The lower activity of S146A was due to a combination of increased Km and decreased kcat.
Significantly increased Vmax for alanine (p = 0.014) and increased Km for tyrosine (p = 0.007) were found in children with autism.
Mutations at aspartate 103 resulted in enzymes that were greatly affected for different kinetic parameters, including an increased Km for CO2.
Removing functionality at either of these positions alters the enzyme's ability to effectively utilize homoserine or succinyl-CoA, respectively, reflected in an increased Km and decreased catalytic efficiency.
A purely unphosphorylated isoform of His6-PDK1 (pI = 6.8) was generated by treatment with lambda protein phosphatase (λPP), which decreased Vmax to 2.4 ± 0.4 U/mg and increased Km (PDK-Tide) to 217 ± 61 μM.
Deleterious mutations made up the majority of the dataset and also contained the greatest number of keywords: decrease, inhibit, reduc, loss, lower, abolish, abrogate, inactive, diminish, disrupt, impair, eliminate, no activity, prevent, suppress, increases km, increases the km.
In that protein, H230A had little effect on function, while H230K had only half of the normal transport activity, and an increased Km for Na+ ions.
The recognition for the natural dGTP substrate was only modestly affected by ETVr changes, which increased Km values 2.2- to 2.6-fold (Table 2).
When Gln28 was mutated to alanine in Q28A variant there was a 5-fold reduction in the catalytic efficiency (kcat/Km) as compared to that of HPR, which was mainly due to an increased Km.
These results suggest that the presence of gT at the 3'-terminus of the primer may interfere with essential conformational changes of the enzyme during its catalytic cycle, resulting in both slower kcat and increased Km values.
