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Week 7
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State the general formula for an α-amino acid as RCH(NH2)COOH.
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State that an amino acid exists as a zwitterion at a pH value called the
isoelectric point.
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State that different R– groups in α-amino acids may result in different
isoelectric points.
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Describe the acid–base properties of α-amino acids at different pH values.
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Week 7
General formula of an α-amino acid
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Week 7
Structures of some amino acids
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Week 7
Formation of a zwitterion from glycine
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Week 7
Acid–base reactions of an amino acid
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Week 7
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Explain the formation of a peptide (amide) linkage between α-amino acids to
form polypeptides and proteins.
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Describe the acid and alkaline hydrolysis of proteins and peptides to form αamino acids or carboxylates.
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Week 7
Formation of a dipeptide between glycine and alanine
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Week 7
Alternative reaction of alanine and glycine
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Week 7
Section of a polypeptide showing four different amino acids
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Week 7
Acid hydrolysis of a dipeptide
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Week 7
Alkaline hydrolysis of a polypeptide chain
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Week 7
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Describe optical isomers as non-superimposable mirror images about an
organic chiral centre.
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Identify chiral centres in a molecule of given structural formula.
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Explain that optical isomerism and E/Z isomerism are types of
stereoisomerism.
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Week 7
E and Z isomers of but-2-ene
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Week 7
The butan-2-ol molecule has a chiral carbon
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Week 7
Optical isomers of CH3CH2CH(NH2)CH3
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Week 7
Simplified three-dimensional representation of two optical isomers
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