proteins and nucleic acidspp
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Proteins and nucleicProteins and nucleicacidsacids
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MoreMore MacrmoleculesMacrmolecules
Proteins:Proteins:
Amino acid chainAmino acid chain polypeptidepolypeptide proteinprotein
Nucleic Acids:Nucleic Acids:
DNA, RNADNA, RNA
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What do proteins do?What do proteins do?
EnzymesEnzymes
Structural supportStructural support
StorageStorage
TransportTransportHormonesHormones
ReceptorsReceptorsMotor/contractileMotor/contractile
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What is a Protein?What is a Protein?Proteins are made up ofProteins are made up ofaminoaminoacidsacids (monomers for protein)(monomers for protein)
There are 20 total differentThere are 20 total differentamino acids.amino acids.
Amino acids have carboxylAmino acids have carboxyland amino groupsand amino groupsthe Rthe Rgroup/side chain differs andgroup/side chain differs anddetermines the amino acidsdetermines the amino acidsproperties.properties.
Amino Acids can beAmino Acids can be nonpolarnonpolar,,polar, or charged based onpolar, or charged based ontheir side chains.their side chains.
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ProteinsProteinsPolypeptidePolypeptide: polymer: polymer
of amino acidsof amino acids
One or moreOne or more
polypeptidespolypeptides
folded/coiled make afolded/coiled make a
wholewhole proteinprotein..
Amino acids are joinedAmino acids are joined
by dehydration:by dehydration:
forming aforming a
peptidepeptide
bondbond..
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Protein StructureProtein StructureWhat a protein can do is determined by itsWhat a protein can do is determined by its
shape!shape!
Protein structure or shape is determinedProtein structure or shape is determined
by the amino acids in the chain.by the amino acids in the chain.
Interactions between R groups causeInteractions between R groups causeattractions/bonds/overall shape or folding!attractions/bonds/overall shape or folding!
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Four Levels of Protein StructureFour Levels of Protein Structure
1.1. Primary Structure:Primary Structure:
The unique sequence ofThe unique sequence of
amino acids.amino acids.
The sequence of aminoThe sequence of amino
acids are determined byacids are determined by
DNA.DNA.
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Four Levels of Protein StructureFour Levels of Protein Structure
2.2. Secondary StructureSecondary Structure: Common repeated: Common repeated
coils and folds in the polypeptide chains.coils and folds in the polypeptide chains. Result fromResult from hydrogen bondshydrogen bonds between thebetween the
amino and carboxyl groups of theamino and carboxyl groups of the a.aa.a..
Two types:Two types:
helix (alpha):helix (alpha): coilingcoiling
pleated sheet (beta):pleated sheet (beta): two or more regionstwo or more regionslying side by sidelying side by side
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Four Levels of Protein StructureFour Levels of Protein Structure
3.3. Tertiary Structure:Tertiary Structure: the overall shapethe overall shape
resulting from interactions between the sideresulting from interactions between the sidechains (R groups)chains (R groups)
Types of interactions:Types of interactions:
Hydrophobic (with surroundings)Hydrophobic (with surroundings)
Hydrophilic (with surroundings)Hydrophilic (with surroundings)
vanvan derderWaalsWaals --Disulfide bridgesDisulfide bridges
Hydrogen BondsHydrogen Bonds --Ionic bondsIonic bonds
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Four Levels of Protein StructureFour Levels of Protein Structure
4.4. QuaternaryQuaternary
Structure:Structure:resulting fromresulting from
more than onemore than one
polypeptidepolypeptide
interacting withinteracting with
each other.each other.
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QuizQuiz
Build the modelBuild the model
On a separate sheet of paperdescribeOn a separate sheet of paperdescribe
how your model illustrates proteinhow your model illustrates protein1. Primary structure1. Primary structure
2. Secondary structure2. Secondary structure
3. Tertiary structure3. Tertiary structure
4.4. QuartenaryQuartenary structurestructure
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DenaturationDenaturation
Changing the confirmation of a protein/orChanging the confirmation of a protein/or
the ability for these interactions to occurthe ability for these interactions to occurcan make it noncan make it non--functional.functional.
Changes in pH, salt concentration,Changes in pH, salt concentration,
temperature etc. can cause a protein totemperature etc. can cause a protein to
denature.denature.
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DenaturationDenaturation
http://www.sumanasinc.com/webcontent/ahttp://www.sumanasinc.com/webcontent/a
nisamples/nonmajorsbiology/proteinstructunisamples/nonmajorsbiology/proteinstructure.htmlre.html
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Nucleic AcidsNucleic Acids
Nucleic acids code for protein. (OneNucleic acids code for protein. (One genegene
codes for a protein.)codes for a protein.)
Two types of nucleic acids:Two types of nucleic acids: Deoxyribonucleic Acid (DNA)Deoxyribonucleic Acid (DNA)
Ribonucleic Acid (RNA)Ribonucleic Acid (RNA)
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DNADNA RNARNA ProteinProtein
DNA codes for theDNA codes for the
synthesis of RNAsynthesis of RNA(also called(also called
messenger RNA ormessenger RNA or
mRNA)mRNA)
mRNA codes for themRNA codes for thesynthesis of proteinsynthesis of protein
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Nucleic Acids:Nucleic Acids: PolynucleotidesPolynucleotidesNucleic acids areNucleic acids are
polymers of nucleotidespolymers of nucleotides
Nucleotide:Nucleotide:
Nitrogenous baseNitrogenous base
A pentose (5 carbonA pentose (5 carbon
sugar)sugar)
And a phosphate groupAnd a phosphate group
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BasesBasesPyrimidinesPyrimidines::
One ring of six carbonsOne ring of six carbons
Cytosine (C), Thymine (T)Cytosine (C), Thymine (T)andand UracilUracil (U)(U)
PurinesPurines:: Two rings: six carbons andTwo rings: six carbons and
fivefive
Adenine (A), Guanine (G)Adenine (A), Guanine (G)
A always pairs with T or UA always pairs with T or U
G always pairs with CG always pairs with C
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SugarsSugars
Ribose (RNA)Ribose (RNA)
DeoxyriboseDeoxyribose
(DNA): lacks an(DNA): lacks anoxygen atom onoxygen atom on
the secondthe second
carbon.carbon.
Last part of a nucleotide: phosphate group
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Double helixAntiparallel
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