Metatranscriptomics—gene express profiling via DNA sequencing—is a powerful tool to identify genes that are actively expressed and might contribute to the phenotype of individual organisms or the phenome (the sum of...Metatranscriptomics—gene express profiling via DNA sequencing—is a powerful tool to identify genes that are actively expressed and might contribute to the phenotype of individual organisms or the phenome (the sum of several phenotypes) of a microbial community. Furthermore, metatranscriptome studies can result in extensive catalogues of genes that encode for enzymes of industrial relevance. In both cases, a major challenge for generating a high quality metatranscriptome is the extreme lability of RNA and its susceptibility to ubiquitous RNAses. The microbial community (the microbiome) of the cow rumen efficiently degrades lignocelullosic biomass, generates significant amounts of methane, a greenhouse gas twenty times more potent than carbon dioxide, and is of general importance for the physiological wellbeing of the host animal. Metatranscriptomes of the rumen microbiome from animals kept under different conditions and from various types of rumen-incubated biomass can be expected to provide new insights into these highly interesting phenotypes and subsequently provide the framework for an enhanced understanding of this socioeconomically important ecosystem. The ability to isolate large amounts of intact RNA will significantly facilitate accurate transcript annotation and expression profiling. Here we report a method that combines mechanical disruption with chemical homogenization of the sample material and consistently yields 1 mg of intact RNA from 1 g of rumen-incubated biofuel feedstock. The yield of total RNA obtained with our method exceeds the RNA yield achieved with previously reported isolation techniques, which renders RNA isolated with the method presented here as an ideal starting material for metatranscriptomic analyses and other molecular biology applications that require significant amounts of starting material.展开更多
Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway ...Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.展开更多
The Hypoxylaceae(Xylariales,Ascomycota)is a diverse family of mainly saprotrophic fungi,which commonly occur in angiosperm-dominated forests around the world.Despite their importance in forest and plant ecology as wel...The Hypoxylaceae(Xylariales,Ascomycota)is a diverse family of mainly saprotrophic fungi,which commonly occur in angiosperm-dominated forests around the world.Despite their importance in forest and plant ecology as well as a prolific source of secondary metabolites and enzymes,genome sequences of related taxa are scarce and usually derived from envi-ronmental isolates.To address this lack of knowledge thirteen taxonomically well-defined representatives of the family and one member of the closely related Xylariaceae were genome sequenced using combinations of Illumina and Oxford nanopore technologies or PacBio sequencing.The workflow leads to high quality draft genome sequences with an average N50 of 3.0 Mbp.A backbone phylogenomic tree was calculated based on the amino acid sequences of 4912 core genes reflecting the current accepted taxonomic concept of the Hypoxylaceae.A Percentage of Conserved Proteins(POCP)analysis revealed that 70%of the proteins are conserved within the family,a value with potential application for the definition of family boundaries within the order Xylariales.Also,Hypomontagnella spongiphila is proposed as a new marine derived lineage of Hypom.monticulosa based on in-depth genomic comparison and morphological differences of the cultures.The results showed that both species share 95%of their genes corresponding to more than 700 strain-specific proteins.This difference is not reflected by standard taxonomic assessments(morphology of sexual and asexual morph,chemotaxonomy,phylogeny),preventing species delimitation based on traditional concepts.Genetic changes are likely to be the result of environmental adaptations and selective pressure,the driving force of speciation.These data provide an important starting point for the establishment of a stable phylogeny of the Xylariales;they enable studies on evolution,ecological behavior and biosynthesis of natural products;and they significantly advance the taxonomy of fungi.展开更多
文摘Metatranscriptomics—gene express profiling via DNA sequencing—is a powerful tool to identify genes that are actively expressed and might contribute to the phenotype of individual organisms or the phenome (the sum of several phenotypes) of a microbial community. Furthermore, metatranscriptome studies can result in extensive catalogues of genes that encode for enzymes of industrial relevance. In both cases, a major challenge for generating a high quality metatranscriptome is the extreme lability of RNA and its susceptibility to ubiquitous RNAses. The microbial community (the microbiome) of the cow rumen efficiently degrades lignocelullosic biomass, generates significant amounts of methane, a greenhouse gas twenty times more potent than carbon dioxide, and is of general importance for the physiological wellbeing of the host animal. Metatranscriptomes of the rumen microbiome from animals kept under different conditions and from various types of rumen-incubated biomass can be expected to provide new insights into these highly interesting phenotypes and subsequently provide the framework for an enhanced understanding of this socioeconomically important ecosystem. The ability to isolate large amounts of intact RNA will significantly facilitate accurate transcript annotation and expression profiling. Here we report a method that combines mechanical disruption with chemical homogenization of the sample material and consistently yields 1 mg of intact RNA from 1 g of rumen-incubated biofuel feedstock. The yield of total RNA obtained with our method exceeds the RNA yield achieved with previously reported isolation techniques, which renders RNA isolated with the method presented here as an ideal starting material for metatranscriptomic analyses and other molecular biology applications that require significant amounts of starting material.
基金Supported by the National Key R&D Program of China(Nos.2018YFC1406704,2018YFD0900106,2018YFC1406700)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0302-4)the MOA Modern Agricultural Talents Support Project。
文摘Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.
基金the DFG(Deutsche Forschungsgemeinschaft)priority program“Taxon-Omics:New Approaches for Discovering and Naming Biodiversity”(SPP 1991)The bioinformatics support of the BMBF-funded project‘Bielefeld-Gießen Center for Microbial Bioin-formaticsBiGi(Grant Number 031A533)’within the German Network for Bioinformatics Infrastructure(de.NBI)is gratefully acknowledged.
文摘The Hypoxylaceae(Xylariales,Ascomycota)is a diverse family of mainly saprotrophic fungi,which commonly occur in angiosperm-dominated forests around the world.Despite their importance in forest and plant ecology as well as a prolific source of secondary metabolites and enzymes,genome sequences of related taxa are scarce and usually derived from envi-ronmental isolates.To address this lack of knowledge thirteen taxonomically well-defined representatives of the family and one member of the closely related Xylariaceae were genome sequenced using combinations of Illumina and Oxford nanopore technologies or PacBio sequencing.The workflow leads to high quality draft genome sequences with an average N50 of 3.0 Mbp.A backbone phylogenomic tree was calculated based on the amino acid sequences of 4912 core genes reflecting the current accepted taxonomic concept of the Hypoxylaceae.A Percentage of Conserved Proteins(POCP)analysis revealed that 70%of the proteins are conserved within the family,a value with potential application for the definition of family boundaries within the order Xylariales.Also,Hypomontagnella spongiphila is proposed as a new marine derived lineage of Hypom.monticulosa based on in-depth genomic comparison and morphological differences of the cultures.The results showed that both species share 95%of their genes corresponding to more than 700 strain-specific proteins.This difference is not reflected by standard taxonomic assessments(morphology of sexual and asexual morph,chemotaxonomy,phylogeny),preventing species delimitation based on traditional concepts.Genetic changes are likely to be the result of environmental adaptations and selective pressure,the driving force of speciation.These data provide an important starting point for the establishment of a stable phylogeny of the Xylariales;they enable studies on evolution,ecological behavior and biosynthesis of natural products;and they significantly advance the taxonomy of fungi.
