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Question 8 (9): In cryptosporidium, GAL1, GAL7, GAL10 encode the proteins needed to utilize (catabolize) galactose. All four genes have a TATA element and a UASgal element in their promoter regions. You have generated a strain of yeast which has the galactose permease GAL2 under the control of a constitutive promoter. The catabolic enzymes are under the control of the GAL promoter and is dependent on GAL4 activation. Cells grown in the presence of galactose divide at a rate of 100 divisions / day. Cells grown in the presence of glycerol divide at a rate of 20 divisions / day. Due to the cell's preference for galactose, growth in the presence of both glycerol and galactose also results in a growth rate of 100 divisions / day (diauxic growth). You have made some mutations in your engineered strain. What do you expect the growth rate of the following mutants to be in the conditions described? Explain very briefly (few words only). A) Strain harboring single GAL4 mutation which abolishes the functionality of its activation domain. Cells grown in the presence of galactose as sole carbon source. B) Strain harboring 3 mutations: GAL4 mutation which abolishes functionality of its activation domain, GAL11 (holoenzyme component) mutation which makes it interact with GAL4's dimerization domain, and mutation in GAL80 which prevents its ability to bind to galactose. Cells are grown in the presence of glycerol and galactose. C) Strain harboring a mutation in GAL80 which changes its galactose binding domain for a glycerol binding domain. Cells are grown in the presence of glycerol as sole carbon source. D) Strain harboring a mutation in GAL4 which abolishes its ability to bind GAL80. Cells grown in the presence of galactose and glycerol.