OChem Chapter 12,14 Test – Flashcards
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Unlock answersFibrous Functions |
structure and contractive |
Fibrous Structure |
key: hiedrical structure
mostly non-polar amino acids are coiled together into super structures |
Globular Functions |
Metabolic Work: -Catalysis -Transport -Regulation -Protection |
Globular Structure |
Soluble (hydrophilic side chains) |
Fibrous Solubility |
insoluble in water |
Fibrous Structure (Primary…) |
|
α-Keratines (where?) |
hair, skin, nails, horns, hoofs, wool (Fibrous Proteins) |
Strength of Fibrous Proteins |
h-bonding and disulfide bridges between peptide chains |
Hemoglobin Structure |
4 polypeptide chains (2-α and 2-β)
alpha-helices separated by beta-turns |
Hemoglobin (where?) |
blood |
Myoglobin Structure |
Only 1 polypeptide chain |
Protein function ulitmately depends on… |
primary structure (amino acid sequence) |
Genetic Mutation |
An alteration in the DNA structure of a gene that may in turn produce a change in the primary structure of a protein |
Sickle-cell Hemoglobin |
Region critical to binding oxygen are NOT changed
Sickling is the aggregation of the hemoglobins (hydrophobic attractions between the hydrophobic pocket and residue 6 (Val)) |
Sickle-cell Anemia (where?) |
Western Africa likely because of high incidence of malaria |
Denaturation |
Loss of native conformation brought about by a change in envirnmental conditions, resulting in a loss of physiological function |
Denaturation alters which structures |
Alters secondary, tertiary and quaternary structures |
Digestion |
Breaks peptide bonds and alters primary structure
Not denaturation |
Denaturation (Globular vs. Fibrous) |
Globular protein have weaker secondary forces and thus are denatured easier. |
7 Methods of Denaturation |
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Increased Temp |
Increased motion disrupts non-covalent attractions
Example: cooking and sterilization |
UV and Ionizing Raditions |
Causes chemical reactions
Example: X-ray |
Mechanical Energy |
Example: Whipping Eggs |
Changes in pH |
Affects salt bridges |
Organic Chemicals |
Affects hydrophoic interactions
Example: Rubbing Alcohol |
Salts of Heavy Metals |
"Pb2+, Hg2+ and Ag+ react with sulfdryl groups and forms metal disulfide bridges
Example: Mecury Poisioning" |
Oxidizing and Reducing Agents |
Oxidizing: forming disulfide bridges Reducing: breaking disulfide bridges
Example: Perm |
Matabolism Functions |
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Catabolism |
Biochemical degradation/break-down of energy-containing compounds (energy releasing)
Exampe: Combustion of C6H12O6, opposite of photosynthesis |
Catabolism Process |
Nutrient molecules ↓ Precursor Molecules ↓ Acetyl CoA ↓ Water and Carbon Dioxide |
ATP |
adenine triphosphate
Used for energy required processes |
NADH |
nicotinamide adenine…
Used to make ATP |
Stages 2 & 3 |
use much of energy to create energy carrier molecules (ATP and NADH) |
Catabolism (oxidation or reduation) |
Oxidation process
low energy → high energy |
Anabolism (oxidation or reduation) |
Reduction process
high energy → low energy |
Enzymes |
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Active Site |
|
Anchor Points |
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Substrate |
Reactant molecule |
Complementarity |
Enzymes highly specific to their substrates |
Induced Fit |
Protein/enzyme changes space as the substrate binds |
Lock and Key |
Enzyme doesn't change shape, fits directly into active site |
True Substrate |
the reactant that in supposed to react |
Substrate Analog |
a molecule similar to the true substrate (size, shape, charge, polority) |
Competitive Inhibitor |
Substrate analog that binds in the active site (binds but doesn;t react) |
Non-competitive Inhibitor |
;alosteric;-a molecule that binds to a region other than the active site causing the conformation change which prevents the true substrate from binding |
Cofactors/Coenzymes |
ions/molecules that are needed to complete a protein's structure so that in can function |
Apoenzyme |
(apoprotein) polypeptide portion |
Haloenzyme |
Entire functional protein/enzyme
Cofactors/coenzymes + apoenzyme = haloenzyme |
Riboflavin |
in FAD |
Niacin |
in MAD |
Covalent Modification |
enzyme activity is regulated by covalently attaching a group which either activates or deactivates that enzyme's activity |
Feedback Inhibition |
when the product of one reaction serves as an inhibitor for a previous reaction |
Regulatory Enzymes |
enzymatic activity controlled by binding of activators/inhibitors |