Microbial Evolution and Cell Biology

Course Aim

During the course, we will take a broad view of the immense diversity of single-celled organisms (both prokaryotes and eukaryotes), focusing on their evolution, ecology, genetics, biochemistry, and cell biology.

Course Description

Discover the vast genetic, cellular, and biochemical diversity of life that rests within single-celled organisms: the prokaryotes (bacteria and archaea) and microbial eukaryotes (protists). Through literature and laboratory exercises, explore the immense diversity of single-celled organisms (both prokaryotes and eukaryotes), focusing on their evolution, ecology, genetics, biochemistry, and cell biology, with a focus on the evolutionary history and major cellular innovations that occurred in single-celled organisms during the evolution of life.  Apply these insights to critically analyse research papers, design a research project, and write a grant application. In the laboratory, practice a range of techniques for studying cultured and field-sampled protists and prokaryotes, including microscopy and genomic approaches.

Course Contents

Theoretical part
1. What are cells and how they came to be the way they are (Evolutionary Cell Biology)
2. Origin of life, RNA world, genetic codes, and first ‘prokaryotic’ cells (LUCA)
3. Introduction to population genetics and phylogenetics (selection, mutation, drift, Muller’s ratchet, constructive neutral evolution, interpreting phylogenetic trees)
4. Evolution and diversity of bacteria and archaea
5. Asgard archaea, mitochondria, and the origin of the eukaryotic cell (LECA)
6. Mitochondrial evolution (ATP, hydrogenosomes/mitosomes, etc.)
7. Photosynthesis and diversification of plastids
8. Tree of life and eukaryotic supergroups (SAR, Excavata, Amoebozoa, Opisthokonta, Archaeplastida, and orphan clades)
9. Chemosynthesis and life in deep sea and hydrothermal vents
10. Prokaryotic vs. eukaryotic metabolism and lifestyles (phototrophy, heterotrophy, mixotrophy)
11. Major eukaryotic innovations (endomembrane system, nucleus, phagocytosis, cytoskeleton)
12. Microbial genomics, sex, and horizontal gene transfer
13. Evolution of multicellularity

Student Presentations
15 min presentation by every student about a selected paper (+10 min discussion). Students will be provided with a list of possible papers to present, including options for out-of-field students.

Laboratory exercises
Cultivation-dependent and cultivation-independent methods for studying microorganisms
a) Sampling microorganisms (marine, fresh-water, soil, animal-associated, etc.)
b) Culturing single-celled eukaryotes (phototrophs and predators)
c) Preparing a Winogradsky column with prokaryotes
d) Light and fluorescent microscopy (microorganisms sampled during field work and/or cultured)
e) Genome-resolved metagenomics: Nanopore/Illumina sequencing and real-time bioinformatics analysis of microbial diversity


30% participation and discussion, 20% presentation, 25% mid-term project, 25% final exam

Prerequisites or Prior Knowledge

Basic understanding of evolutionary and cell biology at the undergraduate level is assumed. The following courses offered at OIST are recommended to students who first want to review their knowledge: Molecular Biology of the Cell (B27) or Molecular Evolution (B23) and Evolution (B37)

Reference Books

One plus one equals one; John Archibald, Oxford University Press 2014
The tangled tree: A radical new history of life; David Quammen, Simon & Schuster 2018
I contain multitudes: The microbes within us and a grander view of life; Ed Yong, Ecco Press 2016