Table 1. Catalytic parameters of tyrosine-modified and unmodified (control) levansucrase variants using sucrose as a substrate. Catalytic constants reflect the global activity (hydrolysis and transfer).

Enzyme	k cat [s–1]	K M [mM]	k cat/KM [mM s–1]
WT-control	247.8 ± 6.9	21.2 ± 2.7	11.7
WT-2	131.0 ± 5.0	19.2 ± 3.6	6.8
Y247F-control	254.2 ± 3.5	21.9 ± 1.3	11.6
Y247F-2	153.6 ± 3.7	24.5 ± 2.6	6.26
Y247F-2-1AzGlc	172.1 ± 2.8	43.1 ± 2.8	3.9
Y196F-control	285.9 ± 2.8	29.8 ± 1.2	9.6
Y196F-2	173.3 ± 3.4	48.1 ± 3.6	3.6
Y247F/Y196F-control	308.7 ± 6.7	16.7 ± 1.7	18.4
Y247F/Y196F-2	204.9 ± 4.8	17.6 ± 1.9	11.6