Introduction to Viromics

Overview

Teaching: 60 min
Exercises: 60 min

Objectives

• Summarize metagenomics and viromics

• Understand what are bacteriophages and how they fit into microbial communities

• Compare and contrast microbial and viral diversity

Video on viral metagenomics

Below is a lecture video introducing the concepts of metagenomics, microbial dark matter, and viromics. The case study covered in the video is about crAssphage, a type of bacteriophage that was first found using bioinformatics, by reanalyzing viromics data from the human gut by using the cross-assembly approach. The prevalence and implications of crAssphage are also discussed.

Exercise

Watch the lecture below and write down at least 3 questions and/or discussion points about it.

• Click on the image to see lecture video “Viral metagenomics: predicting phage-microbe interactions in the gut” by Prof Bas E. Dutilh (34 minutes):

Additional reading: Virus Bioinformatics (Pappas et al. 2021)

Exercise

Discuss with your neighbour:

1. What is metagenomics?
2. What is viromics?
3. What are bacteriophages and how prevalent and abundant are they?
4. What are the roles of phages in microbial communities?
   • more general, how do they influence the ecology and the environment
5. Explain at least three ways that phages can have an impact on bacteria.
   • More specifically, how do they influence their host (lytic/ temperate, HGT etc)
6. Name at least three differences between the evolution of viral and cellular organisms?

Key Points

• Viromics is the study of viruses, and in our case bacteriophages, using next-generation sequencing technologies

• Bacteriophages are diverse and ubiquitous across all biomes

• Bacteriophages have large implications on their environment including the human gut