Optimization of xenon biosensors for detection of protein interactions.
Hyperpolarized 129Xe NMR spectroscopy can detect the presence of specific low-concentration biomolecular analytes by means of a xenon biosensor that consists of a water-soluble, targeted cryptophane-A cage that encapsulates the xenon. In this work, we use the prototypical biotinylated xenon biosensor to determine the relationship between the molecular composition of the xenon biosensor and the characteristics of protein-bound resonances. The effects of diastereomer overlap, dipole-dipole coupling, chemical-shift anisotropy, xenon exchange, and biosensor conformational exchange on the protein-bound biosensor signal were assessed. It was found that an optimal protein-bound biosensor signal can be obtained by minimizing the number of biosensor diastereomers and using a flexible linker of appropriate length. Both the line width and sensitivity of chemical shift to protein binding of the xenon biosensor were found to be inversely proportional to linker length.
Lowery
Thomas J
TJ
Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA.
Garcia
Sandra
S
Chavez
Lana
L
Ruiz
E Janette
EJ
Wu
Tom
T
Brotin
Thierry
T
Dutasta
Jean-Pierre
JP
King
David S
DS
Schultz
Peter G
PG
Pines
Alex
A
Wemmer
David E
DE
D001360:Avidin / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods* / Q000592:standards; D003903:Deuterium; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008958:Models, Molecular; D015394:Molecular Structure; D011485:Protein Binding; D011487:Protein Conformation; D012015:Reference Standards; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014978:Xenon / Q000737:chemistry*; D014979:Xenon Isotopes
D014979:Xenon Isotopes; D001360:Avidin; D014978:Xenon; D003903:Deuterium