S. cerevisiae
Saccharomyces cerevisiae is type of yeast. It is a small, oval, single- celled organism that divides by budding to reproduce. It can divide existing as a haploid or diploid, depending on environment. S. cerevisiae is commonly used as baker's and brewer's yeast. It is part of the fungi kingdom and has a thick, waxy cell wall. The cells contain mitachondria but no chloroplasts.[1]
Its genome was sequenced in 1997 and was the first eukaryotic organism to have its genome sequenced. Its genome is approximately 13Mb (Mb=millions of base pairs) and 6000 genes. [2]
It has key characteristics which make it a useful model organism, a well established experimental biological system, for work in laboratories:
- it is a unicellular eukaryote that can be studied under the microscope
- it is small so is cheap and easy store
- it grows rapidly in a simple nutrient medium, having an approximate generation time of 80 minutes
- it can be genetically modified relatively easily, and has been extensively studied in the past, so lots is known about its genes.
- it shares homology with humans and has been used specifically in the research of the cell division cycle, gene expression, DNA replication and repair and cell signalling
- it has a large mutant collection
- it is non-pathogenic