Saccharomyces Cerevisiae ADE2

Quick Answer: Saccharomyces Cerevisiae ADE2 is a live culture of baker’s yeast listed under the ADE2 gene, the classic red/white colour marker of yeast genetics: strains with a mutated ade2 gene form red colonies on low-adenine medium, while cells with a working ADE2 gene stay cream.

Why ADE2 Is Useful in Genetics Teaching

The ADE2 gene codes for an enzyme in the pathway yeast uses to make adenine. When the gene is mutated (written ade2, in lowercase), the pathway is blocked and an intermediate builds up in the cells, where it is converted into a red pigment. The result is a visible phenotype: ade2 colonies turn red or pink when adenine in the medium runs short, while cells with a working ADE2 gene form cream colonies. Few organisms give students such a clear link between a single gene and what they can see on a plate.

In yeast naming, capital letters indicate the functional (wild-type) gene and lowercase letters the mutant. The listing writes the name in capitals, so confirm whether the culture supplied carries the ade2 mutation (red colonies) or is an ADE2 reference strain before planning practicals. The species name is normally written Saccharomyces cerevisiae, with a lowercase second word.

Saccharomyces cerevisiae is the species used in baking and brewing and is generally regarded as low risk for teaching laboratories, but it should still be handled with normal aseptic technique so cultures stay pure. The culture format, such as a slope, stab or plate, is not stated in the listing.

Practicals with an ADE2 Strain

• Demonstrating a gene-to-phenotype link through red and cream colony colour
• Showing how adenine in the medium changes colony colour, a gene-environment interaction
• Mutation experiments in which UV exposure produces colonies or sectors of a different colour
• Complementation crosses between two different red ade mutants, where the diploid turns cream if the mutations lie in different genes

Specifications

Handling and Storage

• Work beside a flame or in a clean cabinet with sterile loops so the culture stays pure.
• Keep the culture refrigerated and subculture onto fresh medium regularly, as appropriate for the format supplied.
• Incubate yeast plates at room temperature or around 30 °C; the red colour deepens over several days, especially after plates are moved somewhere cool.
• Sterilise used plates and cultures before disposal.

Why Choose LabEquip

Genetics and molecular biology teachers in senior schools and colleges use ADE2 yeast because it makes the effect of a gene visible within days. LabEquip lists the culture in General Lab Products; a yeast budding prepared slide shows the cells themselves, and the educational incubator keeps plates at a steady temperature.

Frequently Asked Questions

Why do ade2 yeast colonies turn red?

The ade2 mutation blocks adenine synthesis partway, so an intermediate called AIR (aminoimidazole ribotide) accumulates and is converted into a red pigment stored in the cell vacuole. Colonies with a working ADE2 gene do not build up the intermediate and stay cream.

Why does the red colour depend on the medium?

When the medium contains plenty of adenine, the cells take it up and switch off their own synthesis pathway, so less intermediate accumulates and colonies stay pale. Low-adenine media give the strongest red, which shows how environment affects phenotype.

What does ADE2 in capitals mean?

In yeast genetics, gene names in capitals refer to the functional, wild-type allele and lowercase names to mutants, so ADE2 is the working gene and ade2 a mutant form. Product names do not always follow this convention strictly, so the genotype is worth confirming.

How can the strain be used to study mutation?

Briefly exposing plated cells to UV light raises the mutation rate. Among the survivors, students look for colonies or sectors whose colour differs from the parent strain and discuss which genetic changes could explain them.

Why are some ade2 colonies white rather than red?

Pigment formation needs working mitochondria. Petite mutants, which have lost respiratory function, cannot make the pigment and form white colonies even though they carry ade2, a useful extension on how one pathway depends on another.

Is baker’s yeast safe to use in a school laboratory?

Saccharomyces cerevisiae is used in food and is generally regarded as low risk for teaching labs. Laboratory strains should still be handled with aseptic technique, never tasted, and sterilised before disposal as part of good microbiological practice.

Last Updated: September 2026