Table III.

Kinetic parameters for various 2-oxo acids with recombinant MAM3a

SubstrateKmVmaxkcatkcat/Km
μmnmol min−1mg−1s−1m−1s−1
4-Methylthio-2-oxobutanoic acid (→C3 glucosinolates)932 ± 561,448 ± 2991.3 ± 0.31,380
5-Methylthio-2-oxopentanoic acid (→C4 glucosinolates)476 ± 1991,495 ± 6791.3 ± 0.62,730
6-Methylthio-2-oxohexanoic acid (→C5 glucosinolates)463 ± 2102,869 ± 7682.5 ± 0.75,400
8-Methylthio-2-oxooctanoic acid (→C7 glucosinolates)253 ± 123364 ± 1430.3 ± 0.11,280
9-Methylthio-2-oxononanoic acid (→C8 glucosinolates)81 ± 2131 ± 80.03 ± 0.01370
2-Oxoisovalerate1,000 ± 200199 ± 380.18 ± 0.03200
Pyruvate8,600 ± 4,300191 ± 480.17 ± 0.0423
Acetyl-CoA2,300 ± 1,2003,344 ± 14283.0 ± 1.31,300
  • a Data presented are means ± sds of at least five replicates per substrate.