Table 1.

Turnover rates and specific activities on oligosaccharides and pNP-acetate

	kcat [s−1]	Specific activity
Time resolved NMR data on A. vera GGM
RiCE17	4.8
RiCE2 after RiCE17	4.7
RiCE2	1.8
RiCE17 after RiCE2	4.5
Deacetylation of Norway spruce GGM
RiCE17	73.5	1.7
RiCE2	76.7	1.9
RiCE2 + RiCE17	41.7	—
Deacetylation of pNP-acetate
RiCE17	.93
RiCE2	40.00

Turnover rate in time-resolved NMR analysis of deacetylation determined based on the acetate released in the initial 15 min of reaction. Two identical samples of AV mannan hydrolyzed with RiGH26 mannanase were prepared and treated with: 1) 62.5 nM loading of RiCE2 for 16 h, at 298.1 °K, then 10 nM loading of RiCE17; 2) 10 nM loading of RiCE17 for 16 h, then 62.5 nM loading of RiCE2. Turnover rate and specific activity (nanomole acetate/s/µg enzyme) of esterases on Norway spruce GGM RiGH26 hydrolysate were determined based on the amounts of acetate released from samples of 100 mg/mL of substrate in 30 min. Turnover rates of both esterases on pNP-acetate appear lower than on oligosaccharides. Notably, the difference between catalytic activity on AV mannan and Norway spruce GGM cannot be directly compared due to largely different reaction conditions (NMR experiments on AV mannan were run at 298.1 °K/25 °C and pD 5.9 in a 5 mm NMR tube whereas the Norway spruce GGM reactions were run at 30 °C, pH 7.0 and 600 rpm shaking).