1
|
Ślesak I, Ślesak H. From cyanobacteria and cyanophages to chloroplasts: the fate of the genomes of oxyphototrophs and the genes encoding photosystem II proteins. THE NEW PHYTOLOGIST 2024; 242:1055-1067. [PMID: 38439684 DOI: 10.1111/nph.19633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 02/02/2024] [Indexed: 03/06/2024]
Abstract
Chloroplasts are the result of endosymbiosis of cyanobacterial organisms with proto-eukaryotes. The psbA, psbD and psbO genes are present in all oxyphototrophs and encode the D1/D2 proteins of photosystem II (PSII) and PsbO, respectively. PsbO is a peripheral protein that stabilizes the O2-evolving complex in PSII. Of these genes, psbA and psbD remained in the chloroplastic genome, while psbO was transferred to the nucleus. The genomes of selected cyanobacteria, chloroplasts and cyanophages carrying psbA and psbD, respectively, were analysed. The highest density of genes and coding sequences (CDSs) was estimated for the genomes of cyanophages, cyanobacteria and chloroplasts. The synonymous mutation rate (rS) of psbA and psbD in chloroplasts remained almost unchanged and is lower than that of psbO. The results indicate that the decreasing genome size in chloroplasts is more similar to the genome reduction observed in contemporary endosymbiotic organisms than in streamlined genomes of free-living cyanobacteria. The rS of atpA, which encodes the α-subunit of ATP synthase in chloroplasts, suggests that psbA and psbD, and to a lesser extent psbO, are ancient and conservative and arose early in the evolution of oxygenic photosynthesis. The role of cyanophages in the evolution of oxyphototrophs and chloroplastic genomes is discussed.
Collapse
Affiliation(s)
- Ireneusz Ślesak
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239, Kraków, Poland
| | - Halina Ślesak
- Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 3, 30-387, Kraków, Poland
| |
Collapse
|
2
|
Xu Q, Zhang H, Vandenkoornhuyse P, Guo S, Kuzyakov Y, Shen Q, Ling N. Carbon starvation raises capacities in bacterial antibiotic resistance and viral auxiliary carbon metabolism in soils. Proc Natl Acad Sci U S A 2024; 121:e2318160121. [PMID: 38598339 PMCID: PMC11032446 DOI: 10.1073/pnas.2318160121] [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: 10/18/2023] [Accepted: 03/12/2024] [Indexed: 04/12/2024] Open
Abstract
Organic carbon availability in soil is crucial for shaping microbial communities, yet, uncertainties persist concerning microbial adaptations to carbon levels and the ensuing ecological and evolutionary consequences. We investigated organic carbon metabolism, antibiotic resistance, and virus-host interactions in soils subjected to 40 y of chemical and organic fertilization that led to contrasting carbon availability: carbon-poor and carbon-rich soils, respectively. Carbon-poor soils drove the enrichment of putative genes involved in organic matter decomposition and exhibited specialization in utilizing complex organic compounds, reflecting scramble competition. This specialization confers a competitive advantage of microbial communities in carbon-poor soils but reduces their buffering capacity in terms of organic carbon metabolisms, making them more vulnerable to environmental fluctuations. Additionally, in carbon-poor soils, viral auxiliary metabolic genes linked to organic carbon metabolism increased host competitiveness and environmental adaptability through a strategy akin to "piggyback the winner." Furthermore, putative antibiotic resistance genes, particularly in low-abundance drug categories, were enriched in carbon-poor soils as an evolutionary consequence of chemical warfare (i.e., interference competition). This raises concerns about the potential dissemination of antibiotic resistance from conventional agriculture that relies on chemical-only fertilization. Consequently, carbon starvation resulting from long-term chemical-only fertilization increases microbial adaptations to competition, underscoring the importance of implementing sustainable agricultural practices to mitigate the emergence and spread of antimicrobial resistance and to increase soil carbon storage.
Collapse
Affiliation(s)
- Qicheng Xu
- Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing210095, China
- CNRS, UMR 6553 EcoBio, Université de Rennes, Rennes Cedex35042, France
| | - He Zhang
- Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing210095, China
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou730020, China
| | | | - Shiwei Guo
- Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing210095, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen37077, Germany
- Department of Agricultural Soil Science, University of Göttingen, Göttingen37077, Germany
| | - Qirong Shen
- Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing210095, China
| | - Ning Ling
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou730020, China
| |
Collapse
|
3
|
Galtier N. Half a Century of Controversy: The Neutralist/Selectionist Debate in Molecular Evolution. Genome Biol Evol 2024; 16:evae003. [PMID: 38311843 PMCID: PMC10839204 DOI: 10.1093/gbe/evae003] [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] [Accepted: 01/01/2024] [Indexed: 02/06/2024] Open
Abstract
The neutral and nearly neutral theories, introduced more than 50 yr ago, have raised and still raise passionate discussion regarding the forces governing molecular evolution and their relative importance. The debate, initially focused on the amount of within-species polymorphism and constancy of the substitution rate, has spread, matured, and now underlies a wide range of topics and questions. The neutralist/selectionist controversy has structured the field and influences the way molecular evolutionary scientists conceive their research.
Collapse
Affiliation(s)
- Nicolas Galtier
- ISEM, CNRS, IRD, Université de Montpellier, Montpellier, France
| |
Collapse
|
4
|
Takeuchi N, Fullmer MS, Maddock DJ, Poole AM. The Constructive Black Queen hypothesis: new functions can evolve under conditions favouring gene loss. THE ISME JOURNAL 2024; 18:wrae011. [PMID: 38366199 PMCID: PMC10942775 DOI: 10.1093/ismejo/wrae011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 02/18/2024]
Abstract
Duplication is a major route for the emergence of new gene functions. However, the emergence of new gene functions via this route may be reduced in prokaryotes, as redundant genes are often rapidly purged. In lineages with compact, streamlined genomes, it thus appears challenging for novel function to emerge via duplication and divergence. A further pressure contributing to gene loss occurs under Black Queen dynamics, as cheaters that lose the capacity to produce a public good can instead acquire it from neighbouring producers. We propose that Black Queen dynamics can favour the emergence of new function because, under an emerging Black Queen dynamic, there is high gene redundancy spread across a community of interacting cells. Using computational modelling, we demonstrate that new gene functions can emerge under Black Queen dynamics. This result holds even if there is deletion bias due to low duplication rates and selection against redundant gene copies resulting from the high cost associated with carrying a locus. However, when the public good production costs are high, Black Queen dynamics impede the fixation of new functions. Our results expand the mechanisms by which new gene functions can emerge in prokaryotic systems.
Collapse
Affiliation(s)
- Nobuto Takeuchi
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
- Universal Biology Institute, University of Tokyo, Tokyo 113-0033, Japan
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 819-0395, Japan
| | - Matthew S Fullmer
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
| | - Danielle J Maddock
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
| | - Anthony M Poole
- School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
| |
Collapse
|
5
|
Zhang H, Hellweger FL, Luo H. Genome reduction occurred in early Prochlorococcus with an unusually low effective population size. THE ISME JOURNAL 2024; 18:wrad035. [PMID: 38365237 PMCID: PMC10837832 DOI: 10.1093/ismejo/wrad035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/14/2023] [Accepted: 12/20/2023] [Indexed: 02/18/2024]
Abstract
In the oligotrophic sunlit ocean, the most abundant free-living planktonic bacterial lineages evolve convergently through genome reduction. The cyanobacterium Prochlorococcus responsible for 10% global oxygen production is a prominent example. The dominant theory known as "genome streamlining" posits that they have extremely large effective population sizes (Ne) such that selection for metabolic efficiency acts to drive genome reduction. Because genome reduction largely took place anciently, this theory builds on the assumption that their ancestors' Ne was similarly large. Constraining Ne for ancient ancestors is challenging because experimental measurements of extinct organisms are impossible and alternatively reconstructing ancestral Ne with phylogenetic models gives large uncertainties. Here, we develop a new strategy that leverages agent-based modeling to simulate the changes in the genome-wide ratio of radical to conservative nonsynonymous nucleotide substitution rate (dR/dC) in a possible range of Ne in ancestral populations. This proxy shows expected increases with decreases of Ne only when Ne falls to about 10 k - 100 k or lower, magnitudes characteristic of Ne of obligate endosymbiont species where drift drives genome reduction. Our simulations therefore strongly support a scenario where the primary force of Prochlorococcus genome reduction is drift rather than selection.
Collapse
Affiliation(s)
- Hao Zhang
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, 999077, Hong Kong SAR
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518000, China
| | - Ferdi L Hellweger
- Water Quality Engineering, Technical University of Berlin, Berlin, 10623, Germany
| | - Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, 999077, Hong Kong SAR
- Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Shatin, 999077, Hong Kong SAR
| |
Collapse
|
6
|
Wang X, Feng X. Challenges in estimating effective population sizes from metagenome-assembled genomes. Front Microbiol 2024; 14:1331583. [PMID: 38249456 PMCID: PMC10797056 DOI: 10.3389/fmicb.2023.1331583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/15/2023] [Indexed: 01/23/2024] Open
Abstract
Effective population size (Ne) plays a critical role in shaping the relative efficiency between natural selection and genetic drift, thereby serving as a cornerstone for understanding microbial ecological dynamics. Direct Ne estimation relies on neutral genetic diversity within closely related genomes, which is, however, often constrained by the culturing difficulties for the vast majority of prokaryotic lineages. Metagenome-assembled genomes (MAGs) offer a high-throughput alternative for genomic data acquisition, yet their accuracy in Ne estimation has not been fully verified. This study examines the Thermococcus genus, comprising 66 isolated strains and 29 MAGs, to evaluate the reliability of MAGs in Ne estimation. Despite the even distribution across the Thermococcus phylogeny and the comparable internal average nucleotide identity (ANI) between isolate populations and MAG populations, our results reveal consistently lower Ne estimates from MAG populations. This trend of underestimation is also observed in various MAG populations across three other bacterial genera. The underrepresentation of genetic variation in MAGs, including loss of allele frequency data and variable genomic segments, likely contributes to the underestimation of Ne. Our findings underscore the necessity for caution when employing MAGs for evolutionary studies, which often depend on high-quality genome assemblies and nucleotide-level diversity.
Collapse
Affiliation(s)
- Xiaojun Wang
- Shenzhen Research Institute of the Chinese University of Hong Kong, Shenzhen, China
| | - Xiaoyuan Feng
- Shenzhen Research Institute of the Chinese University of Hong Kong, Shenzhen, China
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| |
Collapse
|
7
|
Kjellin J, Lee D, Steinsland H, Dwane R, Barth Vedoy O, Hanevik K, Koskiniemi S. Colicins and T6SS-based competition systems enhance enterotoxigenic E. coli (ETEC) competitiveness. Gut Microbes 2024; 16:2295891. [PMID: 38149626 PMCID: PMC10761095 DOI: 10.1080/19490976.2023.2295891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 12/13/2023] [Indexed: 12/28/2023] Open
Abstract
Diarrheal diseases are still a significant problem for humankind, causing approximately half a million deaths annually. To cause diarrhea, enteric bacterial pathogens must first colonize the gut, which is a niche occupied by the normal bacterial microbiota. Therefore, the ability of pathogenic bacteria to inhibit the growth of other bacteria can facilitate the colonization process. Although enterotoxigenic Escherichia coli (ETEC) is one of the major causative agents of diarrheal diseases, little is known about the competition systems found in and used by ETEC and how they contribute to the ability of ETEC to colonize a host. Here, we collected a set of 94 fully assembled ETEC genomes by performing whole-genome sequencing and mining the NCBI RefSeq database. Using this set, we performed a comprehensive search for delivered bacterial toxins and investigated how these toxins contribute to ETEC competitiveness in vitro. We found that type VI secretion systems (T6SS) were widespread among ETEC (n = 47). In addition, several closely related ETEC strains were found to encode Colicin Ia and T6SS (n = 8). These toxins provide ETEC competitive advantages during in vitro competition against other E. coli, suggesting that the role of T6SS as well as colicins in ETEC biology has until now been underappreciated.
Collapse
Affiliation(s)
- Jonas Kjellin
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Danna Lee
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Hans Steinsland
- CISMAC, Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Rachel Dwane
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Oda Barth Vedoy
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Kurt Hanevik
- Department of Clinical Science, University of Bergen, Bergen, Norway
- National centre for Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Sanna Koskiniemi
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| |
Collapse
|
8
|
Zimmerman S, Tierney BT, Patel CJ, Kostic AD. Quantifying Shared and Unique Gene Content across 17 Microbial Ecosystems. mSystems 2023; 8:e0011823. [PMID: 37022232 PMCID: PMC10134805 DOI: 10.1128/msystems.00118-23] [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: 02/08/2023] [Accepted: 02/27/2023] [Indexed: 04/07/2023] Open
Abstract
Measuring microbial diversity is traditionally based on microbe taxonomy. Here, in contrast, we aimed to quantify heterogeneity in microbial gene content across 14,183 metagenomic samples spanning 17 ecologies, including 6 human associated, 7 nonhuman host associated, and 4 in other nonhuman host environments. In total, we identified 117,629,181 nonredundant genes. The vast majority of genes (66%) occurred in only one sample (i.e., "singletons"). In contrast, we found 1,864 sequences present in every metagenome, but not necessarily every bacterial genome. Additionally, we report data sets of other ecology-associated genes (e.g., abundant in only gut ecosystems) and simultaneously demonstrated that prior microbiome gene catalogs are both incomplete and inaccurately cluster microbial genetic life (e.g., at gene sequence identities that are too restrictive). We provide our results and the sets of environmentally differentiating genes described above at http://www.microbial-genes.bio. IMPORTANCE The amount of shared genetic elements has not been quantified between the human microbiome and other host- and non-host-associated microbiomes. Here, we made a gene catalog of 17 different microbial ecosystems and compared them. We show that most species shared between environment and human gut microbiomes are pathogens and that prior gene catalogs described as "nearly complete" are far from it. Additionally, over two-thirds of all genes only appear in a single sample, and only 1,864 genes (0.001%) are found in all types of metagenomes. These results highlight the large diversity between metagenomes and reveal a new, rare class of genes, those found in every type of metagenome, but not every microbial genome.
Collapse
Affiliation(s)
- Samuel Zimmerman
- Section on Pathophysiology and Molecular Pharmacology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Braden T. Tierney
- Section on Pathophysiology and Molecular Pharmacology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Department of Biomedical Informatics, Harvard Medical School, Boston, Massachusetts, USA
| | - Chirag J. Patel
- Department of Biomedical Informatics, Harvard Medical School, Boston, Massachusetts, USA
| | - Aleksandar D. Kostic
- Section on Pathophysiology and Molecular Pharmacology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
9
|
Rodríguez-Gijón A, Buck M, Andersson AF, Izabel-Shen D, Nascimento FJA, Garcia SL. Linking prokaryotic genome size variation to metabolic potential and environment. ISME COMMUNICATIONS 2023; 3:25. [PMID: 36973336 PMCID: PMC10042847 DOI: 10.1038/s43705-023-00231-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/02/2023] [Accepted: 03/14/2023] [Indexed: 03/29/2023]
Abstract
While theories and models have appeared to explain genome size as a result of evolutionary processes, little work has shown that genome sizes carry ecological signatures. Our work delves into the ecological implications of microbial genome size variation in benthic and pelagic habitats across environmental gradients of the brackish Baltic Sea. While depth is significantly associated with genome size in benthic and pelagic brackish metagenomes, salinity is only correlated to genome size in benthic metagenomes. Overall, we confirm that prokaryotic genome sizes in Baltic sediments (3.47 Mbp) are significantly bigger than in the water column (2.96 Mbp). While benthic genomes have a higher number of functions than pelagic genomes, the smallest genomes coded for a higher number of module steps per Mbp for most of the functions irrespective of their environment. Some examples of this functions are amino acid metabolism and central carbohydrate metabolism. However, we observed that nitrogen metabolism was almost absent in pelagic genomes and was mostly present in benthic genomes. Finally, we also show that Bacteria inhabiting Baltic sediments and water column not only differ in taxonomy, but also in their metabolic potential, such as the Wood-Ljungdahl pathway or the presence of different hydrogenases. Our work shows how microbial genome size is linked to abiotic factors in the environment, metabolic potential and taxonomic identity of Bacteria and Archaea within aquatic ecosystems.
Collapse
Affiliation(s)
- Alejandro Rodríguez-Gijón
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, 106 91, Sweden.
- Science for Life Laboratory, Stockholm, Sweden.
| | - Moritz Buck
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anders F Andersson
- Science for Life Laboratory, Stockholm, Sweden
- Department of Gene Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Dandan Izabel-Shen
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, 106 91, Sweden
| | - Francisco J A Nascimento
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, 106 91, Sweden
- Baltic Sea Centre, Stockholm University, Stockholm, Sweden
| | - Sarahi L Garcia
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, 106 91, Sweden.
- Science for Life Laboratory, Stockholm, Sweden.
| |
Collapse
|
10
|
Ngugi DK, Acinas SG, Sánchez P, Gasol JM, Agusti S, Karl DM, Duarte CM. Abiotic selection of microbial genome size in the global ocean. Nat Commun 2023; 14:1384. [PMID: 36914646 PMCID: PMC10011403 DOI: 10.1038/s41467-023-36988-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 02/27/2023] [Indexed: 03/14/2023] Open
Abstract
Strong purifying selection is considered a major evolutionary force behind small microbial genomes in the resource-poor photic ocean. However, very little is currently known about how the size of prokaryotic genomes evolves in the global ocean and whether patterns reflect shifts in resource availability in the epipelagic and relatively stable deep-sea environmental conditions. Using 364 marine microbial metagenomes, we investigate how the average genome size of uncultured planktonic prokaryotes varies across the tropical and polar oceans to the hadal realm. We find that genome size is highest in the perennially cold polar ocean, reflecting elongation of coding genes and gene dosage effects due to duplications in the interior ocean microbiome. Moreover, the rate of change in genome size due to temperature is 16-fold higher than with depth up to 200 m. Our results demonstrate how environmental factors can influence marine microbial genome size selection and ecological strategies of the microbiome.
Collapse
Affiliation(s)
- David K Ngugi
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.
| | - Silvia G Acinas
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Pablo Sánchez
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Josep M Gasol
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Susana Agusti
- King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal, Saudi Arabia
| | - David M Karl
- Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaií at Mãnoa, Honolulu, USA
| | - Carlos M Duarte
- King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal, Saudi Arabia
| |
Collapse
|
11
|
Mohamed F, Ruiz Rodriguez LG, Zorzoli A, Dorfmueller HC, Raya RR, Mozzi F. Genomic diversity in Fructobacillus spp. isolated from fructose-rich niches. PLoS One 2023; 18:e0281839. [PMID: 36795789 PMCID: PMC9934391 DOI: 10.1371/journal.pone.0281839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/31/2023] [Indexed: 02/17/2023] Open
Abstract
The Fructobacillus genus is a group of obligately fructophilic lactic acid bacteria (FLAB) that requires the use of fructose or another electron acceptor for their growth. In this work, we performed a comparative genomic analysis within the genus Fructobacillus by using 24 available genomes to evaluate genomic and metabolic differences among these organisms. In the genome of these strains, which varies between 1.15- and 1.75-Mbp, nineteen intact prophage regions, and seven complete CRISPR-Cas type II systems were found. Phylogenetic analyses located the studied genomes in two different clades. A pangenome analysis and a functional classification of their genes revealed that genomes of the first clade presented fewer genes involved in the synthesis of amino acids and other nitrogen compounds. Moreover, the presence of genes strictly related to the use of fructose and electron acceptors was variable within the genus, although these variations were not always related to the phylogeny.
Collapse
Affiliation(s)
- Florencia Mohamed
- Centro de Referencia para Lactobacilos (CERELA)-CONICET, San Miguel de Tucumán, Tucumán, Argentina
| | | | - Azul Zorzoli
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Helge C. Dorfmueller
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Raúl R. Raya
- Centro de Referencia para Lactobacilos (CERELA)-CONICET, San Miguel de Tucumán, Tucumán, Argentina
| | - Fernanda Mozzi
- Centro de Referencia para Lactobacilos (CERELA)-CONICET, San Miguel de Tucumán, Tucumán, Argentina
| |
Collapse
|
12
|
Howden BP, Giulieri SG, Wong Fok Lung T, Baines SL, Sharkey LK, Lee JYH, Hachani A, Monk IR, Stinear TP. Staphylococcus aureus host interactions and adaptation. Nat Rev Microbiol 2023; 21:380-395. [PMID: 36707725 PMCID: PMC9882747 DOI: 10.1038/s41579-023-00852-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 96.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2023] [Indexed: 01/28/2023]
Abstract
Invasive Staphylococcus aureus infections are common, causing high mortality, compounded by the propensity of the bacterium to develop drug resistance. S. aureus is an excellent case study of the potential for a bacterium to be commensal, colonizing, latent or disease-causing; these states defined by the interplay between S. aureus and host. This interplay is multidimensional and evolving, exemplified by the spread of S. aureus between humans and other animal reservoirs and the lack of success in vaccine development. In this Review, we examine recent advances in understanding the S. aureus-host interactions that lead to infections. We revisit the primary role of neutrophils in controlling infection, summarizing the discovery of new immune evasion molecules and the discovery of new functions ascribed to well-known virulence factors. We explore the intriguing intersection of bacterial and host metabolism, where crosstalk in both directions can influence immune responses and infection outcomes. This Review also assesses the surprising genomic plasticity of S. aureus, its dualism as a multi-mammalian species commensal and opportunistic pathogen and our developing understanding of the roles of other bacteria in shaping S. aureus colonization.
Collapse
Affiliation(s)
- Benjamin P. Howden
- grid.1008.90000 0001 2179 088XCentre for Pathogen Genomics, The University of Melbourne, Melbourne, Victoria Australia ,grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.410678.c0000 0000 9374 3516Department of Infectious Diseases, Austin Health, Heidelberg, Victoria Australia ,grid.416153.40000 0004 0624 1200Microbiology Department, Royal Melbourne Hospital, Melbourne, Victoria Australia
| | - Stefano G. Giulieri
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.416153.40000 0004 0624 1200Victorian Infectious Diseases Service, Royal Melbourne Hospital, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Tania Wong Fok Lung
- grid.21729.3f0000000419368729Department of Paediatrics, Columbia University, New York, NY USA
| | - Sarah L. Baines
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Liam K. Sharkey
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Jean Y. H. Lee
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.419789.a0000 0000 9295 3933Department of Infectious Diseases, Monash Health, Clayton, Victoria Australia
| | - Abderrahman Hachani
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Ian R. Monk
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Timothy P. Stinear
- grid.1008.90000 0001 2179 088XCentre for Pathogen Genomics, The University of Melbourne, Melbourne, Victoria Australia ,grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| |
Collapse
|
13
|
McLaughlin RW. Robinsoniella peoriensis: an emerging pathogen with few virulence factors. INTERNATIONAL MICROBIOLOGY : THE OFFICIAL JOURNAL OF THE SPANISH SOCIETY FOR MICROBIOLOGY 2023; 26:135-142. [PMID: 36219351 DOI: 10.1007/s10123-022-00281-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/28/2022] [Accepted: 10/04/2022] [Indexed: 01/06/2023]
Abstract
Robinsoniella peoriensis is a Gram-positive bacterium which is anaerobic, spore-forming, and non-motile. It was initially isolated and characterized from feces and swine manure. Strains of this species have since been identified from different mammalian and non-mammalian gastrointestinal tracts. Strains have also been isolated from a variety of human infections, such as bacteremia, bone infections, and skin structures. R. peoriensis has recently been reported as causative for pyometra, which could result in death in the absence of sufficient antimicrobial treatment. However, to the author's knowledge, there has not been a single virulence factor identified. A major challenge of modern medicine is the failure of conventional procedures to characterize the capability of an emerging pathogen to cause disease. The goal of this study is to initially characterize the pathogenicity of this bacterium using a pathogenomics approach.
Collapse
|
14
|
Anderson BD, Bisanz JE. Challenges and opportunities of strain diversity in gut microbiome research. Front Microbiol 2023; 14:1117122. [PMID: 36876113 PMCID: PMC9981649 DOI: 10.3389/fmicb.2023.1117122] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/24/2023] [Indexed: 02/19/2023] Open
Abstract
Just because two things are related does not mean they are the same. In analyzing microbiome data, we are often limited to species-level analyses, and even with the ability to resolve strains, we lack comprehensive databases and understanding of the importance of strain-level variation outside of a limited number of model organisms. The bacterial genome is highly plastic with gene gain and loss occurring at rates comparable or higher than de novo mutations. As such, the conserved portion of the genome is often a fraction of the pangenome which gives rise to significant phenotypic variation, particularly in traits which are important in host microbe interactions. In this review, we discuss the mechanisms that give rise to strain variation and methods that can be used to study it. We identify that while strain diversity can act as a major barrier in interpreting and generalizing microbiome data, it can also be a powerful tool for mechanistic research. We then highlight recent examples demonstrating the importance of strain variation in colonization, virulence, and xenobiotic metabolism. Moving past taxonomy and the species concept will be crucial for future mechanistic research to understand microbiome structure and function.
Collapse
Affiliation(s)
- Benjamin D Anderson
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, United States
| | - Jordan E Bisanz
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, United States.,The Penn State Microbiome Center, Huck Institutes of the Life Sciences, University Park, PA, United States
| |
Collapse
|
15
|
Matsui Y, Nagai M, Ying BW. Growth rate-associated transcriptome reorganization in response to genomic, environmental, and evolutionary interruptions. Front Microbiol 2023; 14:1145673. [PMID: 37032868 PMCID: PMC10073601 DOI: 10.3389/fmicb.2023.1145673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/02/2023] [Indexed: 04/11/2023] Open
Abstract
The genomic, environmental, and evolutionary interruptions caused the changes in bacterial growth, which were stringently associated with changes in gene expression. The growth and gene expression changes remained unclear in response to these interruptions that occurred combinative. As a pilot study, whether and how bacterial growth was affected by the individual and dual interruptions of genome reduction, environmental stress, and adaptive evolution were investigated. Growth assay showed that the presence of the environmental stressors, i.e., threonine and chloramphenicol, significantly decreased the growth rate of the wild-type Escherichia coli, whereas not that of the reduced genome. It indicated a canceling effect in bacterial growth due to the dual interruption of the genomic and environmental changes. Experimental evolution of the reduced genome released the canceling effect by improving growth fitness. Intriguingly, the transcriptome architecture maintained a homeostatic chromosomal periodicity regardless of the genomic, environmental, and evolutionary interruptions. Negative epistasis in transcriptome reorganization was commonly observed in response to the dual interruptions, which might contribute to the canceling effect. It was supported by the changes in the numbers of differentially expressed genes (DEGs) and the enriched regulons and functions. Gene network analysis newly constructed 11 gene modules, one out of which was correlated to the growth rate. Enrichment of DEGs in these modules successfully categorized them into three types, i.e., conserved, responsive, and epistatic. Taken together, homeostasis in transcriptome architecture was essential to being alive, and it might be attributed to the negative epistasis in transcriptome reorganization and the functional differentiation in gene modules. The present study directly connected bacterial growth fitness with transcriptome reorganization and provided a global view of how microorganisms responded to genomic, environmental, and evolutionary interruptions for survival from wild nature.
Collapse
|
16
|
Pincheira‐Donoso D, Harvey LP, Johnson JV, Hudson D, Finn C, Goodyear LEB, Guirguis J, Hyland EM, Hodgson DJ. Genome size does not influence extinction risk in the world's amphibians. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | - Lilly P. Harvey
- School of Science and Technology Nottingham Trent University Nottingham UK
| | - Jack V. Johnson
- School of Biological Sciences Queen's University Belfast Belfast UK
| | - Dave Hudson
- Centre for Ecology and Conservation, College of Life and Environmental Sciences University of Exeter Penryn UK
| | - Catherine Finn
- School of Biological Sciences Queen's University Belfast Belfast UK
| | | | - Jacinta Guirguis
- School of Biological Sciences Queen's University Belfast Belfast UK
| | - Edel M. Hyland
- School of Biological Sciences Queen's University Belfast Belfast UK
| | - Dave J. Hodgson
- Centre for Ecology and Conservation, College of Life and Environmental Sciences University of Exeter Penryn UK
| |
Collapse
|
17
|
France MT, Brown SE, Rompalo AM, Brotman RM, Ravel J. Identification of shared bacterial strains in the vaginal microbiota of related and unrelated reproductive-age mothers and daughters using genome-resolved metagenomics. PLoS One 2022; 17:e0275908. [PMID: 36288274 PMCID: PMC9604009 DOI: 10.1371/journal.pone.0275908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/26/2022] [Indexed: 11/29/2022] Open
Abstract
It has been suggested that the human microbiome might be vertically transmitted from mother to offspring and that early colonizers may play a critical role in development of the immune system. Studies have shown limited support for the vertical transmission of the intestinal microbiota but the derivation of the vaginal microbiota remains largely unknown. Although the vaginal microbiota of children and reproductive age women differ in composition, the vaginal microbiota could be vertically transmitted. To determine whether there was any support for this hypothesis, we examined the vaginal microbiota of daughter-mother pairs from the Baltimore metropolitan area (ages 14-27, 32-51; n = 39). We assessed whether the daughter's microbiota was similar in composition to their mother's using metataxonomics. Permutation tests revealed that while some pairs did have similar vaginal microbiota, the degree of similarity did not exceed that expected by chance. Genome-resolved metagenomics was used to identify shared bacterial strains in a subset of the families (n = 22). We found a small number of bacterial strains that were shared between mother-daughter pairs but identified more shared strains between individuals from different families, indicating that vaginal bacteria may display biogeographic patterns. Earlier-in-life studies are needed to demonstrate vertical transmission of the vaginal microbiota.
Collapse
Affiliation(s)
- Michael T. France
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Sarah E. Brown
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Anne M. Rompalo
- Division of Infectious Diseases, John Hopkins School of Medicine, Baltimore, Maryland, United States of America
| | - Rebecca M. Brotman
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Jacques Ravel
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| |
Collapse
|
18
|
Giulieri SG, Guérillot R, Duchene S, Hachani A, Daniel D, Seemann T, Davis JS, Tong SYC, Young BC, Wilson DJ, Stinear TP, Howden BP. Niche-specific genome degradation and convergent evolution shaping Staphylococcus aureus adaptation during severe infections. eLife 2022; 11:77195. [PMID: 35699423 PMCID: PMC9270034 DOI: 10.7554/elife.77195] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/08/2022] [Indexed: 11/13/2022] Open
Abstract
During severe infections, Staphylococcus aureus moves from its colonising sites to blood and tissues and is exposed to new selective pressures, thus, potentially driving adaptive evolution. Previous studies have shown the key role of the agr locus in S. aureus pathoadaptation; however, a more comprehensive characterisation of genetic signatures of bacterial adaptation may enable prediction of clinical outcomes and reveal new targets for treatment and prevention of these infections. Here, we measured adaptation using within-host evolution analysis of 2590 S. aureus genomes from 396 independent episodes of infection. By capturing a comprehensive repertoire of single nucleotide and structural genome variations, we found evidence of a distinctive evolutionary pattern within the infecting populations compared to colonising bacteria. These invasive strains had up to 20-fold enrichments for genome degradation signatures and displayed significantly convergent mutations in a distinctive set of genes, linked to antibiotic response and pathogenesis. In addition to agr-mediated adaptation, we identified non-canonical, genome-wide significant loci including sucA-sucB and stp1. The prevalence of adaptive changes increased with infection extent, emphasising the clinical significance of these signatures. These findings provide a high-resolution picture of the molecular changes when S. aureus transitions from colonisation to severe infection and may inform correlation of infection outcomes with adaptation signatures. The bacterium Staphylococcus aureus lives harmlessly on our skin and noses. However, occasionally, it gets into our blood and internal organs, such as our bones and joints, where it causes severe, long-lasting infections that are difficult to treat. Over time, S. aureus acquire characteristics that help them to adapt to different locations, such as transitioning from the nose to the blood, and avoid being killed by antibiotics. Previous studies have identified changes, or ‘mutations’, in genes that are likely to play an important role in this evolutionary process. One of these genes, called accessory gene regulator (or agr for short), has been shown to control the mechanisms S. aureus use to infect cells and disseminate in the body. However, it is unclear if there are changes in other genes that also help S. aureus adapt to life inside the human body. To help resolve this mystery, Giulieri et al. collected 2,500 samples of S. aureus from almost 400 people. This included bacteria harmlessly living on the skin or in the nose, as well as strains that caused an infection. Gene sequencing revealed a small number of genes, referred to as ‘adaptive genes’, that often acquire mutations during infection. Of these, agr was the most commonly altered. However, mutations in less well-known genes were also identified: some of these genes are related to resistance to antibiotics, while others are involved in chemical processes that help the bacteria to process nutrients. Most mutations were caused by random errors being introduced in to the bacteria’s genetic code which stopped genes from working. However, in some cases, genes were turned off by small fragments of DNA moving around and inserting themselves into different parts of the genome. This study highlights a group of genes that help S. aureus to thrive inside the body and cause severe and prolonged infections. If these results can be confirmed, it may help to guide which antibiotics are used to treat different infections. Furthermore, understanding which genes are important for infection could lead to new strategies for eliminating this dangerous bacterium.
Collapse
Affiliation(s)
- Stefano G Giulieri
- Department of Microbiology and Immunology, University of Melbourne, Parkville, Australia
| | - Romain Guérillot
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Sebastian Duchene
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Diane Daniel
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Torsten Seemann
- Microbiological Diagnostic Unit, University of Melbourne, Melbourne, Australia
| | - Joshua S Davis
- Department of Infectious Diseases, John Hunter Hospital, Newcastle, Australia
| | - Steven Y C Tong
- Victorian Infectious Diseases Service, University of Melbourne, Melbourne, Australia
| | | | | | - Timothy P Stinear
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Benjamin P Howden
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| |
Collapse
|
19
|
Sakai A, Deich CR, Nelissen FHT, Jonker AJ, Bittencourt DMDC, Kempes CP, Wise KS, Heus HA, Huck WTS, Adamala KP, Glass JI. Traditional Protocols and Optimization Methods Lead to Absent Expression in a Mycoplasma Cell-Free Gene Expression Platform. Synth Biol (Oxf) 2022; 7:ysac008. [PMID: 35774105 PMCID: PMC9239315 DOI: 10.1093/synbio/ysac008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 04/11/2022] [Accepted: 05/20/2022] [Indexed: 11/23/2022] Open
Abstract
Cell-free expression (CFE) systems are one of the main platforms for building synthetic cells. A major drawback is the orthogonality of cell-free systems across species. To generate a CFE system compatible with recently established minimal cell constructs, we attempted to optimize a Mycoplasma bacterium-based CFE system using lysates of the genome-minimized cell JCVI-syn3A (Syn3A) and its close phylogenetic relative Mycoplasma capricolum (Mcap). To produce mycoplasma-derived crude lysates, we systematically tested methods commonly used for bacteria, based on the S30 protocol of Escherichia coli. Unexpectedly, after numerous attempts to optimize lysate production methods or composition of feeding buffer, none of the Mcap or Syn3A lysates supported cell-free gene expression. Only modest levels of in vitro transcription of RNA aptamers were observed. While our experimental systems were intended to perform transcription and translation, our assays focused on RNA. Further investigations identified persistently high ribonuclease (RNase) activity in all lysates, despite removal of recognizable nucleases from the respective genomes and attempts to inhibit nuclease activities in assorted CFE preparations. An alternative method using digitonin to permeabilize the mycoplasma cell membrane produced a lysate with diminished RNase activity yet still was unable to support cell-free gene expression. We found that intact mycoplasma cells poisoned E. coli cell-free extracts by degrading ribosomal RNAs, indicating that the mycoplasma cells, even the minimal cell, have a surface-associated RNase activity. However, it is not clear which gene encodes the RNase. This work summarizes attempts to produce mycoplasma-based CFE and serves as a cautionary tale for researchers entering this field.
Graphical Abstract
Collapse
Affiliation(s)
- Andrei Sakai
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Christopher R Deich
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 Washington Avenue SE, Minneapolis, MN 55455, USA
| | - Frank H T Nelissen
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Aafke J Jonker
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Daniela M de C Bittencourt
- The J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037, USA
- Embrapa Genetic Resources and Biotechnology/National Institute of Science and Technology - Synthetic Biology, Parque Estação Biológica, PqEB, Av. W5 Norte (final), Brasília, DF, 70770-917, Brazil, Norte (final), Brasília, DF, 70770-917, Brazil
| | | | - Kim S Wise
- The J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037, USA
| | - Hans A Heus
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Wilhelm T S Huck
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
| | - Katarzyna P Adamala
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 Washington Avenue SE, Minneapolis, MN 55455, USA
| | - John I Glass
- The J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037, USA
| |
Collapse
|
20
|
Martinez-Gutierrez CA, Aylward FO. Genome size distributions in bacteria and archaea are strongly linked to evolutionary history at broad phylogenetic scales. PLoS Genet 2022; 18:e1010220. [PMID: 35605022 PMCID: PMC9166353 DOI: 10.1371/journal.pgen.1010220] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 06/03/2022] [Accepted: 04/26/2022] [Indexed: 12/30/2022] Open
Abstract
The evolutionary forces that determine genome size in bacteria and archaea have been the subject of intense debate over the last few decades. Although the preferential loss of genes observed in prokaryotes is explained through the deletional bias, factors promoting and preventing the fixation of such gene losses often remain unclear. Importantly, statistical analyses on this topic typically do not consider the potential bias introduced by the shared ancestry of many lineages, which is critical when using species as data points because of the potential dependence on residuals. In this study, we investigated the genome size distributions across a broad diversity of bacteria and archaea to evaluate if this trait is phylogenetically conserved at broad phylogenetic scales. After model fit, Pagel’s lambda indicated a strong phylogenetic signal in genome size data, suggesting that the diversification of this trait is influenced by shared evolutionary histories. We used a phylogenetic generalized least-squares analysis (PGLS) to test whether phylogeny influences the predictability of genome size from dN/dS ratios and 16S copy number, two variables that have been previously linked to genome size. These results confirm that failure to account for evolutionary history can lead to biased interpretations of genome size predictors. Overall, our results indicate that although bacteria and archaea can rapidly gain and lose genetic material through gene transfers and deletions, respectively, phylogenetic signal for genome size distributions can still be recovered at broad phylogenetic scales that should be taken into account when inferring the drivers of genome size evolution. The evolutionary forces driving genome size in bacteria and archaea have been subject to debate during the last decades. Typically, independent comparative analyses have suggested that unique variables, such as the strength of selection, environmental complexity, and mutation rate, are the main drivers of this trait, without considering for potential biases derived from shared ancestry. Here, we applied a phylogeny-based statistical approach to assess how tightly genome size in bacteria and archaea is linked to evolutionary history. Moreover, we also evaluated the predictability of genome size from the strength of purifying selection and ecological strategy on a broad diversity of bacteria and archaea genomes under a phylogenetic comparative framework. Our approach indicates that despite the ability of bacteria and archaea to rapidly exchange genes, a strong phylogenetic signal to genome size distributions can be recovered at broad phylogenetic scales.
Collapse
Affiliation(s)
| | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, Virginia, United States of America
| |
Collapse
|
21
|
Grébert T, Garczarek L, Daubin V, Humily F, Marie D, Ratin M, Devailly A, Farrant GK, Mary I, Mella-Flores D, Tanguy G, Labadie K, Wincker P, Kehoe DM, Partensky F. Diversity and evolution of pigment types in marine Synechococcus cyanobacteria. Genome Biol Evol 2022; 14:6547267. [PMID: 35276007 PMCID: PMC8995045 DOI: 10.1093/gbe/evac035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 11/14/2022] Open
Abstract
Synechococcus cyanobacteria are ubiquitous and abundant in the marine environment and contribute to an estimated 16% of the ocean net primary productivity. Their light-harvesting complexes, called phycobilisomes (PBS), are composed of a conserved allophycocyanin core, from which radiates six to eight rods with variable phycobiliprotein and chromophore content. This variability allows Synechococcus cells to optimally exploit the wide variety of spectral niches existing in marine ecosystems. Seven distinct pigment types or subtypes have been identified so far in this taxon based on the phycobiliprotein composition and/or the proportion of the different chromophores in PBS rods. Most genes involved in their biosynthesis and regulation are located in a dedicated genomic region called the PBS rod region. Here, we examine the variability of gene content and organization of this genomic region in a large set of sequenced isolates and natural populations of Synechococcus representative of all known pigment types. All regions start with a tRNA-PheGAA and some possess mobile elements for DNA integration and site-specific recombination, suggesting that their genomic variability relies in part on a “tycheposon”-like mechanism. Comparison of the phylogenies obtained for PBS and core genes revealed that the evolutionary history of PBS rod genes differs from the core genome and is characterized by the co-existence of different alleles and frequent allelic exchange. We propose a scenario for the evolution of the different pigment types and highlight the importance of incomplete lineage sorting in maintaining a wide diversity of pigment types in different Synechococcus lineages despite multiple speciation events.
Collapse
Affiliation(s)
- Théophile Grébert
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Laurence Garczarek
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Vincent Daubin
- Université Lyon 1, UMR 5558 Biometry and Evolutionary Biology, 69622 Villeurbanne, France
| | - Florian Humily
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Dominique Marie
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Morgane Ratin
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Alban Devailly
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Gregory K Farrant
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Isabelle Mary
- Université Clermont Auvergne, CNRS, Laboratoire Microorganismes: Génome et Environnement, 63000 Clermont-Ferrand, France
| | - Daniella Mella-Flores
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| | - Gwenn Tanguy
- Centre National de la Recherche Scientifique, FR 2424, Station Biologique, 29680 Roscoff, France
| | - Karine Labadie
- Genoscope, Institut de biologie François-Jacob, Commissariat à l'Énergie Atomique (CEA), Université Paris-Saclay, Evry, France
| | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut de biologie François Jacob, CEA, CNRS, Université d'Evry, Université Paris-Saclay, Evry, France
| | - David M Kehoe
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Frédéric Partensky
- Sorbonne Université, Centre National de la Recherche Scientifique, UMR 7144 Adaptation and Diversity in the Marine Environment, Station Biologique, 29680 Roscoff, France
| |
Collapse
|
22
|
Kurokawa M, Nishimura I, Ying BW. Experimental Evolution Expands the Breadth of Adaptation to an Environmental Gradient Correlated With Genome Reduction. Front Microbiol 2022; 13:826894. [PMID: 35154062 PMCID: PMC8826082 DOI: 10.3389/fmicb.2022.826894] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/06/2022] [Indexed: 11/28/2022] Open
Abstract
Whether and how adaptive evolution adjusts the breadth of adaptation in coordination with the genome are essential issues for connecting evolution with ecology. To address these questions, experimental evolution in five Escherichia coli strains carrying either the wild-type genome or a reduced genome was performed in a defined minimal medium (C0). The ancestral and evolved populations were subsequently subjected to fitness and chemical niche analyses across an environmental gradient with 29 combinations of eight chemical components of the minimal medium. The results showed that adaptation was achieved not only specific to the evolutionary condition (C0), but also generally, to the environmental gradient; that is, the breadth of adaptation to the eight chemical niches was expanded. The magnitudes of the adaptive improvement and the breadth increase were both correlated with genome reduction and were highly significant in two out of eight niches (i.e., glucose and sulfate). The direct adaptation-induced correlated adaptation to the environmental gradient was determined by only a few genome mutations. An additive increase in fitness associated with the stepwise fixation of mutations was consistently observed in the reduced genomes. In summary, this preliminary survey demonstrated that evolution finely tuned the breadth of adaptation correlated with genome reduction.
Collapse
Affiliation(s)
- Masaomi Kurokawa
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Issei Nishimura
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Bei-Wen Ying
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| |
Collapse
|
23
|
Chen Z, Wang X, Song Y, Zeng Q, Zhang Y, Luo H. Prochlorococcus have low global mutation rate and small effective population size. Nat Ecol Evol 2022; 6:183-194. [PMID: 34949817 DOI: 10.1038/s41559-021-01591-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 10/14/2021] [Indexed: 12/27/2022]
Abstract
Prochlorococcus are the most abundant free-living photosynthetic carbon-fixing organisms in the ocean. Prochlorococcus show small genome sizes, low genomic G+C content, reduced DNA repair gene pool and fast evolutionary rates, which are typical features of endosymbiotic bacteria. Nevertheless, their evolutionary mechanisms are believed to be different. Evolution of endosymbiotic bacteria is dominated by genetic drift owing to repeated population bottlenecks, whereas Prochlorococcus are postulated to have extremely large effective population sizes (Ne) and thus drift has rarely been considered. However, accurately extrapolating Ne requires measuring an unbiased global mutation rate through mutation accumulation, which is challenging for Prochlorococcus. Here, we managed this experiment over 1,065 days using Prochlorococcus marinus AS9601, sequenced genomes of 141 mutant lines and determined its mutation rate to be 3.50 × 10-10 per site per generation. Extrapolating Ne additionally requires identifying population boundaries, which we defined using PopCOGenT and over 400 genomes related to AS9601. Accordingly, we calculated its Ne to be 1.68 × 107, which is only reasonably greater than that of endosymbiotic bacteria but surprisingly smaller than that of many free-living bacteria extrapolated using the same approach. Our results therefore suggest that genetic drift is a key driver of Prochlorococcus evolution.
Collapse
Affiliation(s)
- Zhuoyu Chen
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Xiaojun Wang
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Yu Song
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR.,Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Clear Water Bay, Hong Kong SAR
| | - Yao Zhang
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.
| | - Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR. .,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China. .,Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Clear Water Bay, Hong Kong SAR.
| |
Collapse
|
24
|
Suzuki TK, Matsui M, Sriswasdi S, Iwasaki W. Lifestyle Evolution Analysis by Binary-State Speciation and Extinction (BiSSE) Model. Methods Mol Biol 2022; 2569:327-342. [PMID: 36083456 DOI: 10.1007/978-1-0716-2691-7_16] [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: 05/24/2023]
Abstract
Phylogenetic comparative methods (PCMs) combine statistics and evolutionary models to infer the dynamics of trait evolution and diversification that underlie the observed phylogeny. While PCMs have been used to study macro-evolutionary processes and evolutionary transitions of macroorganisms, their application to microbes is still limited. With the abundance of publicly available genomic and trait character data for diverse microbes nowadays, applications of PCMs on these data can provide insights into the fundamental principles that govern microbial evolution. Here, we introduce the Binary-State Speciation and Extinction (BiSSE) model, which is a relatively simple yet powerful approach for analyzing trait evolution. We begin by explaining the theoretical background and intuition behind the BiSSE model. Then, R commands for running the BiSSE model are presented. Finally, we introduce a case study that successfully applied the BiSSE model to investigate generalist and specialist microbial lifestyle evolution.
Collapse
Affiliation(s)
- Takao K Suzuki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Motomu Matsui
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Sira Sriswasdi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Research Affairs, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Computational Molecular Biology Group, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Wataru Iwasaki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan.
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan.
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan.
| |
Collapse
|
25
|
Chuckran PF, Hungate BA, Schwartz E, Dijkstra P. Variation in genomic traits of microbial communities among ecosystems. FEMS MICROBES 2021. [DOI: 10.1093/femsmc/xtab020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
ABSTRACT
Free-living bacteria in nutrient limited environments often exhibit traits which may reduce the cost of reproduction, such as smaller genome size, low GC content and fewer sigma (σ) factor and 16S rRNA gene copies. Despite the potential utility of these traits to detect relationships between microbial communities and ecosystem-scale properties, few studies have assessed these traits on a community-scale. Here, we analysed these traits from publicly available metagenomes derived from marine, soil, host-associated and thermophilic communities. In marine and thermophilic communities, genome size and GC content declined in parallel, consistent with genomic streamlining, with GC content in thermophilic communities generally higher than in marine systems. In contrast, soil communities averaging smaller genomes featured higher GC content and were often from low-carbon environments, suggesting unique selection pressures in soil bacteria. The abundance of specific σ-factors varied with average genome size and ecosystem type. In oceans, abundance of fliA, a σ-factor controlling flagella biosynthesis, was positively correlated with community average genome size—reflecting known trade-offs between nutrient conservation and chemotaxis. In soils, a high abundance of the stress response σ-factor gene rpoS was associated with smaller average genome size and often located in harsh and/or carbon-limited environments—a result which tracks features observed in culture and indicates an increased capacity for stress response in nutrient-poor soils. This work shows how ecosystem-specific constraints are associated with trade-offs which are embedded in the genomic features of bacteria in microbial communities, and which can be detected at the community level, highlighting the importance of genomic features in microbial community analysis.
Collapse
Affiliation(s)
- Peter F Chuckran
- Center for Ecosystem Science and Society (ECOSS) and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - Bruce A Hungate
- Center for Ecosystem Science and Society (ECOSS) and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - Egbert Schwartz
- Center for Ecosystem Science and Society (ECOSS) and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - Paul Dijkstra
- Center for Ecosystem Science and Society (ECOSS) and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, United States of America
| |
Collapse
|
26
|
Zhang H, Sun Y, Zeng Q, Crowe SA, Luo H. Snowball Earth, population bottleneck and Prochlorococcus evolution. Proc Biol Sci 2021; 288:20211956. [PMID: 34784770 PMCID: PMC8596011 DOI: 10.1098/rspb.2021.1956] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/26/2021] [Indexed: 11/12/2022] Open
Abstract
Prochlorococcus are the most abundant photosynthetic organisms in the modern ocean. A massive DNA loss event occurred in their early evolutionary history, leading to highly reduced genomes in nearly all lineages, as well as enhanced efficiency in both nutrient uptake and light absorption. The environmental landscape that shaped this ancient genome reduction, however, remained unknown. Through careful molecular clock analyses, we established that this Prochlorococcus genome reduction occurred during the Neoproterozoic Snowball Earth climate catastrophe. The lethally low temperature and exceedingly dim light during the Snowball Earth event would have inhibited Prochlorococcus growth and proliferation, and caused severe population bottlenecks. These bottlenecks are recorded as an excess of deleterious mutations accumulated across genomic regions and inherited by descendant lineages. Prochlorococcus adaptation to extreme environmental conditions during Snowball Earth intervals can be inferred by tracing the evolutionary paths of genes that encode key metabolic potential. Key metabolic innovation includes modified lipopolysaccharide structure, strengthened peptidoglycan biosynthesis, the replacement of a sophisticated circadian clock with an hourglass-like mechanism that resets daily for dim light adaption and the adoption of ammonia diffusion as an efficient membrane transporter-independent mode of nitrogen acquisition. In this way, the Neoproterozoic Snowball Earth event may have altered the physiological characters of Prochlorococcus, shaping their ecologically vital role as the most abundant primary producers in the modern oceans.
Collapse
Affiliation(s)
- Hao Zhang
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518000, People's Republic of China
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Ying Sun
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR
| | - Sean A. Crowe
- Department of Earth Sciences, School of Biological Sciences, and Swire Institute for Marine Science (SWIMS), University of Hong Kong, Pokfulam Road, Hong Kong SAR
| | - Haiwei Luo
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518000, People's Republic of China
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| |
Collapse
|
27
|
Kinjo Y, Lo N, Martín PV, Tokuda G, Pigolotti S, Bourguignon T. Enhanced Mutation Rate, Relaxed Selection, and the "Domino Effect" are associated with Gene Loss in Blattabacterium, A Cockroach Endosymbiont. Mol Biol Evol 2021; 38:3820-3831. [PMID: 34426845 PMCID: PMC8382890 DOI: 10.1093/molbev/msab159] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Intracellular endosymbionts have reduced genomes that progressively lose genes at a timescale of tens of million years. We previously reported that gene loss rate is linked to mutation rate in Blattabacterium, however, the mechanisms causing gene loss are not yet fully understood. Here, we carried out comparative genomic analyses on the complete genome sequences of a representative set of 67 Blattabacterium strains, with sizes ranging between 511 and 645 kb. We found that 200 of the 566 analyzed protein-coding genes were lost in at least one lineage of Blattabacterium, with the most extreme case being one gene that was lost independently in 24 lineages. We found evidence for three mechanisms influencing gene loss in Blattabacterium. First, gene loss rates were found to increase exponentially with the accumulation of substitutions. Second, genes involved in vitamin and amino acid metabolism experienced relaxed selection in Cryptocercus and Mastotermes, possibly triggered by their vertically inherited gut symbionts. Third, we found evidence of epistatic interactions among genes leading to a "domino effect" of gene loss within pathways. Our results highlight the complexity of the process of genome erosion in an endosymbiont.
Collapse
Affiliation(s)
- Yukihiro Kinjo
- Okinawa Institute of Science & Technology Graduate University, Tancha, Onna-son, Okinawa, Japan
| | - Nathan Lo
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - Paula Villa Martín
- Okinawa Institute of Science & Technology Graduate University, Tancha, Onna-son, Okinawa, Japan
| | - Gaku Tokuda
- Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Simone Pigolotti
- Okinawa Institute of Science & Technology Graduate University, Tancha, Onna-son, Okinawa, Japan
| | - Thomas Bourguignon
- Okinawa Institute of Science & Technology Graduate University, Tancha, Onna-son, Okinawa, Japan
| |
Collapse
|
28
|
Browne HP, Almeida A, Kumar N, Vervier K, Adoum AT, Viciani E, Dawson NJR, Forster SC, Cormie C, Goulding D, Lawley TD. Host adaptation in gut Firmicutes is associated with sporulation loss and altered transmission cycle. Genome Biol 2021; 22:204. [PMID: 34348764 PMCID: PMC8340488 DOI: 10.1186/s13059-021-02428-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 07/01/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Human-to-human transmission of symbiotic, anaerobic bacteria is a fundamental evolutionary adaptation essential for membership of the human gut microbiota. However, despite its importance, the genomic and biological adaptations underpinning symbiont transmission remain poorly understood. The Firmicutes are a dominant phylum within the intestinal microbiota that are capable of producing resistant endospores that maintain viability within the environment and germinate within the intestine to facilitate transmission. However, the impact of host transmission on the evolutionary and adaptive processes within the intestinal microbiota remains unknown. RESULTS We analyze 1358 genomes of Firmicutes bacteria derived from host and environment-associated habitats. Characterization of genomes as spore-forming based on the presence of sporulation-predictive genes reveals multiple losses of sporulation in many distinct lineages. Loss of sporulation in gut Firmicutes is associated with features of host-adaptation such as genome reduction and specialized metabolic capabilities. Consistent with these data, analysis of 9966 gut metagenomes from adults around the world demonstrates that bacteria now incapable of sporulation are more abundant within individuals but less prevalent in the human population compared to spore-forming bacteria. CONCLUSIONS Our results suggest host adaptation in gut Firmicutes is an evolutionary trade-off between transmission range and colonization abundance. We reveal host transmission as an underappreciated process that shapes the evolution, assembly, and functions of gut Firmicutes.
Collapse
Affiliation(s)
- Hilary P Browne
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK.
| | - Alexandre Almeida
- Wellcome Sanger Institute, Hinxton, UK
- European Bioinformatics Institute, Hinxton, UK
| | - Nitin Kumar
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | - Kevin Vervier
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | | | - Elisa Viciani
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | - Nicholas J R Dawson
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | - Samuel C Forster
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria, 3800, Australia
| | | | | | - Trevor D Lawley
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK.
| |
Collapse
|
29
|
McCutcheon JP. The Genomics and Cell Biology of Host-Beneficial Intracellular Infections. Annu Rev Cell Dev Biol 2021; 37:115-142. [PMID: 34242059 DOI: 10.1146/annurev-cellbio-120219-024122] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microbes gain access to eukaryotic cells as food for bacteria-grazing protists, for host protection by microbe-killing immune cells, or for microbial benefit when pathogens enter host cells to replicate. But microbes can also gain access to a host cell and become an important-often required-beneficial partner. The oldest beneficial microbial infections are the ancient eukaryotic organelles now called the mitochondrion and plastid. But numerous other host-beneficial intracellular infections occur throughout eukaryotes. Here I review the genomics and cell biology of these interactions with a focus on intracellular bacteria. The genomes of host-beneficial intracellular bacteria have features that span a previously unfilled gap between pathogens and organelles. Host cell adaptations to allow the intracellular persistence of beneficial bacteria are found along with evidence for the microbial manipulation of host cells, but the cellular mechanisms of beneficial bacterial infections are not well understood. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- John P McCutcheon
- Biodesign Center for Mechanisms of Evolution, School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA;
| |
Collapse
|
30
|
Feng X, Chu X, Qian Y, Henson MW, Lanclos VC, Qin F, Barnes S, Zhao Y, Thrash JC, Luo H. Mechanisms driving genome reduction of a novel Roseobacter lineage. ISME JOURNAL 2021; 15:3576-3586. [PMID: 34145391 DOI: 10.1038/s41396-021-01036-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 01/21/2023]
Abstract
Members of the marine Roseobacter group are key players in the global carbon and sulfur cycles. While over 300 species have been described, only 2% possess reduced genomes (mostly 3-3.5 Mbp) compared to an average roseobacter (>4 Mbp). These taxonomic minorities are phylogenetically diverse but form a Pelagic Roseobacter Cluster (PRC) at the genome content level. Here, we cultivated eight isolates constituting a novel Roseobacter lineage which we named 'CHUG'. Metagenomic and metatranscriptomic read recruitment analyses showed that CHUG members are globally distributed and active in marine pelagic environments. CHUG members possess some of the smallest genomes (~2.6 Mb) among all known roseobacters, but they do not exhibit canonical features of typical bacterioplankton lineages theorized to have undergone genome streamlining processes, like higher coding density, fewer paralogues and rarer pseudogenes. While CHUG members form a genome content cluster with traditional PRC members, they show important differences. Unlike other PRC members, neither the relative abundances of CHUG members nor their relative gene expression levels are correlated with chlorophyll a concentration across the global samples. CHUG members cannot utilize most phytoplankton-derived metabolites or synthesize vitamin B12, a key metabolite mediating the roseobacter-phytoplankton interactions. This combination of features is evidence for the hypothesis that CHUG members may have evolved a free-living lifestyle decoupled from phytoplankton. This ecological transition was accompanied by the loss of signature genes involved in roseobacter-phytoplankton symbiosis, suggesting that relaxation of purifying selection owing to lifestyle shift is likely an important driver of genome reduction in CHUG.
Collapse
Affiliation(s)
- Xiaoyuan Feng
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Xiao Chu
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong
| | - Yang Qian
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong
| | - Michael W Henson
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA.,Department of Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - V Celeste Lanclos
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Fang Qin
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Shelby Barnes
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Yanlin Zhao
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - J Cameron Thrash
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong. .,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.
| |
Collapse
|
31
|
Marais GAB, Batut B, Daubin V. Genome Evolution: Mutation Is the Main Driver of Genome Size in Prokaryotes. Curr Biol 2021; 30:R1083-R1085. [PMID: 33022240 DOI: 10.1016/j.cub.2020.07.093] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Despite intense research on genome architecture since the 2000s, genome-size evolution in prokaryotes has remained puzzling. Using a phylogenetic approach, a new study found that increased mutation rate is associated with gene loss and reduced genome size in prokaryotes.
Collapse
Affiliation(s)
- Gabriel A B Marais
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, F-69622 Villeurbanne, France.
| | - Bérénice Batut
- Albert-Ludwigs-University Freiburg, Department of Computer Science, 79110 Freiburg, Germany
| | - Vincent Daubin
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, F-69622 Villeurbanne, France
| |
Collapse
|
32
|
Ionescu D, Zoccarato L, Zaduryan A, Schorn S, Bizic M, Pinnow S, Cypionka H, Grossart HP. Heterozygous, Polyploid, Giant Bacterium, Achromatium, Possesses an Identical Functional Inventory Worldwide across Drastically Different Ecosystems. Mol Biol Evol 2021; 38:1040-1059. [PMID: 33169788 PMCID: PMC7947748 DOI: 10.1093/molbev/msaa273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Achromatium is large, hyperpolyploid and the only known heterozygous bacterium. Single cells contain approximately 300 different chromosomes with allelic diversity far exceeding that typically harbored by single bacteria genera. Surveying all publicly available sediment sequence archives, we show that Achromatium is common worldwide, spanning temperature, salinity, pH, and depth ranges normally resulting in bacterial speciation. Although saline and freshwater Achromatium spp. appear phylogenetically separated, the genus Achromatium contains a globally identical, complete functional inventory regardless of habitat. Achromatium spp. cells from differing ecosystems (e.g., from freshwater to saline) are, unexpectedly, equally functionally equipped but differ in gene expression patterns by transcribing only relevant genes. We suggest that environmental adaptation occurs by increasing the copy number of relevant genes across the cell's hundreds of chromosomes, without losing irrelevant ones, thus maintaining the ability to survive in any ecosystem type. The functional versatility of Achromatium and its genomic features reveal alternative genetic and evolutionary mechanisms, expanding our understanding of the role and evolution of polyploidy in bacteria while challenging the bacterial species concept and drivers of bacterial speciation.
Collapse
Affiliation(s)
- Danny Ionescu
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany
- Berlin Brandenburg Institute of Biodiversity, Berlin, Germany
| | - Luca Zoccarato
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany
| | - Artur Zaduryan
- Department of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Sina Schorn
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Mina Bizic
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany
- Berlin Brandenburg Institute of Biodiversity, Berlin, Germany
| | - Solvig Pinnow
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany
| | - Heribert Cypionka
- Institute for Chemistry and Biology of the Marine Environment, Oldenburg, Germany
| | - Hans-Peter Grossart
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany
- Berlin Brandenburg Institute of Biodiversity, Berlin, Germany
- Institute of Biochemistry and Biology, Potsdam University, Potsdam, Germany
| |
Collapse
|
33
|
Hoque N, Islam SKS, Uddin MN, Arif M, Haque AKMZ, Neogi SB, Hossain MM, Yamasaki S, Kabir SML. Prevalence, Risk Factors, and Molecular Detection of Campylobacter in Farmed Cattle of Selected Districts in Bangladesh. Pathogens 2021; 10:313. [PMID: 33800065 PMCID: PMC7998914 DOI: 10.3390/pathogens10030313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 11/16/2022] Open
Abstract
A cross-sectional survey was conducted in selected districts of Bangladesh to estimate prevalence, risk factors, and molecular detection of Campylobacter isolates from 540 farmed cattle of 90 herds. As an individual sample, 540 feces, and as a pooled sample, 180 milk samples, 90 feed samples, 90 water samples, 90 manure samples, and 90 animal attendants' hand-rinse water were collected and tested via culture, biochemical, and molecular assays. A pretested semi-structured questionnaire was used to collect herd-level data on risk factors with the herd owners. The herd-level data on risk factors were analyzed through univariate and multivariate analyses, and a p-value <0.05 was considered statistically significant for all analyses. Overall, farm-level prevalence of bovine Campylobacter was enumerated to be 53.3% (95% confidence interval [CI]: 42.5-63.9%). The feces sample was found to be a high level of contamination of 30.9% (95% CI: 27-35%) followed by the manure swab (pooled) at 15.6% (95% CI: 8.8-24.7%). Campylobacter jejuni was documented as an abundant species (12.6%), followed by Campylobacter coli (5.1%), and Campylobacter fetus (0.3%). Older farms (>5 years of age), no/minimum cleaning and disinfection practices, along with animal roaming outside of the farm, were documented as significant risk factors for farm-level Campylobacter occurrence. Evidence-based control measures need to be taken through stringent biosecurity and hygienic measurement to lessen the load of the Campylobacter pathogen in the farm environment and prevent further transmission to animals and humans.
Collapse
Affiliation(s)
- Nazmul Hoque
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| | - SK Shaheenur Islam
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| | - Md. Nasir Uddin
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| | - Mohammad Arif
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| | - A. K. M. Ziaul Haque
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| | - Sucharit Basu Neogi
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan; (S.B.N.); (S.Y.)
| | - Md. Mehedi Hossain
- Program Specialist (Livestock), Krishi Gobeshona Foundation (KGF), Dhaka 1215, Bangladesh;
| | - Shinji Yamasaki
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan; (S.B.N.); (S.Y.)
| | - S. M. Lutful Kabir
- Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh; (N.H.); (S.S.I.); (M.N.U.); (M.A.); (A.K.M.Z.H.)
| |
Collapse
|
34
|
Huang H, Qi M, Liu Y, Wang H, Wang X, Qiu Y, Lu Z. Thiamine-Mediated Cooperation Between Auxotrophic Rhodococcus ruber ZM07 and Escherichia coli K12 Drives Efficient Tetrahydrofuran Degradation. Front Microbiol 2020; 11:594052. [PMID: 33362743 PMCID: PMC7758286 DOI: 10.3389/fmicb.2020.594052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/16/2020] [Indexed: 11/13/2022] Open
Abstract
Tetrahydrofuran (THF) is a universal solvent widely used in the synthesis of chemicals and pharmaceuticals. As a refractory organic contaminant, it can only be degraded by a small group of microbes. In this study, a thiamine auxotrophic THF-degrading bacterium, Rhodococcus ruber ZM07, was isolated from an enrichment culture H-1. It was cocultured with Escherichia coli K12 (which cannot degrade THF but can produce thiamine) and/or Escherichia coli K12ΔthiE (which can neither degrade THF nor produce thiamine) with or without exogenous thiamine. This study aims to understand the interaction mechanisms between ZM07 and K12. We found that K12 accounted for 30% of the total when cocultured and transferred with ZM07 in thiamine-free systems; in addition, in the three-strain (ZM07, K12, and K12ΔthiE) cocultured system without thiamine, K12ΔthiE disappeared in the 8th transfer, while K12 could still stably exist (the relative abundance remained at approximately 30%). The growth of K12 was significantly inhibited in the thiamine-rich system. Its proportion was almost below 4% after the fourth transfer in both the two-strain (ZM07 and K12) and three-strain (ZM07, K12, and K12ΔthiE) systems; K12ΔthiE’s percentage was higher than K12’s in the three-strain (ZM07, K12, and K12ΔthiE) cocultured system with exogenous thiamine, and both represented only a small proportion (less than 1% by the fourth transfer). The results of the coculture of K12 and K12ΔthiE in thiamine-free medium indicated that intraspecific competition between them may be one of the main reasons for the extinction of K12ΔthiE in the three-strain (ZM07, K12, and K12ΔthiE) system without exogenous thiamine. Furthermore, we found that ZM07 could cooperate with K12 through extracellular metabolites exchanges without physical contact. This study provides novel insight into how microbes cooperate and compete with one another during THF degradation.
Collapse
Affiliation(s)
- Hui Huang
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Minbo Qi
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yiming Liu
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Haixia Wang
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Xuejun Wang
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yiyang Qiu
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Zhenmei Lu
- MOE Laboratory of Biosystem Homeostasis and Protection, Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China
| |
Collapse
|
35
|
Moya A, Oliver JL, Verdú M, Delaye L, Arnau V, Bernaola-Galván P, de la Fuente R, Díaz W, Gómez-Martín C, González FM, Latorre A, Lebrón R, Román-Roldán R. Driven progressive evolution of genome sequence complexity in Cyanobacteria. Sci Rep 2020; 10:19073. [PMID: 33149190 PMCID: PMC7643063 DOI: 10.1038/s41598-020-76014-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 10/22/2020] [Indexed: 02/07/2023] Open
Abstract
Progressive evolution, or the tendency towards increasing complexity, is a controversial issue in biology, which resolution entails a proper measurement of complexity. Genomes are the best entities to address this challenge, as they encode the historical information of a species' biotic and environmental interactions. As a case study, we have measured genome sequence complexity in the ancient phylum Cyanobacteria. To arrive at an appropriate measure of genome sequence complexity, we have chosen metrics that do not decipher biological functionality but that show strong phylogenetic signal. Using a ridge regression of those metrics against root-to-tip distance, we detected positive trends towards higher complexity in three of them. Lastly, we applied three standard tests to detect if progressive evolution is passive or driven-the minimum, ancestor-descendant, and sub-clade tests. These results provide evidence for driven progressive evolution at the genome-level in the phylum Cyanobacteria.
Collapse
Affiliation(s)
- Andrés Moya
- Institute of Integrative Systems Biology (I2Sysbio), University of València and Consejo Superior de Investigaciones Científicas (CSIC), 46980, Valencia, Spain.
- Foundation for the Promotion of Sanitary and Biomedical Research of Valencian Community (FISABIO), 46020, Valencia, Spain.
- CIBER in Epidemiology and Public Health, 28029, Madrid, Spain.
| | - José L Oliver
- Department of Genetics, Faculty of Sciences, University of Granada, 18071, Granada, Spain
- Laboratory of Bioinformatics, Institute of Biotechnology, Center of Biomedical Research, 18100, Granada, Spain
| | - Miguel Verdú
- Centro de Investigaciones sobre Desertificación, Consejo Superior de Investigaciones Científicas (CSIC), University of València and Generalitat Valenciana, 46113, Valencia, Spain
| | - Luis Delaye
- Department of Genetic Engineering, CINVESTAV, 36821, Irapuato, Mexico
| | - Vicente Arnau
- Institute of Integrative Systems Biology (I2Sysbio), University of València and Consejo Superior de Investigaciones Científicas (CSIC), 46980, Valencia, Spain
| | - Pedro Bernaola-Galván
- Department of Applied Physics II and Institute Carlos I for Theoretical and Computational Physics, University of Málaga, 29071, Málaga, Spain
| | - Rebeca de la Fuente
- Institute for Cross-Disciplinary Physics and Complex Systems (IFISC), Consejo Superior de Investigaciones Científicas (CSIC) and University of Balearic Islands, 07122, Palma de Mallorca, Spain
| | - Wladimiro Díaz
- Institute of Integrative Systems Biology (I2Sysbio), University of València and Consejo Superior de Investigaciones Científicas (CSIC), 46980, Valencia, Spain
| | - Cristina Gómez-Martín
- Department of Genetics, Faculty of Sciences, University of Granada, 18071, Granada, Spain
- Laboratory of Bioinformatics, Institute of Biotechnology, Center of Biomedical Research, 18100, Granada, Spain
| | | | - Amparo Latorre
- Institute of Integrative Systems Biology (I2Sysbio), University of València and Consejo Superior de Investigaciones Científicas (CSIC), 46980, Valencia, Spain
- Foundation for the Promotion of Sanitary and Biomedical Research of Valencian Community (FISABIO), 46020, Valencia, Spain
- CIBER in Epidemiology and Public Health, 28029, Madrid, Spain
| | - Ricardo Lebrón
- Department of Genetics, Faculty of Sciences, University of Granada, 18071, Granada, Spain
- Laboratory of Bioinformatics, Institute of Biotechnology, Center of Biomedical Research, 18100, Granada, Spain
| | - Ramón Román-Roldán
- Department of Applied Physics, University of Granada, 18071, Granada, Spain
| |
Collapse
|
36
|
Bourguignon T, Kinjo Y, Villa-Martín P, Coleman NV, Tang Q, Arab DA, Wang Z, Tokuda G, Hongoh Y, Ohkuma M, Ho SY, Pigolotti S, Lo N. Increased Mutation Rate Is Linked to Genome Reduction in Prokaryotes. Curr Biol 2020; 30:3848-3855.e4. [DOI: 10.1016/j.cub.2020.07.034] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/27/2020] [Accepted: 07/09/2020] [Indexed: 01/08/2023]
|
37
|
Bohlin J, Rose B, Brynildsrud O, Birgitte Freiesleben De Blasio. A simple stochastic model describing genomic evolution over time of GC content in microbial symbionts. J Theor Biol 2020; 503:110389. [PMID: 32634385 DOI: 10.1016/j.jtbi.2020.110389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 04/21/2020] [Accepted: 06/24/2020] [Indexed: 11/29/2022]
Abstract
An organism's genomic base composition is usually summarized by its AT or GC content due to Chargaff's parity laws. Variation in prokaryotic GC content can be substantial between taxa but is generally small within microbial genomes. This variation has been found to correlate with both phylogeny and environmental factors. Since novel single-nucleotide polymorphisms (SNPs) within genomes are at least partially linked to the environment through natural selection, SNP GC content can be considered a compound measure of an organism's environmental influences, lifestyle, phylogeny as well as other more or less random processes. While there are several models describing genomic GC content few, if any, consider AT/GC mutation rates subjected to random perturbations. We present a mathematical model that describes how GC content in microbial genomes evolves over time as a function of the AT → GC and GC → AT mutation rates with Gaussian white noise disturbances. The model, which is suited specifically to non-recombining vertically transmitted prokaryotic symbionts, suggests that small differences in the AT/GC mutation rates can lead to profound differences in outcome due to the ensuing stochastic process. In other words, the model indicates that time to extinction could be a consequence of the mutation rate trajectory on which the symbiont embarked early on in its evolutionary history.
Collapse
Affiliation(s)
- Jon Bohlin
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway; Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway; Department of Production Animals, Faculty of Veterinary Medicine, Norwegian University of Life Science, Oslo, Norway
| | - Brittany Rose
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway; Department of Biostatistics, Oslo Centre for Biostatistics and Epidemiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Ola Brynildsrud
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway; Department of Production Animals, Faculty of Veterinary Medicine, Norwegian University of Life Science, Oslo, Norway
| | - Birgitte Freiesleben De Blasio
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway; Department of Biostatistics, Oslo Centre for Biostatistics and Epidemiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| |
Collapse
|
38
|
Touchon M, Perrin A, de Sousa JAM, Vangchhia B, Burn S, O’Brien CL, Denamur E, Gordon D, Rocha EPC. Phylogenetic background and habitat drive the genetic diversification of Escherichia coli. PLoS Genet 2020; 16:e1008866. [PMID: 32530914 PMCID: PMC7314097 DOI: 10.1371/journal.pgen.1008866] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/24/2020] [Accepted: 05/18/2020] [Indexed: 12/15/2022] Open
Abstract
Escherichia coli is mostly a commensal of birds and mammals, including humans, where it can act as an opportunistic pathogen. It is also found in water and sediments. We investigated the phylogeny, genetic diversification, and habitat-association of 1,294 isolates representative of the phylogenetic diversity of more than 5,000 isolates from the Australian continent. Since many previous studies focused on clinical isolates, we investigated mostly other isolates originating from humans, poultry, wild animals and water. These strains represent the species genetic diversity and reveal widespread associations between phylogroups and isolation sources. The analysis of strains from the same sequence types revealed very rapid change of gene repertoires in the very early stages of divergence, driven by the acquisition of many different types of mobile genetic elements. These elements also lead to rapid variations in genome size, even if few of their genes rise to high frequency in the species. Variations in genome size are associated with phylogroup and isolation sources, but the latter determine the number of MGEs, a marker of recent transfer, suggesting that gene flow reinforces the association of certain genetic backgrounds with specific habitats. After a while, the divergence of gene repertoires becomes linear with phylogenetic distance, presumably reflecting the continuous turnover of mobile element and the occasional acquisition of adaptive genes. Surprisingly, the phylogroups with smallest genomes have the highest rates of gene repertoire diversification and fewer but more diverse mobile genetic elements. This suggests that smaller genomes are associated with higher, not lower, turnover of genetic information. Many of these genomes are from freshwater isolates and have peculiar traits, including a specific capsule, suggesting adaptation to this environment. Altogether, these data contribute to explain why epidemiological clones tend to emerge from specific phylogenetic groups in the presence of pervasive horizontal gene transfer across the species. Previous large scale studies on the evolution of E. coli focused on clinical isolates emphasizing virulence and antibiotic resistance in medically important lineages. Yet, most E. coli strains are either human commensals or not associated with humans at all. Here, we analyzed a large collection of non-clinical isolates of the species to assess the mechanisms of gene repertoire diversification in the light of isolation sources and phylogeny. We show that gene repertoires evolve so rapidly by the high turnover of mobile genetic elements that epidemiologically indistinguishable strains can be phenotypically extremely heterogeneous, illustrating the velocity of bacterial adaptation and the importance of accounting for the information on the whole genome at the epidemiological scale. Phylogeny and habitat shape the genetic diversification of E. coli to similar extents. Surprisingly, freshwater strains seem specifically adapted to this environment, breaking the paradigm that E. coli environmental isolates are systematically fecal contaminations. As a consequence, the evolution of this species is also shaped by environmental habitats, and it may diversify by acquiring genes and mobile elements from environmental bacteria (and not just from gut bacteria). This may facilitate the acquisition of virulence factors and antibiotic resistance in the strains that become pathogenic.
Collapse
Affiliation(s)
- Marie Touchon
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, 25-28 rue Dr Roux, Paris, 75015, France
- * E-mail:
| | - Amandine Perrin
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, 25-28 rue Dr Roux, Paris, 75015, France
- Sorbonne Université, Collège doctoral, F-75005 Paris, France
| | - Jorge André Moura de Sousa
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, 25-28 rue Dr Roux, Paris, 75015, France
| | - Belinda Vangchhia
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, ACT, Australia
- Department of Veterinary Microbiology, College of Veterinary Sciences & Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Samantha Burn
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Claire L. O’Brien
- School of Medicine, University of Wollongong, Northfields Ave Wollongong, Australia
| | - Erick Denamur
- Université de Paris, IAME, UMR 1137, INSERM, Paris, 75018, France
- AP-HP, Laboratoire de Génétique Moléculaire, Hôpital Bichat, 75018, Paris, France
| | - David Gordon
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Eduardo PC Rocha
- Microbial Evolutionary Genomics, Institut Pasteur, CNRS, UMR3525, 25-28 rue Dr Roux, Paris, 75015, France
| |
Collapse
|
39
|
Männle D, McKinnie SMK, Mantri SS, Steinke K, Lu Z, Moore BS, Ziemert N, Kaysser L. Comparative Genomics and Metabolomics in the Genus Nocardia. mSystems 2020; 5:e00125-20. [PMID: 32487740 PMCID: PMC7413640 DOI: 10.1128/msystems.00125-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/13/2020] [Indexed: 01/22/2023] Open
Abstract
Using automated genome analysis tools, it is often unclear to what degree genetic variability in homologous biosynthetic pathways relates to structural variation. This hampers strain prioritization and compound identification and can lead to overinterpretation of chemical diversity. Here, we assessed the metabolic potential of Nocardia, an underinvestigated actinobacterial genus that is known to comprise opportunistic human pathogens. Our analysis revealed a plethora of putative biosynthetic gene clusters of various classes, including polyketide, nonribosomal peptide, and terpenoid pathways. Furthermore, we used the highly conserved biosynthetic pathway for nocobactin-like siderophores to investigate how gene cluster differences correlate to structural differences in the produced compounds. Sequence similarity networks generated by BiG-SCAPE (Biosynthetic Gene Similarity Clustering and Prospecting Engine) showed the presence of several distinct gene cluster families. Metabolic profiling of selected Nocardia strains using liquid chromatography-mass spectrometry (LC-MS) metabolomics data, nuclear magnetic resonance (NMR) spectroscopy, and GNPS (Global Natural Product Social molecular networking) revealed that nocobactin-like biosynthetic gene cluster (BGC) families above a BiG-SCAPE threshold of 70% can be assigned to distinct structural types of nocobactin-like siderophores.IMPORTANCE Our work emphasizes that Nocardia represent a prolific source for natural products rivaling better-characterized genera such as Streptomyces or Amycolatopsis Furthermore, we showed that large-scale analysis of biosynthetic gene clusters using similarity networks with high stringency allows the distinction and prediction of natural product structural variations. This will facilitate future genomics-driven drug discovery campaigns.
Collapse
Affiliation(s)
- Daniel Männle
- Pharmaceutical Biology, Eberhard Karls University Tübingen, Tübingen, Germany
- German Centre for Infection Research (DZIF), Tübingen, Germany
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), Microbiology and Biotechnology, University of Tübingen, Tübingen, Germany
| | - Shaun M K McKinnie
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California, USA
| | - Shrikant S Mantri
- German Centre for Infection Research (DZIF), Tübingen, Germany
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), Microbiology and Biotechnology, University of Tübingen, Tübingen, Germany
| | - Katharina Steinke
- German Centre for Infection Research (DZIF), Tübingen, Germany
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), Microbiology and Biotechnology, University of Tübingen, Tübingen, Germany
| | - Zeyin Lu
- Pharmaceutical Biology, Eberhard Karls University Tübingen, Tübingen, Germany
- German Centre for Infection Research (DZIF), Tübingen, Germany
| | - Bradley S Moore
- Scripps Institution of Oceanography, University of California, San Diego, California, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California, USA
| | - Nadine Ziemert
- German Centre for Infection Research (DZIF), Tübingen, Germany
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), Microbiology and Biotechnology, University of Tübingen, Tübingen, Germany
| | - Leonard Kaysser
- Pharmaceutical Biology, Eberhard Karls University Tübingen, Tübingen, Germany
- German Centre for Infection Research (DZIF), Tübingen, Germany
| |
Collapse
|
40
|
Xue CX, Zhang H, Lin HY, Sun Y, Luo D, Huang Y, Zhang XH, Luo H. Ancestral niche separation and evolutionary rate differentiation between sister marine flavobacteria lineages. Environ Microbiol 2020; 22:3234-3247. [PMID: 32390223 DOI: 10.1111/1462-2920.15065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/05/2020] [Accepted: 05/07/2020] [Indexed: 12/30/2022]
Abstract
Marine flavobacteria are specialists for polysaccharide degradation. They dominate in habitats enriched with polysaccharides, but are also prevalent in pelagic environments where polysaccharides are less available. These niches are likely occupied by distinct lineages, but evolutionary processes underlying their niche differentiation remain elusive. Here, genomic analyses and physiological assays indicate that the sister flavobacteria lineages Leeuwenhoekiella and Nonlabens likely explore polysaccharide-rich macroalgae and polysaccharide-poor pelagic niches respectively. Phylogenomic analyses inferred that the niche separation likely occurred anciently and coincided with increased sequence evolutionary rate in Nonlabens compared with Leeuwenhoekiella. Further analyses ruled out the known mechanisms likely driving evolutionary rate acceleration, including reduced selection efficiency, decreased generation time and increased mutation rate. In particular, the mutation rates were determined using an unbiased experimental method, which measures the present-day populations and may not reflect ancestral populations. These data collectively lead to a new hypothesis that an ancestral and transient mutation rate increase resulted in evolutionary rate increase in Nonlabens. This hypothesis was supported by inferring that gains and losses of genes involved in SOS response, a mechanism known to drive transiently increased mutation rate, coincided with evolutionary rate acceleration. Our analyses highlight the evolutionary mechanisms underlying niche differentiation of flavobacteria lineages.
Collapse
Affiliation(s)
- Chun-Xu Xue
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.,Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Hao Zhang
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - He-Yu Lin
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Ying Sun
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Danli Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Yongjie Huang
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Xiao-Hua Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Haiwei Luo
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518000, China
| |
Collapse
|
41
|
Agricultural intensification and the evolution of host specialism in the enteric pathogen Campylobacter jejuni. Proc Natl Acad Sci U S A 2020; 117:11018-11028. [PMID: 32366649 PMCID: PMC7245135 DOI: 10.1073/pnas.1917168117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Modern agriculture has dramatically changed the distribution of animal species on Earth. Changes to host ecology have a major impact on the microbiota, potentially increasing the risk of zoonotic pathogens being transmitted to humans, but the impact of intensive livestock production on host-associated bacteria has rarely been studied. Here, we use large isolate collections and comparative genomics techniques, linked to phenotype studies, to understand the timescale and genomic adaptations associated with the proliferation of the most common food-born bacterial pathogen (Campylobacter jejuni) in the most prolific agricultural mammal (cattle). Our findings reveal the emergence of cattle specialist C. jejuni lineages from a background of host generalist strains that coincided with the dramatic rise in cattle numbers in the 20th century. Cattle adaptation was associated with horizontal gene transfer and significant gene gain and loss. This may be related to differences in host diet, anatomy, and physiology, leading to the proliferation of globally disseminated cattle specialists of major public health importance. This work highlights how genomic plasticity can allow important zoonotic pathogens to exploit altered niches in the face of anthropogenic change and provides information for mitigating some of the risks posed by modern agricultural systems.
Collapse
|
42
|
West EE, Kunz N, Kemper C. Complement and human T cell metabolism: Location, location, location. Immunol Rev 2020; 295:68-81. [PMID: 32166778 PMCID: PMC7261501 DOI: 10.1111/imr.12852] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 02/19/2020] [Accepted: 02/25/2020] [Indexed: 12/26/2022]
Abstract
The complement system represents one of the evolutionary oldest arms of our immune system and is commonly recognized as a liver-derived and serum-active system critical for providing protection against invading pathogens. Recent unexpected findings, however, have defined novel and rather "uncommon" locations and activities of complement. Specifically, the discovery of an intracellularly active complement system-the complosome-and its key role in the regulation of cell metabolic pathways that underly normal human T cell responses have taught us that there is still much to be discovered about this system. Here, we summarize the current knowledge about the emerging functions of the complosome in T cell metabolism. We further place complosome activities among the non-canonical roles of other intracellular innate danger sensing systems and argue that a "location-centric" view of complement evolution could logically justify its close connection with the regulation of basic cell physiology.
Collapse
Affiliation(s)
- Erin E. West
- Complement and Inflammation Research Section, National Heart, Lung and Blood Institute, Bethesda, MD, USA
| | - Natalia Kunz
- Complement and Inflammation Research Section, National Heart, Lung and Blood Institute, Bethesda, MD, USA
| | - Claudia Kemper
- Complement and Inflammation Research Section, National Heart, Lung and Blood Institute, Bethesda, MD, USA
- Faculty of Life Sciences and Medicine, King’s College London, London, UK
- Institute for Systemic Inflammation Research, University of Lübeck, Lübeck, Germany
| |
Collapse
|
43
|
Giri S, Shitut S, Kost C. Harnessing ecological and evolutionary principles to guide the design of microbial production consortia. Curr Opin Biotechnol 2020; 62:228-238. [DOI: 10.1016/j.copbio.2019.12.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/27/2019] [Accepted: 12/13/2019] [Indexed: 02/06/2023]
|
44
|
Martinez-Gutierrez CA, Aylward FO. Strong Purifying Selection Is Associated with Genome Streamlining in Epipelagic Marinimicrobia. Genome Biol Evol 2020; 11:2887-2894. [PMID: 31539038 PMCID: PMC6798728 DOI: 10.1093/gbe/evz201] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2019] [Indexed: 12/21/2022] Open
Abstract
Marine microorganisms inhabiting nutrient-depleted waters play critical roles in global biogeochemical cycles due to their abundance and broad distribution. Many of these microbes share similar genomic features including small genome size, low % G + C content, short intergenic regions, and low nitrogen content in encoded amino acid residue side chains (N-ARSC), but the evolutionary drivers of these characteristics are unclear. Here, we compared the strength of purifying selection across the Marinimicrobia, a candidate phylum which encompasses a broad range of phylogenetic groups with disparate genomic features, by estimating the ratio of nonsynonymous and synonymous substitutions (dN/dS) in conserved marker genes. Our analysis reveals that epipelagic Marinimicrobia that exhibit features consistent with genome streamlining have significantly lower dN/dS values when compared with their mesopelagic counterparts. We also found a significant positive correlation between median dN/dS values and % G + C content, N-ARSC, and intergenic region length. We did not identify a significant correlation between dN/dS ratios and estimated genome size, suggesting the strength of selection is not a primary factor shaping genome size in this group. Our findings are generally consistent with genome streamlining theory, which postulates that many genomic features of abundant epipelagic bacteria are the result of adaptation to oligotrophic nutrient conditions. Our results are also in agreement with previous findings that genome streamlining is common in epipelagic waters, suggesting that microbes inhabiting this region of the ocean have been shaped by strong selection together with prevalent nutritional constraints characteristic of this environment.
Collapse
Affiliation(s)
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia
| |
Collapse
|
45
|
Liard V, Parsons DP, Rouzaud-Cornabas J, Beslon G. The Complexity Ratchet: Stronger than Selection, Stronger than Evolvability, Weaker than Robustness. ARTIFICIAL LIFE 2020; 26:38-57. [PMID: 32027534 DOI: 10.1162/artl_a_00312] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Using the in silico experimental evolution platform Aevol, we have tested the existence of a complexity ratchet by evolving populations of digital organisms under environmental conditions in which simple organisms can very well thrive and reproduce. We observed that in most simulations, organisms become complex although such organisms are a lot less fit than simple ones and have no robustness or evolvability advantage. This excludes selection from the set of possible explanations for the evolution of complexity. However, complementary experiments showed that selection is nevertheless necessary for complexity to evolve, also excluding non-selective effects. Analyzing the long-term fate of complex organisms, we showed that complex organisms almost never switch back to simplicity despite the potential fitness benefit. On the contrary, they consistently accumulate complexity in the long term, meanwhile slowly increasing their fitness but never overtaking that of simple organisms. This suggests the existence of a complexity ratchet powered by negative epistasis: Mutations leading to simple solutions, which are favorable at the beginning of the simulation, become deleterious after other mutations-leading to complex solutions-have been fixed. This also suggests that this complexity ratchet cannot be beaten by selection, but that it can be overthrown by robustness because of the constraints it imposes on the coding capacity of the genome.
Collapse
Affiliation(s)
- Vincent Liard
- Inria Beagle Team
- Université de Lyon
- INSA-Lyon
- CNRS
- LIRIS
| | | | | | | |
Collapse
|
46
|
Bartelme RP, Custer JM, Dupont CL, Espinoza JL, Torralba M, Khalili B, Carini P. Influence of Substrate Concentration on the Culturability of Heterotrophic Soil Microbes Isolated by High-Throughput Dilution-to-Extinction Cultivation. mSphere 2020; 5:e00024-20. [PMID: 31996418 PMCID: PMC6992367 DOI: 10.1128/msphere.00024-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 01/14/2020] [Indexed: 12/17/2022] Open
Abstract
The vast majority of microbes inhabiting oligotrophic shallow subsurface soil environments have not been isolated or studied under controlled laboratory conditions. In part, the challenges associated with isolating shallow subsurface microbes may persist because microbes in deeper soils are adapted to low nutrient availability or quality. Here, we use high-throughput dilution-to-extinction culturing to isolate shallow subsurface microbes from a conifer forest in Arizona, USA. We hypothesized that the concentration of heterotrophic substrates in microbiological growth medium would affect which microbial taxa were culturable from these soils. To test this, we diluted cells extracted from soil into one of two custom-designed defined growth media that differed by 100-fold in the concentration of amino acids and organic carbon. Across the two media, we isolated a total of 133 pure cultures, all of which were classified as Actinobacteria or Alphaproteobacteria The substrate availability dictated which actinobacterial phylotypes were culturable but had no significant effect on the culturability of Alphaproteobacteria We isolated cultures that were representative of the most abundant phylotype in the soil microbial community (Bradyrhizobium spp.) and representatives of five of the top 10 most abundant Actinobacteria phylotypes, including Nocardioides spp., Mycobacterium spp., and several other phylogenetically divergent lineages. Flow cytometry of nucleic acid-stained cells showed that cultures isolated on low-substrate medium had significantly lower nucleic acid fluorescence than those isolated on high-substrate medium. These results show that dilution-to-extinction is an effective method to isolate abundant soil microbes and that the concentration of substrates in culture medium influences the culturability of specific microbial lineages.IMPORTANCE Isolating environmental microbes and studying their physiology under controlled conditions are essential aspects of understanding their ecology. Subsurface ecosystems are typically nutrient-poor environments that harbor diverse microbial communities-the majority of which are thus far uncultured. In this study, we use modified high-throughput cultivation methods to isolate subsurface soil microbes. We show that a component of whether a microbe is culturable from subsurface soils is the concentration of growth substrates in the culture medium. Our results offer new insight into technical approaches and growth medium design that can be used to access the uncultured diversity of soil microbes.
Collapse
Affiliation(s)
- Ryan P Bartelme
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| | - Joy M Custer
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| | - Christopher L Dupont
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, California, USA
| | - Josh L Espinoza
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, California, USA
| | - Manolito Torralba
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, California, USA
| | - Banafshe Khalili
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
| | - Paul Carini
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| |
Collapse
|
47
|
Goodhead I, Blow F, Brownridge P, Hughes M, Kenny J, Krishna R, McLean L, Pongchaikul P, Beynon R, Darby AC. Large-scale and significant expression from pseudogenes in Sodalis glossinidius - a facultative bacterial endosymbiont. Microb Genom 2020; 6:e000285. [PMID: 31922467 PMCID: PMC7067036 DOI: 10.1099/mgen.0.000285] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 07/10/2019] [Indexed: 01/30/2023] Open
Abstract
The majority of bacterial genomes have high coding efficiencies, but there are some genomes of intracellular bacteria that have low gene density. The genome of the endosymbiont Sodalis glossinidius contains almost 50 % pseudogenes containing mutations that putatively silence them at the genomic level. We have applied multiple 'omic' strategies, combining Illumina and Pacific Biosciences Single-Molecule Real-Time DNA sequencing and annotation, stranded RNA sequencing and proteome analysis to better understand the transcriptional and translational landscape of Sodalis pseudogenes, and potential mechanisms for their control. Between 53 and 74 % of the Sodalis transcriptome remains active in cell-free culture. The mean sense transcription from coding domain sequences (CDSs) is four times greater than that from pseudogenes. Comparative genomic analysis of six Illumina-sequenced Sodalis isolates from different host Glossina species shows pseudogenes make up ~40 % of the 2729 genes in the core genome, suggesting that they are stable and/or that Sodalis is a recent introduction across the genus Glossina as a facultative symbiont. These data shed further light on the importance of transcriptional and translational control in deciphering host-microbe interactions. The combination of genomics, transcriptomics and proteomics gives a multidimensional perspective for studying prokaryotic genomes with a view to elucidating evolutionary adaptation to novel environmental niches.
Collapse
Affiliation(s)
- Ian Goodhead
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- School of Science, Engineering and Environment, Peel Building, University of Salford, M5 4WT, UK
| | - Frances Blow
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- Department of Entomology, Cornell University, Ithaca 14853, NY, USA
| | - Philip Brownridge
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - Margaret Hughes
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - John Kenny
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - Ritesh Krishna
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- IBM Research UK, STFC Daresbury Laboratory, Warrington, WA4 4AD, UK
| | - Lynn McLean
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - Pisut Pongchaikul
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - Rob Beynon
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| | - Alistair C. Darby
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
- Centre for Genomic Research, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK
| |
Collapse
|
48
|
Lawrence TJ, Amrine KCH, Swingley WD, Ardell DH. tRNA functional signatures classify plastids as late-branching cyanobacteria. BMC Evol Biol 2019; 19:224. [PMID: 31818253 PMCID: PMC6902448 DOI: 10.1186/s12862-019-1552-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 11/29/2019] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Eukaryotes acquired the trait of oxygenic photosynthesis through endosymbiosis of the cyanobacterial progenitor of plastid organelles. Despite recent advances in the phylogenomics of Cyanobacteria, the phylogenetic root of plastids remains controversial. Although a single origin of plastids by endosymbiosis is broadly supported, recent phylogenomic studies are contradictory on whether plastids branch early or late within Cyanobacteria. One underlying cause may be poor fit of evolutionary models to complex phylogenomic data. RESULTS Using Posterior Predictive Analysis, we show that recently applied evolutionary models poorly fit three phylogenomic datasets curated from cyanobacteria and plastid genomes because of heterogeneities in both substitution processes across sites and of compositions across lineages. To circumvent these sources of bias, we developed CYANO-MLP, a machine learning algorithm that consistently and accurately phylogenetically classifies ("phyloclassifies") cyanobacterial genomes to their clade of origin based on bioinformatically predicted function-informative features in tRNA gene complements. Classification of cyanobacterial genomes with CYANO-MLP is accurate and robust to deletion of clades, unbalanced sampling, and compositional heterogeneity in input tRNA data. CYANO-MLP consistently classifies plastid genomes into a late-branching cyanobacterial sub-clade containing single-cell, starch-producing, nitrogen-fixing ecotypes, consistent with metabolic and gene transfer data. CONCLUSIONS Phylogenomic data of cyanobacteria and plastids exhibit both site-process heterogeneities and compositional heterogeneities across lineages. These aspects of the data require careful modeling to avoid bias in phylogenomic estimation. Furthermore, we show that amino acid recoding strategies may be insufficient to mitigate bias from compositional heterogeneities. However, the combination of our novel tRNA-specific strategy with machine learning in CYANO-MLP appears robust to these sources of bias with high accuracy in phyloclassification of cyanobacterial genomes. CYANO-MLP consistently classifies plastids as late-branching Cyanobacteria, consistent with independent evidence from signature-based approaches and some previous phylogenetic studies.
Collapse
Affiliation(s)
- Travis J Lawrence
- Biosciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831 USA
- Quantitative and Systems Biology Program, University of California, Merced, 5200 North Lake Rd., Merced, CA, 95343 USA
| | - Katherine CH Amrine
- Quantitative and Systems Biology Program, University of California, Merced, 5200 North Lake Rd., Merced, CA, 95343 USA
- Insight Data Science, 500 3rd St., San Francisco, CA, 94107 USA
| | - Wesley D Swingley
- Department of Biological Sciences, Northern Illinois University, 1425 Lincoln Hwy., DeKalb, IL, 60115 USA
| | - David H Ardell
- Quantitative and Systems Biology Program, University of California, Merced, 5200 North Lake Rd., Merced, CA, 95343 USA
- Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, 5200 North Lake Rd., Merced, CA, 95343 USA
| |
Collapse
|
49
|
Tsementzi D, Castro Gordillo J, Mahagna M, Gottlieb Y, Konstantinidis KT. Comparison of closely related, uncultivated Coxiella tick endosymbiont population genomes reveals clues about the mechanisms of symbiosis. Environ Microbiol 2019; 20:1751-1764. [PMID: 29575448 DOI: 10.1111/1462-2920.14104] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 03/12/2018] [Accepted: 03/12/2018] [Indexed: 02/01/2023]
Abstract
Understanding the symbiotic interaction between Coxiella-like endosymbionts (CLE) and their tick hosts is challenging due to lack of isolates and difficulties in tick functional assays. Here we sequenced the metagenome of a CLE population from wild Rhipicephalus sanguineus ticks (CRs) and compared it to the previously published genome of its close relative, CLE of R. turanicus (CRt). The tick hosts are closely related sympatric species, and their two endosymbiont genomes are highly similar with only minor differences in gene content. Both genomes encode numerous pseudogenes, consistent with an ongoing genome reduction process. In silico flux balance metabolic analysis (FBA) revealed the excess production of L-proline for both genomes, indicating a possible proline transport from Coxiella to the tick. Additionally, both CR genomes encode multiple copies of the proline/betaine transporter, proP gene. Modelling additional Coxiellaceae members including other tick CLE, did not identify proline as an excreted metabolite. Although both CRs and CRt genomes encode intact B vitamin synthesis pathway genes, which are presumed to underlay the mechanism of CLE-tick symbiosis, the FBA analysis indicated no changes for their products. Therefore, this study provides new testable hypotheses for the symbiosis mechanism and a better understanding of CLE genome evolution and diversity.
Collapse
Affiliation(s)
- Despina Tsementzi
- Georgia Institute of Technology, School of Civil and Environmental Engineering, Atlanta, GA 30332, USA
| | - Juan Castro Gordillo
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Mustafa Mahagna
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Yuval Gottlieb
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Konstantinos T Konstantinidis
- Georgia Institute of Technology, School of Civil and Environmental Engineering, Atlanta, GA 30332, USA.,School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| |
Collapse
|
50
|
Transcriptional noise and exaptation as sources for bacterial sRNAs. Biochem Soc Trans 2019; 47:527-539. [PMID: 30837318 DOI: 10.1042/bst20180171] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 02/01/2019] [Accepted: 02/01/2019] [Indexed: 11/17/2022]
Abstract
Understanding how new genes originate and integrate into cellular networks is key to understanding evolution. Bacteria present unique opportunities for both the natural history and experimental study of gene origins, due to their large effective population sizes, rapid generation times, and ease of genetic manipulation. Bacterial small non-coding RNAs (sRNAs), in particular, many of which operate through a simple antisense regulatory logic, may serve as tractable models for exploring processes of gene origin and adaptation. Understanding how and on what timescales these regulatory molecules arise has important implications for understanding the evolution of bacterial regulatory networks, in particular, for the design of comparative studies of sRNA function. Here, we introduce relevant concepts from evolutionary biology and review recent work that has begun to shed light on the timescales and processes through which non-functional transcriptional noise is co-opted to provide regulatory functions. We explore possible scenarios for sRNA origin, focusing on the co-option, or exaptation, of existing genomic structures which may provide protected spaces for sRNA evolution.
Collapse
|