JSR - Bio 101 - Enzymes with Protein Review

Active site

Location where substrate binds to.

Denaturing

The shape or structure of the enzyme is changed due to extremes in temperature, pH or salinity; enzyme is unable to execute its function.

lock and key theory

One substrate fits one enzyme;

enzymes can only catalyze one biochemical reaction.

Enzyme

globular protein;

Catalyzes chemical reactions

Activation energy

the energy put into reactants to get a reaction started

Induced fit model

model that describes how enzymes may act on one or more similarly-shaped substrates and catalyze similar reactions

Substrate

reactant that binds to the enzyme's active site

Primary Structure

sequence of amino acids connected by peptide bonds

Secondary structure

one of two shapes formed as a result of hydrogen bonding between the carboxyl of one amino acid and the amine of another. .

Alpha Helix

coiled shape held together by hydrogen bonding between every fourth amino acid

Beta pleated sheet

accordion shape formed due to hydrogen bonds.

Tertiary Structure

complex globular shape due to R group interactions.

Quaternary structure

Two or more polypeptide chains held together by R group interactions

Insulin

Hormone (sends signals) - Controls sugar level

Antibodies (Immunoglobulins)

Defense - Part of immune response.

Spider Silk

Strong structural protein

Collagen

Strength and structure in skin

Amino acid sequence of polypeptides is coded for by ______________.

DNA

temperature

increases cause increasing activity up to the optimum; beyond optimun rapid denaturing occurs

pH

denaturing occurs on either side of optimum as increases or decreases disrupt hydrogen bonds

endergonic

reactions where products store more energy than the reactants

exergonic

reactions that release energy

metabolism

the sum of all chemical processes that occur in an organism

competitive inhibitor

A substance that reduces enzyme activity by binding to the active site in place of the substrate.

noncompetitive inhibitor

A substance that reduces enzyme activity by binding to a location away from the active site. Binding changes the shape of the active site so that the substrate can not bind.

example of a competitive inhibitor

sarin gas bind to the active site on acetylcholinesterase; prevents muscle contraction.

example of non-competitive inhibitor

cyanide binds to cytochrome c in cellular respiration; changes the shape of the active site such that the substrate cannot bind.

How can competitive inhibition be overcome?

add more substrate

end product inhibition

The regulation of metabolic pathways where the last product in a sequence of enzyme-controlled reactions becomes an inhibitor of one of the enzymes earlier in the sequence; prevents the production of two much product.

Number of amino acids used by living things to make proteins

20

condensation

process that combines amino acids into dipeptides or polypeptides by removing water

hydrolysis

process that breaks polypeptides or dipeptides into amino acids by adding water

denaturing

changing the shape of a protein through, pH, temperature, or salt concentration changes thus making it ineffective

metabolic pathway

chains or cycles of enzyme-mediated reactions

graph showing an endergonic reaction

graph showing an exergonic reaction

graph showing activation energy