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What are the Kcat,Km,Kcat/Km enzymology values? - (Mar/15/2019 )


Can someone explain in simple terms the enzymology values of kcat, km and kcat/km?

From what I gathered all mean how many substrate molecules are converted by an enzyme molecule per unit of time, is this correct? (let's say the conversion rate)

The kcat is the conversion rate when there is maximum substrate concentration that saturate the enzyme.
The km is the conversion rate when there is half of the saturation concentration of the substrate.
the kcat/km is the conversion rate when there is minimum substrate concentration.

Are these accurate? What do we mean by minimum substrate concentration? How can I find the exact conversion rate when I know the kcat/km and the substrate concentration of my solution?



km is the substrate concentration at 1/2 vmax, not necessarily 1/2 substrate saturation.


look at this wikipedia entry on enzyme kinetics.