S. Cerevisiae Lab Report

The purpose of this experiment was to create complementation groups using 172a and 196ɑ mutants that could be used in determining the number of genes within the adenine biosynthesis pathway. The organism used for this experiment was Saccharomyces cerevisiae (S. cerevisiae) which is often called baker’s yeast. S. cerevisiae has several characteristics that make it an ideal organism to use in experiments. S. cerevisiae is a single-celled eukaryote capable of reproducing through mitosis or sporulation. This means that the yeast has both a haploid and a diploid stage. In yeast, the haploid cells are n=16 and the diploid cells are 2n=32. S. cerevisiae has two haploid mating types MATɑ and MATa. When the haploids mate, the diploids formed are heterozygous at the mating locus.
In this experiment, the genotypes of the two respective stains were172 MATa ade2 his3 leu2 trp1 ura3 can1 and 196 MATɑ ade2 his4 leu2 trp1 ura3 can1. Each strain has a mutation at the his locus which means that the yeast is unable to grow unless it is in
From the data, it was determined that there were 5-6 complementation groups. There were four absolute complementation groups: (A, B, N, Q, 1, 16, 17, 18, 22, 23, 24, 26, 27), (C, H, O, R, U, V, Y, Z, BB, 3, 6, 7, 9, 11, 12, 13, 15, 19, 21, 25), (D, F, I, 2, 8, 14, 20), and (J, K, L, 4, 5, 10, 28). E, G, M, P, W, X, and AA were determined to be possible revertants because they did not complement with any mutants from the opposite strain. S and T were determined to be 172a mutants that complemented all of the 196ɑ mutants. S and T could not be crossed since they were the same mating type. These 172a mutants could potentially be one or two groups. Each complementation group represents a gene located before the AIR intermediate. From the results of the experiment, it was determined that there were five to six genes that