PDF-The amino acids

NCOO glycine Gly Galanine Ala Aproline Pro Psmall neutral amino acidslarge neutral amino acidsmethionine Met Mleucine Leu Lvaline Val Visoleucine Ile Ibra HCHNH3COO CHNH3C. CHAPTER 3, Part 1 . Amino Acids and Peptides . To know the structure and naming of all 20 protein amino acids. To know the structure and properties of peptides and the particularly the structure of the peptide bond.. Subunits (building blocks) of peptides and proteins. Neurotransmitters. Metabolic intermediates. glutamate. γ. -. aminobutyric. acid. (GABA). Proteins are synthesized from 20 ‘standard’ . α. -amino acids. Their names have 3- and 1-letter abbreviations.. THE EXCRETION OF AMMONIUM IONS. A part of NH4+ that is formed in the degradation of amino acids is used for the biosynthesis of nitrogen compounds. In most of the land living vertebrates the excess NH4+ is converted in urea and in that form is excreted. In birds and reptiles it is converted into uric acid and in aquatic animals it is directly excreted as urea.. B.2. Properties of 2-amino acids . (B.2.2). Zwitterion. (dipolar) . amino acids contain both acidic and basic groups in the same molecule . therefore, are . amphoteric. in nature (capable of behaving as acids or bases). (Foundation Block). Learning outcomes. What are the amino acids?. General structure.. Classification of amino acids.. Optical properties.. Amino acid configuration.. Non-standard amino acids.. Derivatives of amino acids.. Subunits (building blocks) of peptides and proteins. Neurotransmitters. Metabolic intermediates. glutamate. γ. -. aminobutyric. acid. (GABA). Proteins are synthesized from 20 ‘standard’ . α. -amino acids. Their names have 3- and 1-letter abbreviations.. amine group. Draw. a carboxylic acid group. Join. them together to form a molecule with an amine and . a carboxylic acid . group. Amino Acids. Building blocks of proteins. Two functional groups: a carboxylic acid and a primary amine. UNIT IV:. Nitrogen Metabolism. Part 2. Most of the nitrogen in the diet is consumed in the form of protein, typically amounting to 70–100 g/day in the American diet . Proteins are generally too large to be absorbed by the intestine. . 1. . Overview. The catabolism of the amino acids involves:. Removal of α-amino groups. . Breakdown of the resulting carbon skeletons.. The resulting compounds will be used to form seven intermediate products: . Amino Acids. Amino acid play A central role as building block of proteins.. Amino acids also converted to specialized products.. More than 300 different amino acids have been described in nature, only 20 are commonly found in mammalian proteins... . are organic molecules that are the building block of . . proteins. .. -There is 20 . α. -amino acids commonly found in . proteins. . ( . they . have a carboxyl group and an amino group . . . Amino acids are weak . polyprotic. acids . . Neutral amino acids are (. gly. , ala, threonine ) are treated as diprotic acids .. acidic amino acids (. glu. , asp,) are treated as . triprotic. acids .. Peptide bond formation. : . α-carboxyl group of one amino acid (with side chain R1) forms a covalent peptide bond with α-amino group of another amino acid . ( . with the side chain R2) by removal of a molecule of water. The result is : Dipeptide ( i.e. Two amino acids linked by one peptide bond). By the same way, the dipeptide can then forms a second peptide bond with a third amino acid (with side chain R3) to give . BSc 3. rd. year . AMINO ACIDS. C. lassification of amino acids . Classification according to nature of side chain. PREPARATION OF AMINO ACIDS. 1. Gabriel Phthalimide synthesis. 2. Strecker’s synthesis.