Dear All,
Sorry for the non-ccp4 query.
I have solved a crystal structure of an enzyme and woring on its biochemical
aspect. We have a mutant of this enzyme and we are comparing some
thermodynamic parameters of this enzyme with mutant( lke delH and delS,
delG). we have done the expt at different
James-
It's:
lnKd = deltaH- RT(deltaS)
As for Km ~ Kd, here be dragons...Km values cannot be treated as the Kd of a
complex because dissociation of a catalytic complex has two potential fates,
one that is denoted by a rate constant that is correlated to turnover (so,
the forward reaction leading
Km is the amount of substrate needed to get the enzyme to half-maximum
velocity. So if the brain enzyme needs 10 times less substrate to reach
half-maximum velocity, you would see the apparent Km go down from 25, not up.
Any undergrad biochemistry text will have all this stuff in it.
Or am I
This is absolutely correct. For many enzymes, Km
is a conflation of many rate constants in the chemical mechanism. You
would have to know for certain, based on prior mechanistic work, that
all steps subsequent to substrate binding are slow enough for the
experimentally measured Km to
James,
I think you need to be a little more specific about what you want to
calculate. Keq for a reaction A = B will not change with an enzyme
mutation as the thermodynamic relationships between the reactants and
products do not change. As a catalyst, the enzyme impacts only the
free
