Blooms of Microcystis aeruginosa occur frequently in many freshwater ecosystems around the world,but the mechanism of recovery has not been fully understood.In our previous study,three benthic bacterial species(E.sp01...Blooms of Microcystis aeruginosa occur frequently in many freshwater ecosystems around the world,but the mechanism of recovery has not been fully understood.In our previous study,three benthic bacterial species(E.sp013,Ba.spD06,and Ba.spD24)were identifi ed capable of promoting the recruitment of M.aeruginosa.Here,we further investigated the transcriptional response of M.aeruginosa to the benthic bacteria in early phase of recruitment by means of RNA-Seq analysis.In total,5803803 unigenes on average length of 404 bp were obtained from the transcriptome of M.aeruginosa.There were 54982 unigenes identifi ed as benthic bacteria-responsive unigenes based on the expression level analysis.Results of the protein-protein interaction analysis(PPI)show that the hub genes of the benthic bacteria responsive unigenes mediated network were ribosomal proteins of 30S and 50S,and the most signifi cant functional module of the network was related to the ribosome.Both the unigenes encoding the translation initiation factors(IF-2,IF-3)and elongation factors(lepA,fusA,and tufA)were up-regulated to respond benthic bacteria.Therefore,it indicates that the benthic bacteria have a positive infl uence on activating the ribosome during the early recovery stage of M.aeruginosa.展开更多
Carbon resources play an important role in affecting the benthic bacterial community in shallow lakes. In this study, pyrosequencing was applied to compare bacteria phylogenic profile in incubated sediments with norma...Carbon resources play an important role in affecting the benthic bacterial community in shallow lakes. In this study, pyrosequencing was applied to compare bacteria phylogenic profile in incubated sediments with normal and exchanged organic detritus in macrophyte-dominated East Lake Taihu and algal-dominated Meiliang Bay. We observed significant bacteria species variations in sediments from two bays, regardless of treatments. RDA (Redundancy Analysis) analysis showed that sediment characteristics, especially concentrations of total nitrogen might account for this differentiation. Besides, algal-dominated Meiliang Bay sediment with addition of Vallisneria detritus exhibited higher bacterial species variations than the sediment amended with Microcystis detritus. To the contrary, sediments from macrophyte-dominated East Lake Taihu shared similar bacteria profile at all taxonomic levels and grouped together in MDS (multidimensional scaling) plots over the treatments with Vallisneria or Microcystis detritus addition into the sediment. We speculated that the different degradability of macrophyte detritus and algal detritus led to varied bacterial responses to exchanged organic resources and ultimately, the amounts, nutrient availability and degradability of organic resources may be main reasons for benthic bacteria community structure differentiation between the two states in shallow lakes.展开更多
针对长江南京段生态健康问题,于2019年平水期和丰水期在长江南京段干流的10个断面和21条入江支流进行采样,利用高通量测序的方法研究底质细菌群落的结构组成,构建了底质细菌群落完整性指数(benthic bacteria-index of biological integr...针对长江南京段生态健康问题,于2019年平水期和丰水期在长江南京段干流的10个断面和21条入江支流进行采样,利用高通量测序的方法研究底质细菌群落的结构组成,构建了底质细菌群落完整性指数(benthic bacteria-index of biological integrity,B-IBI)。结果表明:平水期长江南京段的生态健康要优于丰水期,长江干流断面要优于支流断面;TN、NH_(3)-N、NO_(3)^(-)、TOC与B-IBI呈显著负相关,Shannon指数、Margalef指数、Evenness指数与B-IBI呈显著正相关;研究建立的评价体系对于长江水质状况和生境有较好的指示作用;硬质护坡或河底对于入江支流细菌群落的多样性有负面影响,建议在确保防汛的基础上加强河道的生态修复。展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31472017,31272339)the Key Projects of Hunan Provincial Science and Technology Department(No.2014FJ2003)+1 种基金the Open Research Fund of Key Laboratory of Tropical Disease Control and Research,Ministry of Education in China(No.2018 kfkt03)the China Postdoctoral Science Foundation(No.2020M682573)。
文摘Blooms of Microcystis aeruginosa occur frequently in many freshwater ecosystems around the world,but the mechanism of recovery has not been fully understood.In our previous study,three benthic bacterial species(E.sp013,Ba.spD06,and Ba.spD24)were identifi ed capable of promoting the recruitment of M.aeruginosa.Here,we further investigated the transcriptional response of M.aeruginosa to the benthic bacteria in early phase of recruitment by means of RNA-Seq analysis.In total,5803803 unigenes on average length of 404 bp were obtained from the transcriptome of M.aeruginosa.There were 54982 unigenes identifi ed as benthic bacteria-responsive unigenes based on the expression level analysis.Results of the protein-protein interaction analysis(PPI)show that the hub genes of the benthic bacteria responsive unigenes mediated network were ribosomal proteins of 30S and 50S,and the most signifi cant functional module of the network was related to the ribosome.Both the unigenes encoding the translation initiation factors(IF-2,IF-3)and elongation factors(lepA,fusA,and tufA)were up-regulated to respond benthic bacteria.Therefore,it indicates that the benthic bacteria have a positive infl uence on activating the ribosome during the early recovery stage of M.aeruginosa.
文摘Carbon resources play an important role in affecting the benthic bacterial community in shallow lakes. In this study, pyrosequencing was applied to compare bacteria phylogenic profile in incubated sediments with normal and exchanged organic detritus in macrophyte-dominated East Lake Taihu and algal-dominated Meiliang Bay. We observed significant bacteria species variations in sediments from two bays, regardless of treatments. RDA (Redundancy Analysis) analysis showed that sediment characteristics, especially concentrations of total nitrogen might account for this differentiation. Besides, algal-dominated Meiliang Bay sediment with addition of Vallisneria detritus exhibited higher bacterial species variations than the sediment amended with Microcystis detritus. To the contrary, sediments from macrophyte-dominated East Lake Taihu shared similar bacteria profile at all taxonomic levels and grouped together in MDS (multidimensional scaling) plots over the treatments with Vallisneria or Microcystis detritus addition into the sediment. We speculated that the different degradability of macrophyte detritus and algal detritus led to varied bacterial responses to exchanged organic resources and ultimately, the amounts, nutrient availability and degradability of organic resources may be main reasons for benthic bacteria community structure differentiation between the two states in shallow lakes.
文摘针对长江南京段生态健康问题,于2019年平水期和丰水期在长江南京段干流的10个断面和21条入江支流进行采样,利用高通量测序的方法研究底质细菌群落的结构组成,构建了底质细菌群落完整性指数(benthic bacteria-index of biological integrity,B-IBI)。结果表明:平水期长江南京段的生态健康要优于丰水期,长江干流断面要优于支流断面;TN、NH_(3)-N、NO_(3)^(-)、TOC与B-IBI呈显著负相关,Shannon指数、Margalef指数、Evenness指数与B-IBI呈显著正相关;研究建立的评价体系对于长江水质状况和生境有较好的指示作用;硬质护坡或河底对于入江支流细菌群落的多样性有负面影响,建议在确保防汛的基础上加强河道的生态修复。
