Arginase Lab
Name: Fabiola Gonzales
ID#: 810004692
Lab Partner: Onecia Alexander
Date: Friday 23rd October 2015
Theory:
Arginase is an enzyme with the E.C. number 3.5.3.1 (Worthington 2015). This details it as a hydrolase enzyme that catalyses the cleavage of bonds through the addition of water. For this experiment, we pay close attention to the reaction where arginase catalyses the hydrolysis of arginine to ornithine and urea. This reaction is a part of the urea cycle and occurs in mammalian livers and sometimes kidneys. The reactions take place within the mitochondria and cytosol(Nelson and Cox 2008). To investigate these reactions we measure the amount of urea produced with the use a sample of liver extract containing arginase. This is then added to solutions of arginine and water. We use colorimetric determination and spectrophotometric analysis as a result of the red colour produced by the solution’s reaction with α-isonitrosopropiophenone (Davis and Mora 1968).
Manganese sulphate is added to the solutions as the outer manganese ions in reaction recovered the activity of arginase, which was lost in dissolving and dilution of the liver extract (Xie, et al. 2004). Perchloric acid is added to the tubes to halt the reaction where arginine is transformed to ornithine and urea. This occurs as a result of the reaction with the amine groups …show more content…
As a result, 1mL of enzyme produced 0.6538μmol of urea per minute. It was determined that the liver extract would have produced 4983.47μmoles of urea per minute. For this experiment, the tubes were entirely covered in foil since α-INPP is sensitive to light. The liver extract was also kept on ice to stabilise the enzyme due to the fact that enzymes are very sensitive to temperature. The enzymes perform optimally at 37 degrees Celsius thus the water bath was kept at this temperature. (Nelson and Cox
ID#: 810004692
Lab Partner: Onecia Alexander
Date: Friday 23rd October 2015
Theory:
Arginase is an enzyme with the E.C. number 3.5.3.1 (Worthington 2015). This details it as a hydrolase enzyme that catalyses the cleavage of bonds through the addition of water. For this experiment, we pay close attention to the reaction where arginase catalyses the hydrolysis of arginine to ornithine and urea. This reaction is a part of the urea cycle and occurs in mammalian livers and sometimes kidneys. The reactions take place within the mitochondria and cytosol(Nelson and Cox 2008). To investigate these reactions we measure the amount of urea produced with the use a sample of liver extract containing arginase. This is then added to solutions of arginine and water. We use colorimetric determination and spectrophotometric analysis as a result of the red colour produced by the solution’s reaction with α-isonitrosopropiophenone (Davis and Mora 1968).
Manganese sulphate is added to the solutions as the outer manganese ions in reaction recovered the activity of arginase, which was lost in dissolving and dilution of the liver extract (Xie, et al. 2004). Perchloric acid is added to the tubes to halt the reaction where arginine is transformed to ornithine and urea. This occurs as a result of the reaction with the amine groups …show more content…
As a result, 1mL of enzyme produced 0.6538μmol of urea per minute. It was determined that the liver extract would have produced 4983.47μmoles of urea per minute. For this experiment, the tubes were entirely covered in foil since α-INPP is sensitive to light. The liver extract was also kept on ice to stabilise the enzyme due to the fact that enzymes are very sensitive to temperature. The enzymes perform optimally at 37 degrees Celsius thus the water bath was kept at this temperature. (Nelson and Cox