BCHE 3200: Protein Structure and Amino Acids PDF

Lecture #3 Protein structure, part 1 Amino acids – structure, properties and functions BCHE 3200: Principles of Biochemistry  What are proteins? Most versatile macromolecules in living systems that serve crucial functions in almos...

Lecture #3 Protein structure, part 1 Amino acids – structure, properties and functions BCHE 3200: Principles of Biochemistry  What are proteins? Most versatile macromolecules in living systems that serve crucial functions in almost all biological processes  Amino acids Amino acids Peptide bonds Proteins Protein gets broken down to individual amino acid Amino acids Peptide bond Peptide bond  Peptide bond Dehydration- condensation reaction Peptide bond Peptide bond formation is accompanied by the loss of a water molecule  Peptide bond By convention, the amino-terminal end is the beginning of the polypeptide chain. The polypeptide chain consists of a constant backbone (shown in black) and variable side chains.  Polypeptides or Proteins The local vitamin and nutrition store >tr|Q6LAN8|Q6LAN8_HUMAN Collagen type I alpha 1 is popular in my neighborhood. (Fragment) OS=Homo sapiens OX=9606 GN=COL1A1 PE=4 SV=1 Recently, I walked into this store and MFSFVDLRLLLLLAATALLTHGQEEGQVEGQDEDIPPI realized it is similar to the TCVQNGLRYHDRDVWKPEPCRI biotechnology companies in which CVCDNGKVLCDDVICDETKNCPGAEVPEGECCPVCPD many scientists purchase their GSESPTDQETTGVEGPKGDTGPR amino acids, media, and cell-culture GPRGPAGPPGRDGIPGQPGLPGPPGPPGPPGPPGLGG NFAPQLSYGYDEKSTGGISVPGP reagents. There were the usual MGPSGPRGLPGPPGAPGPQGFQGPPGEPGEPGASGP supplements to treat every disease MGPRGPPGPPGKNGDDGEAGKPGR you can imagine, but by far the most PGERGPPGPQGARGLPGTAGLPGMKGHRGFSGLDGA popular items showcased were KGDAGPAGPKGEPGSPGENGAPGQ amino acids. MGPRGLPGERGRPGAPGPAGARGNDGATGAAGPPGP TGPAGPPGFPGAVGAKGEAGPQGP Largest known protein is a muscle protein called titin with 27,000 letters (amino acids) Protein polymers or peptides Polypeptides  Amino acids Amino acids vary in: Size Charge Shape Hydrogen-bonding capacity Hydrophobic character Chemical reactivity  Amino acids Non-polar Polar Aliphatic Aromatic Uncharged Charged Aliphatic R groups Amino acid Abbreviation Symbol Glycine Gly G Aromatic R groups Alanine Ala A Amino acid Abbreviation Symbol Valine Val V Phenylalanine Phe F Leucine Leu L Tyrosine Tyr Y Isoleucine Ile I Tryptophan Trp W Methionine Met M Proline Pro P GAVLIMP!! First Year Writing!!  Non-polar amino acids Grandma Always Visits London In May For Winston’s PartYYY. G: Glycine (Gly) A: Alanine (Ala) V: Valine (Val) L: Leucine (Leu) I: Isoleucine (Ile) M: Methionine (Met) F: Phenylalanine (Phe) W: Tryptophan (Trp) P: Proline (Pro) Y: Tyrosine (Tyr) Amino acid Structure Feature Function Part of collagen Simplest amino acid Glycine Signaling molecule for nerve signals Achiral in brain, spinal cord Has a CH3 methyl for its R D-alanine is found in the cell walls of Alanine group bacteria Branched-chain amino Promote muscle growth, increase acid Valine athletic performance, and boost the Mostly metabolized in immune system muscle tissues Slows degradation of muscle tissue by Branched-chain amino increasing the synthesis of muscle Leucine acid proteins, Exacerbate symptoms of pellagra Branched-chain amino Isoleucine Associated with insulin resistance acid Amino acid Structure Feature Function First amino acid for making almost Methionine Contains sulfur every protein R group bound directly to Proline Makes collagen the α-amino group  Non-polar Aromatic R groups Amino acid Structure Feature Function People with phenylketonuria cannot convert Phenylalanine to Precursor for other amino Tyr Phenylalanine acids and neurotransmitters Untreated phenylketonuria leads to neurological problems, seizures, and learning disabilities Production of several important brain chemicals called Formed by the hydroxylation Tyrosine neurotransmitters, including of phenylalanine in the liver epinephrine, norepinephrine, and dopamine Starting point for the synthesis of many important biomolecules, R group of 9 carbons and one including NAD+ and the Tryptophan nitrogen in a structure known neurotransmitter serotonin, which as an indole ring converts into the sleep-related hormone melatonin  Amino acids Non-polar Polar Aliphatic Aromatic Uncharged Charged Polar uncharged R groups Negatively charged R groups Amino acid Abbreviation Symbol Amino acid Abbreviation Symbol Serine Ser S Aspartate Asp D Threonine Thr T Glutamate Glu E Cysteine Cys C Positively charged R groups Asparagine Asn N Amino acid Abbreviation Symbol Glutamine Gln Q Lysine Lys K Arginine Arg R Santa’s Team Crafts New Quilts Histidine His H Dragons Eat Knights Riding Horses Amino acid Structure Feature Function Found in beta-keratin. Form of an SH group known Main protein in nails, skin, and Cysteine as sulfhydryl hair. Making collagen. Body's proteins, enzymes and Serine Signaling molecule in the brain muscle tissue Helps with muscle function by Precursor to the amino acid Threonine decreasing involuntary muscle glycine and serine contractions. For normal development of the Asparagine brain Removing excess ammonia (a common waste product in the Glutamine body). Helps in immune system function, normal brain function and digestion. Amino acid Structure Feature Function Used for cold sores, animal feed because it is a limiting Essential amino acid amino acid when optimizing the Lysine Positively charged growth of certain animals, such as pigs and chickens, for meat production Signaling molecule in the brain, source of urea in the urea cycle. Arginine Positively charged source of called nitric oxide relaxing of blood vessel walls and improving blood flow. Histidine generate histamine. that promotes secretion of hydrochloric acid and pepsin in stomach to aid Often found in the active digestion. Potent vasodilator Histidine sites of enzymes released from sites of inflammation Positively charged or allergic reaction. To treat allergies, we use antihistamines. They prevent the binding of histamine to its receptors. Amino acid Structure Feature Function A precursor to threonine Excitatory neurotransmitter in the biosynthesis also connected brain Aspartate to the TCA cycle through fumarate and oxaloacetate Removal of ammonia from the body The most abundant Affects taste excitatory neurotransmitter Glutamate monosodium glutamate (MSG) in the vertebrate nervous Major role in shaping learning and system memory That’s All for Now Thank You Have a great day