51
|
Izgu EC, Björkbom A, Kamat NP, Lelyveld VS, Zhang W, Jia TZ, Szostak JW. N-Carboxyanhydride-Mediated Fatty Acylation of Amino Acids and Peptides for Functionalization of Protocell Membranes. J Am Chem Soc 2016; 138:16669-16676. [PMID: 27959544 PMCID: PMC7547885 DOI: 10.1021/jacs.6b08801] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Early protocells are likely to have arisen from the self-assembly of RNA, peptide, and lipid molecules that were generated and concentrated within geologically favorable environments on the early Earth. The reactivity of these components in a prebiotic environment that supplied sources of chemical energy could have produced additional species with properties favorable to the emergence of protocells. The geochemically plausible activation of amino acids by carbonyl sulfide has been shown to generate short peptides via the formation of cyclic amino acid N-carboxyanhydrides (NCAs). Here, we show that the polymerization of valine-NCA in the presence of fatty acids yields acylated amino acids and peptides via a mixed anhydride intermediate. Notably, Nα-oleoylarginine, a product of the reaction between arginine and oleic acid in the presence of valine-NCA, partitions spontaneously into vesicle membranes and mediates the association of RNA with the vesicles. Our results suggest a potential mechanism by which activated amino acids could diversify the chemical functionality of fatty acid membranes and colocalize RNA with vesicles during the formation of early protocells.
Collapse
Affiliation(s)
- Enver Cagri Izgu
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Anders Björkbom
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.,Department of Biosciences, Åbo Akademi University , Åbo FI-20520, Finland
| | - Neha P Kamat
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Victor S Lelyveld
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States
| | - Weicheng Zhang
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.,Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Tony Z Jia
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.,Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital , 185 Cambridge Street, Boston, Massachusetts 02114, United States.,Department of Genetics, Harvard Medical School , 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.,Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| |
Collapse
|
52
|
Black RA, Blosser MC. A Self-Assembled Aggregate Composed of a Fatty Acid Membrane and the Building Blocks of Biological Polymers Provides a First Step in the Emergence of Protocells. Life (Basel) 2016; 6:E33. [PMID: 27529283 PMCID: PMC5041009 DOI: 10.3390/life6030033] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/02/2016] [Accepted: 08/09/2016] [Indexed: 02/01/2023] Open
Abstract
We propose that the first step in the origin of cellular life on Earth was the self-assembly of fatty acids with the building blocks of RNA and protein, resulting in a stable aggregate. This scheme provides explanations for the selection and concentration of the prebiotic components of cells; the stabilization and growth of early membranes; the catalysis of biopolymer synthesis; and the co-localization of membranes, RNA and protein. In this article, we review the evidence and rationale for the formation of the proposed aggregate: (i) the well-established phenomenon of self-assembly of fatty acids to form vesicles; (ii) our published evidence that nucleobases and sugars bind to and stabilize such vesicles; and (iii) the reasons why amino acids likely do so as well. We then explain how the conformational constraints and altered chemical environment due to binding of the components to the membrane could facilitate the formation of nucleosides, oligonucleotides and peptides. We conclude by discussing how the resulting oligomers, even if short and random, could have increased vesicle stability and growth more than their building blocks did, and how competition among these vesicles could have led to longer polymers with complex functions.
Collapse
Affiliation(s)
- Roy A Black
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.
| | | |
Collapse
|