Domains Flashcards
What is the ß meander motif?
An antiparallel B sheet composed of sequential strands connected by loops or turns.
Example: The order of strands in the B sheet is the same as their order in the sequence of the polypeptide chain.
What is the Greek key motif?
A design found on classical Greek pottery, it links four antiparallel B strands with strands 3 and 4 forming the outer edges and strands 1 and 2 in the middle of the sheet.
What is the B sandwich motif?
Formed when B strands or sheets stack on top of one another.
Example: Strands are connected by short loops and turns, but can also be formed by the interaction of two B sheets in different regions of the polypeptide chain.
What are domains in proteins?
Discrete, independently folded compact units in proteins.
Example: Domains may consist of combinations of motifs and are usually connected by loops or weak interactions formed by amino acid side chains.
What is the evolutionary conservation of protein structure?
One of the most important observations from the study of proteins, seen in single-domain homologous proteins from different species.
Example: Cytochrome c proteins show highly conserved tertiary structures across diverse species.
How are proteins grouped into families?
According to similarities in domain structures and amino acid sequences, with all members descending from a common ancestral protein.
