Things that make you sick

Part I: nonliving things

Watch to learn Biological molecules

http://youtu.be/QWf2jcznLsY

Burgers and bloodDonated blood lately?

They ask about: Why?

Was there something in the air?

Prions

Isn’t meat full of proteins? What is special about this one?

Structure and function

Where to prions come from?

PrPc:

Cell membrane attachmentPlays a role in memory, movement, sleep/wake cycles and more

Results in change in function

PrPc: Common PrP

Where do prions come from?

Cooking does not disable or destroy prions—why?

Healthy protein prion

Protein structurePrimary structure:

What properties do amino acids have?

Unique properties of each amino acid determined by properties of functional groups at the “R side chain” or “R group”

General principle:

Functional groups

Make up parts of larger molecules

Amino acid properties

Why?

Amino acids with a negatively charged R group are acidic

Amino acids with a positively charged R group are basic

How are amino acids linked to form a sequence?

Joining amino acids forms a new water molecule

Peptide bond is a type of covalent bond

•

Electronegativity

Electronegativity difference ≤ 0.5:

Electronegativity difference > 0.5:

Relative Electronegativies

O Cl 3.2N C P 2.2H Na 0.9K 0.8

Element Electronegativity

Polarity

Despite the partial charge, these molecules are neutral: opposite poles balance each other out

Polarity is not the same as ions

Additional protein structures

The primary structure governs the formation and arrangement of other structures in a protein

Secondary structure:

Tertiary structure:

Quaternary structure: how multiple polypeptide chains are arranged into a single protein

Hydrogen bonding

Opposite partial charges weakly attractive

H bonds are forces that establish secondary and tertiary structural shapes

CJD progression

The process snowballs with time

Prion deposits build up and cause neurodegeneration

Spongiform encephalopathies

Caused by prions:

Mad cow disease, scrapie, kuru, Creutzfeldt-Jakob disease

The prion theory

Viruses• Very small: 100th the size of bacteria; 1000th the size of Eukaryotic cell

• Capsid:

• Variety of shapes and sizes

• Capsid proteins are used to attach to and gain entry into host cells

•

DNA vs. RNAMonomers?Functions?Structure?Bonds required to maintain structure?

Nucleotide structure/function

comparison

• Nucleotide functions: • •

Virus envelopes

• • • Lipids come from host cells; are mixed with viral proteins

Lipids

The main lipids of cell membranes and thus viral envelopes are phospholipidsOther types of lipids include steroids and triglycerides

Phospholipids

AmphipathicThree main components to the molecule

Function:

TriglyceridesTriglycerides: Two component moleculesFunction:

Fatty acids• Many types of fatty acids exist, varying in length of carbon chain, types of bonds, and amount of hydrogen

• All C-C bonds:

• Some C=C bonds:

What are trans-fatty acids?

Steroids

Function in nutrition, cellular signaling, building block of cells

End Biochem/Biomol