Multisubstrate analog enzyme

Whenever using alternative substrate inhibition procedures, the investigator must demonstrate that initial rate conditions remain valid throughout the course of the experiment. This is particularly true of the other sub-strate(s) in multisubstrate enzymes. Because both the substrate under study and its analog are present in the reaction mixtures, the other cosubstrates will be depleted faster. This should always be a consideration in the design of the experiment. 

A substrate analog will frequently inhibit only one of the two forms of a multisubstrate enzyme with a ping-pong mechanism.1 72 Reciprocal plots made for various inhibitor concentrations consist of a family of parallel lines reminiscent of uncompetitive inhibition. Observation of such parallel line plots can support a ping-pong mechanism for an enzyme but cannot prove it because in some cases parallel lines are observed for inhibition of enzymes acting by an ordered sequential mechanism. The following question arises naturally for any ordered bimolecular reaction (Eq. 9-43) Of the... 

Analogs For Multisubstrate Reactions - N-(Phosphonacetyl)-L-aspartate (32) incorporates features of both substrates of the enzyme aspartate transcarbamylase (33), although it does not contain a tetrahedral functional group analogous to the tetrahedral-like transition state that is e q>ected for The association constant for binding of... 

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