[Prep for MCAT]Biochemistry Week1

鑒於上學期genetics因為下半學期太浪最後太凄慘 決定開始整理這學期的筆記 順便開始MCAT複習。本學期持續更新Biochem，German，intro to sociology。暑假會整理上傳genetics。希望可以與眾多MCAT考生共勉。然後如果有學術問題歡迎大家指出，最後禁止轉載。

1/9: Review of chemistry and introduction to biochem:

1.Nomenclature of functional groups:

1) electrostatic interaction includes ionic interaction (full positive with full negative) and dipole-dipole (neutral molecule)

2)hydrogen bond

3)Van der Waals interaction (important for 3D structure of proteins)

4)hydrophobic interaction are an exclusion effect- entropy driven. Important implications for formation of membranes and amphipathic molecules.

3. features of biopolymers:

1) directional (DNA 5->3, protein N->C)

2)informational and 3) structure <-> function

Also, weak forces combine to maintain stable structure which undergoes conformational changes possibly.

Importance of condensation and hydrolysis in biopolymers.

4. Water chemistry:

1. polar, nonlinear, good polar solvent.

Lecture 2: amino acid and secondary structure

1) memorize structures and abbreviation of 20 amino acids

2) classification of amino acids into several groups:

Hydrophobic amino acids: Ala, Ile, Leu, Val, Gly, Pro, Met (contain sulfur), Cys (contain sulfur)

Aromatic amino acids: Phe, Trp, Tyr(slightly hydrophilic)

Alcohol: Ser , Thr

Amide: Asn, Gln

Acids: Asp (pK=4), Glu (4)

Bases: Arg (12.5), His (6), Lys (10.5)

3) Properties:

Cys and Tyr are weak acids

4) understand pI=(pK1+......pKn)/n, is the pH value of a molecule.

5) protein modification:

phosphorylation (Ser Thr, Tyr): change a hydroxyl group into a phosphate group.

hydroxylation (Lys, Pro): stabilization of structures

methylation (Arg, His, Lys): cell marker

Acetylation of histidine.

Ubiquitination (Lys)

6) Understand protein sequencing (Sanger Method)