process.展开更多
The global increased antibiotic resistance level in pathogenic microbes has posed a significant threat to human health.Fresh vegetables have been recognized to be an important vehicle of antibiotic resistance genes(AR...The global increased antibiotic resistance level in pathogenic microbes has posed a significant threat to human health.Fresh vegetables have been recognized to be an important vehicle of antibiotic resistance genes(ARGs)from environments to human beings.Phyllosphere ARGs have been indicated to be changed with plant species,yet the influence of plant cultivar on the phyllospheric resistome is still unclear.Here,we detected the ARGs and bacterial communities in the phyllosphere of two cultivars of cilantros and their corresponding soils using high-throughput quantitative PCR technique and bacterial 16S rRNA gene-based high-throughput sequencing,respectively.We further identified the potential bacterial pathogens and analyzed the effects of plant cultivar on ARGs,mobile genetic elements(MGEs),microbiome and potential bacterial pathogens.The results showed that the cultivars did not affect the ARG abundance and composition,but significantly shaped the abundance of MGEs and the composition structure of bacteria in the phyllosphere.The relative abundance of potential bacterial pathogenswas significantly higher in the phyllosphere than that in soils.Mantel test showed that the ARG patterns were significantly correlated to the patterns of potential bacterial pathogens.Our results suggested that the horizontal gene transfer of ARGs in the phyllosphere might be different between the two cultivars of cilantro and highlighted the higher risk of phyllospheric microorganisms compared with those in soils.These findings extend our knowledge on the vegetable microbiomes,ARGs,and potential pathogens,suggesting more agricultural and hygiene protocols are needed to control the risk of foodborne ARGs.展开更多
文摘Small non-protein coding micro-RNAs are regularly exported out of cells, both in health and disease. More than ninety percent of extracellular miRNAs are associated with lower-molecular-mass complexes bound to Argonaute 2 (Ago2), nucleophosmin-1 (NPM1) and high density lipoproteins (HDL), whereas the rest (~10%) are membrane-vesicle-encapsulated within exosomes, shedding microvesicles and apoptotic bodies. Regardless of the debate of the nature of circulating miRNA as byproducts of routine cell activities or mediators of cell-cell communication, proper understanding of the molecular behaviors of miRNA in health and disease, is expected to open a new gate for the discovery of new diagnostic tools and possibly therapeutic implementation in the near future.
基金supported by the National Natural Science Foundation of China(52270035 and 51808297)the Natural Science Foundation of Guangdong Province(2021A1515010494)+1 种基金the Guangzhou Key Research and Development Program(2023B03J1334)the Pearl River Talent Recruitment Program(2019QN01L125).
文摘Candidatus Accumulibacter,a prominent polyphosphate-accumulating organism(PAO)in wastewater treatment,plays a crucial role in enhanced biological phosphorus removal(EBPR).The genetic underpinnings of its polyphosphate accumulation capabilities,however,remain largely unknown.Here,we conducted a comprehensive genomic analysis of Ca.Accumulibacter-PAOs and their relatives within the Rhodocyclaceae family,identifying 124 core genes acquired via horizontal gene transfer(HGT)at its least common ancestor.Metatranscriptomic analysis of an enrichment culture of Ca.Accumulibacter revealed active transcription of 44 of these genes during an EBPR cycle,notably including the polyphosphate kinase 2(PPK2)gene instead of the commonly recognized polyphosphate kinase 1(PPK1)gene.Intriguingly,the phosphate regulon(Pho)genes showed minimal transcriptions,pointing to a distinctive fact of Pho dysregulation,where PhoU,the phosphate signaling complex protein,was not regulating the high-affinity phosphate transport(Pst)system,resulting in continuous phosphate uptake.To prevent phosphate toxicity,Ca.Accumulibacter utilized the laterally acquired PPK2 to condense phosphate into polyphosphate,resulting in the polyphosphate-accumulating feature.This study provides novel insights into the evolutionary emergence of the polyphosphate-accumulating trait in Ca.Accumulibacter,offering potential advancements in understanding the PAO phenotype in the EBPR process.
基金supported by the National Key Research and Development Plan from Ministry of Science and Technology of the People’s Republic of China(No.2020YFC1806902)the Alliance of International Science Organizations(No.ANSO-PA-2020-18).
文摘The global increased antibiotic resistance level in pathogenic microbes has posed a significant threat to human health.Fresh vegetables have been recognized to be an important vehicle of antibiotic resistance genes(ARGs)from environments to human beings.Phyllosphere ARGs have been indicated to be changed with plant species,yet the influence of plant cultivar on the phyllospheric resistome is still unclear.Here,we detected the ARGs and bacterial communities in the phyllosphere of two cultivars of cilantros and their corresponding soils using high-throughput quantitative PCR technique and bacterial 16S rRNA gene-based high-throughput sequencing,respectively.We further identified the potential bacterial pathogens and analyzed the effects of plant cultivar on ARGs,mobile genetic elements(MGEs),microbiome and potential bacterial pathogens.The results showed that the cultivars did not affect the ARG abundance and composition,but significantly shaped the abundance of MGEs and the composition structure of bacteria in the phyllosphere.The relative abundance of potential bacterial pathogenswas significantly higher in the phyllosphere than that in soils.Mantel test showed that the ARG patterns were significantly correlated to the patterns of potential bacterial pathogens.Our results suggested that the horizontal gene transfer of ARGs in the phyllosphere might be different between the two cultivars of cilantro and highlighted the higher risk of phyllospheric microorganisms compared with those in soils.These findings extend our knowledge on the vegetable microbiomes,ARGs,and potential pathogens,suggesting more agricultural and hygiene protocols are needed to control the risk of foodborne ARGs.
文摘油菜菌核病(Sclerotinia sclerotiorum)是油菜生产上最重要的病害之一,其致病性可能来源于基因水平转移(Horizontal gene transfer,HGT).为认识其致病原理和寻找新的真菌抑制剂的靶点,首先通过BLASTp发现其基因XM_001585458.1编码蛋白XP_001585508.1与细菌比对结果中出现低E值3.23e-109和高SCORE值436,暗示存在HGT现象;进一步通过系统进化树的建立,发现该蛋白在进化分枝上更接近于细菌中由Streptomyces sp.C的NZ_CM000832.1基因编码的蛋白ZP_07291173;同时核苷酸组成分析也发现该基因与油菜菌核病菌基因组的碱基组成有较大差别,GC含量提高了14.95%.这些结果证明了XM_001585458.1的确存在基因水平转移事件.结构分析和COG蛋白功能分类显示该HGT序列编码蛋白XP_001585508.1具有FA58C_3(Coagulation factors 5/8 type C domain)、Kelch repeat type 1、Galactose-binding domain-like、Galactose oxidase/kelch,beta-propeller等保守结构域,应为一个膜蛋白并参与多糖代谢,推测该水平转移基因与S.sclerotiorum在侵染植物时进行细胞壁水解和致病性有关.