Ch 18

Protein

Compound high molar Mass largely Consisting of amino acids linked together

enzyme

biological Catalyzes(accelerate) reactions (protein)

amino acid

Molecule contain amine group and carboxylic acid (Carboxylic acld donates proton to amine )

protein contains

carbon, hydrogen, nitrogen and sulfur

May contain phosphorus and Other elements

protein in our bodies

‘

blood brain muscle tissue, shin, hairand tooth enamal

enzymes

catalyze biological reactions

protein class

SPECTRS

Structural, protection enzyme contractile transport regulatory storage

essential amino acid

Must be obtained from diet

Zwitterion

electrically huetral Contains both + and - Charge

glycine

non Chiral

valine and Leucine

branched Chain amino acid

Isoleucine

essential amino acid

Phenylalanine, Tryptophan, Tyrosine

aromatic amino acid

Proline

Secondary amino acid

Serine

found at Active site of many enzymes

Threonine

sugar

Cysteine

has sulfure (SH group)

arginine

can accept protons

Structure of amino acid

allows it to act as acid and base

Isoelectric point

PH in amino acid exists as Zwitterion, has net charge of 0 at this PH

Peptides

Joining of two amino acid unit in peptide or Protein (strong and stable)

dipeptide

Chain of only two amino acid units

Tripeptide

3 amino acid Chains

N terminal end

Free amino group on the left

C terminal end

free carboxyl group on right

Polypeptide

Chain of 25-99 amino acids

Structural Classifications of proteins

Fibrous and globular

Fibrous protein

rigid insoluble in water (hair)

globular protein

Spherical Soluble in water (egg whites)

primary Structure

names and # of amino acid (not in depth)

Secondary Structure

Shows as pleated Sheet or helix

tertiary Structure

unique 3D Shape of Polypeptide Chain

quarternary Structure

arrangement of Multiple Subunits in protein

Insulin

hormone to metabolize glucose

B Pleated Sheet

Beta Strands held together side by side via hydrogen bonding by backbones

hemoglobin Chains

4 Polypeptide Chains

Ionic bonding

electrostatic attractions between + and - Charged groups

Dispersion force

instant unbalance Of electrons

Denaturation

change in protein Structure from PH or high temp renders Incapable of performing functions

catalyst

Increase Speed of Chemical reaction Without being consumed

substrate

compound enzyme reacts

hydrolase

Lipase catalyze hydrolysis lipids

proteases catalyze hydrolysis proteins

active site

Location on enzyme substrate binds to

Lock and key model

enzyme is rigid and only able to bond to Substrate that exactly fits

Induced fit model

enzyme can undergo a conformational change

Interactions between hexokinase and glucose

optimum PH

PH at Particular enzyme has max activity

reversable Inhibitor

substance that Inactivates enzyme by binding at active site through non covalent reversible Interactions

can dissociate from enzyme

types of reversible inhibitor

competethe and noncompetitive

competitive Inhibitor

Competes With Substrate for binding at Active site

L Form amino acid

found in proteins

Enantiomers

L amino acid

Nh3 is on left side

D amino acid

NH3 on right side

acid added to amino zwitterion

carboxylate group Captures hydrogen to be positive charged

base added to amino group Zwitterion

hydrogen is removed to become negative

Vit B1

beri beri

Vit B3

Pellegra

Vit B12

Pernicious anemia

folic acid B9

anemia

Vitamin c

Scurvy

water soluble Vitamins leave

piss

vit A

eyes

vit D

Bones

VIt K

blood clotting

Vitamin E

damage to cell Membrane

cofactor

non protein Component of enzyme necessary for proper functioning (non organic)

coenzyme

Cofactor that is organic

vitamin

OrganlC Compound essential in small amounts for metabolism

antioxidant

Substance preventing Oxidation

Reversible inhibitor

In activates enzyme by binding at active site through non covalent reversible interactions

can dissociate from enzyme

Competitive an non competitive

Irreversible Inhibitor

Inactivates enzyme by bonding covalently to specific group at active site

Cannot be reversed

competitive Inhibitor

resembles a particular Substrate and competes with it for active site to slow rate of reaction

non competitive inhibitor

can combine with free enzyme or Substrate at Active site to slow rate of reaction

Feedback Inhibition

normal biochemical process that makes use of non competitive inhibitors to control Some enzyme Actully

Alpha helix

coiled Structure stabilized by hydrogen bonds formed between carbonyl Oxygen atom

hydrogen bonding

bonding of electronegathe oxygen or nitrogen and a hydrogen Attacked to another Oxygen or nitrogen

Disulfide linkage

Covalent bond forms by oxidation and linkage of two Sulfur atoms from Cysteine residues

Attraction that determine shape of tertiary Structure

Ionic, hydrogen,disulfuric, and dispersion forces

enzyme Substrate complex

enzyme an molecule Collide to form this can be reversed

enzyme activity

catalytic activity include enzyme concentration, temperature, and PH

enzyme temperature

rise of 10°C can double reaction rate to a certain point due to denaturation

enzyme pH

Change in ph can denature and change catalytic activity

alters the degree Of Ionization