title: Ca2+-independent interaction of annexin I with phospholipid monolayers.
abstract: At pH 6.0, the interaction of annexin I, a proteolytic fragment of annexin I and annexin V, was studied with monolayers composed of dipalmitoylphosphatidylserine (DPPS), dipalmitoylphosphatidylcholine (DPPC) or DPPS/DPPC mixtures (molar ratio 1:4). The measurements reveal that only annexin I shows a significant increase in the surface pressure at constant surface area in the absence of Ca2+ ions. We interpret these pressure changes as reflecting penetration of the protein. Kinetic analyses of the annexin I/monolayer interaction at pH 6.0 in the presence and absence of Ca2+ ions show differences between the interaction mechanisms that support the occurrence of a pH-regulated process. At pH 7.4, Ca2+ ions are required for the interaction.
authors.affiliation: Institut für Medizinische Biochemie, Münster, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Rosengarth
authors.forename: A
authors.initials: A
authors.lastname: Wintergalen
authors.forename: H J
authors.initials: HJ
authors.lastname: Galla
authors.forename: H J
authors.initials: HJ
authors.lastname: Hinz
authors.forename: V
authors.initials: V
authors.lastname: Gerke
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D000818:Animals; D017305:Annexin A1 / Q000737:chemistry* / Q000378:metabolism; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D008081:Liposomes / Q000737:chemistry*; D010718:Phosphatidylserines / Q000737:chemistry*; D011312:Pressure; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013499:Surface Properties; D013552:Swine
chemical_list: D017305:Annexin A1; D008081:Liposomes; D010718:Phosphatidylserines; D011994:Recombinant Proteins; D015060:1,2-Dipalmitoylphosphatidylcholine; C038694:dipalmitoylphosphatidylserine; D002118:Calcium