- p.35 hydroxyl/FUNCTIONAL GROUPS
- biochem
- carbohydrates: mono, di, polysaccharides
- lipids: mono, di, triglyceride
- proteins: 20 basic amino acids
- nucleic acids: DNA, RNA
- carbohydrate
- (CH2O)n; 3-7 units long
- 3 C → D-glycerose
- 4 C → therose
- 5 C → lyxose, D-xylose, D-arabinose, D ribose
- 6 C → galactose, D-mannose, glucose, fructose
- hexose
- pentose
- heptose
- glucose 3D: boat, chair
- fructose (2x sweet glucose)
- amylose: helical coil glucose (only α 1→4)
- amylase cleave @ branch point
- animal starch: glycogen (more branches), most in muscles
- glycogen smaller than starch (plant)
- lipids: oil, fat
- two subunits: glycerol (3 OH), fatty acid
- # fatty acids: mono, di, tri glycerides
- glycerine
- butyric acid
- (hexanoic) caproic acid
- palmitic (16-C)
- stearic (18-C)
- oleic (18-C) isomers
- 3 types of cellular lipid
- structural lipid-cell membrane, etc.
- neutral fat-stored, males: 15%, females: 21%
- brown fat in infants between scapulas, nape of neck, great vessels in thorax/abdomen for heat production
- essential fatty acid (20 C's), polyunsaturated, tested in animals
- linolenic
- linoleic
- arachidonic
- olive oil: mono and diglyceride
- ectotherm: unsaturated
- homotherm: saturated (beef)
- energy content: fat 9 calories/gram, more C-C & C-H; carbs 4.3 calories/gram, more C-OH
- phospholipids: diglyceride, phosphate at 3rd OH
- major membrane part
- PO4 is water soluble
- fatty acids are hydrophobic (bilayer of phospholipid)
- cholesterol mixed in to give strength to cell membrane, membrane protein and carbohydrates
- waxes: cuticles; long chain fatty acids (30-40 C)
- proline: ring so bends polypeptide chain
- proteins
- building materials (hair, connective tissue, globular protein)
- selective corners in cell membranes, usually globular proteins
- cell recognition, globular w/polysaccharide chains attached
- muscle contraction actin & myosin (most abundant)
- catalysts, enzymes major groups
- control of DNA and gene expression/repressor protein control DNA
- proteins differ in
- # amino acids (usually > 100 AA to be a protein)
- sequence of AA's in protein
- 8 essential amino acids in humans (diet), rest made from enzymes we have
- breaking disulfide bonds-irrevocable denaturation
- dehydration synthesis & hydrolysis
- dehydration 3x for triglycerides, once for each OH
- elongation occurs on carboxyl end (COOH on right)
- buffers= weak acid + salt
- Chemicals that maintain pH values within narrow limits by absorbing or releasing hydrogen ions, prevent rapid shifts which would be harmful to protein structure for biological activity
- Proton donor and acceptor systems serve as buffers preventing marked changes in hydrogen ion concentration (pH).
- Brönsted-Løwry, acids are proton-donors
- life depends on buffers to maintain homeostasis
- examples:
- acetic acid & Na acetate
- H2O3 & NaHCO3
- if base (OH) is added, extra H is dissociated
- phosphate buffers pH 5.3 to 8.0 (range used in enzyme lab), used in biochemical research
- → KH2PO4 & Na2HPO4
- arterial blood: 7.4
- venal blood: 7.3
- tris: 9.3
- electrophoresis
- stable charge to adjust pH (8.6 higher than isoelectric pt, isoelectric pt charge=0 for proteins/amino acids)
- moving boundary (liquid)
- paper-using paper as a medium
- gel-agaros/polyacrylamide
- uses
- protein separated
- DNA/RNA separates different bp length (resolution)
- factors affecting separation
- size-larger for DNA/RNA
- shape
- each kind of protein has the same charge, distribution based on # of nucleotide bases in the fragment, can separate fragments with only 2 base length difference-resolution
- high concentration gives smaller "pores"
- buffers make sure pH of solution stays at 8.6 during electrophoresis
- milk protein: casine
- levels of structure in proteins (4)
- primary: sequence of AA in chain determined by DNA
- secondary: folding of chain into α helical coil, H bonding between C and O atoms (i.e. hair), or β pleated, chain folds back and forth on itself
- tertiary: side chains interacting along same protein
- hydrophobic: turn in (vanderwaals)
- polar: face out, increase solubility
- acid/base: H-bonds, many stop here
- quaternary: different proteins interact (hemoglobin 2α and 2β)
- disulfide bond-cystein
- ionic bond (acid/base)
- shape of protein affected by
- temperature
- pH
- + or - ions in solution
- odd protons: positive
- heavy metals (lead, mercury, cadmium, etc.)
- lead: +2 valence (Ca2+ and Mg2+), brain and spinal cord affected most
- tetraethyl lead (octane)
- cellulose most common organic molecule on earth, about 1 trillion tons made yearly
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