TABLE 3.

Kinetic analysis of DsbB mutantsa

EnzymeKm (DsbA)Km (Q)kcat
WT3.513.7
Q33A4052.7
Y46F181.84.2
R48K6.21.10.9
R48H3.37.11.6
H91A8.81.70.68
Q95A6.5169
  • a Kinetic analysis was performed as described in Materials and Methods with reduced purified DsbA and dodecyl quinone (Q) as two substrates. Values of apparent Km are in micromolar; kcat is in nanomoles of DsbA/nanomole of DsbB/second. Wild type (WT) refers to WM76, the wild-type DsbB with C8A and C49V substitutions. Results shown in bold are significantly different from that of the wild type. No significant activity was detected for R48A and L43P. R48H values are quoted from reference 21.