1
|
Friend virus severity is associated with male mouse social status and environmental temperature. Anim Behav 2022; 187:221-231. [PMID: 35602411 PMCID: PMC9119425 DOI: 10.1016/j.anbehav.2022.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Pathogen virulence is highly variable within populations, and although many factors contributing to virulence differences are known, there is still much variation left unexplained. Identifying and characterizing environmental conditions associated with different virulence levels is therefore an important undertaking in infectious disease research. One factor considered to be a major determinant of overall health and susceptibility to disease in social animals is social status. Health differences associated with social status are thought to be caused by different levels of chronic stress in higher- versus lower-status individuals. There is considerable evidence that these effects extend to the standing immune profile and that social status directly influences susceptibility to pathogens. Here we examined the association between dominance status in male wild-derived house mice, Mus musculus, and susceptibility to Friend virus complex in the context of seminatural populations with intense male-male competition and no predation. Due to an interruption in our facility's heating system, we were unexpectedly presented with the opportunity to assess how reduced ambient temperature influences the association of host social status and pathogen virulence. Environmental temperature has been implicated as a contributor to pathogen virulence, giving us a unique chance to examine its role in a previously unexamined pathogen system, while the added context of social status can expand our understanding of how the interaction of different environmental conditions affects virulence. We found that pathogen virulence and replication were lower in socially dominant hosts compared to nondominant hosts. When temperature was reduced, cool enclosure-housed dominant males were more susceptible to infection than their warm enclosure-housed counterparts. The mechanistic underpinnings that link infectious disease and social status remain difficult to disentangle from their associated factors, but this study opens the door for future experiments using a novel approach in the most well-studied mammalian model available.
Collapse
|
2
|
Hoang KL, King KC. Symbiont-mediated immune priming in animals through an evolutionary lens. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35442184 DOI: 10.1099/mic.0.001181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Protective symbionts can defend hosts from parasites through several mechanisms, from direct interference to modulating host immunity, with subsequent effects on host and parasite fitness. While research on symbiont-mediated immune priming (SMIP) has focused on ecological impacts and agriculturally important organisms, the evolutionary implications of SMIP are less clear. Here, we review recent advances made in elucidating the ecological and molecular mechanisms by which SMIP occurs. We draw on current works to discuss the potential for this phenomenon to drive host, parasite, and symbiont evolution. We also suggest approaches that can be used to address questions regarding the impact of immune priming on host-microbe dynamics and population structures. Finally, due to the transient nature of some symbionts involved in SMIP, we discuss what it means to be a protective symbiont from ecological and evolutionary perspectives and how such interactions can affect long-term persistence of the symbiosis.
Collapse
Affiliation(s)
- Kim L Hoang
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| | - Kayla C King
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| |
Collapse
|
3
|
Drew GC, Stevens EJ, King KC. Microbial evolution and transitions along the parasite-mutualist continuum. Nat Rev Microbiol 2021; 19:623-638. [PMID: 33875863 PMCID: PMC8054256 DOI: 10.1038/s41579-021-00550-7] [Citation(s) in RCA: 100] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2021] [Indexed: 12/28/2022]
Abstract
Virtually all plants and animals, including humans, are home to symbiotic microorganisms. Symbiotic interactions can be neutral, harmful or have beneficial effects on the host organism. However, growing evidence suggests that microbial symbionts can evolve rapidly, resulting in drastic transitions along the parasite-mutualist continuum. In this Review, we integrate theoretical and empirical findings to discuss the mechanisms underpinning these evolutionary shifts, as well as the ecological drivers and why some host-microorganism interactions may be stuck at the end of the continuum. In addition to having biomedical consequences, understanding the dynamic life of microorganisms reveals how symbioses can shape an organism's biology and the entire community, particularly in a changing world.
Collapse
Affiliation(s)
| | | | - Kayla C King
- Department of Zoology, University of Oxford, Oxford, UK.
| |
Collapse
|
4
|
Cornwall DH, Ruff JS, Zachary ER, Young CP, Maguire KM, Painter RJ, Trujillo SM, Potts WK. Horizontal transmission of a murine retrovirus is driven by males within semi‐natural enclosures. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13766] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Douglas H. Cornwall
- School of Biological Sciences University of Utah Salt Lake City UT USA
- Department of Pathology University of Utah Salt Lake City UT USA
| | - James S. Ruff
- School of Biological Sciences University of Utah Salt Lake City UT USA
| | | | - Chloe P. Young
- School of Biological Sciences University of Utah Salt Lake City UT USA
| | | | - Rachel J. Painter
- School of Biological Sciences University of Utah Salt Lake City UT USA
| | | | - Wayne K. Potts
- School of Biological Sciences University of Utah Salt Lake City UT USA
| |
Collapse
|
5
|
Elrashdy F, Redwan EM, Uversky VN. Why COVID-19 Transmission Is More Efficient and Aggressive Than Viral Transmission in Previous Coronavirus Epidemics? Biomolecules 2020; 10:E1312. [PMID: 32933047 PMCID: PMC7565143 DOI: 10.3390/biom10091312] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/08/2020] [Indexed: 12/19/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing a pandemic of coronavirus disease 2019 (COVID-19). The worldwide transmission of COVID-19 from human to human is spreading like wildfire, affecting almost every country in the world. In the past 100 years, the globe did not face a microbial pandemic similar in scale to COVID-19. Taken together, both previous outbreaks of other members of the coronavirus family (severe acute respiratory syndrome (SARS-CoV) and middle east respiratory syndrome (MERS-CoV)) did not produce even 1% of the global harm already inflicted by COVID-19. There are also four other CoVs capable of infecting humans (HCoVs), which circulate continuously in the human population, but their phenotypes are generally mild, and these HCoVs received relatively little attention. These dramatic differences between infection with HCoVs, SARS-CoV, MERS-CoV, and SARS-CoV-2 raise many questions, such as: Why is COVID-19 transmitted so quickly? Is it due to some specific features of the viral structure? Are there some specific human (host) factors? Are there some environmental factors? The aim of this review is to collect and concisely summarize the possible and logical answers to these questions.
Collapse
Affiliation(s)
- Fatma Elrashdy
- Department of Endemic Medicine and Hepatogastroenterology, Kasr Alainy School of Medicine, Cairo University, Cairo 11562, Egypt;
| | - Elrashdy M. Redwan
- Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
| | - Vladimir N. Uversky
- Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
- Department of Molecular Medicine and USF Health Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Pushchino, 142290 Moscow, Russia
| |
Collapse
|
6
|
White PS, Choi A, Pandey R, Menezes A, Penley M, Gibson AK, de Roode J, Morran L. Host heterogeneity mitigates virulence evolution. Biol Lett 2020; 16:20190744. [PMID: 31992149 PMCID: PMC7013476 DOI: 10.1098/rsbl.2019.0744] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 12/19/2019] [Indexed: 01/21/2023] Open
Abstract
Parasites often infect genetically diverse host populations, and the evolutionary trajectories of parasite populations may be shaped by levels of host heterogeneity. Mixed genotype host populations, compared to homogeneous host populations, can reduce parasite prevalence and potentially reduce rates of parasite adaptation due to trade-offs associated with adapting to specific host genotypes. Here, we used experimental evolution to select for increased virulence in populations of the bacterial parasite Serratia marcescens exposed to either heterogeneous or homogeneous populations of Caenorhabditis elegans. We found that parasites exposed to heterogeneous host populations evolved significantly less virulence than parasites exposed to homogeneous host populations over several hundred bacterial generations. Thus, host heterogeneity impeded parasite adaptation to host populations. While we detected trade-offs in virulence evolution, parasite adaptation to two specific host genotypes also resulted in modestly increased virulence against the reciprocal host genotypes. These results suggest that parasite adaptation to heterogeneous host populations may be impeded by both trade-offs and a reduction in the efficacy of selection as different host genotypes exert different selective pressures on a parasite population.
Collapse
Affiliation(s)
- P. Signe White
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
- Population Biology, Ecology, and Evolution Graduate Program, Laney Graduate School, Emory University, Atlanta, GA 30322, USA
| | - Angela Choi
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - Rishika Pandey
- Department of Genetics, Franklin College of Arts and Sciences, University of Georgia, Athens, GA 30602, USA
| | - Arthur Menezes
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - McKenna Penley
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - Amanda K. Gibson
- Department of Biology, College and Graduate School of Arts and Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | - Jacobus de Roode
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - Levi Morran
- Department of Biology, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| |
Collapse
|
7
|
Abstract
Mathematical epidemiology is a well-recognized discipline to model infectious diseases. It also provides guidance for public health officials to limit outbreaks. Nevertheless, epidemics take societies by surprise every now and then, for example, when the Ebola virus epidemic raged seemingly unrestrained in Western Africa. We provide insight to this capricious character of nature by describing the epidemic as a natural process, i.e., a phenomenon governed by thermodynamics. Our account, based on statistical mechanics of open systems, clarifies that it is impossible to predict accurately epidemic courses because everything depends on everything else. Nonetheless, the thermodynamic theory yields a comprehensive and analytical view of the epidemic. The tenet subsumes various processes in a scale-free manner from the molecular to the societal levels. The holistic view accentuates overarching procedures in arresting and eradicating epidemics.
Collapse
Affiliation(s)
- Mikko Koivu-Jolma
- Department of Physics, University of Helsinki, Helsinki, FI-00014, Finland
| | - Arto Annila
- Department of Physics, University of Helsinki, Helsinki, FI-00014, Finland; Department of Biosciences, University of Helsinki, Helsinki, FI-00014, Finland.
| |
Collapse
|
8
|
Cornwall DH, Kubinak JL, Zachary E, Stark DL, Seipel D, Potts WK. Experimental manipulation of population-level MHC diversity controls pathogen virulence evolution in Mus musculus. J Evol Biol 2018; 31:314-322. [PMID: 29266576 DOI: 10.1111/jeb.13225] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 11/30/2017] [Accepted: 12/13/2017] [Indexed: 12/14/2022]
Abstract
The virulence levels attained by serial passage of pathogens through similar host genotypes are much higher than observed in natural systems; however, it is unknown what keeps natural virulence levels below these empirically demonstrated maximum levels. One hypothesis suggests that host diversity impedes pathogen virulence, because adaptation to one host genotype carries trade-offs in the ability to replicate and cause disease in other host genotypes. To test this hypothesis, with the simplest level of population diversity within the loci of the major histocompatibility complex (MHC), we serially passaged Friend virus complex (FVC) through two rounds, in hosts with either the same MHC genotypes (pure passage) or hosts with different MHC genotypes (alternated passage). Alternated passages showed a significant overall reduction in viral titre (31%) and virulence (54%) when compared to pure passages. Furthermore, a resistant host genotype initially dominated any effects due to MHC diversity; however, when FVC was allowed to adapt to the resistant host genotype, predicted MHC effects emerged; that is, alternated lines show reduced virulence. These data indicate serial exposure to diverse MHC genotypes is an impediment to pathogen adaptation, suggesting genetic variation at MHC loci is important for limiting virulence in a rapidly evolving pathogen and supports negative frequency-dependent selection as a force maintaining MHC diversity in host populations.
Collapse
Affiliation(s)
- D H Cornwall
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - J L Kubinak
- University of South Carolina School of Medicine, Columbia, SC, USA
| | - E Zachary
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - D L Stark
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - D Seipel
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - W K Potts
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
9
|
Bono LM, Smith LB, Pfennig DW, Burch CL. The emergence of performance trade‐offs during local adaptation: insights from experimental evolution. Mol Ecol 2017; 26:1720-1733. [DOI: 10.1111/mec.13979] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/15/2016] [Accepted: 12/19/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Lisa M. Bono
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - Leno B. Smith
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - David W. Pfennig
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| | - Christina L. Burch
- Department of Biology University of North Carolina at Chapel Hill CB# 3280 Chapel Hill NC 27599 USA
| |
Collapse
|
10
|
Hoang KL, Morran LT, Gerardo NM. Experimental Evolution as an Underutilized Tool for Studying Beneficial Animal-Microbe Interactions. Front Microbiol 2016; 7:1444. [PMID: 27679620 PMCID: PMC5020044 DOI: 10.3389/fmicb.2016.01444] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 08/30/2016] [Indexed: 11/29/2022] Open
Abstract
Microorganisms play a significant role in the evolution and functioning of the eukaryotes with which they interact. Much of our understanding of beneficial host–microbe interactions stems from studying already established associations; we often infer the genotypic and environmental conditions that led to the existing host–microbe relationships. However, several outstanding questions remain, including understanding how host and microbial (internal) traits, and ecological and evolutionary (external) processes, influence the origin of beneficial host–microbe associations. Experimental evolution has helped address a range of evolutionary and ecological questions across different model systems; however, it has been greatly underutilized as a tool to study beneficial host–microbe associations. In this review, we suggest ways in which experimental evolution can further our understanding of the proximate and ultimate mechanisms shaping mutualistic interactions between eukaryotic hosts and microbes. By tracking beneficial interactions under defined conditions or evolving novel associations among hosts and microbes with little prior evolutionary interaction, we can link specific genotypes to phenotypes that can be directly measured. Moreover, this approach will help address existing puzzles in beneficial symbiosis research: how symbioses evolve, how symbioses are maintained, and how both host and microbe influence their partner’s evolutionary trajectories. By bridging theoretical predictions and empirical tests, experimental evolution provides us with another approach to test hypotheses regarding the evolution of beneficial host–microbe associations.
Collapse
Affiliation(s)
- Kim L Hoang
- Department of Biology, O. Wayne Rollins Research Center, Emory University Atlanta, GA, USA
| | - Levi T Morran
- Department of Biology, O. Wayne Rollins Research Center, Emory University Atlanta, GA, USA
| | - Nicole M Gerardo
- Department of Biology, O. Wayne Rollins Research Center, Emory University Atlanta, GA, USA
| |
Collapse
|
11
|
Kubinak JL, Cornwall DH, Hasenkrug KJ, Adler FR, Potts WK. Serial infection of diverse host (Mus) genotypes rapidly impedes pathogen fitness and virulence. Proc Biol Sci 2015; 282:20141568. [PMID: 25392466 DOI: 10.1098/rspb.2014.1568] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Reduced genetic variation among hosts may favour the emergence of virulent infectious diseases by enhancing pathogen replication and its associated virulence due to adaptation to a limited set of host genotypes. Here, we test this hypothesis using experimental evolution of a mouse-specific retroviral pathogen, Friend virus (FV) complex. We demonstrate rapid fitness (i.e. viral titre) and virulence increases when FV complex serially infects a series of inbred mice representing the same genotype, but not when infecting a diverse array of inbred mouse strains modelling the diversity in natural host populations. Additionally, a single infection of a different host genotype was sufficient to constrain the emergence of a high fitness/high virulence FV complex phenotype in these experiments. The potent inhibition of viral fitness and virulence was associated with an observed loss of the defective retroviral genome (spleen focus-forming virus), whose presence exacerbates infection and drives disease in susceptible mice. Results from our experiments provide an important first step in understanding how genetic variation among vertebrate hosts influences pathogen evolution and suggests that serial exposure to different genotypes within a single host species may act as a constraint on pathogen adaptation that prohibits the emergence of more virulent infections. From a practical perspective, these results have implications for low-diversity host populations such as endangered species and domestic animals.
Collapse
Affiliation(s)
- Jason L Kubinak
- Department of Pathology, Division of Microbiology and Immunology, School of Medicine, University of Utah, 15 North Medical Drive East, Salt Lake City, UT 84112, USA
| | - Douglas H Cornwall
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA
| | - Kim J Hasenkrug
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South 4th St., Hamilton, MT 59840, USA
| | - Frederick R Adler
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA Department of Mathematics, University of Utah, 155 South 1400 East, Salt Lake City, UT 84112, USA
| | - Wayne K Potts
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112, USA
| |
Collapse
|
12
|
Aalto SL, Decaestecker E, Pulkkinen K. A three-way perspective of stoichiometric changes on host-parasite interactions. Trends Parasitol 2015; 31:333-40. [PMID: 25978937 DOI: 10.1016/j.pt.2015.04.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/09/2015] [Accepted: 04/09/2015] [Indexed: 01/18/2023]
Abstract
Changes in environmental nutrients play a crucial role in driving disease dynamics, but global patterns in nutrient-driven changes in disease are difficult to predict. In this paper we use ecological stoichiometry as a framework to review host-parasite interactions under changing nutrient ratios, focusing on three pathways: (i) altered host resistance and parasite virulence through host stoichiometry (ii) changed encounter or contact rates at population level, and (iii) changed host community structure. We predict that the outcome of nutrient changes on host-parasite interactions depends on which pathways are modified, and suggest that the outcome of infection could depend on the overlap in stoichiometric requirements of the host and the parasite. We hypothesize that environmental nutrient enrichment alters infectivity dynamics leading to fluctuating selection dynamics in host-parasite coevolution.
Collapse
Affiliation(s)
- Sanni L Aalto
- Department of Biological and Environmental Science, University of Jyväskylä, PO Box 35, 40014 Jyväskylä, Finland.
| | - Ellen Decaestecker
- Laboratory of Aquatic Biology, Department of Biology, Katholieke Universiteit Leuven Kulak, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium
| | - Katja Pulkkinen
- Department of Biological and Environmental Science, University of Jyväskylä, PO Box 35, 40014 Jyväskylä, Finland
| |
Collapse
|
13
|
Affiliation(s)
- James J. Bull
- The Institute for Cellular and Molecular Biology, The University of Texas, Austin, Texas, United States of America
- Center for Computational Biology and Bioinformatics, The University of Texas at Austin, Austin, Texas, United States of America
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Adam S. Lauring
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
| |
Collapse
|
14
|
Barclay VC, Kennedy DA, Weaver VC, Sim D, Lloyd-Smith JO, Read AF. The Effect of Immunodeficiency on the Evolution of Virulence: An Experimental Test with the Rodent MalariaPlasmodium chabaudi. Am Nat 2014; 184 Suppl 1:S47-57. [DOI: 10.1086/676887] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
15
|
Van Tyne D, Gilmore MS. Friend turned foe: evolution of enterococcal virulence and antibiotic resistance. Annu Rev Microbiol 2014; 68:337-56. [PMID: 25002090 DOI: 10.1146/annurev-micro-091213-113003] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The enterococci are an ancient genus that evolved along with the tree of life. These intrinsically rugged bacteria are highly adapted members of the intestinal consortia of a range of hosts that spans the animal kingdom. Enterococci are also leading opportunistic hospital pathogens, causing infections that are often resistant to treatment with most antibiotics. Despite the importance of enterococci as hospital pathogens, the vast majority live outside of humans, and nearly all of their evolutionary history took place before the appearance of modern humans. Because hospital infections represent evolutionary end points, traits that exacerbate human infection are unlikely to have evolved for that purpose. However, clusters of traits have converged in specific lineages that are well adapted to colonize the antibiotic-perturbed gastrointestinal tracts of patients and that thrive in the hospital environment. Here we discuss these traits in an evolutionary context, as well as how comparative genomics is providing new insights into the evolution of the enterococci.
Collapse
Affiliation(s)
- Daria Van Tyne
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114
| | | |
Collapse
|
16
|
Barclay VC. Variation in host resistance could limit the spread of more broadly virulent pathogens. Virulence 2013; 4:347-9. [PMID: 23689611 PMCID: PMC3714125 DOI: 10.4161/viru.25061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|