ch 14.5 Flashcards
in a serine protease, what does forming a near attack complex look like
Asp ion “pushes His into a Near attack complex
in a serine protease, what does an acid base reaction look like (similar in other protease mechanisms)
His abstracts H+ from Ser converting Ser into a better (stronger) nucleophile
in protease mechanisms, what is a covalent catalysis
temporary formation of a covalent bond between an enzyme residue AND the substrate (enzyme-substrate complex)
What is a LBHB
low barrier Hydrogen bond that is much stronger than usual hydrogen bond that occurs when H is shared between 2 atoms of similar pKA, WHEN THE NITROGEN HAS A POSITIVE CHARGE
what occurs at the same time as LBHB
quantum tunneling
what is protein motion
movement of a secondary structure at the active site resulting in some change in the substrate such as cisoid to transoid
what is metal catalysis
metal complexed to the active site of the enzyme helping to convert the substrate into a better electrophile and the metal can also stabilize an oxyanion intermediate
what does a pocket of trypsin look like
it is long and narrow with a (-) charge residue at the end as it cleaves K and R which are positive and long
what does a pocket of chymotrypsin look like
pock that is wide to fit the cyclic amino acids that are flat with no charge since they are neutral
in a serine protease, what is the nucleophile
Ser
in a Cysteine protease, what is the nucleophile
Cys
in a Asp protease, what is the nucleophile
H20
in a metallo protease, what is the nucleophile
H20
in a serine protease, is an E/S complex created?
Yes
in a Cysteine protease, is an E/S complex created?
Yes
