1
Q
Metagenomics
A
- Metagenomics
- Study of genetic material from environmental samples
- Workflow
- Sample collection and DNA extraction
- Sequencing
- Preprocessing and quality control
- Taxonomic profiling and classification
- Functional annotation
- Assembly (optional)
- Data visualization and interpretation
- Statistical analysis
- Tools
- QIIME/QIIME2, Kraken2, MEGAN, MetaPhlAn
- FastQC, Trimmomatic, Cutadapt
- Prokka, MetaGeneMark
- Applications
- Human health
- Environmental studies
- Biotechnology
- Agriculture
- Conclusion
- Powerful tool for studying microbial communities
- Provides insights into diversity, function, and interactions
2
Q
Metagenomics Raw Data Preprocessing
A
- Metagenomics Preprocessing
- Cleaning and preparing raw sequencing data
- Steps
- Quality assessment (FastQC)
- Trimming and filtering (Trimmomatic, Cutadapt)
- Adapter and contaminant removal (Cutadapt, BBMap, Decontam, KneadData)
- Dereplication (USEARCH, VSEARCH)
- Host DNA removal (Bowtie2, BBMap)
- Merging paired-end reads (PEAR, Fastq-join)
- Normalization (DESeq2, rarefaction)
- Format conversion (SEQTK, FASTX-Toolkit)
- Importance
- Improves data quality and accuracy
- Removes errors and biases
- Ensures reliable downstream analysis
3
Q
Metagenomic Features
A
- Metagenomic Features
- Characteristics derived from metagenomic data
- Taxonomic Features
- OTUs, ASVs
- Taxonomic classification
- Phylogenetic analysis
- Functional Features
- Gene function prediction
- Functional annotation
- Metabolic pathway reconstruction
- ARGs, virulence factors
- Diversity Metrics
- Alpha diversity (Shannon, Chao1)
- Beta diversity (Bray-Curtis, UniFrac)
- Rarefaction curves
- Other Features
- Co-occurrence networks
- MAGs
- Phage and viral identification
- Conclusion
- Provide insights into microbial communities
- Essential for understanding diversity, function, and interactions
4
Q
Metagenomic Taxonomy Assignment
A
- Taxonomy Assignment
- Classifying metagenomic sequences into taxonomic groups
- Methods
- Marker-gene based (16S/18S rRNA, ITS)
- Shotgun metagenomics
- Tools
- Kraken, MetaPhlAn, Centrifuge
- QIIME, FastTree
- BLAST, UCLUST, VSEARCH
- Challenges
- Incomplete reference databases
- Low resolution
- Chimeric reads
- Short reads
- Conclusion
- Essential for understanding microbial communities
- Tools and methods are continuously improving
5
Q
Phylogenetic Trees
A
- Phylogenetic Trees
- Visualizing evolutionary relationships
- Key Components
- Taxa
- Branches
- Nodes
- Root
- Clades
- Building Trees
- Choosing data (DNA, protein, morphological)
- Aligning sequences
- Calculating distances
- Building the tree (distance-based, character-based)
- Evaluating the tree
- Importance
- Understanding evolutionary history
- Tracing disease evolution
- Identifying new species
- Making predictions about future evolution
- Conclusion
- Essential tool for studying life on Earth
