Schiff Base in Enzyme Mechanisms

Question

Can a schiff base stabilize the transition state and form an intermediate as in covalent catalysis with a substrate in the same reaction? Basically I'm wondering if a schiff base creates a ping pong reaction.

Answer 1

I think the answer to this one is a most definite 'yes'. Almost all aminotransferases proceed via a ping-pong mechanism where a schiff base involving pyridoxal phosphate is an obligate intermediate, and where the 'half-reation' modified enzyme form has often been isolated. An example is aspartate aminotransferase.

Let's also remind ourselves that a transition state is not an intermediate on the reaction pathway (in the TS bonds are in the process of being broken and formed), but may resemble one.