Introduction to Enzyme and Coenzyme Chemistry - E-Library Home

54 Chapter 4
Figure 4.3 PuriWcation of 2-hydroxypentadienoic acid hydratase from Escherichia coli. The photo
shows an SDS-polyacrylamide gel of samples taken from the puriWcation of this enzyme. Lane 1, E.
coli crude extract; lane 2, DEAE sephadex pool; lane 3, phenyl agarose pool; lane 4, monoQ anionexchange
pool; lane 5, molecular weight standards (2 98 kDa, 66 kDa, 43 kDa, 29 kDa, 21 kDa).
(see also Table 4.1).
calculated from the speciWc activity of the pure enzyme (in units per mg of
protein) and the molecular weight of the enzyme (see Problem 1). The isolation
of pure enzyme also allows active site studies to be carried out on the homogeneous
protein, and crystallisation of the enzyme for X-ray crystallographic
analysis.
4.3 Enzyme kinetics
It is possible to learn a great deal about how an enzyme works from a detailed
kinetic study of the enzymatic reaction. For the purposes of this chapter I will
give only a brief discussion of a simple model of enzyme kinetics; a full discussion
of enzyme kinetics is given in texts such as Segel (see Further reading).