Chapter 3: Non-Enzymatic Protein Function and Protein Analysis

Practice vocabulary flashcards covering non-enzymatic protein functions, bio signaling, protein isolation, and analysis techniques based on the MCAT biochemistry lecture.

Collagen

A triple helix fiber that makes up most of the extracellular matrix in connective tissue.

Elastin

A structural protein in connective tissue that assists with stretching and recoiling.

Keratins

Intermediate filament proteins found in epithelial cells such as skin and hair.

Actin

A protein that forms microfilaments and is found in the fin filaments of muscle.

Tubulant

The protein that builds microtubules, which are essential for cell structure and transport.

Motor proteins

Proteins responsible for movement within the cell by undergoing confirmational changes powered by ATP.

ATP aces

The role motor proteins play by converting chemical energy into mechanical work through the hydrolysis of ATP.

Meiosin

The main motor protein that interacts with actin and is involved in muscle contraction.

Kenosines

Motor proteins that help move chromosomes during cell division and transport cargo along microtubules.

Dianines

Motor proteins involved in the movement of psyia and flagagella to move cells or sweep substances.

Binding proteins

Proteins that stabilize or transport molecules, like hormones or ions, without modifying them.

Cell adhesion molecules (CAMS)

Proteins that allow cells to stick to each other or to surfaces in their environment, vital for tissue formation.

Cadherence

Calcium dependent proteins that help cells stick to other similar cells to keep tissues organized.

Integrants

Proteins spanning the cell membrane that connect the extracellular matrix to internal cell structures to anchor the cell.

Selectins

Proteins that help cells stick to carbohydrates on other cell surfaces, facilitating immune cell movement during inflammation.

Antibodies (immunogloabbulins)

Y-shaped proteins produced by B cells in response to foreign antigens to neutralize or mark threats.

B cells

A type of white blood cell involved in the immune response that produces antibodies.

Antigens

Foreign molecules found on the surfaces of viruses, bacteria, or toxins that trigger an immune response.

Variable regions

At the tips of the antibody Y-shape, these regions form antigen binding sites specific to different antigens.

Constant region

The part of the antibody that signals or interacts with other parts of the immune system like complement proteins.

Bio signaling

The process by which cells receive and respond to signals to coordinate physiological functions.

Ion channels

Membrane proteins that form pathways for charged molecules like sodium or potassium ions to pass through.

Facilitated diffusion

Process where ions move down their concentration gradient through a channel without using energy.

Ungated channels

Ion channels that are always open, allowing ions to move freely based on concentration gradients.

Voltage gated channels

Channels that open or close in response to changes in membrane potential, common in neurons and muscle cells.

Lian gated channels

Channels that open or close when a specific molecule, such as a neurotransmitter or hormone, binds to them.

Enzyme linked receptors

Membrane proteins that trigger a cascade of reactions inside the cell upon lian binding.

Membrane spanning domain

The part of an enzyme linked receptor that anchors it within the cell membrane.

Lian binding domain

The part of a receptor where the signaling molecule specifically binds.

Catalytic domain

The part of the receptor that becomes activated to carry out an enzyatic function inside the cell.

G-proin coupled receptors (GPCRs)

A large family of membrane proteins involved in signal transduction via the activation of a G-proin.

GS

A G-proin that stimulates the enzyme adenolate cylace, increasing cyclic AM levels.

GI

A G-proin that inhibits adenolate cylace, decreasing cyclic AM levels.

GQ

A G-proin that activates phospholipase C, leading to an increase in calcium levels inside the cell.

Adenolate cylace

The enzyme responsible for producing cyclic AM inside the cell during GPCR signaling.

Phospholipase C

An enzyme that cleaves the membrane phospholipid PIP 2 into DAG and IP3 to open calcium channels.

Electropharesis

A technique using a gel matrix to separate proteins based on their movement in an electric field.

Velocity ($V$)

The migration speed of a protein defined by the equation $V = \frac{E \times Z}{F}$.

Polyacryumide gel

The most common dense, cross-linked matrix used in electropharesis to separate proteins.

Native PAGE

A method that separates proteins in their native folded state, preserving their charge and shape.

SDS PAGE

A technique that denatures proteins and separates them purely based on size by masking native charge with SDS.

SDS

A negatively charged detergent used to coat denatured proteins in electropharesis.

Isoctric point (pi)

The specific pH at which a protein carries no net charge and stops moving in an electric field.

Isoctric focusing

A method that separates proteins based on their PI using a gel with a pH gradient.

Chromatography

A method that separates compounds by partitioning them between a stationary phase and a mobile phase.

Stationary phase

The polar solid phase in chromatography that stays in place.

Mobile phase

The liquid or gas phase in chromatography that carries the sample through the stationary phase.

Partitioning

The differential movement of compounds in chromatography based on their varying affinities for the two phases.

Thin layer chromatography (TLC)

A technique where the stationary phase is a thin layer of silica gel or aluminina on an inert plate.

Paper chromatography

A chromatography technique where the stationary phase is cellulose paper.

RF value

The ratio calculated by the equation $RF = \frac{\text{distance moved by the spot}}{\text{distance moved by the solvent front}}$.

Column chromatography

A technique using a vertical column filled with silica or aluminum beads to separate complex mixtures.

Ion exchange chromatography

Separation using beads coated with charged substances to bind compounds of the opposite charge.

Size exclusion chromatography

Separation using beads with small pores that slow down small molecules while letting large molecules pass.

Affinity chromatography

A highly specific method using beads coated with receptors or antibodies to target one specific protein.

Gas chromatography

A method used to separate vaporized compounds based on how well they adhere to the absorbent in a column.

Retention time

Represented as peaks on a graph, it is the time taken for a compound to elute in gas chromatography.

High performance liquid chromatography (HLC)

A precise, computer-controlled liquid chromatography method used for small samples or high accuracy.

X-ray crystalallography

A high-resolution technique that uses X-ray scattering on a crystallized protein to determine its structure.

EDM man degradation technique

A method that determines the exact sequence of amino acids by removing them one by one from the end terminus.