3.3.13 amino acids proteins dna

Amphoteric they have acidic and basic properties
Amino acids (except glycine) are chiral molecules

1)Find longest carbon chain
2)Number carbons
3)Find position number of amine group
4)Find other groups
-ta da

They exist as zwitterions(have both positive and negative charge) at their isoelectric point
-COOH donates H to NH2

LOW PH= COO- takes a hydrogen and forms -COOH again
HIGH PH = Hydrogen from NH3$^+$ is removed forming NH2

Allows us to separate and identify amino acids as they have different solubilities

Polymers made up of amino acids with peptide link (C-N)
Two amino acids make a dipeptide with -COOH and -NH2 ends.

They have chiral centres(made up of amino acids) and donc only one enantiomer of substrate will fit into active site.
Active sites are stereospecific.

Nitrogen on adenine to H on Thymine. Oxygen on Thymine to H.
Oxygen on Guanine to H on cytosine. Oxygen on cytosine to Hydrogen on guanine. Nitrogen on cytosine to Hydrogen on guanine
Other base pairs dont work as partially charged atom would be too far/close

Anti-cancer drug with square planar complex with platinum ion and 2 ammonia& chloride ligands
It binds to DNA and prevents cell from reproducing .
Does this via:
Chloride ions displace and detach from complex and platinum can then bind to nitrogen on a guanine base in DNA. Done twice
This creates distortion in DNA strand preventing it from being unwind/copied

Can affect normal cells but these side effect can be reducesd via lower dosage and more targeted delivery
Still used in chemotherapy tratement due to long term benefit of it MAYBE eliminating cancer.