Melittin-Phospholipase A2 Synergism Is Mediated by Liquid-Liquid Miscibility Phase Transition in Giant Unilamellar Vesicles

The primary constituents of honeybee venom, melittin and phospholipase A2 (PLA2), display toxin synergism in which the PLA2 activity is significantly enhanced by the presence of melittin. It has been shown previously that this is accomplished by the disruption in lipid packing, which allows PLA2 to become processive on the membrane surface. In this work, we show that melittin is capable of driving miscibility phase transition in giant unilamellar vesicles (GUVs) and that it raises the miscibility transition temperature (Tmisc) in a concentration-dependent manner. The induced phase separation enhances the processivity of PLA2, particularly at its boundaries, where a substantial difference in domain thickness creates a membrane discontinuity. The catalytic action of PLA2, in response, induces changes in the membrane, rendering it more conducive to melittin binding. This, in turn, facilitates further lipid phase separation and eventual vesicle lysis. Overall, our results show that melittin has powerful membrane-altering capabilities that activate PLA2 in various membrane contexts. More broadly, they exemplify how this biochemical system actively modulates and capitalizes on the spatial distribution of membrane lipids to efficiently achieve its objectives.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:40

Enthalten in:

Langmuir : the ACS journal of surfaces and colloids - 40(2024), 14 vom: 09. Apr., Seite 7456-7462

Sprache:

Englisch

Beteiligte Personen:

Min, Sein [VerfasserIn]
Picou, Cyrus [VerfasserIn]
Jeong, Hye Jin [VerfasserIn]
Bower, Adam [VerfasserIn]
Jeong, Keunhong [VerfasserIn]
Chung, Jean K [VerfasserIn]

Links:

Volltext

Themen:

20449-79-0
Bee Venoms
EC 3.1.1.4
Journal Article
Melitten
Membrane Lipids
Phospholipases A2
Unilamellar Liposomes

Anmerkungen:

Date Completed 10.04.2024

Date Revised 10.04.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1021/acs.langmuir.3c03920

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370364082