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Protein Structure Lab Report

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Protein Structure Lab Report
Task 1
• Describe the structure of an enzyme as a protein, in terms of tertiary/ quaternary structures.
1) Primary Structure

This is in reference to the order of way that amino acids are connected to form a protein. These are built up from 20 amino acids, and follow these structures o A carbon (the alpha carbon) bonded to the four groups below: o A hydrogen atom (H) o A Carboxyl group (-COOH) o An Amino group (-NH2) o A "variable" group or "R" group

2) Secondary Structure

This is in reference to the fold like structure of a polypeptide chain that gives the protein a 3d like shape. There is 2 types of secondary structure which are:
Alpha Helix
This would resemble a coiled spring which is secured by hydrogen bonding in a polypeptide chain.
Beta Pleated Sheet
This would resemble folds/pleats that is held together again by a hydrogen bond between a polypeptide of the folded chain that lie next to each other.

3) Tertiary
…show more content…
Indicate from your results, what the optimal temperature for enzyme activity was.
PH was 4 and Temperature was 70 degrees
c. What happens to the enzyme activity at temperatures higher than the optimal temperature/PH?

PH
Most proteins, and therefore enzymes, are active only within a narrow pH range usually between 5 and 9. Several factors are influenced directly by the pH in which the reaction takes place.
• the binding of substrate to the enzyme
• The ionization states of the amino acid residues involved in the catalytic activity of the enzyme.
• the ionization of the substrate
• Variation in the protein structure at extreme pH.
Temperature
The temperature range over which enzymes show activity is limited between the melting point (0oC) and boiling point (100oC) of water. If a temperature is too low, there can be no noticeable reaction rate since the enzyme is operating at a temperature far below its optimum. If the temperature at which the enzyme is operating at is well above 100oC, then thermal deactivation can

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