A novel type of artificial cell-surface receptor capable of affecting enzym
ic activity was designed by employing steroidal moiety. Bile acid derivativ
es having an amino group, effectively recognized both the aromatic aldehyde
s and copper(II) ions in bilayer membrane formed with a synthetic peptide l
ipid. On the other hand, pig heart L-lactate dehydrogenase (LDH) was bound
to the bilayer membrane surface mainly through electrostatic interactions,
and the LDH activity was specifically inhibited by copper(LI) ions. On thes
e grounds, we constituted artificial signaling systems in combinations, wit
h a steroidal receptor, a bilayer-forming synthetic lipid, and LDH. The pre
sent supramolecular vesicles acted as nano-reactors in which the artificial
receptor was able to switch on the enzymic activity via accompanying doubl
e signal recognition and phase reorganization (C) 2001 Elsevier Science B.V
. All rights reserved.