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Coupled phases and combinatorial selection in fluctuating hydrothermal pools: a scenario to guide experimental approaches to the origin of cellular life.

Damer B, Deamer D - Life (Basel) (2015)

Bottom Line: Two kinds of selective processes can then occur.The second is a chemical process in which rare combinations of encapsulated polymers form systems capable of capturing energy and nutrients to undergo growth by catalyzed polymerization.Given continued cycling over extended time spans, such combinatorial processes will give rise to molecular systems having the fundamental properties of life.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomolecular Engineering. bdamer@ucsc.edu.

ABSTRACT
Hydrothermal fields on the prebiotic Earth are candidate environments for biogenesis. We propose a model in which molecular systems driven by cycles of hydration and dehydration in such sites undergo chemical evolution in dehydrated films on mineral surfaces followed by encapsulation and combinatorial selection in a hydrated bulk phase. The dehydrated phase can consist of concentrated eutectic mixtures or multilamellar liquid crystalline matrices. Both conditions organize and concentrate potential monomers and thereby promote polymerization reactions that are driven by reduced water activity in the dehydrated phase. In the case of multilamellar lipid matrices, polymers that have been synthesized are captured in lipid vesicles upon rehydration to produce a variety of molecular systems. Each vesicle represents a protocell, an "experiment" in a natural version of combinatorial chemistry. Two kinds of selective processes can then occur. The first is a physical process in which relatively stable molecular systems will be preferentially selected. The second is a chemical process in which rare combinations of encapsulated polymers form systems capable of capturing energy and nutrients to undergo growth by catalyzed polymerization. Given continued cycling over extended time spans, such combinatorial processes will give rise to molecular systems having the fundamental properties of life.

No MeSH data available.


Related in: MedlinePlus

A multilamellar matrix forms again during dehydration.
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life-05-00872-f007: A multilamellar matrix forms again during dehydration.

Mentions: In the next dehydration cycle (Figure 7), the surviving protocells aggregate on the mineral surface and fuse again with the multilamellar matrix. During this process, the encapsulated contents mix and distribute stabilizing polymers into the next generation of protocells. We term this a coupling of the contents of the protocells between the two phases. In other words, two phases of a naturally recurring process—hydration and dehydration—lead to an initial synthesis of a polymer in an anhydrous phase followed by selection of encapsulated polymers in a hydrated phase. The coupled cycles occur indefinitely, thereby allowing accumulation of increasingly complex systems of polymers.


Coupled phases and combinatorial selection in fluctuating hydrothermal pools: a scenario to guide experimental approaches to the origin of cellular life.

Damer B, Deamer D - Life (Basel) (2015)

A multilamellar matrix forms again during dehydration.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390883&req=5

life-05-00872-f007: A multilamellar matrix forms again during dehydration.
Mentions: In the next dehydration cycle (Figure 7), the surviving protocells aggregate on the mineral surface and fuse again with the multilamellar matrix. During this process, the encapsulated contents mix and distribute stabilizing polymers into the next generation of protocells. We term this a coupling of the contents of the protocells between the two phases. In other words, two phases of a naturally recurring process—hydration and dehydration—lead to an initial synthesis of a polymer in an anhydrous phase followed by selection of encapsulated polymers in a hydrated phase. The coupled cycles occur indefinitely, thereby allowing accumulation of increasingly complex systems of polymers.

Bottom Line: Two kinds of selective processes can then occur.The second is a chemical process in which rare combinations of encapsulated polymers form systems capable of capturing energy and nutrients to undergo growth by catalyzed polymerization.Given continued cycling over extended time spans, such combinatorial processes will give rise to molecular systems having the fundamental properties of life.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomolecular Engineering. bdamer@ucsc.edu.

ABSTRACT
Hydrothermal fields on the prebiotic Earth are candidate environments for biogenesis. We propose a model in which molecular systems driven by cycles of hydration and dehydration in such sites undergo chemical evolution in dehydrated films on mineral surfaces followed by encapsulation and combinatorial selection in a hydrated bulk phase. The dehydrated phase can consist of concentrated eutectic mixtures or multilamellar liquid crystalline matrices. Both conditions organize and concentrate potential monomers and thereby promote polymerization reactions that are driven by reduced water activity in the dehydrated phase. In the case of multilamellar lipid matrices, polymers that have been synthesized are captured in lipid vesicles upon rehydration to produce a variety of molecular systems. Each vesicle represents a protocell, an "experiment" in a natural version of combinatorial chemistry. Two kinds of selective processes can then occur. The first is a physical process in which relatively stable molecular systems will be preferentially selected. The second is a chemical process in which rare combinations of encapsulated polymers form systems capable of capturing energy and nutrients to undergo growth by catalyzed polymerization. Given continued cycling over extended time spans, such combinatorial processes will give rise to molecular systems having the fundamental properties of life.

No MeSH data available.


Related in: MedlinePlus