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Díez Pérez T, Tafoya AN, Peabody DS, Lakin MR, Hurwitz I, Carroll NJ, López GP. Isolation of nucleic acids using liquid-liquid phase separation of pH-sensitive elastin-like polypeptides. Sci Rep 2024; 14:10157. [PMID: 38698072 PMCID: PMC11065875 DOI: 10.1038/s41598-024-60648-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 04/25/2024] [Indexed: 05/05/2024] Open
Abstract
Extraction of nucleic acids (NAs) is critical for many methods in molecular biology and bioanalytical chemistry. NA extraction has been extensively studied and optimized for a wide range of applications and its importance to society has significantly increased. The COVID-19 pandemic highlighted the importance of early and efficient NA testing, for which NA extraction is a critical analytical step prior to the detection by methods like polymerase chain reaction. This study explores simple, new approaches to extraction using engineered smart nanomaterials, namely NA-binding, intrinsically disordered proteins (IDPs), that undergo triggered liquid-liquid phase separation (LLPS). Two types of NA-binding IDPs are studied, both based on genetically engineered elastin-like polypeptides (ELPs), model IDPs that exhibit a lower critical solution temperature in water and can be designed to exhibit LLPS at desired temperatures in a variety of biological solutions. We show that ELP fusion proteins with natural NA-binding domains can be used to extract DNA and RNA from physiologically relevant solutions. We further show that LLPS of pH responsive ELPs that incorporate histidine in their sequences can be used for both binding, extraction and release of NAs from biological solutions, and can be used to detect SARS-CoV-2 RNA in samples from COVID-positive patients.
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Affiliation(s)
- Telmo Díez Pérez
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
- Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM, 87131, USA
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Ashley N Tafoya
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
- Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM, 87131, USA
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
| | - David S Peabody
- Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Matthew R Lakin
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
- Department of Computer Science, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Ivy Hurwitz
- Department of Internal Medicine, Center for Global Health, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Nick J Carroll
- Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM, 87131, USA
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Gabriel P López
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM, 87131, USA.
- Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM, 87131, USA.
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, 87131, USA.
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2
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Jagrosse ML, Baliga UK, Jones CW, Russell JJ, García CI, Najar RA, Rahman A, Dean DA, Nilsson BL. Impact of Peptide Sequence on Functional siRNA Delivery and Gene Knockdown with Cyclic Amphipathic Peptide Delivery Agents. Mol Pharm 2023; 20:6090-6103. [PMID: 37963105 DOI: 10.1021/acs.molpharmaceut.3c00455] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Short-interfering RNA (siRNA) oligonucleotide therapeutics that modify gene expression by accessing RNA-interference (RNAi) pathways have great promise for the treatment of a range of disorders; however, their application in clinical settings has been limited by significant challenges in cellular delivery. Herein, we report a structure-function study using a series of modified cyclic amphipathic cell-penetrating peptides (CAPs) to determine the impact of peptide sequence on (1) siRNA-binding efficiency, (2) cellular delivery and knockdown efficiency, and (3) the endocytic uptake mechanism. Nine cyclic peptides of the general sequence Ac-C[XZ]4CG-NH2 in which X residues are hydrophobic/aromatic (Phe, Tyr, Trp, or Leu) and Z residues are charged/hydrophilic (Arg, Lys, Ser, or Glu) are assessed along with one acyclic peptide, Ac-(WR)4G-NH2. Cyclization is enforced by intramolecular disulfide bond formation between the flanking Cys residues. Binding analyses indicate that strong cationic character and the presence of aromatic residues that are competent to participate in CH-π interactions lead to CAP sequences that most effectively interact with siRNA. CAP-siRNA binding increases in the following order as a function of CAP hydrophobic/aromatic content: His < Phe < Tyr < Trp. Both cationic charge and disulfide-constrained cyclization of CAPs improve uptake of siRNA in vitro. Net neutral CAPs and an acyclic peptide demonstrate less-efficient siRNA translocation compared to the cyclic, cationic CAPs tested. All CAPs tested facilitated efficient siRNA target gene knockdown of at least 50% (as effective as a lipofectamine control), with the best CAPs enabling >80% knockdown. Significantly, gene knockdown efficiency does not strongly correlate with CAP-siRNA internalization efficiency but moderately correlates with CAP-siRNA-binding affinity. Finally, utilization of small-molecule inhibitors and targeted knockdown of essential endocytic pathway proteins indicate that most CAP-siRNA nanoparticles facilitate siRNA delivery through clathrin- and caveolin-mediated endocytosis. These results provide insight into the design principles for CAPs to facilitate siRNA delivery and the mechanisms by which these peptides translocate siRNA into cells. These studies also demonstrate the nature of the relationships between peptide-siRNA binding, cellular delivery of siRNA cargo, and functional gene knockdown. Strong correlations between these properties are not always observed, which illustrates the complexity in the design of optimal next-generation materials for oligonucleotide delivery.
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Affiliation(s)
- Melissa L Jagrosse
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
| | - Uday K Baliga
- Department of Pediatrics and Neonatology, University of Rochester Medical Center, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, United States
| | - Christopher W Jones
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
| | - Jade J Russell
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
| | - Claudia I García
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
| | - Rauf Ahmad Najar
- Department of Pediatrics and Neonatology, University of Rochester Medical Center, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, United States
| | - Arshad Rahman
- Department of Pediatrics and Neonatology, University of Rochester Medical Center, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, United States
| | - David A Dean
- Department of Pediatrics and Neonatology, University of Rochester Medical Center, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, United States
| | - Bradley L Nilsson
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
- Materials Science Program, University of Rochester, Rochester, New York 14627, United States
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3
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Martin C, Bonnet M, Patino N, Azoulay S, Di Giorgio A, Duca M. Design, synthesis and evaluation of neomycin‐imidazole conjugates for RNA cleavage. Chempluschem 2022; 87:e202200250. [DOI: 10.1002/cplu.202200250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/30/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Céline Martin
- Université Côte d'Azur Faculté des Sciences: Universite Cote d'Azur Faculte des Sciences Institut de Chimie de Nice 28 Avenue Valrose 06100 Nice FRANCE
| | - Maurinne Bonnet
- Université Côte d'Azur Faculté des Sciences: Universite Cote d'Azur Faculte des Sciences Institut de Chimie de Nice 28 Avenue Valrose 06100 Nice FRANCE
| | - Nadia Patino
- Université Côte d'Azur Faculté des Sciences: Universite Cote d'Azur Faculte des Sciences Institut de Chimie de Nice 28 Avenue Valrose 06100 Nice FRANCE
| | - Stéphane Azoulay
- Université Côte d'Azur Faculté des Sciences: Universite Cote d'Azur Faculte des Sciences Institut de Chimie de Nice 28 Avenue Valrose 06100 Nice FRANCE
| | - Audrey Di Giorgio
- Université Côte d'Azur Faculté des Sciences: Universite Cote d'Azur Faculte des Sciences Institut de Chimie de Nice 28 Avenue Valrose 06100 Nice FRANCE
| | - Maria Duca
- Institut de Chimie de Nice Université Côte d'Azur Parc Valrose 06100 Nice FRANCE
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Blanco C, Bayas M, Yan F, Chen IA. Analysis of Evolutionarily Independent Protein-RNA Complexes Yields a Criterion to Evaluate the Relevance of Prebiotic Scenarios. Curr Biol 2018; 28:526-537.e5. [PMID: 29398222 DOI: 10.1016/j.cub.2018.01.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/04/2017] [Accepted: 01/03/2018] [Indexed: 12/30/2022]
Abstract
A central difficulty facing study of the origin of life on Earth is evaluating the relevance of different proposed prebiotic scenarios. Perhaps the most established feature of the origin of life was the progression through an RNA World, a prebiotic stage dominated by functional RNA. We use the appearance of proteins in the RNA World to understand the prebiotic milieu and develop a criterion to evaluate proposed synthetic scenarios. Current consensus suggests that the earliest amino acids of the genetic code were anionic or small hydrophobic or polar amino acids. However, the ability to interact with the RNA World would have been a crucial feature of early proteins. To determine which amino acids would be important for the RNA World, we analyze non-biological protein-aptamer complexes in which the RNA or DNA is the result of in vitro evolution. This approach avoids confounding effects of biological context and evolutionary history. We use bioinformatic analysis and molecular dynamics simulations to characterize these complexes. We find that positively charged and aromatic amino acids are over-represented whereas small hydrophobic amino acids are under-represented. Binding enthalpy is found to be primarily electrostatic, with positively charged amino acids contributing cooperatively to binding enthalpy. Arginine dominates all modes of interaction at the interface. These results suggest that proposed prebiotic syntheses must be compatible with cationic amino acids, particularly arginine or a biophysically similar amino acid, in order to be relevant to the invention of protein by the RNA World.
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Affiliation(s)
- Celia Blanco
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106-9510, USA
| | - Marco Bayas
- Departamento de Fisica, Escuela Politécnica Nacional, Quito, Ladron de Guevara E11-253, Ecuador
| | - Fu Yan
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106-9510, USA
| | - Irene A Chen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106-9510, USA; Program in Biomolecular Sciences and Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106-9510, USA.
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5
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Brevet D, Hocine O, Delalande A, Raehm L, Charnay C, Midoux P, Durand JO, Pichon C. Improved gene transfer with histidine-functionalized mesoporous silica nanoparticles. Int J Pharm 2014; 471:197-205. [PMID: 24853464 DOI: 10.1016/j.ijpharm.2014.05.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 05/15/2014] [Accepted: 05/16/2014] [Indexed: 11/19/2022]
Abstract
Mesoporous silica nanoparticles (MSN) were functionalized with aminopropyltriethoxysilane (MSN-NH2) then L-histidine (MSN-His) for pDNA delivery in cells and in vivo. The complexation of pDNA with MSN-NH2 and MSN-His was first studied with gel shift assay. pDNA complexed with MSN-His was better protected from DNase degradation than with MSN-NH2. An improvement of the transfection efficiency in cells was observed with MSN-His/pDNA compared to MSN-NH2/pDNA, which could be explained by a better internalization of MSN-His. The improvement of the transfection efficiency with MSN-His was also observed for gene transfer in Achilles tendons in vivo.
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Affiliation(s)
- David Brevet
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC1701 Equipe Chimie Moléculaire et Organisation du Solide, Place Eugène Bataillon, Cedex 05, Montpellier 34095, France
| | - Ouahiba Hocine
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC1701 Equipe Chimie Moléculaire et Organisation du Solide, Place Eugène Bataillon, Cedex 05, Montpellier 34095, France
| | - Anthony Delalande
- Centre de Biophysique Moléculaire, CNRS-UPR 4301, rue Charles Sadron, Orléans 45071, France
| | - Laurence Raehm
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC1701 Equipe Chimie Moléculaire et Organisation du Solide, Place Eugène Bataillon, Cedex 05, Montpellier 34095, France
| | - Clarence Charnay
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC1701 Equipe Chimie Moléculaire et Organisation du Solide, Place Eugène Bataillon, Cedex 05, Montpellier 34095, France
| | - Patrick Midoux
- Centre de Biophysique Moléculaire, CNRS-UPR 4301, rue Charles Sadron, Orléans 45071, France
| | - Jean-Olivier Durand
- Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC1701 Equipe Chimie Moléculaire et Organisation du Solide, Place Eugène Bataillon, Cedex 05, Montpellier 34095, France.
| | - Chantal Pichon
- Centre de Biophysique Moléculaire, CNRS-UPR 4301, rue Charles Sadron, Orléans 45071, France.
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Zucconi BE, Wilson GM. Assembly of functional ribonucleoprotein complexes by AU-rich element RNA-binding protein 1 (AUF1) requires base-dependent and -independent RNA contacts. J Biol Chem 2013; 288:28034-48. [PMID: 23940053 DOI: 10.1074/jbc.m113.489559] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AU-rich element RNA-binding protein 1 (AUF1) regulates the stability and/or translational efficiency of diverse mRNA targets, including many encoding products controlling the cell cycle, apoptosis, and inflammation by associating with AU-rich elements residing in their 3'-untranslated regions. Previous biochemical studies showed that optimal AUF1 binding requires 33-34 nucleotides with a strong preference for U-rich RNA despite observations that few AUF1-associated cellular mRNAs contain such extended U-rich domains. Using the smallest AUF1 isoform (p37(AUF1)) as a model, we employed fluorescence anisotropy-based approaches to define thermodynamic parameters describing AUF1 ribonucleoprotein (RNP) complex formation across a panel of RNA substrates. These data demonstrated that 15 nucleotides of AU-rich sequence were sufficient to nucleate high affinity p37(AUF1) RNP complexes within a larger RNA context. In particular, p37(AUF1) binding to short AU-rich RNA targets was significantly stabilized by interactions with a 3'-purine residue and largely base-independent but non-ionic contacts 5' of the AU-rich site. RNP stabilization by the upstream RNA domain was associated with an enhanced negative change in heat capacity consistent with conformational changes in protein and/or RNA components, and fluorescence resonance energy transfer-based assays demonstrated that these contacts were required for p37(AUF1) to remodel local RNA structure. Finally, reporter mRNAs containing minimal high affinity p37(AUF1) target sequences associated with AUF1 and were destabilized in a p37(AUF1)-dependent manner in cells. These findings provide a mechanistic explanation for the diverse population of AUF1 target mRNAs but also suggest how AUF1 binding could regulate protein and/or microRNA binding events at adjacent sites.
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Affiliation(s)
- Beth E Zucconi
- From the Department of Biochemistry and Molecular Biology and Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland 21201
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Cruz C, Santos SD, Cabrita EJ, Queiroz JA. Binding analysis between L-histidine immobilized and oligonucleotides by SPR and NMR. Int J Biol Macromol 2013; 56:175-80. [PMID: 23462534 DOI: 10.1016/j.ijbiomac.2013.02.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 02/10/2013] [Accepted: 02/11/2013] [Indexed: 10/27/2022]
Abstract
Saturation transfer difference (STD) NMR technique and surface plasmon resonance (SPR) are used to study amino acid affinity supports-nucleotides interactions with L-histidine amino acid immobilized on a surface as model support. We have immobilized L-histidine ligand on a carboxymethyldextran-modified gold surface intended for surface plasmon resonance and we analyze the binding profiles of synthetic polynucleotides (1-6 base, sugar and backbone) by determining the equilibrium dissociation constant (KD). The SPR binding profile (square-shaped) is identical for all the complexes and the highest binding affinity can be found for polyA₆ followed by polyG₆. As expected, the 5'-mononucleotides have the lowest affinity. To further study the structural aspects of the interaction we investigate the polynucleotide binding preferences to L-histidine chromatography support by STD-NMR spectroscopy. These results revealed that an increase in the number of bases and backbone to 6 units leads to more contacts with the support, where the main driving force for the interaction with polynucleotides are through the base, except for polyC₆, which is mainly through sugar-phosphate backbone. Therefore, the combination of SPR measurements with STD-NMR technique allowed to establish fine details of the molecular recognition process involved in amino acid affinity supports-nucleotides complexes.
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Affiliation(s)
- Carla Cruz
- CICS-UBI - Centro de Investigação em Ciências da Saúde, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
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Lau A, Mays CE, Genovesi S, Westaway D. RGG repeats of PrP-like Shadoo protein bind nucleic acids. Biochemistry 2012; 51:9029-31. [PMID: 23121093 DOI: 10.1021/bi301395w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Shadoo (Sho) is a central nervous system glycoprotein with characteristics similar to those of the cellular prion protein PrP(C), each containing a highly conserved hydrophobic domain (HD) and an N-terminal repeat region. Whereas PrP(C) includes histidine-containing octarepeats, the Sho region N-terminal to the HD includes tandem positively charged "RGG boxes", predicted to bind RNA. Here, we demonstrate that Sho binds DNA and RNA in vitro via this arginine-rich region.
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Affiliation(s)
- Agnes Lau
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2M8, Canada
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9
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Studying salt effects on protein stability using ribonuclease t1 as a model system. Biophys Chem 2011; 161:29-38. [PMID: 22197350 DOI: 10.1016/j.bpc.2011.11.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 11/22/2011] [Accepted: 11/22/2011] [Indexed: 11/21/2022]
Abstract
Salt ions affect protein stability in a variety of ways. In general, these effects have either been interpreted from a charge solvation/charge screening standpoint or they have been considered to be the result of ion-specific interactions with a particular protein. Recent theoretical work suggests that a major contribution to salt effects on proteins is through the interaction of salt ions that are located near the protein surface and their induced point image charges that are located in the low-dielectric protein cavity. These interactions form the basis of "salting-out" interactions. Salt ions induce an image charge of the same sign in the low dielectric protein medium. The interaction between the induced charge and its mirror charge is repulsive and consequently thermodynamically destabilizing. However, a folded protein that has a much smaller surface area will be less destabilized than the unfolded state. Consequently, the folded state will be stabilized relative to the unfolded state. This work analyzes salt effects in the model enzyme ribonuclease t1, and demonstrates that interactions between salt ions and their induced point charges provide a major contribution to the observed salt-induced increase in protein stability. This work also demonstrates that in the case of weakly-binding ions (ions with binding constants that are in the order of 50 M(-1) and less), salting-out effects should still be considered in order to provide a more realistic interpretation of ion binding. These results should therefore be considered when salt effects are used to analyze electrostatic contributions to protein structure or are used to study the thermodynamics of proteins associated with halophillic organisms.
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McDonald GD, Storrie-Lombardi MC. Biochemical constraints in a protobiotic earth devoid of basic amino acids: the "BAA(-) world". ASTROBIOLOGY 2010; 10:989-1000. [PMID: 21162678 DOI: 10.1089/ast.2010.0484] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
It has been hypothesized in this journal and elsewhere, based on surveys of published data from prebiotic synthesis experiments and carbonaceous meteorite analyses, that basic amino acids such as lysine and arginine were not abundant on prebiotic Earth. If the basic amino acids were incorporated only rarely into the first peptides formed in that environment, it is important to understand what protobiotic chemistry is possible in their absence. As an initial test of the hypothesis that basic amino acid negative [BAA(-)] proteins could have performed at least a subset of protobiotic chemistry, the current work reports on a survey of 13 archaeal and 13 bacterial genomes that has identified 61 modern gene sequences coding for known or putative proteins not containing arginine or lysine. Eleven of the sequences found code for proteins whose functions are well known and important in the biochemistry of modern microbial life: lysine biosynthesis protein LysW, arginine cluster proteins, copper ion binding proteins, bacterial flagellar proteins, and PE or PPE family proteins. These data indicate that the lack of basic amino acids does not prevent peptides or proteins from serving useful structural and biochemical functions. However, as would be predicted from fundamental physicochemical principles, we see no fossil evidence of prebiotic BAA(-) peptide sequences capable of interacting directly with nucleic acids.
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Affiliation(s)
- Gene D McDonald
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA.
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