Novel properties of molecular assemblies of isoprenoid surfactants

Yamauchi, Kiyoshi; Togawa, Katsuya; Moriya, Tomoaki; Kinoshita, Masayoshi

doi:10.1007/bf00655679

Cited by 3 publications

(1 citation statement)

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“…However, more work is required to determine the likelihood of these and other possible sources of isoprenoids. There has also been relatively little research on the formation of vesicles from isoprenoid SCAs [35,36]. For example, although the addition of isoprenoids to aliphatic hydrocarbon vesicles has been shown to enhance stability in an alkaline hydrothermal fluid analogue [30], the specific aspects of isoprenoid incorporation have not yet been tested.…”

Section: Introductionmentioning

confidence: 99%

Isoprenoids enhance the stability of fatty acid membranes at the emergence of life potentially leading to an early lipid divide

2019

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Two key problems concern cell membranes during the emergence and early evolution of life: what was their initial composition, and why did the membranes of archaea and bacteria diverge? The composition of the first cell membranes could shed light on the most likely environment for the emergence of life. The opposing stereochemistry of modern lipid glycerol-phosphate headgroups in bacteria and archaea suggests that early membranes were composed of single chain amphiphiles, perhaps both fatty acids and isoprenoids. We investigated the effect of adding isoprenoids to fatty acid membranes using a combination of UV–visible spectroscopy, confocal microscopy and transmission electron microscopy. We tested the stability of these membranes across a pH range and under different concentrations of ionic species relevant to oceanic hydrothermal environments, including Na 2+ , Cl − , Mg 2+ , Ca 2+ , HC O 3 − , Fe 3+ , Fe 2+ and S 2− . We also tested the assembly of vesicles in the presence of Fe particles and FeS precipitates. We found that isoprenoids enhance the stability of membranes in the presence of salts but require 30-fold higher concentrations for membrane formation. Intriguingly, isoprenoids strongly inhibit the tendency of vesicles to aggregate together in the presence of either Fe particles or FeS precipitates. These striking physical differences in the stability and aggregation of protocells may have shaped the divergence of bacteria and archaea in early hydrothermal environments.

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Section: Introductionmentioning

confidence: 99%