13. Amino acids, Proteins and DNA
No description yet. This curated deck is ready for daily study.
Card preview (24)
What category do amino acids come under?
Amines and acids
What groups do amino acids have?
Amino and carbonyl groups
Do amino acids always only have one of each functional group?
No - they may also contain other functional groups
Why is the amine group in amino acids basic?
It has a tendency to accept protrons
Why is the carboxyl group in amino acids acidic?
It has a tendency to donate protons
What are the simplest amino acids?
α amino acids
What are α amino acids?
Amino acids with the amino group on the C atom adjacent to the carboxyl group (i.e. 2nd C atom)
Example of an α amino acid?
Alanine
What types of amino acids are there?
Alpha, beta, gamma
IUPAC name of alanine?
2-aminopropanoic acid
IUPAC name of aspartic acid?
2-amino butadioic acid
IUPAC name of lysine?
2,6 - diamino hexanoic acid
IUPAC name of phenylalanine?
2-amino 3-phenyl propanoic acid
IUPAC name of serine?
2-amino 3-hydroxyl propanoic acid
Which amino acid is not chiral?
Glycine
What does it mean that amino acids are chiral?
They have an asymmetric C atom and are optically active
What is zwitterion?
A dipolar ion
Why is zwitterion formed?
As a result of the lone pair of electrons on the nitrogen of amine group being able to accept a proton from the acid group
Do amino acids have both acidic and basic properties?
Yes
What is the isoelectric point of an amino acid?
The pH where the overall charge on the amino acid is zero
What pH are Zwitterions formed at?
Unique pH value for each amino acid
Is Zwitterion an acid-base property?
Yes
What will happen, in terms of Zwitterions, in acidic conditions?
• pH is lower than isoelectric point • so NH2 group protonated (acting as base) • COOH group unchanged
What will happen, in terms of Zwitterions, in basic conditions?
• pH is higher than isoelectric point • so COOH group deprotonated (acting as acid) • NH2 group unchanged