Domains, structure function, and evolutions Flashcards
What is the structural similarity shown in Figure 4.23?
The structural similarity shown in Figure 4.23 is between Bacillus stereothermophilus lactate dehydrogenase and Escherichia coli malate dehydrogenase.
Example: (a) Bacillus stereothermophilus lactate dehydrogenase [PDB 1LDN]. (b) Escherichia coli malate dehydrogenase [PDB 1EMD].
What is the key concept about protein domains shown in Figure 4.24?
The key concept about protein domains shown in Figure 4.24 is that proteins can adopt an amazing variety of different sizes and shapes (tertiary structure) even though they contain only two basic forms of secondary structure.
Additional information: Proteins can have easily recognizable folds or more complex structures.
What is the relationship between domain structure and function?
The relationship between domain structure and function is complex. Often a single domain has a particular function, and in multifunctional enzymes, each catalytic activity can be associated with one or several domains found in a single polypeptide chain.
Example: In many cases, the binding of small molecules and the formation of the active site of an enzyme take place at the interface between two separate domains.
What are intrinsically disordered proteins?
Intrinsically disordered proteins are proteins and domains that have no stable three-dimensional structure. These proteins lack secondary and tertiary structure, which is encoded in the amino acid sequences.
Additional information: Intrinsically disordered proteins are quite common and have been subject to evolutionary selection.
