Question

Give an account on membrane proteins.

Answer 1

Membrane proteins are proteins that interact with, or are part of, biological membranes. They include integral membrane proteins that are permanently anchored or part of the membrane and peripheral membrane proteinsthat are only temporarily attached to the lipid bilayer or to other integral proteins.[1][2][3] The integral membrane proteins are classified as transmembrane proteins that span across the membrane and integral monotopic proteinsthat are attached to only one side of the membrane. Membrane proteins are a common type of proteins along with soluble globular proteins, fibrous proteins, and disordered proteins.[4] They are targets of over 50% of all modern medicinal drugs.[5] It is estimated that 20–30% of all genes in most genomes encode membrane proteins.[6][7]

Compared to other classes of proteins, the determination of membrane protein structures has remained a challenge in large part due to the difficulty in establishing experimental conditions where the correct conformation of the protein in isolation from its native environment is preserved

Answer 2

Transport proteins move molecules and ions across the membrane. They can be categorized according to the Transporter Classification database. Membrane enzymes may have many activities, such as oxidoreductase, transferase or hydrolase. Cell adhesion molecules allow cells to identify each other and interact.