Molecular recognition of concanavalin A on mannoside diacetylene lipid monolayer at the air-water interface.
The interaction of p-10,12-pentacosadiyne-1-n-phenylamide alpha-D-mannopyranoside (MPDA) with protein concanavalin A (Con A) was studied at the air/water interface. The expansion of molecular area of PDA (10,12-pentacosadiynoic acid)/MPDA mixed monolayer after injection of Con A in subphase shows strong interaction between Con A and the monolayer. The maximum expansion of molecular area decreases as the molar ratio of MPDA increases due to the steric hindrance effect. By using enzyme mannosidase to cut-off the mannoside headgroup of MPDA, expansion of molecular area was greatly reduced, indicating that the binding of Con A is specific to the mannoside headgroup. The kinetics of the binding fits to the first order bimolecular reaction model. Fluorescence quenching of fluorescein isothiocyanate labeled Con A after injection into the subphase gives a direct proof of the molecular recognition.
Center for Supramolecular Science and Department of Chemistry, University of Miami, Coral Gables, FL 33124, USA.
S
S
Wang
R M
RM
Leblanc
D000388:Air; D015374:Biosensing Techniques; D003208:Concanavalin A / Q000737:chemistry*; D016650:Fluorescein-5-isothiocyanate; D008358:Mannose / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry; D008362:Mannosides / Q000737:chemistry*; D008563:Membrane Lipids / Q000737:chemistry*; D011956:Receptors, Cell Surface / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014867:Water
D008362:Mannosides; D008563:Membrane Lipids; D011956:Receptors, Cell Surface; C120855:p-10,12-pentacosadiyne-1-n-phenylamide-mannopyranoside; D014867:Water; D003208:Concanavalin A; D016650:Fluorescein-5-isothiocyanate; D008358:Mannose