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Table 3 Activity profile of the active glycoside hydrolase enzymes

From: Discovery and characterization of ionic liquid-tolerant thermophilic cellulases from a switchgrass-adapted microbial community

Gene ID 01 02 03 05 06 07 08 09 11 14 15 16 17 18 19 24 25 26 29 30 36
T opt (°C) 45 90 75 70 65 70 90 90 60 70 70 80 60 95 80 55 95 95 65 50 95
Temp (°C) ≥80% activity 45–50 80–90 75 60–75 55–70 65–70 80–90 80–90 55–60 60–75 65–70 75–80 55–60 85–95 70–85 50–60 80–95 85–95 55–70 45–55 75–95
Temp (°C) ≥50% activity 45–55 70–90 70–80 45–80 45–75 60–75 65–90 65–90 45–65 50–75 60–70 70–80 45–60 70–95 60–85 45–65 60–95 75–95 50–70 45–55 55–95
pH opt 6 7 5.5 7 6 6 5 5 6 6 6.5 5 6 6 5.5 6.5 7.5 7.5 7.5 6 6
pH ≥80% activity 6–6.5 5.5–8 4.5–6 6–7.5 5–6.5 6–7.5 4–8 4–8 5–6.5 5.5–7.5 6–7 5–5.5 5 –7 4.5–7 4.5–7.5 5.5–7.5 4–8 5.5–8 5.5–8 5–7 6–7.5
pH ≥50% activity 5–7 4.5–8 4.5–7 5.5–8 4.5–7.5 5.5–8 4–8 4–8 4.5–7 5–8 6–7.5 5–6.5 5–7.5 4–8 4.5–8 5–8 4–8 4–8 5–8 4.5–8 5.5–8
IL% (v/v) ≥100% activity 0 15 40 35 5 10 0 0 10 5 0 35 0 5 10 10 40 30 5 25 35
IL% (v/v) ≥80% activity 0 25 40 40 5 15 5 5 15 10 0 40 0 15 20 10 40 35 10 30 35
IL% (v/v) ≥50% activity 15 35 40 40 5 15 20 20 20 20 0 40 5 30 30 15 40 35 15 35 35
Max activity in IL* 0.68 (5) 1.1 (5) 1.2 (40) 2.1 (15) 1.3 (5) 1.2 (5) 0.87 (5) 0.89 (5) 1.5 (5) 1.2 (5) 0.45 (5) 5 (10) 0.5 (5) 1.2 (5) 1.1 (5) 2.1 (5) 1.9 (15) 2.5 (15) 1.4 (5) 2.5 (15) 2 (25)
  1. Enzyme activity was profiled at temperatures between 45 and 95°C, pH between 4 and 8, and IL concentrations between 0 and 40% (v/v) of [C2mim][OAc]. The temperature and pH that elicited the highest activity is indicated in row Topt and pHopt, respectively. Temperature and pH ranges that permitted greater than 80% and 50% activity are indicated below the optimum value. IL-tolerance is indicated as the maximum concentration of [C2mim][OAc] that permits at least 80% and 50% enzyme activity (i.e. a value of 15 in the 80% row would indicate that 15% (v/v) of [C2mim][OAc] is the maximum concentration of [C2mim][OAc] that can be used to retain at least 80% enzyme activity). Most enzymes showed a steady decline in activity with increasing IL concentrations. *Max activity in IL is reported as the highest fold change of activity in the presence of IL compared to water and the () indicates the IL concentration (v/v) in which that highest activity as achieved. Values less than 1 indicate the enzyme is less active in IL than in water while values greater than 1 indicate the enzyme has increased activity in the presence of IL.