MCDB 1150 Class 18: Membrane Proteins

These flashcards cover key vocabulary terms related to membrane proteins, their functions, and properties, as outlined in the lecture notes.

Integral Membrane Proteins

Proteins that have at least one portion that is hydrophobic, allowing them to interact with the fatty acid tails of the phospholipid bilayer.

Peripheral Membrane Proteins

Proteins that interact with the membrane through non-covalent interactions, such as ionic and hydrogen bonds.

Lipid Anchored Proteins

Proteins that are covalently linked to a lipid or fatty acid, aiding in cell-cell communication and stabilization of membrane proteins.

Hydrophobic

Describes molecules that do not easily mix with water; cholesterol is hydrophobic.

Hydrophilic

Describes molecules that easily mix with water; amino acids can be either hydrophilic or hydrophobic.

Cholesterol

A type of lipid that helps to maintain the fluidity of the cell membrane and is transported in the bloodstream by LDL and HDL.

Transmembrane Protein

A type of integral protein that spans the entire membrane and can serve as a channel or transporter.

α-Helix

A common structural motif in proteins where the polypeptide chain coils into a spiral shape, often found in transmembrane proteins.

β-Barrel

A structural protein configuration where beta sheets are arranged in a barrel shape, often forming pores.

Amphipathic

Describes molecules that have both hydrophobic and hydrophilic regions, allowing them to interact with both water and lipid environments.

Glycolipid

A molecule consisting of a carbohydrate attached to a lipid; involved in cell recognition and signaling.

LDL (Low-Density Lipoprotein)

Often referred to as 'bad cholesterol'; it carries cholesterol from the bloodstream to cells.

HDL (High-Density Lipoprotein)

Known as 'good cholesterol'; it transports cholesterol from the cells back to the liver.

Pore

A channel in a membrane protein that allows specific molecules to pass through.

Channel Protein

A type of integral membrane protein that functions as a passageway for ions and small molecules.

Cytosol

The liquid component inside a cell where various organelles and proteins are suspended.

Extracellular Space

The area outside the cell membrane, involved in cell signaling and interaction.

Peptide Sequence

The order of amino acids in a protein that determines its structure and function.

Hydrophobicity

The property of a molecule to be repellent to water, significant in the formation of biological membranes.