BIOL2000 Lecture Notes - Lecture 3: Prentice Hall, Chemical Polarity, Alpha And Beta Carbon

13 views6 pages
20 Feb 2016
Department
Course
Professor
Lecture 3: Protein Structure and Function
January 27, 2016
Structure of Amino Acids
Non ionized form is the most common form
H2N (amino group)
COOH (carboxyl group)
H – hydrogen atom
R – side chain
In water (pH 7)
Amino groups ionize to NH3+ and Carboxyl group ionizes to COO-
The higher the pH, the more protons you lose
opKa increases; not good if it goes past 9.0
Some acids completely ionize completely in water
Carbon atoms are designated alpha and beta
oAlpha carbon: C that always bonds to amino and carboxyl groups
oBeta carbon: first carbon on attached R group
In pH 7, Lysine (NH3+ R group) could form a hydrogen bond or an ionic
bond (salt bridge)
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 6 pages and 3 million more documents.

Already have an account? Log in
Amino acid R-groups differ in electronegativity
When atoms of different electronegativity are bonded, they form polar, water
soluble molecules
Nonpolar when electronegativity of Hydrogen and Carbon are the same
In organic chemistry, electrons can be spread past their electron cloud
Lysine is positively charged while Aspartate is negatively charged ---------
The 20 major amino acids differ only in the variable side chain or R-group
attached to the central carbon
oGroups differ in their size, shape, reactivity, and interactions with
water and other molecules
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 6 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Notes+

Unlimited access to class notes and textbook notes.

YearlyBest Value
75% OFF
$8 USD/m
Monthly
$30 USD/m
You will be charged $96 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.