Skip to main content

Advertisement

Table 3 Thermodynamics of lectin/sugar binding. Thermodynamics of binding for different monosaccharides interacting with PA-IIL and its mutants, compared to thermodynamic characteristics of mannose-preferring lectin RS-IIL from Ralstonia solanacearum as determined by ITC at 25°C. Standard deviations calculated from three independent measurements for all ligands.

From: Engineering of PA-IIL lectin from Pseudomonas aeruginosa – Unravelling the role of the specificity loop for sugar preference

  KA [×104M-1] KD [μM] ΔG [kJ/mol] ΔH [kJ/mol] -TΔS [kJ/mol]
Me-α-L-Fuc
G24N 524 (± 36.7) 0.19 (± 0.03) -38.4 (± 0.2) -40.1 (± 0.7) 1.8 (± 0.7)
S23A 418 (± 72.8) 0.25 (± 0.01) -37.8 (± 0.4) -33.9 (± 1.2) -3.8 (± 0.9)
PA-IIL a 235 (± 8.0) 0.43 (± 0.01) -36.4 (± 0.1) -41.3 (± 1.0) 4.9 (± 1.0)
S22A 26.4 (± 4.9) 3.96 (± 0.91) -30.9 (± 0.5) -37.1 (± 0.6) 6.2 (± 0.9)
RS-IILb < 1 > 100    
L-Fuc
S23A 23.8 (± 3.4) 4.3 (± 0.6) -30.6 (± 0.4) -26.9 (± 0.2) -3.7 (± 0.6)
G24N 15.2 (± 2.3) 6.6 (± 0.9) -30.0 (± 0.4) -31.1 (± 0.4) 1.1 (± 0.7)
PA-IIL c 12.0 (± 1.0) 8.3 (± 0.7) -29.0 (± 0.1) -27.7 (± 0.5) -1.3 (± 0.5)
S22A 10.3 (± 0.4) 9.7 (± 0.4) -28.6 (± 0.1) -26.8 (± 0.7) -1.8 (± 0.6)
RS-IIL nd nd nd nd nd
Me-α-L-Gal
PA-IIL a 85.0 (± 5.0) 1.17 (± 0.07) -33.8 (± 0.1) -31.5 (± 0.6) -2.3 (± 0.7)
G24N 82.2 (± 18.8) 1.29 (± 0.35) -33.7 (± 0.6) -18.7 (± 0.3) -15.0 (± 0.9)
S23A 81.6 (± 14.4) 1.23 (± 0.07) -33.9 (± 0.4) -26.8 (± 1.7) 7.1 (± 1.3)
S22A 6.75 (± 0.31) 15.0 (± 0.66) -27.6 (± 0.5) -19.2 (± 0.2) -8.3 (± 0.3)
RS-IIL nd nd nd nd nd
Me-β-D-Man
RS-IIL 438 (± 2.0) 0.23 (± 0.01) -37.9 (± 0.1) -24.9 (± 0.2) -13.0 (± 0.2)
S22A 36.0 (± 1.8) 2.78 (± 0.14) -31.7 (± 0.1) -24.3 (± 0.6) -7.4 (± 0.7)
G24N 2.34 (± 0.17) 42.9 (± 3.12) -24.9 (± 0.2) -27.1 (± 0.8) 2.1 (± 0.9)
S23A 1.91 (± 0.33) 54.0 (± 9.32) -24.4 (± 0.4) -16.7 (± 2.3) -7.7 (± 2.7)
PA-IIL a 1.42 (± 0.05) 71.0 (± 3.00) -23.7 (± 0.1) -17.8 (± 1.3) -5.9 (± 0.3)
  1. a taken from Sabin, C. et al, 2006 [14]
  2. b value < 104 M-1 [18]
  3. c taken from Perret, S. et al, 2005 [11]