In: Biology
What if you wanted to test the effect of sucrose containing media on lac operon expression?
Design an experiment that would allow you to accomplish this.
Sucrose do not have any effect on lac operon expression. Lac operon expressed and produced three enzymes which requiered for the lactose metabolism. not for sucrose metabolism
1)lacZ produce β-galactosidase (LacZ), enzyme that break down the disaccharide lactose into glucose and galactose.
2)lacY produce Beta-galactoside permease (LacY), enzyme increases the permeability of the cell to β-galactosides.
3)lacA produce β-galactoside transacetylase (LacA), this enzyme transfers an acetyl group from acetyl-CoA to β-galactosides.
To check the effect of sucrose on lac operon by experimentaly. E.coli grow in sucrose and lactose containing media and check the OD 600 on spectrophotometer for bacterial growth. OD 600 is reached at 0.5 add the IPTG in both media to induce the lac promoter and .After 1 hrs check the β-galactosidase activity by O-nitrophenyl galactoside (ONPG) added in sucrose and lactose containing samples, and the amount of nitrophenol measure at A420 to estimate the β-galactosidase activity. β-galactosidase activity high at lactose containing E.coli sample and no β-galactosidase activity observed in sucrose containing E.coli sample.