Class Notes (835,574)
United States (324,189)
Life Science (261)
LIFE 210 (38)

Amino acids, peptide bonds, protein folding and structure, Ras

5 Pages
Unlock Document

Life Science
LIFE 210
Paul Laybourn

31 August Overview – Proteins Last step in gene expression, are final product Constitute most of the dry mass of cells Carry out most of the cellular functions Structure dictates function Protein structure and function builds directly on the concepts and principles we covered in lectures 1 – 4 Building Blocks – amino acids (a.a.) 20 common a.a. Convention for writing/drawing is N to C General a.a. structure α carbon – central C of amino acid Carboxyl group on right Amino group on left R group – differs between a.a. Positive charge on amine group end, negative charge on carboxyl group end R Group Classifications Hydrophilic – polar Charged Acidic Negative charge Form H & ionic bonds Basic Positive charge Form H & ionic bonds Uncharged Form H bonds Hydrophobic Form hydrophobic interactions & van der Waals Special Are nonpolar Proton Basically no R group Glycene Form hydrophobic interactions and van der Waals Prolene Hydrocarbon chain bends back and bonds covalently to N of amine group Forms hydrophobic interactions & van der Waals Cystines Sulfhydryl group Forms disulfide bonds – stabling structures for proteins Some polar R groups are charged at the appropriate pH Peptide bonds link amino acids – dehydration synthesis Between C of carboxyl group & N of amine group Peptide Bonds in Protein Folding Have resonance Electrons jump back and forth – C=O or C=N Partial double bond Planar structure Restricted rotation R groups and C=O groups can clash Steric Protien Folding and Structure – four levels Denatured – unfolded Native – renatured or properly folded Primary Structure (1°) “Sequence” of amino acids (N to C) Met-Ala-Ser-etc. M-A-S-etc. n 20 possible sequences, where n = # a.a. Connected by peptide bonds (covalent) Secondary Structure (2°) – initial folding
More Less

Related notes for LIFE 210

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.