Proteins & Nucleic AcidsProteins & Nucleic Acids

Also Known As…Also Known As…

The Workers & DirectorsThe Workers & Directors

ProteinsProteins

Also Known As…Also Known As…

The “Rock Star” Worker MoleculesThe “Rock Star” Worker Molecules

Protein – Basic InfoProtein – Basic Info Proteins are the “working” molecules of the body. They Proteins are the “working” molecules of the body. They

can act as enzymes, aiding in chemical reactions, or be can act as enzymes, aiding in chemical reactions, or be structural components such as fingernails.structural components such as fingernails.

Proteins have a very specific 3-D shape which relates Proteins have a very specific 3-D shape which relates directly with their function – if this shape is not exact in directly with their function – if this shape is not exact in every way, the protein may not function at all.every way, the protein may not function at all.

On top of this, if the conditions in which the proteins On top of this, if the conditions in which the proteins must function are not just right – the protein may function must function are not just right – the protein may function at a lower capacity or not at all – even if it had the right at a lower capacity or not at all – even if it had the right shape to start.shape to start.

Think of proteins as the spoiled rock stars of the body – Think of proteins as the spoiled rock stars of the body – if they are not feeling right or the stage or dressing room if they are not feeling right or the stage or dressing room they have to perform in is a little off – the show may be they have to perform in is a little off – the show may be cancelled altogether.cancelled altogether.

Protein Building BlocksProtein Building Blocks

The monomer for the proteins is the The monomer for the proteins is the amino acidamino acid.. There are 20 different amino acids. They have the same There are 20 different amino acids. They have the same

“body” with a different “head”.“body” with a different “head”. The “body” of an amino acid, that is common to all 20 of The “body” of an amino acid, that is common to all 20 of

them, has the following parts:them, has the following parts: An An alpha (alpha (αα)carbon)carbon – the central carbon that holds it all – the central carbon that holds it all

together. There is always a together. There is always a hydrogenhydrogen bonded to this alpha bonded to this alpha carbon.carbon.

An An amino groupamino group – NH – NH22.. A A carboxyl groupcarboxyl group – COOH. – COOH.

There is also an There is also an R-GroupR-Group – this is the head of the amino – this is the head of the amino acid that is used to identify which of the 20 amino acids it acid that is used to identify which of the 20 amino acids it happens to be.happens to be.

Making ProteinsMaking Proteins Amino acids are bonded together using a Amino acids are bonded together using a

dehydration synthesis reaction – remove the dehydration synthesis reaction – remove the water and connect the leftovers.water and connect the leftovers.

The water comes from a “H” on the amino group The water comes from a “H” on the amino group and the “OH” of the carboxyl group.and the “OH” of the carboxyl group.

The bond that is made between the amino acids The bond that is made between the amino acids is called a is called a peptide bond.peptide bond.

This means, of course, that proteins are taken This means, of course, that proteins are taken apart by hydrolysis – stick the water back in and apart by hydrolysis – stick the water back in and break it up. This is what you do when you eat a break it up. This is what you do when you eat a hamburger and break down the protein of the hamburger and break down the protein of the beef.beef.

Protein MakingProtein Making

Protein Structure (Shape)Protein Structure (Shape)

Structural proteins tend to be linear.Structural proteins tend to be linear. The proteins that act as enzymes have a more The proteins that act as enzymes have a more

pronounced 3-D that is absolutely necessary for pronounced 3-D that is absolutely necessary for the proper function of the enzyme – damn rock the proper function of the enzyme – damn rock stars!stars!

There are 4 levels of protein structure…There are 4 levels of protein structure… Primary – straight line.Primary – straight line. Secondary – Secondary – αα--helix or helix or ββ-pleated -pleated sheet.sheet. Tertiary – “Kinky slinky” with folds.Tertiary – “Kinky slinky” with folds. Quaternary – A bunch of tertiary proteins acting as Quaternary – A bunch of tertiary proteins acting as

one.one.

Primary & Secondary StructurePrimary & Secondary Structure

Primary structure is the straight chain of amino Primary structure is the straight chain of amino acids that has just been built. This structure can acids that has just been built. This structure can be called a be called a polypeptidepolypeptide – many peptide bonds. – many peptide bonds. aa-aa-aa-aa-aa-aa-aa-aa-aa-aa-aa-etc…aa-aa-aa-aa-aa-aa-aa-aa-aa-aa-aa-etc…

Secondary structure sees this chain assume the Secondary structure sees this chain assume the αα--helixhelix (corkscrew) shape or a (corkscrew) shape or a ββ-pleated sheet-pleated sheet (fan) shape.(fan) shape.

The secondary structure is held The secondary structure is held together by together by hydrogen bonding between nearby carboxyl and hydrogen bonding between nearby carboxyl and amino groups within the polypeptide chain.amino groups within the polypeptide chain.

Tertiary & Quaternary StructureTertiary & Quaternary Structure

Tertiary structure occurs when the helix and sheet Tertiary structure occurs when the helix and sheet interact and twist around each other – it’s like a slinky interact and twist around each other – it’s like a slinky and a fan getting mangled together.and a fan getting mangled together.

Tertiary shape is held together by R-group bonding Tertiary shape is held together by R-group bonding within the chain and R-group interactions with the within the chain and R-group interactions with the environment.environment.

Tertiary structure is also aided by Tertiary structure is also aided by prosthetic groupsprosthetic groups that are inorganic compounds that act as a central point that are inorganic compounds that act as a central point for bonding within the protein.for bonding within the protein.

Quaternary structure occurs when a few tertiary Quaternary structure occurs when a few tertiary structures fit together to act as one functional unit.structures fit together to act as one functional unit.

Go Exact Or Go Home!!!Go Exact Or Go Home!!!

Proteins are the rock stars of the body but they Proteins are the rock stars of the body but they are very specific in their construction – if they are very specific in their construction – if they are not built exactly right – they may not work.are not built exactly right – they may not work.

This need for the exact 3-D shape is known as This need for the exact 3-D shape is known as specificityspecificity and it is based on two things: and it is based on two things: The number of amino acids.The number of amino acids. The order of the amino acids.The order of the amino acids.

If the protein is built exactly right it will function If the protein is built exactly right it will function properly unless environmental conditions get to properly unless environmental conditions get to tough.tough.

I Fall To Pieces…I Fall To Pieces… If the environment is too tough – the protein may If the environment is too tough – the protein may

denaturedenature – fall apart and lose that special 3-D – fall apart and lose that special 3-D shape.shape.

Denaturing may occur is response to:Denaturing may occur is response to: Temperature changes – especially heat.Temperature changes – especially heat. Changes in pH.Changes in pH. Changes in salt/ion concentration.Changes in salt/ion concentration.

In your body, a protein may denature but In your body, a protein may denature but chaperone proteinschaperone proteins will help reassume the will help reassume the proper shape.proper shape.

In a lab, there are no chaperone proteins so In a lab, there are no chaperone proteins so once the protein denatures – it is gone for good!once the protein denatures – it is gone for good!

Nucleic AcidsNucleic Acids

Also Known As…Also Known As…

The Directions on How to Make The Directions on How to Make Proteins Just Right.Proteins Just Right.

Nucleic Acids – Basic InfoNucleic Acids – Basic Info

They carry genetic information. This information They carry genetic information. This information determines all of your structural and functional determines all of your structural and functional characteristics.characteristics.

DNA – DNA – DDeoxyriboeoxyribonnucleic ucleic AAcid - houses the cid - houses the genetic code within the nucleus of the cell.genetic code within the nucleus of the cell.

RNA – RNA – RRiboibonnucleic ucleic AAcid - carries a copy of the cid - carries a copy of the code to the protein-making areas of the cell in code to the protein-making areas of the cell in the cytoplasm.the cytoplasm.

ATP – the cell’s energy – is also made from a ATP – the cell’s energy – is also made from a nucleic acid building block.nucleic acid building block.

Building DNA & RNABuilding DNA & RNA

The monomer for the nucleic acids is the The monomer for the nucleic acids is the nucleotidenucleotide..

The nucleotide has three parts:The nucleotide has three parts: 5-carbon Sugar5-carbon Sugar Phosphate groupPhosphate group Nitrogen-containing BaseNitrogen-containing Base

It‘s the sequence of the nitrogenous bases It‘s the sequence of the nitrogenous bases that provides the code/instructions for that provides the code/instructions for making the proteins.making the proteins.

DNADNA Double helix composed of two strands of nucleotides Double helix composed of two strands of nucleotides

held together by hydrogen bonds. The two strands are held together by hydrogen bonds. The two strands are antiparallelantiparallel to each other and are made of millions of to each other and are made of millions of nucleotides.nucleotides.

LadderLadder shape – shape – RailsRails - A series of alternating - A series of alternating phosphates and sugars linked by covalent bonds known phosphates and sugars linked by covalent bonds known as as phosphodiester bondsphosphodiester bonds. . RungsRungs of the ladder are of the ladder are made of the nitrogenous bases and their hydrogen made of the nitrogenous bases and their hydrogen bonds.bonds.

The nitrogenous bases involved with DNA are adenine, The nitrogenous bases involved with DNA are adenine, cytosine, guanine and thymine.cytosine, guanine and thymine.

The adenine and thymine pair up using two hydrogen The adenine and thymine pair up using two hydrogen bonds and cytosine and guanine pair up using three bonds and cytosine and guanine pair up using three hydrogen bonds (Chargaff’s Base-Pair Rule).hydrogen bonds (Chargaff’s Base-Pair Rule).

The nitrogenous bases can be either The nitrogenous bases can be either purinespurines (A & G) or (A & G) or pyrimidinespyrimidines (C & T or U in RNA). (C & T or U in RNA).

DNA StructureDNA Structure

RNARNA

RNA is a code-carrying, single-stranded RNA is a code-carrying, single-stranded molecule made of many nucleotides.molecule made of many nucleotides.

There are several differences between There are several differences between RNA and DNA.RNA and DNA.

RNA vs. DNARNA vs. DNA

DNADNA Double-stranded.Double-stranded. A, C, G & A, C, G & TT.. Deoxyribose - sugar.Deoxyribose - sugar. H-bonds present.H-bonds present. Works in nucleus.Works in nucleus.

RNARNA Single-stranded.Single-stranded. A, C, G, & A, C, G, & UU.. Ribose - sugar.Ribose - sugar. No H-bondsNo H-bonds Works in cytoplasm – Works in cytoplasm –

built in nucleus.built in nucleus.

RNA vs. DNA (Diagram)RNA vs. DNA (Diagram)

ATPATP

ATPATP ( (AAdenosine denosine TTriripphosphate) is the hosphate) is the cellular form of energy.cellular form of energy.

It is composed of three phosphates, a It is composed of three phosphates, a ribose sugar and an adenine base.ribose sugar and an adenine base.

The energy of the molecule is found in the The energy of the molecule is found in the bonds between the phosphate groups.bonds between the phosphate groups.

ATP StructureATP Structure

FIN!FIN!