Soil is inhabited by a myriad of microorganisms,many of which can form supracellular structures,called biofilms,comprised of surface-associated microbial cells embedded in hydrated extracellular polymeric substance th...Soil is inhabited by a myriad of microorganisms,many of which can form supracellular structures,called biofilms,comprised of surface-associated microbial cells embedded in hydrated extracellular polymeric substance that facilitates adhesion and survival.Biofilms enable intensive inter-and intra-species interactions that can increase the degradation efficiency of soil organic matter and materials commonly regarded as toxins.Here,we first discuss organization,dynamics and properties of soil biofilms in the context of traditional approaches to probe the soil microbiome.Social interactions among bacteria,such as cooperation and competition,are discussed.We also summarize different biofilm cultivation devices in combination with optics and fluorescence microscopes as well as sequencing techniques for the study of soil biofilms.Microfluidic platforms,which can be applied to mimic the complex soil environment and study microbial behaviors at the microscale with highthroughput screening and novel measurements,are also highlighted.This review aims to highlight soil biofilm research in order to expand the current limited knowledge about soil microbiomes which until now has mostly ignored biofilms as a dominant growth form.展开更多
OBJECTIVE:To observe the effects of New Dayuan powder(NDYP)on Methicillin-resistant Staphylococcus aureus(MRSA)biofilms and the embedded bacteria in vitro.METHODS:2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2 H-tetrazol...OBJECTIVE:To observe the effects of New Dayuan powder(NDYP)on Methicillin-resistant Staphylococcus aureus(MRSA)biofilms and the embedded bacteria in vitro.METHODS:2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide(XTT)assays were used to study the effects of NDYP on developing MRSA biofilms:100μL of bacterial culture and100μL drug solution were added to wells of96-well plates.After 24 h of incubation,the plates were washed and XTT-phenazine methyl sulfate(PMS)was added to enable counting of the number of live bacteria in biofilms using a microplate reader.XTT assays were also used to explore the effects of NDYP on mature MRSA biofilms:100μL of bacterial culture were added to wells of 96-well plates.Bacteria were cultured in the plates for 24 h,and then drug solution was added.The plates were cultured for another 24 h,and then XTT-PMS was added to detect the number of live bacteria in the biofilms.Scanning electron microscopy(SEM)was used to observe the effects of NDYP on mature MRSA biofilms:washed and sterilized glass coverslips were added to 24-well plates.Bacterial culture was added.After 24 h of incubation,drug solution was added.After another 24 h of incubation,the samples were observed by SEM.RESULTS:XTT assays showed that the number of live bacteria in both developing and mature MRSA biofilms decreased significantly(P<0.01)after the administration of NDYP.SEM images showed that NDYP could destroy the structure of the bacteria and resulted in uneven thickness of MRSA biofilms.CONCLUSION:In vitro,NDYP has obvious inhibitory effects on the formation of MRSA biofilms and on mature biofilms.展开更多
基金supported by the National Natural Science Foundation of China(41877029)the National Basic Research Program of China(2016YFD0800206)the Fundamental Research Funds for the Central Universities(2662017JC008).
文摘Soil is inhabited by a myriad of microorganisms,many of which can form supracellular structures,called biofilms,comprised of surface-associated microbial cells embedded in hydrated extracellular polymeric substance that facilitates adhesion and survival.Biofilms enable intensive inter-and intra-species interactions that can increase the degradation efficiency of soil organic matter and materials commonly regarded as toxins.Here,we first discuss organization,dynamics and properties of soil biofilms in the context of traditional approaches to probe the soil microbiome.Social interactions among bacteria,such as cooperation and competition,are discussed.We also summarize different biofilm cultivation devices in combination with optics and fluorescence microscopes as well as sequencing techniques for the study of soil biofilms.Microfluidic platforms,which can be applied to mimic the complex soil environment and study microbial behaviors at the microscale with highthroughput screening and novel measurements,are also highlighted.This review aims to highlight soil biofilm research in order to expand the current limited knowledge about soil microbiomes which until now has mostly ignored biofilms as a dominant growth form.
基金Support by the Fundamental Scientific Research Funds for China Academy of Chinese Medical Sciences(Independent Topic Selection Project)
文摘OBJECTIVE:To observe the effects of New Dayuan powder(NDYP)on Methicillin-resistant Staphylococcus aureus(MRSA)biofilms and the embedded bacteria in vitro.METHODS:2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide(XTT)assays were used to study the effects of NDYP on developing MRSA biofilms:100μL of bacterial culture and100μL drug solution were added to wells of96-well plates.After 24 h of incubation,the plates were washed and XTT-phenazine methyl sulfate(PMS)was added to enable counting of the number of live bacteria in biofilms using a microplate reader.XTT assays were also used to explore the effects of NDYP on mature MRSA biofilms:100μL of bacterial culture were added to wells of 96-well plates.Bacteria were cultured in the plates for 24 h,and then drug solution was added.The plates were cultured for another 24 h,and then XTT-PMS was added to detect the number of live bacteria in the biofilms.Scanning electron microscopy(SEM)was used to observe the effects of NDYP on mature MRSA biofilms:washed and sterilized glass coverslips were added to 24-well plates.Bacterial culture was added.After 24 h of incubation,drug solution was added.After another 24 h of incubation,the samples were observed by SEM.RESULTS:XTT assays showed that the number of live bacteria in both developing and mature MRSA biofilms decreased significantly(P<0.01)after the administration of NDYP.SEM images showed that NDYP could destroy the structure of the bacteria and resulted in uneven thickness of MRSA biofilms.CONCLUSION:In vitro,NDYP has obvious inhibitory effects on the formation of MRSA biofilms and on mature biofilms.
