Exploring hydrophobic sites in proteins with xenon or krypton.
X-ray diffraction is used to study the binding of xenon and krypton to a variety of crystallised proteins: porcine pancreatic elastase; subtilisin Carlsberg from Bacillus licheniformis; cutinase from Fusarium solani; collagenase from Hypoderma lineatum; hen egg lysozyme, the lipoamide dehydrogenase domain from the outer membrane protein P64k from Neisseria meningitidis; urate-oxidase from Aspergillus flavus, mosquitocidal delta-endotoxin CytB from Bacillus thuringiensis and the ligand-binding domain of the human nuclear retinoid-X receptor RXR-alpha. Under gas pressures ranging from 8 to 20 bar, xenon is able to bind to discrete sites in hydrophobic cavities, ligand and substrate binding pockets, and into the pore of channel-like structures. These xenon complexes can be used to map hydrophobic sites in proteins, or as heavy-atom derivatives in the isomorphous replacement method of structure determination.
Prangé
T
T
LURE, Université Paris-Sud, Orsay, France. prange@lure.u-psud.fr
Schiltz
M
M
Pernot
L
L
Colloc'h
N
N
Longhi
S
S
Bourguet
W
W
Fourme
R
R
D000818:Animals; D006801:Humans; D007726:Krypton; D011506:Proteins / Q000737:chemistry*; D014978:Xenon
D011506:Proteins; D014978:Xenon; D007726:Krypton