Effect of changing pH of pepsin on hydrolysis

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Effect of changing pH of pepsin on hydrolysis

Post by petey » Fri May 02, 2008 8:52 am


Did my A2 biology coursework. I compared the rate of hydrolysis between pepsin 2.8 and 7.0 using milk protein. Pepsin works in the stomach, so should have a faster hydrolysis rate in the acidic pH value. But when I measured transmission percentage I got a mean of 9% for 2.8 and 15 for 7.0 pH. My teacher had no answer, and suggested flipping the results, but I think this is dishonest and feels wrong. What reason/s could there be for this anomaly?

Many thanks,

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Post by Mhlengi » Fri May 02, 2008 10:55 am

Pepsin works best between pH 1.5 & pH 2.Pliz try that range your acidic pH.For most enzymes pH range is narrow and coincidental renaturing can occur givin rise to unexpected results.Partial denaturing can also occur if your ezyme mixture is nonhomogenous.So pliz try the mentioned pH range,and mix your enzyme solutions thoroughly.What method did u use to measure the rates of reaction?

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Post by mith » Fri May 02, 2008 2:04 pm

wow, that is dishonest...
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Post by DoctorStein » Fri May 30, 2008 11:42 am

The experiment should be repeated.
...and your teacher must be fired.

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