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Qiu Z, Huang R, Wu Y, Li X, Sun C, Ma Y. Decoding the Structural Diversity: A New Horizon in Antimicrobial Prospecting and Mechanistic Investigation. Microb Drug Resist 2024; 30:254-272. [PMID: 38648550 DOI: 10.1089/mdr.2023.0232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
The escalating crisis of antimicrobial resistance (AMR) underscores the urgent need for novel antimicrobials. One promising strategy is the exploration of structural diversity, as diverse structures can lead to diverse biological activities and mechanisms of action. This review delves into the role of structural diversity in antimicrobial discovery, highlighting its influence on factors such as target selectivity, binding affinity, pharmacokinetic properties, and the ability to overcome resistance mechanisms. We discuss various approaches for exploring structural diversity, including combinatorial chemistry, diversity-oriented synthesis, and natural product screening, and provide an overview of the common mechanisms of action of antimicrobials. We also describe techniques for investigating these mechanisms, such as genomics, proteomics, and structural biology. Despite significant progress, several challenges remain, including the synthesis of diverse compound libraries, the identification of active compounds, the elucidation of complex mechanisms of action, the emergence of AMR, and the translation of laboratory discoveries to clinical applications. However, emerging trends and technologies, such as artificial intelligence, high-throughput screening, next-generation sequencing, and open-source drug discovery, offer new avenues to overcome these challenges. Looking ahead, we envisage an exciting future for structural diversity-oriented antimicrobial discovery, with opportunities for expanding the chemical space, harnessing the power of nature, deepening our understanding of mechanisms of action, and moving toward personalized medicine and collaborative drug discovery. As we face the continued challenge of AMR, the exploration of structural diversity will be crucial in our search for new and effective antimicrobials.
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Affiliation(s)
- Ziying Qiu
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Rongkun Huang
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Yuxuan Wu
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Xinghao Li
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Chunyu Sun
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Yunqi Ma
- School of Pharmacy, Binzhou Medical University, Yantai, China
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Colón-Santos S, Vázquez-Salazar A, Adams A, Campillo-Balderas JA, Hernández-Morales R, Jácome R, Muñoz-Velasco I, Rodriguez LE, Schaible MJ, Schaible GA, Szeinbaum N, Thweatt JL, Trubl G. Chapter 2: What Is Life? ASTROBIOLOGY 2024; 24:S40-S56. [PMID: 38498820 DOI: 10.1089/ast.2021.0116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The question "What is life?" has existed since the beginning of recorded history. However, the scientific and philosophical contexts of this question have changed and been refined as advancements in technology have revealed both fine details and broad connections in the network of life on Earth. Understanding the framework of the question "What is life?" is central to formulating other questions such as "Where else could life be?" and "How do we search for life elsewhere?" While many of these questions are addressed throughout the Astrobiology Primer 3.0, this chapter gives historical context for defining life, highlights conceptual characteristics shared by all life on Earth as well as key features used to describe it, discusses why it matters for astrobiology, and explores both challenges and opportunities for finding an informative operational definition.
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Affiliation(s)
- Stephanie Colón-Santos
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Wisconsin, USA
- Department of Botany, University of Wisconsin-Madison, Wisconsin, USA
| | - Alberto Vázquez-Salazar
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Department of Chemical and Biomolecular Engineering, University of California Los Angeles, California, USA
| | - Alyssa Adams
- Department of Botany, University of Wisconsin-Madison, Wisconsin, USA
| | | | - Ricardo Hernández-Morales
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Rodrigo Jácome
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Israel Muñoz-Velasco
- Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Laura E Rodriguez
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
- Lunar and Planetary Institute, Universities Space Research Association, Houston, Texas, USA
| | - Micah J Schaible
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - George A Schaible
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Nadia Szeinbaum
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Jennifer L Thweatt
- Department of Biochemistry and Molecular Biology, Penn State University, University Park, Pennsylvania, USA. (Former)
| | - Gareth Trubl
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
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Tirumalai MR, Sivaraman RV, Kutty LA, Song EL, Fox GE. Ribosomal Protein Cluster Organization in Asgard Archaea. ARCHAEA (VANCOUVER, B.C.) 2023; 2023:5512414. [PMID: 38314098 PMCID: PMC10833476 DOI: 10.1155/2023/5512414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/31/2023] [Accepted: 09/08/2023] [Indexed: 02/06/2024]
Abstract
It has been proposed that the superphylum of Asgard Archaea may represent a historical link between the Archaea and Eukarya. Following the discovery of the Archaea, it was soon appreciated that archaeal ribosomes were more similar to those of Eukarya rather than Bacteria. Coupled with other eukaryotic-like features, it has been suggested that the Asgard Archaea may be directly linked to eukaryotes. However, the genomes of Bacteria and non-Asgard Archaea generally organize ribosome-related genes into clusters that likely function as operons. In contrast, eukaryotes typically do not employ an operon strategy. To gain further insight into conservation of the r-protein genes, the genome order of conserved ribosomal protein (r-protein) coding genes was identified in 17 Asgard genomes (thirteen complete genomes and four genomes with less than 20 contigs) and compared with those found previously in non-Asgard archaeal and bacterial genomes. A universal core of two clusters of 14 and 4 cooccurring r-proteins, respectively, was identified in both the Asgard and non-Asgard Archaea. The equivalent genes in the E. coli version of the cluster are found in the S10 and spc operons. The large cluster of 14 r-protein genes (uS19-uL22-uS3-uL29-uS17 from the S10 operon and uL14-uL24-uL5-uS14-uS8-uL6-uL18-uS5-uL30-uL15 from the spc operon) occurs as a complete set in the genomes of thirteen Asgard genomes (five Lokiarchaeotes, three Heimdallarchaeotes, one Odinarchaeote, and four Thorarchaeotes). Four less conserved clusters with partial bacterial equivalents were found in the Asgard. These were the L30e (str operon in Bacteria) cluster, the L18e (alpha operon in Bacteria) cluster, the S24e-S27ae-rpoE1 cluster, and the L31e, L12..L1 cluster. Finally, a new cluster referred to as L7ae was identified. In many cases, r-protein gene clusters/operons are less conserved in their organization in the Asgard group than in other Archaea. If this is generally true for nonribosomal gene clusters, the results may have implications for the history of genome organization. In particular, there may have been an early transition to or from the operon approach to genome organization. Other nonribosomal cellular features may support different relationships. For this reason, it may be important to consider ribosome features separately.
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Affiliation(s)
- Madhan R. Tirumalai
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA
| | | | | | | | - George E. Fox
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA
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Zachar I, Boza G. The Evolution of Microbial Facilitation: Sociogenesis, Symbiogenesis, and Transition in Individuality. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.798045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Metabolic cooperation is widespread, and it seems to be a ubiquitous and easily evolvable interaction in the microbial domain. Mutual metabolic cooperation, like syntrophy, is thought to have a crucial role in stabilizing interactions and communities, for example biofilms. Furthermore, cooperation is expected to feed back positively to the community under higher-level selection. In certain cases, cooperation can lead to a transition in individuality, when freely reproducing, unrelated entities (genes, microbes, etc.) irreversibly integrate to form a new evolutionary unit. The textbook example is endosymbiosis, prevalent among eukaryotes but virtually lacking among prokaryotes. Concerning the ubiquity of syntrophic microbial communities, it is intriguing why evolution has not lead to more transitions in individuality in the microbial domain. We set out to distinguish syntrophy-specific aspects of major transitions, to investigate why a transition in individuality within a syntrophic pair or community is so rare. We review the field of metabolic communities to identify potential evolutionary trajectories that may lead to a transition. Community properties, like joint metabolic capacity, functional profile, guild composition, assembly and interaction patterns are important concepts that may not only persist stably but according to thought-provoking theories, may provide the heritable information at a higher level of selection. We explore these ideas, relating to concepts of multilevel selection and of informational replication, to assess their relevance in the debate whether microbial communities may inherit community-level information or not.
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Novick A, Doolittle WF. 'Species' without species. STUDIES IN HISTORY AND PHILOSOPHY OF SCIENCE 2021; 87:72-80. [PMID: 34111824 DOI: 10.1016/j.shpsa.2021.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 12/23/2020] [Accepted: 03/18/2021] [Indexed: 06/12/2023]
Abstract
Biological science uses multiple species concepts. Order can be brought to this diversity if we recognize two key features. First, any given species concept is likely to have a patchwork structure, generated by repeated application of the concept to new domains. We illustrate this by showing how two species concepts (biological and ecological) have been modified from their initial eukaryotic applications to apply to prokaryotes. Second, both within and between patches, distinct species concepts may interact and hybridize. We thus defend a semantic picture of the species concept as a collection of interacting patchwork structures. Thus, although not all uses of the term pick out the same kind of unit in nature, the diversity of uses reflects something more than mere polysemy. We suggest that the emphasis on the use of species to pick out natural units is itself problematic, because that is not the term's sole function. In particular, species concepts are used to manage inquiry into processes of speciation, even when these processes do not produce clearly delimited species.
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Affiliation(s)
- Aaron Novick
- Department of Philosophy, University of Washington, Seattle, WA, USA.
| | - W Ford Doolittle
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada
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Brandis G. Reconstructing the Evolutionary History of a Highly Conserved Operon Cluster in Gammaproteobacteria and Bacilli. Genome Biol Evol 2021; 13:6156628. [PMID: 33677562 PMCID: PMC8046335 DOI: 10.1093/gbe/evab041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2021] [Indexed: 12/01/2022] Open
Abstract
The evolution of gene order rearrangements within bacterial chromosomes is a fast process. Closely related species can have almost no conservation in long-range gene order. A prominent exception to this rule is a >40 kb long cluster of five core operons (secE-rpoBC-str-S10-spc-alpha) and three variable adjacent operons (cysS, tufB, and ecf) that together contain 57 genes of the transcriptional and translational machinery. Previous studies have indicated that at least part of this operon cluster might have been present in the last common ancestor of bacteria and archaea. Using 204 whole genome sequences, ∼2 Gy of evolution of the operon cluster were reconstructed back to the last common ancestors of the Gammaproteobacteria and of the Bacilli. A total of 163 independent evolutionary events were identified in which the operon cluster was altered. Further examination showed that the process of disconnecting two operons generally follows the same pattern. Initially, a small number of genes is inserted between the operons breaking the concatenation followed by a second event that fully disconnects the operons. While there is a general trend for loss of gene synteny over time, there are examples of increased alteration rates at specific branch points or within specific bacterial orders. This indicates the recurrence of relaxed selection on the gene order within bacterial chromosomes. The analysis of the alternation events indicates that segmental genome duplications and/or transposon-directed recombination play a crucial role in rearrangements of the operon cluster.
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Affiliation(s)
- Gerrit Brandis
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Sweden
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DeSalle R, Riley M. Should Networks Supplant Tree Building? Microorganisms 2020; 8:E1179. [PMID: 32756444 PMCID: PMC7466111 DOI: 10.3390/microorganisms8081179] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/21/2020] [Accepted: 07/29/2020] [Indexed: 12/15/2022] Open
Abstract
Recent studies suggested that network methods should supplant tree building as the basis of genealogical analysis. This proposition is based upon two arguments. First is the observation that bacterial and archaeal lineages experience processes oppositional to bifurcation and hence the representation of the evolutionary process in a tree like structure is illogical. Second is the argument tree building approaches are circular-you ask for a tree and you get one, which pins a verificationist label on tree building that, if correct, should be the end of phylogenetic analysis as we currently know it. In this review, we examine these questions and suggest that rumors of the death of the bacterial tree of life are exaggerated at best.
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Affiliation(s)
- Rob DeSalle
- Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA;
| | - Margaret Riley
- Department of Biology, University of Massachusetts Amherst, 116 North Pleasant Street, Amherst, MA 01003, USA
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8
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How to Study Classification. Cladistics 2020. [DOI: 10.1017/9781139047678.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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9
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Classification. Cladistics 2020. [DOI: 10.1017/9781139047678.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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10
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Systematics Association Special Volumes. Cladistics 2020. [DOI: 10.1017/9781139047678.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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11
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Relationship Diagrams. Cladistics 2020. [DOI: 10.1017/9781139047678.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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12
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The Separation of Classification and Phylogenetics. Cladistics 2020. [DOI: 10.1017/9781139047678.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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13
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Beyond Classification. Cladistics 2020. [DOI: 10.1017/9781139047678.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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14
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The Interrelationships of Organisms. Cladistics 2020. [DOI: 10.1017/9781139047678.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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15
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How to Study Classification. Cladistics 2020. [DOI: 10.1017/9781139047678.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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16
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Modern Artificial Methods and Raw Data. Cladistics 2020. [DOI: 10.1017/9781139047678.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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17
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Further Myths and More Misunderstandings. Cladistics 2020. [DOI: 10.1017/9781139047678.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Afterword. Cladistics 2020. [DOI: 10.1017/9781139047678.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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19
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Systematics: Exposing Myths. Cladistics 2020. [DOI: 10.1017/9781139047678.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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20
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Essentialism and Typology. Cladistics 2020. [DOI: 10.1017/9781139047678.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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21
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Beyond Classification: How to Study Phylogeny. Cladistics 2020. [DOI: 10.1017/9781139047678.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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22
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How to Study Classification: ‘Total Evidence’ vs. ‘Consensus’, Character Congruence vs. Taxonomic Congruence, Simultaneous Analysis vs. Partitioned Data. Cladistics 2020. [DOI: 10.1017/9781139047678.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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What This Book Is About. Cladistics 2020. [DOI: 10.1017/9781139047678.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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24
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How to Study Classification. Cladistics 2020. [DOI: 10.1017/9781139047678.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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The Cladistic Programme. Cladistics 2020. [DOI: 10.1017/9781139047678.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Index. Cladistics 2020. [DOI: 10.1017/9781139047678.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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27
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Parameters of Classification: Ordo Ab Chao. Cladistics 2020. [DOI: 10.1017/9781139047678.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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28
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Monothetic and Polythetic Taxa. Cladistics 2020. [DOI: 10.1017/9781139047678.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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29
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How to Study Classification: Consensus Techniques and General Classifications. Cladistics 2020. [DOI: 10.1017/9781139047678.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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30
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Non-taxa or the Absence of –Phyly: Paraphyly and Aphyly. Cladistics 2020. [DOI: 10.1017/9781139047678.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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31
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Introduction: Carving Nature at Its Joints, or Why Birds Are Not Dinosaurs and Men Are Not Apes. Cladistics 2020. [DOI: 10.1017/9781139047678.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Preface. Cladistics 2020. [DOI: 10.1017/9781139047678.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Abe T, Akazawa Y, Toyoda A, Niki H, Baba T. Batch-Learning Self-Organizing Map Identifies Horizontal Gene Transfer Candidates and Their Origins in Entire Genomes. Front Microbiol 2020; 11:1486. [PMID: 32719664 PMCID: PMC7350273 DOI: 10.3389/fmicb.2020.01486] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 06/08/2020] [Indexed: 02/05/2023] Open
Abstract
Horizontal gene transfer (HGT) has been widely suggested to play a critical role in the environmental adaptation of microbes; however, the number and origin of the genes in microbial genomes obtained through HGT remain unknown as the frequency of detected HGT events is generally underestimated, particularly in the absence of information on donor sequences. As an alternative to phylogeny-based methods that rely on sequence alignments, we have developed an alignment-free clustering method on the basis of an unsupervised neural network “Batch-Learning Self-Organizing Map (BLSOM)” in which sequence fragments are clustered based solely on oligonucleotide similarity without taxonomical information, to detect HGT candidates and their origin in entire genomes. By mapping the microbial genomic sequences on large-scale BLSOMs constructed with nearly all prokaryotic genomes, HGT candidates can be identified, and their origin assigned comprehensively, even for microbial genomes that exhibit high novelty. By focusing on two types of Alphaproteobacteria, specifically psychrotolerant Sphingomonas strains from an Antarctic lake, we detected HGT candidates using BLSOM and found higher proportions of HGT candidates from organisms belonging to Betaproteobacteria in the genomes of these two Antarctic strains compared with those of continental strains. Further, an origin difference was noted in the HGT candidates found in the two Antarctic strains. Although their origins were highly diversified, gene functions related to the cell wall or membrane biogenesis were shared among the HGT candidates. Moreover, analyses of amino acid frequency suggested that housekeeping genes and some HGT candidates of the Antarctic strains exhibited different characteristics to other continental strains. Lys, Ser, Thr, and Val were the amino acids found to be increased in the Antarctic strains, whereas Ala, Arg, Glu, and Leu were decreased. Our findings strongly suggest a low-temperature adaptation process for microbes that may have arisen convergently as an independent evolutionary strategy in each Antarctic strain. Hence, BLSOM analysis could serve as a powerful tool in not only detecting HGT candidates and their origins in entire genomes, but also in providing novel perspectives into the environmental adaptations of microbes.
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Affiliation(s)
- Takashi Abe
- Department of Information Engineering, Faculty of Engineering, Niigata University, Niigata, Japan
| | - Yu Akazawa
- Department of Information Engineering, Faculty of Engineering, Niigata University, Niigata, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Japan.,Advanced Genomics Center, National Institute of Genetics, Mishima, Japan
| | - Hironori Niki
- Microbial Physiology Laboratory, National Institute of Genetics, Mishima, Japan
| | - Tomoya Baba
- Advanced Genomics Center, National Institute of Genetics, Mishima, Japan.,Joint Support-Center for Data Science Research, Research Organization of Information and Systems, Tokyo, Japan
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34
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Fields C, Levin M. Scale-Free Biology: Integrating Evolutionary and Developmental Thinking. Bioessays 2020; 42:e1900228. [PMID: 32537770 DOI: 10.1002/bies.201900228] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 04/24/2020] [Indexed: 12/16/2022]
Abstract
When the history of life on earth is viewed as a history of cell division, all of life becomes a single cell lineage. The growth and differentiation of this lineage in reciprocal interaction with its environment can be viewed as a developmental process; hence the evolution of life on earth can also be seen as the development of life on earth. Here, in reviewing this field, some potentially fruitful research directions suggested by this change in perspective are highlighted. Variation and selection become, for example, bidirectional information flows between scales, while the notions of "cooperation" and "competition" become scale relative. The language of communication, inference, and information processing becomes more useful than the language of causation to describe the interactions of both homogeneous and heterogeneous living systems at any scale. Emerging scale-free theoretical frameworks such as predictive coding and active inference provide conceptual tools for reconceptualizing biology as the study of a unified, multiscale dynamical system.
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Affiliation(s)
- Chris Fields
- 23 Rue des Lavandieres, 11160 Caunes Minervois, France
| | - Michael Levin
- Allen Discovery Center at Tufts University, Medford, MA, 02155, USA
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35
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Brandis G, Hughes D. The SNAP hypothesis: Chromosomal rearrangements could emerge from positive Selection during Niche Adaptation. PLoS Genet 2020; 16:e1008615. [PMID: 32130223 PMCID: PMC7055797 DOI: 10.1371/journal.pgen.1008615] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 01/17/2020] [Indexed: 12/23/2022] Open
Abstract
The relative linear order of most genes on bacterial chromosomes is not conserved over evolutionary timescales. One explanation is that selection is weak, allowing recombination to randomize gene order by genetic drift. However, most chromosomal rearrangements are deleterious to fitness. In contrast, we propose the hypothesis that rearrangements in gene order are more likely the result of selection during niche adaptation (SNAP). Partial chromosomal duplications occur very frequently by recombination between direct repeat sequences. Duplicated regions may contain tens to hundreds of genes and segregate quickly unless maintained by selection. Bacteria exposed to non-lethal selections (for example, a requirement to grow on a poor nutrient) can adapt by maintaining a duplication that includes a gene that improves relative fitness. Further improvements in fitness result from the loss or inactivation of non-selected genes within each copy of the duplication. When genes that are essential in single copy are lost from different copies of the duplication, segregation is prevented even if the original selection is lifted. Functional gene loss continues until a new genetic equilibrium is reached. The outcome is a rearranged gene order. Mathematical modelling shows that this process of positive selection to adapt to a new niche can rapidly drive rearrangements in gene order to fixation. Signature features (duplication formation and divergence) of the SNAP model were identified in natural isolates from multiple species showing that the initial two steps in the SNAP process can occur with a remarkably high frequency. Further bioinformatic and experimental analyses are required to test if and to which extend the SNAP process acts on bacterial genomes. All life on earth has evolved from a universal common ancestor with a specific order of genes on the chromosome. This order is not maintained in modern species and the standard hypothesis is that changes reflect a lack of strong selection on gene order. Here, we propose an alternative hypothesis, SNAP. The occupation of a novel environment by bacteria is generally a trade-off situation. For example, while the bacteria may not be adapted to grow well under the new conditions, they may benefit by not having to share available resources with other microorganisms. Bacterial populations frequently acquire duplications of chromosomal segments containing genes that can help them adapt to a new environment. Other genes that are also duplicated are not required in two copies so that over time a superfluous copy can be lost. Eventually, the process of duplication and gene loss can lead to the rearrangement of the gene order in the chromosomal segment. The major benefit of this model over the standard hypothesis is that the process is driven by positive selection and can reach fixation rapidly.
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Affiliation(s)
- Gerrit Brandis
- Department of Medical Biochemistry and Microbiology, Biomedical Center, Uppsala University, Uppsala, Sweden
| | - Diarmaid Hughes
- Department of Medical Biochemistry and Microbiology, Biomedical Center, Uppsala University, Uppsala, Sweden
- * E-mail:
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Barnes EM, Carter EL, Lewis JD. Predicting Microbiome Function Across Space Is Confounded by Strain-Level Differences and Functional Redundancy Across Taxa. Front Microbiol 2020; 11:101. [PMID: 32117131 PMCID: PMC7018939 DOI: 10.3389/fmicb.2020.00101] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/17/2020] [Indexed: 12/30/2022] Open
Abstract
Variation in the microbiome among individual organisms may play a critical role in the relative susceptibility of those organisms to infection, disease, and death. However, predicting microbiome function is difficult because of spatial and temporal variation in microbial diversity, and taxonomic diversity is not predictive of microbiome functional diversity. Addressing this issue may be particularly important when addressing pandemic diseases, such as the global amphibian die-off associated with Bd. Some of the most important factors in probiotic development for disease treatment are whether bacteria with desired function can be found on native amphibians in the local environment. To address this issue, we isolated, sequenced, and assayed the cutaneous bacterial communities of Plethodon cinereus along a gradient of land use change. Our results suggest that cutaneous community composition, but not overall diversity, change with changes in land use, but this does not correspond to significant change in Bd-inhibitory function. We found that Bd-inhibition is a functionally redundant trait, but that level of inhibition varies over phylogenetic, spatial, and temporal scales. This research provides further evidence for the importance of continued examination of amphibian microbial communities across environmental gradients, including biotic and abiotic interactions, when considering disease dynamics.
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Affiliation(s)
- Elle M Barnes
- Department of Biological Sciences, Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, United States.,Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
| | - Erin L Carter
- Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
| | - J D Lewis
- Department of Biological Sciences, Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, United States.,Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
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Papale F, Saget J, Bapteste É. Networks Consolidate the Core Concepts of Evolution by Natural Selection. Trends Microbiol 2019; 28:254-265. [PMID: 31866140 DOI: 10.1016/j.tim.2019.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 11/12/2019] [Accepted: 11/18/2019] [Indexed: 02/07/2023]
Abstract
Microbiology has unraveled rich evidence of ongoing reticulate evolutionary processes and complex interactions both within and between cells. These phenomena feature real biological networks, which can logically be analyzed using network-based tools. It is thus not surprising that network sciences, a field independent from evolutionary biology and microbiology, have recently pervasively infused their methods into both fields. Importantly, network tools bring forward observations enhancing the understanding of three core evolutionary concepts: variation, fitness, and heredity. Consequently, our work shows how network sciences can enhance evolutionary theory by explaining the evolution by natural selection of a broad diversity of units of selection, while updating the popular figure of Darwin's tree of life with a comprehensive sketch of the networks of evolution.
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Affiliation(s)
- François Papale
- Departement of Philosophy, University of Montreal, Montréal, QC, H3C 3J7, Canada; Institut de Systématique, Evolution, Biodiversité (ISYEB), Sorbonne Université, CNRS, Museum National d'Histoire Naturelle, EPHE, Université des Antilles, 75005 Paris, France
| | - Jordane Saget
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Sorbonne Université, CNRS, Museum National d'Histoire Naturelle, EPHE, Université des Antilles, 75005 Paris, France
| | - Éric Bapteste
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Sorbonne Université, CNRS, Museum National d'Histoire Naturelle, EPHE, Université des Antilles, 75005 Paris, France.
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Iranzo J, Wolf YI, Koonin EV, Sela I. Gene gain and loss push prokaryotes beyond the homologous recombination barrier and accelerate genome sequence divergence. Nat Commun 2019; 10:5376. [PMID: 31772262 PMCID: PMC6879757 DOI: 10.1038/s41467-019-13429-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 11/07/2019] [Indexed: 02/05/2023] Open
Abstract
Bacterial and archaeal evolution involve extensive gene gain and loss. Thus, phylogenetic trees of prokaryotes can be constructed both by traditional sequence-based methods (gene trees) and by comparison of gene compositions (genome trees). Comparing the branch lengths in gene and genome trees with identical topologies for 34 clusters of closely related bacterial and archaeal genomes, we show here that terminal branches of gene trees are systematically compressed compared to those of genome trees. Thus, sequence evolution is delayed compared to genome evolution by gene gain and loss. The extent of this delay differs widely among bacteria and archaea. Mathematical modeling shows that the divergence delay can result from sequence homogenization by homologous recombination. The model explains how homologous recombination maintains the cohesiveness of the core genome of a species while allowing extensive gene gain and loss within the accessory genome. Once evolving genomes become isolated by barriers impeding homologous recombination, gene and genome evolution processes settle into parallel trajectories, and genomes diverge, resulting in speciation. A significant proportion of the molecular evolution of bacteria and archaea occurs through gene gain and loss. Here Iranzo et al. develop a mathematical model that explains observed differential patterns of sequence evolution vs. gene content evolution as a consequence of homologous recombination.
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Affiliation(s)
- Jaime Iranzo
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA.,Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo-UPM, Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA.
| | - Itamar Sela
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA.
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Affiliation(s)
- Aaron Novick
- Department of Philosophy, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- * E-mail: (AN); (WFD)
| | - W. Ford Doolittle
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- * E-mail: (AN); (WFD)
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40
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Du MZ, Wei W, Qin L, Liu S, Zhang AY, Zhang Y, Zhou H, Guo FB. Co-adaption of tRNA gene copy number and amino acid usage influences translation rates in three life domains. DNA Res 2018; 24:623-633. [PMID: 28992099 PMCID: PMC5726483 DOI: 10.1093/dnares/dsx030] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 06/15/2017] [Indexed: 12/01/2022] Open
Abstract
Although more and more entangled participants of translation process were realized, how they cooperate and co-determine the final translation efficiency still lacks details. Here, we reasoned that the basic translation components, tRNAs and amino acids should be consistent to maximize the efficiency and minimize the cost. We firstly revealed that 310 out of 410 investigated genomes of three domains had significant co-adaptions between the tRNA gene copy numbers and amino acid compositions, indicating that maximum efficiency constitutes ubiquitous selection pressure on protein translation. Furthermore, fast-growing and larger bacteria are found to have significantly better co-adaption and confirmed the effect of this pressure. Within organism, highly expressed proteins and those connected to acute responses have higher co-adaption intensity. Thus, the better co-adaption probably speeds up the growing of cells through accelerating the translation of special proteins. Experimentally, manipulating the tRNA gene copy number to optimize co-adaption between enhanced green fluorescent protein (EGFP) and tRNA gene set of Escherichia coli indeed lifted the translation rate (speed). Finally, as a newly confirmed translation rate regulating mechanism, the co-adaption reflecting translation rate not only deepens our understanding on translation process but also provides an easy and practicable method to improve protein translation rates and productivity.
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Affiliation(s)
| | - Wen Wei
- School of Life Science and Technology
| | - Lei Qin
- School of Life Science and Technology
| | - Shuo Liu
- School of Life Science and Technology
| | - An-Ying Zhang
- School of Life Science and Technology.,Centre for Informational Biology
| | - Yong Zhang
- School of Life Science and Technology.,Centre for Informational Biology
| | - Hong Zhou
- School of Life Science and Technology.,Centre for Informational Biology
| | - Feng-Biao Guo
- School of Life Science and Technology.,Centre for Informational Biology.,Key Laboratory for Neuroinformation of the Ministry of Education, University of Electronic Science and Technology of China, Chengdu, China
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Abstract
The classic Darwinian theory and the Synthetic evolutionary theory and their linear models, while invaluable to study the origins and evolution of species, are not primarily designed to model the evolution of organisations, typically that of ecosystems, nor that of processes. How could evolutionary theory better explain the evolution of biological complexity and diversity? Inclusive network-based analyses of dynamic systems could retrace interactions between (related or unrelated) components. This theoretical shift from a Tree of Life to a Dynamic Interaction Network of Life, which is supported by diverse molecular, cellular, microbiological, organismal, ecological and evolutionary studies, would further unify evolutionary biology.
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Affiliation(s)
- Eric Bapteste
- Sorbonne Universités, UPMC Université Paris 06, Institut de Biologie Paris-Seine (IBPS), F-75005 Paris, France
- CNRS, UMR7138, Institut de Biologie Paris-Seine, F-75005 Paris, France
| | - Philippe Huneman
- Institut d’Histoire et de Philosophie des Sciences et des Techniques (CNRS / Paris I Sorbonne), F-75006 Paris, France
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Braga LPP, Soucy SM, Amgarten DE, da Silva AM, Setubal JC. Bacterial Diversification in the Light of the Interactions with Phages: The Genetic Symbionts and Their Role in Ecological Speciation. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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43
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44
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Fernandez-Lopez R, Redondo S, Garcillan-Barcia MP, de la Cruz F. Towards a taxonomy of conjugative plasmids. Curr Opin Microbiol 2017; 38:106-113. [PMID: 28586714 DOI: 10.1016/j.mib.2017.05.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 05/10/2017] [Accepted: 05/17/2017] [Indexed: 01/14/2023]
Abstract
Conjugative plasmids are the keystone of horizontal gene transfer. Metagenomic research and clinical understanding of plasmid transmission beg for a taxonomical approach to conjugative plasmid classification. Up to now, a meaningful classification was difficult to achieve for lack of appropriate analytical tools. The advent of the genomic era revolutionized the landscape, offering a plethora of plasmid sequences as well as bioinformatic analytical tools. Given the need and the opportunity, in view of the available evidence, a taxonomy of conjugative plasmids is proposed in the hope that it will leverage plasmid studies.
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Affiliation(s)
- Raul Fernandez-Lopez
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria, Santander, Spain
| | - Santiago Redondo
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria, Santander, Spain
| | - M Pilar Garcillan-Barcia
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria, Santander, Spain
| | - Fernando de la Cruz
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria, Santander, Spain.
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Blokesch M. In and out-contribution of natural transformation to the shuffling of large genomic regions. Curr Opin Microbiol 2017; 38:22-29. [PMID: 28458094 DOI: 10.1016/j.mib.2017.04.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 04/01/2017] [Accepted: 04/06/2017] [Indexed: 01/28/2023]
Abstract
Naturally competent bacteria can pull free DNA from their surroundings. This incoming DNA can serve various purposes, ranging from acting as a source of nutrients or DNA stretches for repair to the acquisition of novel genetic information. The latter process defines the natural competence for transformation as a mode of horizontal gene transfer (HGT) and led to its discovery almost a century ago. However, although it is widely accepted that natural competence can contribute to the spread of genetic material among prokaryotes, the question remains whether this mode of HGT can foster the transfer of larger DNA regions or only transfers shorter fragments, given that extracellular DNA is often heavily fragmented. Here, I outline examples of competence-mediated movement of large genomic segments. Moreover, I discuss a recent proposition that transformation is used to cure bacteria of selfish mobile genetic elements. Such a transformation-mediated genome maintenance mechanism could indeed be an important and underappreciated function of natural competence.
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Affiliation(s)
- Melanie Blokesch
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
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46
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Venter SN, Palmer M, Beukes CW, Chan WY, Shin G, van Zyl E, Seale T, Coutinho TA, Steenkamp ET. Practically delineating bacterial species with genealogical concordance. Antonie van Leeuwenhoek 2017; 110:1311-1325. [DOI: 10.1007/s10482-017-0869-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 03/30/2017] [Indexed: 10/19/2022]
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47
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Doolittle WF. Darwinizing Gaia. J Theor Biol 2017; 434:11-19. [PMID: 28237396 DOI: 10.1016/j.jtbi.2017.02.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 02/06/2017] [Accepted: 02/13/2017] [Indexed: 11/26/2022]
Abstract
The Gaia hypothesis of James Lovelock was co-developed with and vigorously promoted by Lynn Margulis, but most mainstream Darwinists scorned and still do not accept the notion. They cannot imagine selection for global stability being realized at the level of the individuals or species that make up the biosphere. Here I suggest that we look at the biogeochemical cycles and other homeostatic processes that might confer stability - rather than the taxa (mostly microbial) that implement them - as the relevant units of selection. By thus focusing our attentions on the "song", not the "singers", a Darwinized Gaia might be developed. Our understanding of evolution by natural selection would however need to be stretched to accommodate differential persistence as well as differential reproduction.
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Affiliation(s)
- W Ford Doolittle
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
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48
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Ellegaard KM, Engel P. Beyond 16S rRNA Community Profiling: Intra-Species Diversity in the Gut Microbiota. Front Microbiol 2016; 7:1475. [PMID: 27708630 PMCID: PMC5030217 DOI: 10.3389/fmicb.2016.01475] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/05/2016] [Indexed: 12/31/2022] Open
Abstract
Interactions with microbes affect many aspects of animal biology, including immune system development, nutrition and health. In vertebrates, the gut microbiota is dominated by a small subset of phyla, but the species composition within these phyla is typically not conserved. Moreover, several recent studies have shown that bacterial species in the gut are composed of a multitude of strains, which frequently co-exist in their host, and may be host-specific. However, since the study of intra-species diversity is challenging, particularly in the setting of complex, host-associated microbial communities, our current understanding of the distribution, evolution and functional relevance of intra-species diversity in the gut is scarce. In order to unravel how genomic diversity translates into phenotypic diversity, community analyses going beyond 16S rRNA profiling, in combination with experimental approaches, are needed. Recently, the honeybee has emerged as a promising model for studying gut bacterial communities, particularly in terms of strain-level diversity. Unlike most other invertebrates, the honeybee gut is colonized by a remarkably consistent and specific core microbiota, which is dominated by only eight bacterial species. As for the vertebrate gut microbiota, these species are composed of highly diverse strains suggesting that similar evolutionary forces shape gut community structures in vertebrates and social insects. In this review, we outline current knowledge on the evolution and functional relevance of strain diversity within the gut microbiota, including recent insights gained from mammals and other animals such as the honeybee. We discuss methodological approaches and propose possible future avenues for studying strain diversity in complex bacterial communities.
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Affiliation(s)
- Kirsten M Ellegaard
- Department of Fundamental Microbiology, University of Lausanne Lausanne, Switzerland
| | - Philipp Engel
- Department of Fundamental Microbiology, University of Lausanne Lausanne, Switzerland
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