Autocatalytic self-replicating micelles as models for prebiotic structures

• Published in: Nature (London) 1992-05, Vol.357 (6373), p.57-59
• Main Authors: Bachmann, Pascale Angelica, Luisi, Pier Luigi, Lang, Jacques
• Format: Article
• Language: English
• Subjects: alkaline; Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Humanities and Social Sciences; Hydrolysis; letter; micelles; Micelles. Thin films; Molecules; multidisciplinary; Science; Science (multidisciplinary); structure
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/357057a0

MICELLES that can catalyse their replication have been described recently 1–3 . In the previous experiments, micelles (or bilayer vesicles 4 ) were always present in the initial reaction mixture—that is, the system was presented with the bounded structures required for autocatalysis. Here we describe a system in which autocatalytic micelles are formed from amphiphiles that are themselves generated from a hydrolysis reaction in the absence of compartmental structures. Alkaline hydrolysis of ethyl caprylate (itself insoluble in water) yields sodium caprylate, initially at a very slow rate; but as soon as sufficient caprylate is formed for aggregation into micelles to take place, there is an exponential increase in reaction rate owing to micellar catalysis. These self-assembling surfactant structures may consequently provide a model system for studies of prebiotic chemistry. The possible relevance of this process to prebiotic chemistry is emphasized by our observation that the micelles can be converted into more-robust vesicles by a pH change induced by dissolved CO 2 .