Table 1.

Wild-type and C75S β-glucosidase secreted from Saccharomyces cerevisiae and purified (see Materials and Methods) have similar Michaelis-Menten kinetic parameters. One unit (U) is defined as the amount required to catalyze the formation of 1 mmole p-nitrophenol/min at 90°C. Shown also for comparison are kinetic parameters measured from β-glucosidase recombinantly expressed in E. coli, lacking the c-myc detection tag located on the C-terminus of each monomer a) Smith, J.D., and Robinson, A.S., unpublished data, and β-glucosidase purified directly from Pyrococcus furiosus b) ¹⁵.

	Vmax (U/mg protein)	Km (mM)
wt β-glucosidase a	289	0.34
C75S β-glucosidase (Range based on standard error of fitted parameters)	279 (182-867)	0.54 (0.4-1.4)
β-glucosidase expressed in E. colia	718	0.33
β-glucosidase purified from P. furiosusb	700	0.15