Found in these sauces b/c it's very stable and has broad specificity. It will cleave any peptide bond disregarding adjacent side chains. It breaks down connective tissue proteins, which makes meat more tender
Papain helps bc it breaks down symptom-causing toxic proteins in venom that is injected upon a sting. This prevents the protein part of the venom from irritating the body. In mosquito bites, papain helps relieve itch by digesting "itching proteins"
Trypsin cleaves on the carboxyl side of the arginine or lysine residue.
Thrombin cleaves on the carboxyl side of the Arg-Gly bonds (arginine-glycine bonds)
trypsin & thrombin are enzymes that cleave to the right of Arg (and lysine for trypsin)
Trypsin: digestive exzyme, acts in intestine
Thrombin: more specific than trypsin (bc it works in the blood, where there's lots of protein, and can only cleave some)
Activation energy (ΔG‡) doesn't factor in bc the energy added to reach the transition state is released as the transition state becomes the product. Only the diff. in free energy btwn the substrates and product determines equilibrium position of rxn.
Enzymes accelerate rate of rxn by decreasing activation energy (ΔG‡)
Enzymes provide a different transition state (in terms of e‾ energy) with less energy content required for a rxn, thus speeding up rxn to the same degree in both directions.
Part (B) tell us that the active site of a polypeptide chain is composed of residues that come from different parts of the polypeptide chain.
The rest of the molecule creates the shape needed to have contact with substrate. This lysozyme is an exception, w/ a pretty big active site. Its substrate is an polysaccharide, which are easy to cleave bc of weak glycosidic bonds.
van der Waals forces usually contribute significantly to the action of enzymes because of the close proximity of enzyme and substrate
Lysozymes break down the cell walls of some bacteria and help protect the body from bacterial infections
Found in some bodily secretions, like mucus, tears, and saliva, and act defensively at points of entry into body
Transition-state analogs are stable compounds that mimic the unstable transition state of an enzyme reaction
Powerful enzyme inhibitors that provide insight into an enzyme's behavior
"tools" to understand exactly how enzymes work
Pyrrole 2-carboxylic acid is a transition-state analog of the transition
The rxn has a planar transition state, where the tetrahedral alpha carbon becomes trigonal.
The alpha carbon on pyrrole 2-carboxylic acid is also trigonal.
An abzyme is an antibody that can recognize a transition state and thereby function as an enzyme
Humans do not make or use D amino acids, but bacteria do, so this reaction could take place in the bacteria within the body, catalyzed by a bacterial enzyme.
(See original packet)
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