ou know that very high and very low pH values are outside of the normal ranges for life and the biochemistry of life (especially protein catalysts, namely enzymes). This is largely due to the effects of pH on interactions of the backbones of peptide chains, R-group interactions and polypeptide assembly/folding (secondary to quaternary protein structure of polypeptide chains). What do you think will happen to the shape of the active sites in the enzyme at high or low pH?

ou know that very high and very low pH values are outside of the normal ranges for life and the biochemistry of life (especially protein catalysts, namely enzymes). This is largely due to the effects of pH on interactions of the backbones of peptide chains, R-group interactions and polypeptide assembly/folding (secondary to quaternary protein structure of polypeptide chains). What do you think will happen to the shape of the active sites in the enzyme at high or low pH?

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter4: Cells

Section: Chapter Questions

Problem 1ITD

See similar textbooks

Similar questions

The amino acid histidine is often found in enzymes. Depending on the pH of its environment, sometimes histidine is neutral and at other times it acquires a proton and becomes positively charged. Consider an enzyme with a histidine side chain that is known to have an important role in the function of the enzyme. It is not clear whether this histidine is required in its protonated or its unprotonated state. To answer this question, you measure enzyme activity over a range of pH, with the results shown in below. Which form of histidine is necessary for the active enzyme?
You are studying a catalytic protein which contains two ion clusters, one cluster contains 2 Cu+3 cations, while the second contains 4 SO3-2 anions. One cluster is held in place deep in the active site of the protein, while the second is near the surface of the protein and involved in regulating the enzyme. Explain how each of the secondary structure elements could bind to these ions, include the region of the secondary structure element or the amino acids involved in this binding.
Select the true statements regarding the position of participating regions of an enzyme. Within the active site of an enzyme, non-amino acid additions such as cations are in optimal positions to bind and hold onto substrates. Within the allosteric site of an enzyme, amino acid side chains do not react chemically with substrates. Within the active site of an enzyme, non-amino acid additions are in optimal positions to chemically react with substrates. Within the allosteric site of an enzyme, amino acid side chains are in optimal positions to bind and hold onto substrates.
In order to understand the relationship between enzyme structure and function, researchers often study mutations that swap one amino acid for another. In one enzyme, function is retained if a particular amino acid is replaced by one that has a nonpolar R group, but function is lost if the amino acid is replaced by one with a polar R group. Why might that be?
Two isoforms of an enzyme were discovered; isoform-1 produces a hormone that causes muscle spasms and isoform-2 makes a different hormone (from the same substrate) that lowers cholesterol levels. a) What strategy would you employ as a medicinal chemist to develop a drug that prevents muscle spasms without raising cholesterol levels? The active sites of isoform-1 and -2 are the same except isoform-1 has a cysteine residue and isoform-2 has a phenylalanine residue at that same position. b) What two approaches would you take for designing a muscle spasm drug without a cholesterol level increase side effect?
A certain enzyme catalyzes a reaction that uses the compound shown as a substrate. Would the walls of the active site be likely to contain nonpolar, polar, or charged amino acid side chains? Why?
Select the false statements regarding the position of participating regions of an enzyme. Within the allosteric site of an enzyme, non-amino acid additions are in optimal positions to chemically react with reversible inhibitors. Within the allosteric site of an enzyme, amino acid side chains have the ability to bind and hold onto activators. Within the allosteric site of an enzyme, amino acid side chains are in optimal positions to chemically react with substrates. Within the active site of an enzyme, non-amino acid additions such as cations are in optimal positions to bind and hold onto substrates.
Select the false statements regarding the position of participating regions of an enzyme. Within the allosteric site of an enzyme, non-amino acid additions are in optimal positions to chemically react with reversible inhibitors. Within the allosteric site of an enzyme, amino acid side chains have the ability to bind and hold onto activators. Within the allosteric site of an enzyme, amino acid side chains are in optimal positions to chemically react with substrates. Within the active site of an enzyme, non-amino acid additions such as cations are in optimal positions to bind and hold onto substrates. Select the false statements from the following regarding the RNA hypothesis of chemical evolution. RNA are diverse molecules in the modern cells able to provide genetic instructions while catalyzing anabolic and catabolic reactions. RNA is not able to hydrogen bond to itself. DNA became a storage molecule after ancestral RNA…
Modern medicine now uses insulin analogues (where one or more of the amino acid residues has been changed) in the treatment of diabetes. In one such analogue, glargine insulin, the changes have increased the isoelectric point of the enzyme from 5.4 to 6.7, thereby reducing its solubility at physiological pH. Explain how changes in the primary amino acid sequence can alter the pI and solubility of the analogue without altering its interaction with blood glucose.
Streptokinase is an enzyme produced by Streptococci bacteria and is used to digest fibrin clots. It is therefore very effective at eliminating blood clots that cause heart attacks and strokes. Why does a physician not worry that injecting streptokinase will also destroy healthy tissue in their patients? – this answer should discuss the specificity of enzymes for their substrates, defined by the shape of the active site.
Select the true statements regarding the position of participating regions of an enzyme. (you may select more than one) Within the active site of an enzyme, non-amino acid additions such as cations are in optimal positions to bind and hold onto substrates. Within the allosteric site of an enzyme, amino acid side chains do not react chemically with substrates. Within the active site of an enzyme, non-amino acid additions are in optimal positions to chemically react with substrates. Within the allosteric site of an enzyme, amino acid side chains are in optimal positions to bind and hold onto substrates.
The dynorphins are a group of opioid peptides that play an important role in changes in the brain associated with cocaine addiction. One of these peptides, dynorphin A, contains the following amino acid sequence: Tyr–Gly–Gly–Phe–Leu–Arg–Arg–Ile–Arg–Pro–Lys–Leu–Lys. Draw the amino acids and peptide fragments formed when dynorphin A is treated with each reagent or enzyme: (a) chymotrypsin; (b) trypsin; (c) carboxypeptidase; (d) C6H5N=C=S.