Exam 3: Protein Structure and Function

Which of the following observations is the strongest argument in favor of the hypothesis that protein structure and function are correlated?

Refer to the following paragraph and Figure 3.1 to answer the following questions). Figure 3.1 Since structure correlates so well with function, biochemists are constantly looking for new ways to probe the complex structu proteins in order to understand what they do and how they do it. One of the most powerful techniques in existence today is X crystallography. The main difficulty with this technique is getting the protein to crystallize. Once crystallized, the protein is bombarded with X- rays to create a pattern that can be analyzed mathematically to determine the three- dimensional structure of the protein. This analysis has been performed by Krzysztof Palczewski on the protein rhodopsin, which is a light- sensitive protein found in species ranging from ancient bacteria archaea) to humans. The structure schematically shown above, where each letter represents an amino acid) is characterized by a single polypeptide chain with several a- helical segments that loop back and forth across the cell membrane. Another notable feature is the disulfide bond - S- S- ) that can be seen at the bottom of the third transmembrane segment. [Figure adapted from K. Palczewski et al., Science 289 2000): 739.] -What is the location of the C- terminus of the protein in Figure 3.1?

Which of the following best describes primary structure in proteins?

Refer to the following paragraph and Figure 3.1 to answer the following questions). Figure 3.1 Since structure correlates so well with function, biochemists are constantly looking for new ways to probe the complex structu proteins in order to understand what they do and how they do it. One of the most powerful techniques in existence today is X crystallography. The main difficulty with this technique is getting the protein to crystallize. Once crystallized, the protein is bombarded with X- rays to create a pattern that can be analyzed mathematically to determine the three- dimensional structure of the protein. This analysis has been performed by Krzysztof Palczewski on the protein rhodopsin, which is a light- sensitive protein found in species ranging from ancient bacteria archaea) to humans. The structure schematically shown above, where each letter represents an amino acid) is characterized by a single polypeptide chain with several a- helical segments that loop back and forth across the cell membrane. Another notable feature is the disulfide bond - S- S- ) that can be seen at the bottom of the third transmembrane segment. [Figure adapted from K. Palczewski et al., Science 289 2000): 739.] -Identify the location of the disulfide bond in Figure 3.1. What is the name of the amino acids that are forming this bond?

Why are polymerization reactions endergonic?

Three important functions of proteins are cell

Refer to the following paragraph and Figure 3.1 to answer the following questions). Figure 3.1 Since structure correlates so well with function, biochemists are constantly looking for new ways to probe the complex structu proteins in order to understand what they do and how they do it. One of the most powerful techniques in existence today is X crystallography. The main difficulty with this technique is getting the protein to crystallize. Once crystallized, the protein is bombarded with X- rays to create a pattern that can be analyzed mathematically to determine the three- dimensional structure of the protein. This analysis has been performed by Krzysztof Palczewski on the protein rhodopsin, which is a light- sensitive protein found in species ranging from ancient bacteria archaea) to humans. The structure schematically shown above, where each letter represents an amino acid) is characterized by a single polypeptide chain with several a- helical segments that loop back and forth across the cell membrane. Another notable feature is the disulfide bond - S- S- ) that can be seen at the bottom of the third transmembrane segment. [Figure adapted from K. Palczewski et al., Science 289 2000): 739.] -How many times does the protein in Figure 3.1 cross the cell membrane?

In solution, why do hydrolysis reactions occur more readily than condensation reactions?

Amino acid side chains R groups) with what characteristics) dissolve best in water?

Interactions between side chains R- groups) in a polypeptide are most important in stabilizing which of the following?

An amino acid has an R- group that does not have a positive or a negative charge but has an oxygen atom. Which of the following categories would best describe it?

A series of hydrophobic side chains will congregate together as a protein folds in an aqueous solution and be stabilized by

Recent technological advances have made it more feasible than ever to work out the three- dimensional structure of proteins. There is intense interest in this research field, called structural biology. Why?

When, and by whom, was the lock- and- key model of enzyme specificity developed?

Which of the following involves an increase in entropy?

When polymerization of a protein is complete, but the protein is still completely linear, what is the highest level of structure that has been completed?

How does the structure of an amino acid enable it to play its most important roles in cells?

What type of interaction is directly responsible for the formation of secondary structure?

An amino acid has an R- group that is composed of only carbon and hydrogen atoms. Which of the following categories would best describe it?

At the pH found in cells about 7.0), what happens to the amino group on an amino acid?