1
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Olarte-Castillo XA, Plimpton L, McQueary H, Sun Y, Yu YT, Cover S, Richardson AN, Jin Y, Grenier JK, Cummings KJ, Bunting E, Diuk-Wasser M, Needle D, Schuler K, Stanhope MJ, Whittaker G, Goodman LB. Detection and characterization of novel luchacoviruses, genus Alphacoronavirus, in saliva and feces of meso-carnivores in the northeastern United States. J Virol 2023; 97:e0082923. [PMID: 37882520 PMCID: PMC10688340 DOI: 10.1128/jvi.00829-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 10/08/2023] [Indexed: 10/27/2023] Open
Abstract
IMPORTANCE Several coronaviruses (CoVs) have been detected in domesticated, farmed, and wild meso-carnivores, causing a wide range of diseases and infecting diverse species, highlighting their important but understudied role in the epidemiology of these viruses. Assessing the viral diversity hosted in wildlife species is essential to understand their significance in the cross-species transmission of CoVs. Our focus here was on CoV discovery in meso-carnivores in the Northeast United States as a potential "hotspot" area with high density of humans and urban wildlife. This study identifies novel alphacoronaviruses circulating in multiple free-ranging wild and domestic species in this area and explores their potential epidemiological importance based on regions of the Spike gene, which are relevant for virus-host interactions.
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Affiliation(s)
- Ximena A. Olarte-Castillo
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
| | - Laura Plimpton
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, USA
| | - Holly McQueary
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Yining Sun
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Y. Tina Yu
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Sarah Cover
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Amy N. Richardson
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Yuhan Jin
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Jennifer K. Grenier
- Transcriptional Regulation and Expression Facility, Biotechnology Resource Center, Institute of Biotechnology, Cornell University, Ithaca, New York, USA
| | - Kevin J. Cummings
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Elizabeth Bunting
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Maria Diuk-Wasser
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, USA
| | - David Needle
- New Hampshire Veterinary Diagnostic Laboratory, College of Life Sciences and Agriculture, University of New Hampshire, Durham, USA
| | - Krysten Schuler
- Cornell Wildlife Health Lab, Animal Health Diagnostic Center, Cornell College of Veterinary Medicine, Ithaca, New York, USA
| | - Michael J. Stanhope
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Gary Whittaker
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Laura B. Goodman
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
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2
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Olarte-Castillo XA, Plimpton L, McQueary H, Sun Y, Yu YT, Cover S, Richardson AN, Jin Y, Grenier JK, Cummings KJ, Bunting E, Diuk-Wasser M, Needle D, Schuler K, Stanhope MJ, Whittaker G, Goodman LB. Detection and characterization of novel luchacoviruses, genus Alphacoronavirus, shed in saliva and feces of meso-carnivores in the northeastern United States. bioRxiv 2023:2023.05.31.541188. [PMID: 37745528 PMCID: PMC10515766 DOI: 10.1101/2023.05.31.541188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Small to mid-sized carnivores, or meso-carnivores, comprise a group of diverse mammals, many of which can adapt to anthropogenically disturbed environments. Wild meso-carnivores living in urban areas may get exposed to or spread pathogens to other species, including stray/feral domestic animals. Several coronaviruses (CoVs) have been detected in domesticated and farmed meso-carnivores, but knowledge of CoVs circulating in free-ranging wild meso-carnivores remains limited. In this study, we analyzed 321 samples collected between 2016 and 2022 from 9 species of free-ranging wild meso-carnivores and stray/feral domestic cats in the northeastern United States. Using a pan-CoV PCR, we screened tissues, feces, and saliva, nasal, and rectal swabs. We detected CoV RNA in fecal and saliva samples of animals in four species: fisher (Pekania pennanti), bobcat (Lynx rufus), red fox (Vulpes vulpes), and domestic cat (Felis catus). Next-generation sequencing revealed that all these viruses belonged to the Luchacovirus subgenus (Alphacoronavirus genus), previously reported only in rodents and lagomorphs (i.e., rabbits). Genetic comparison of the 3'-end of the genome (~12,000bp) revealed that although the viruses detected group with, and have a genetic organization similar to other luchacoviruses, they are genetically distinct from those from rodents and lagomorphs. Genetic characterization of the spike protein revealed that the meso-carnivore luchacoviruses do not have an S1/S2 cleavage motif but do have highly variable structural loops containing cleavage motifs similar to those identified in certain pathogenic CoVs. This study highlights the importance of characterizing the spike protein of CoVs in wild species for further targeted epidemiologic monitoring.
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Affiliation(s)
- Ximena A. Olarte-Castillo
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
| | - Laura Plimpton
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, USA
| | - Holly McQueary
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Yining Sun
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Y. Tina Yu
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Sarah Cover
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Amy N. Richardson
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Yuhan Jin
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Jennifer K. Grenier
- Transcriptional Regulation and Expression Facility, Biotechnology Resource Center, Institute of Biotechnology, Cornell University
| | - Kevin J. Cummings
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Elizabeth Bunting
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Maria Diuk-Wasser
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, USA
| | - David Needle
- New Hampshire Veterinary Diagnostic Laboratory, College of Life Sciences and Agriculture, University of New Hampshire
| | - Krysten Schuler
- Cornell Wildlife Health Lab, Animal Health Diagnostic Center, Cornell College of Veterinary Medicine, 240 Farrier Road, Ithaca, NY 14853
| | - Michael J. Stanhope
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Gary Whittaker
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Laura B. Goodman
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
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3
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Zehr JD, Kosakovsky Pond SL, Millet JK, Olarte-Castillo XA, Lucaci AG, Shank SD, Ceres KM, Choi A, Whittaker GR, Goodman LB, Stanhope MJ. Natural selection differences detected in key protein domains between non-pathogenic and pathogenic Feline Coronavirus phenotypes. Virus Evol 2023; 9:vead019. [PMID: 37038392 PMCID: PMC10082545 DOI: 10.1093/ve/vead019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/14/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023] Open
Abstract
Abstract
Feline Coronaviruses (FCoVs) commonly cause mild enteric infections in felines worldwide (termed Feline Enteric Coronavirus [FECV]), with around 12% developing into deadly Feline Infectious Peritonitis (FIP; Feline Infectious Peritonitis Virus [FIPV]). Genomic differences between FECV and FIPV have been reported, yet the putative genotypic basis of the highly pathogenic phenotype remains unclear. Here, we used state-of-the-art molecular evolutionary genetic statistical techniques to identify and compare differences in natural selection pressure between FECV and FIPV sequences, as well as to identify FIPV and FECV specific signals of positive selection. We analyzed full length FCoV protein coding genes thought to contain mutations associated with FIPV (Spike, ORF3abc, and ORF7ab). We identified two sites exhibiting differences in natural selection pressure between FECV and FIPV: one within the S1/S2 furin cleavage site, and the other within the fusion domain of Spike. We also found 15 sites subject to positive selection associated with FIPV within Spike, 11 of which have not previously been suggested as possibly relevant to FIP development. These sites fall within Spike protein subdomains that participate in host cell receptor interaction, immune evasion, tropism shifts, host cellular entry, and viral escape. There were 14 sites (12 novel) within Spike under positive selection associated with the FECV phenotype, almost exclusively within the S1/S2 furin cleavage site and adjacent C domain, along with a signal of relaxed selection in FIPV relative to FECV, suggesting that furin cleavage functionality may not be needed for FIPV. Positive selection inferred in ORF7b was associated with the FECV phenotype, and included 24 positively selected sites, while ORF7b had signals of relaxed selection in FIPV. We found evidence of positive selection in ORF3c in FCoV wide analyses, but no specific association with the FIPV or FECV phenotype. We hypothesize that some combination of mutations in FECV may contribute to FIP development, and that is unlikely to be one singular “switch” mutational event. This work expands our understanding of the complexities of FIP development and provides insights into how evolutionary forces may alter pathogenesis in coronavirus genomes.
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Affiliation(s)
| | | | | | | | | | | | | | - Annette Choi
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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4
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Zehr JD, Pond SLK, Millet JK, Olarte-Castillo XA, Lucaci AG, Shank SD, Ceres KM, Choi A, Whittaker GR, Goodman LB, Stanhope MJ. Natural selection differences detected in key protein domains between non-pathogenic and pathogenic Feline Coronavirus phenotypes. bioRxiv 2023:2023.01.11.523607. [PMID: 36712007 PMCID: PMC9882035 DOI: 10.1101/2023.01.11.523607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Feline Coronaviruses (FCoVs) commonly cause mild enteric infections in felines worldwide (termed Feline Enteric Coronavirus [FECV]), with around 12% developing into deadly Feline Infectious Peritonitis (FIP; Feline Infectious Peritonitis Virus [FIPV]). Genomic differences between FECV and FIPV have been reported, yet the putative genotypic basis of the highly pathogenic phenotype remains unclear. Here, we used state-of-the-art molecular evolutionary genetic statistical techniques to identify and compare differences in natural selection pressure between FECV and FIPV sequences, as well as to identify FIPV and FECV specific signals of positive selection. We analyzed full length FCoV protein coding genes thought to contain mutations associated with FIPV (Spike, ORF3abc, and ORF7ab). We identified two sites exhibiting differences in natural selection pressure between FECV and FIPV: one within the S1/S2 furin cleavage site, and the other within the fusion domain of Spike. We also found 15 sites subject to positive selection associated with FIPV within Spike, 11 of which have not previously been suggested as possibly relevant to FIP development. These sites fall within Spike protein subdomains that participate in host cell receptor interaction, immune evasion, tropism shifts, host cellular entry, and viral escape. There were 14 sites (12 novel) within Spike under positive selection associated with the FECV phenotype, almost exclusively within the S1/S2 furin cleavage site and adjacent C domain, along with a signal of relaxed selection in FIPV relative to FECV, suggesting that furin cleavage functionality may not be needed for FIPV. Positive selection inferred in ORF7b was associated with the FECV phenotype, and included 24 positively selected sites, while ORF7b had signals of relaxed selection in FIPV. We found evidence of positive selection in ORF3c in FCoV wide analyses, but no specific association with the FIPV or FECV phenotype. We hypothesize that some combination of mutations in FECV may contribute to FIP development, and that is unlikely to be one singular "switch" mutational event. This work expands our understanding of the complexities of FIP development and provides insights into how evolutionary forces may alter pathogenesis in coronavirus genomes.
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Affiliation(s)
- Jordan D. Zehr
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Sergei L. Kosakovsky Pond
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Jean K. Millet
- Université Paris-Saclay, INRAE, UVSQ, Virologie et Immunologie Moléculaires, 78352 Jouyen-Josas, France
| | - Ximena A. Olarte-Castillo
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA,James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
| | - Alexander G. Lucaci
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Stephen D. Shank
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Kristina M. Ceres
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Annette Choi
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.,Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Gary R. Whittaker
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.,Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Laura B. Goodman
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.,James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
| | - Michael J. Stanhope
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.,Corresponding author ()
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5
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Abstract
The increased accessibility of next generation sequencing has allowed enough genomes from a given bacterial species to be sequenced to describe the distribution of genes in the pangenome, without limiting analyses to genes present in reference strains. Although some taxa have thousands of whole genome sequences available on public databases, most genomes were sequenced with short read technology, resulting in incomplete assemblies. Studying pangenomes could lead to important insights into adaptation, pathogenicity, or molecular epidemiology, however given the known information loss inherent in analyzing contig-level assemblies, these inferences may be biased or inaccurate. In this study we describe the pangenome of a clonally evolving pathogen,
Mycobacterium bovis
, and examine the utility of gene content variation in
M. bovis
outbreak investigation. We constructed the
M. bovis
pangenome using 1463 de novo assembled genomes. We tested the assumption of strict clonal evolution by studying evidence of recombination in core genes and analyzing the distribution of accessory genes among core monophyletic groups. To determine if gene content variation could be utilized in outbreak investigation, we carefully examined accessory genes detected in a well described
M. bovis
outbreak in Minnesota. We found significant errors in accessory gene classification. After accounting for these errors, we show that
M. bovis
has a much smaller accessory genome than previously described and provide evidence supporting ongoing clonal evolution and a closed pangenome, with little gene content variation generated over outbreaks. We also identified frameshift mutations in multiple genes, including a mutation in glpK, which has recently been associated with antibiotic tolerance in
Mycobacterium tuberculosis
. A pangenomic approach enables a more comprehensive analysis of genome dynamics than is possible with reference-based approaches; however, without critical evaluation of accessory gene content, inferences of transmission patterns employing these loci could be misguided.
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Affiliation(s)
- Kristina M Ceres
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Yrjö T Gröhn
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.,Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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6
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Zehr JD, Pond SLK, Martin DP, Ceres K, Whittaker GR, Millet JK, Goodman LB, Stanhope MJ. Recent Zoonotic Spillover and Tropism Shift of a Canine Coronavirus Is Associated with Relaxed Selection and Putative Loss of Function in NTD Subdomain of Spike Protein. Viruses 2022; 14:v14050853. [PMID: 35632597 PMCID: PMC9145938 DOI: 10.3390/v14050853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/07/2022] [Accepted: 04/19/2022] [Indexed: 02/04/2023] Open
Abstract
A canine coronavirus (CCoV) has now been reported from two independent human samples from Malaysia (respiratory, collected in 2017–2018; CCoV-HuPn-2018) and Haiti (urine, collected in 2017); these two viruses were nearly genetically identical. In an effort to identify any novel adaptations associated with this apparent shift in tropism we carried out detailed evolutionary analyses of the spike gene of this virus in the context of related Alphacoronavirus 1 species. The spike 0-domain retains homology to CCoV2b (enteric infections) and Transmissible Gastroenteritis Virus (TGEV; enteric and respiratory). This domain is subject to relaxed selection pressure and an increased rate of molecular evolution. It contains unique amino acid substitutions, including within a region important for sialic acid binding and pathogenesis in TGEV. Overall, the spike gene is extensively recombinant, with a feline coronavirus type II strain serving a prominent role in the recombinant history of the virus. Molecular divergence time for a segment of the gene where temporal signal could be determined, was estimated at around 60 years ago. We hypothesize that the virus had an enteric origin, but that it may be losing that particular tropism, possibly because of mutations in the sialic acid binding region of the spike 0-domain.
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Affiliation(s)
- Jordan D. Zehr
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, PA 19122, USA; (J.D.Z.); (S.L.K.P.)
| | - Sergei L. Kosakovsky Pond
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, PA 19122, USA; (J.D.Z.); (S.L.K.P.)
| | - Darren P. Martin
- Computational Biology Division, Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory, Cape Town 7549, South Africa;
| | - Kristina Ceres
- Department of Public and Ecosystem Health, Cornell University, Ithaca, NY 14853, USA; (K.C.); (G.R.W.); (L.B.G.)
| | - Gary R. Whittaker
- Department of Public and Ecosystem Health, Cornell University, Ithaca, NY 14853, USA; (K.C.); (G.R.W.); (L.B.G.)
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Jean K. Millet
- Unité de Virologie et Immunologie Moléculaires, UVSQ, INRAE, Université Paris-Saclay, 78350 Jouy-en-Josas, France;
| | - Laura B. Goodman
- Department of Public and Ecosystem Health, Cornell University, Ithaca, NY 14853, USA; (K.C.); (G.R.W.); (L.B.G.)
- Baker Institute for Animal Health, Cornell University, Ithaca, NY 14850, USA
| | - Michael J. Stanhope
- Department of Public and Ecosystem Health, Cornell University, Ithaca, NY 14853, USA; (K.C.); (G.R.W.); (L.B.G.)
- Correspondence:
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7
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de Klerk A, Swanepoel P, Lourens R, Zondo M, Abodunran I, Lytras S, MacLean OA, Robertson D, Kosakovsky Pond SL, Zehr JD, Kumar V, Stanhope MJ, Harkins G, Murrell B, Martin DP. Conserved recombination patterns across coronavirus subgenera. Virus Evol 2022; 8:veac054. [PMID: 35814334 PMCID: PMC9261289 DOI: 10.1093/ve/veac054] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 03/03/2022] [Accepted: 06/10/2022] [Indexed: 11/12/2022] Open
Abstract
Recombination contributes to the genetic diversity found in coronaviruses and is known to be a prominent mechanism whereby they evolve. It is apparent, both from controlled experiments and in genome sequences sampled from nature, that patterns of recombination in coronaviruses are non-random and that this is likely attributable to a combination of sequence features that favour the occurrence of recombination break points at specific genomic sites, and selection disfavouring the survival of recombinants within which favourable intra-genome interactions have been disrupted. Here we leverage available whole-genome sequence data for six coronavirus subgenera to identify specific patterns of recombination that are conserved between multiple subgenera and then identify the likely factors that underlie these conserved patterns. Specifically, we confirm the non-randomness of recombination break points across all six tested coronavirus subgenera, locate conserved recombination hot- and cold-spots, and determine that the locations of transcriptional regulatory sequences are likely major determinants of conserved recombination break-point hotspot locations. We find that while the locations of recombination break points are not uniformly associated with degrees of nucleotide sequence conservation, they display significant tendencies in multiple coronavirus subgenera to occur in low guanine-cytosine content genome regions, in non-coding regions, at the edges of genes, and at sites within the Spike gene that are predicted to be minimally disruptive of Spike protein folding. While it is apparent that sequence features such as transcriptional regulatory sequences are likely major determinants of where the template-switching events that yield recombination break points most commonly occur, it is evident that selection against misfolded recombinant proteins also strongly impacts observable recombination break-point distributions in coronavirus genomes sampled from nature.
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Affiliation(s)
- Arné de Klerk
- Institute of Infectious Diseases and Molecular Medicine, Division Of Computational Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7701, South Africa
| | - Phillip Swanepoel
- Institute of Infectious Diseases and Molecular Medicine, Division Of Computational Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7701, South Africa
| | - Rentia Lourens
- Division of Neurosurgery, Neuroscience Institute, Department of Surgery, University of Cape Town, Cape Town, 7701, South Africa
| | - Mpumelelo Zondo
- Institute of Infectious Diseases and Molecular Medicine, Division Of Computational Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7701, South Africa
| | - Isaac Abodunran
- Institute of Infectious Diseases and Molecular Medicine, Division Of Computational Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7701, South Africa
| | - Spyros Lytras
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK
| | - Oscar A MacLean
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK
| | - David Robertson
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK
| | - Sergei L Kosakovsky Pond
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Jordan D Zehr
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Venkatesh Kumar
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 14186, Sweden
| | - Michael J Stanhope
- Department of Population and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Gordon Harkins
- South African National Bioinformatics Institute, University of the Western Cape, Cape Town, 7535, South Africa
| | - Ben Murrell
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 14186, Sweden
| | - Darren P Martin
- Institute of Infectious Diseases and Molecular Medicine, Division Of Computational Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7701, South Africa
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8
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Bernard AM, Finnegan KA, Pavinski Bitar P, Stanhope MJ, Shivji MS. Genomic assessment of global population structure in a highly migratory and habitat versatile apex predator, the tiger shark (Galeocerdo cuvier). J Hered 2021; 112:497-507. [PMID: 34374783 DOI: 10.1093/jhered/esab046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 08/09/2021] [Indexed: 11/12/2022] Open
Abstract
Understanding the population dynamics of highly mobile, widely distributed, oceanic sharks, many of which are overexploited, is necessary to aid their conservation management. We investigated the global population genomics of tiger sharks (Galeocerdo cuvier), a circumglobally distributed, apex predator displaying remarkable behavioral versatility in its diet, habitat use (near coastal, coral reef, pelagic), and individual movement patterns (spatially resident to long-distance migrations). We genotyped 242 tiger sharks from 10 globally distributed locations at more than 2000 single nucleotide polymorphisms. Although this species often conducts massive distance migrations, the data show strong genetic differentiation at both neutral (FST=0.125-0.144) and candidate outlier loci (FST=0.570-0.761) between western Atlantic and Indo-Pacific sharks, suggesting the potential for adaptation to the environments specific to these oceanic regions. Within these regions, there was mixed support for population differentiation between northern and southern hemispheres in the western Atlantic, and none for structure within the Indian Ocean. Notably, the results demonstrate a low level of population differentiation of tiger sharks from the remote Hawaiian archipelago compared to sharks from the Indian Ocean (FST=0.003-0.005, P<0.01). Given concerns about biodiversity loss and marine ecosystem impacts caused by overfishing of oceanic sharks in the midst of rapid environmental change, our results suggest it imperative that international fishery management prioritize conservation of the evolutionary potential of the highly genetically differentiated Atlantic and Indo-Pacific populations of this unique apex predator. Furthermore, we suggest targeted management attention to tiger sharks in the Hawaiian archipelago based on a precautionary biodiversity conservation perspective.
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Affiliation(s)
- Andrea M Bernard
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
| | - Kimberly A Finnegan
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA.,Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
| | - Paulina Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Mahmood S Shivji
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA.,Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
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9
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Stout AE, Millet JK, Stanhope MJ, Whittaker GR. Furin cleavage sites in the spike proteins of bat and rodent coronaviruses: Implications for virus evolution and zoonotic transfer from rodent species. One Health 2021; 13:100282. [PMID: 34179330 PMCID: PMC8216856 DOI: 10.1016/j.onehlt.2021.100282] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 12/02/2022] Open
Abstract
Bats and rodents comprise two of the world's largest orders of mammals and the order Chiroptera (bats) has been implicated as a major reservoir of coronaviruses in nature and a source of zoonotic transfer to humans. However, the order Rodentia (rodents) also harbors coronaviruses, with two human coronaviruses (HCoV-OC43 and HCoV-HKU1) considered to have rodent origins. The coronavirus spike protein mediates viral entry and is a major determinant of viral tropism; importantly, the spike protein is activated by host cell proteases at two distinct sites, designated as S1/S2 and S2’. SARS-CoV-2, which is considered to be of bat origin, contains a cleavage site for the protease furin at S1/S2, absent from the rest of the currently known betacoronavirus lineage 2b coronaviruses (Sarbecoviruses). This cleavage site is thought to be critical to its replication and pathogenesis, with a notable link to virus transmission. Here, we examine the spike protein across coronaviruses identified in both bat and rodent species and address the role of furin as an activating protease. Utilizing two publicly available furin prediction algorithms (ProP and PiTou) and based on spike sequences reported in GenBank, we show that the S1/S2 furin cleavage site is typically not present in bat virus spike proteins but is common in rodent-associated sequences, and suggest this may have implications for zoonotic transfer. We provide a phylogenetic history of the Embecoviruses (betacoronavirus lineage 2a), including context for the use of furin as an activating protease for the viral spike protein. From a One Health perspective, continued rodent surveillance should be an important consideration in uncovering novel circulating coronaviruses.
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Affiliation(s)
- Alison E Stout
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA
| | - Jean K Millet
- Université Paris-Saclay, INRAE, UVSQ, Virologie et Immunologie Moléculaires, 78352, Jouy-en-Josas, France
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Gary R Whittaker
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA.,Master of Public Health Program, Cornell University, Ithaca, NY, USA
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10
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Richards VP, Velsko IM, Alam MT, Zadoks RN, Manning SD, Pavinski Bitar PD, Hassler HB, Crestani C, Springer GH, Probert BM, Town CD, Stanhope MJ. Population Gene Introgression and High Genome Plasticity for the Zoonotic Pathogen Streptococcus agalactiae. Mol Biol Evol 2019; 36:2572-2590. [PMID: 31350563 PMCID: PMC6805230 DOI: 10.1093/molbev/msz169] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 04/04/2019] [Accepted: 07/18/2019] [Indexed: 01/06/2023] Open
Abstract
The influence that bacterial adaptation (or niche partitioning) within species has on gene spillover and transmission among bacterial populations occupying different niches is not well understood. Streptococcus agalactiae is an important bacterial pathogen that has a taxonomically diverse host range making it an excellent model system to study these processes. Here, we analyze a global set of 901 genome sequences from nine diverse host species to advance our understanding of these processes. Bayesian clustering analysis delineated 12 major populations that closely aligned with niches. Comparative genomics revealed extensive gene gain/loss among populations and a large pan genome of 9,527 genes, which remained open and was strongly partitioned among niches. As a result, the biochemical characteristics of 11 populations were highly distinctive (significantly enriched). Positive selection was detected and biochemical characteristics of the dispensable genes under selection were enriched in ten populations. Despite the strong gene partitioning, phylogenomics detected gene spillover. In particular, tetracycline resistance (which likely evolved in the human-associated population) from humans to bovine, canines, seals, and fish, demonstrating how a gene selected in one host can ultimately be transmitted into another, and biased transmission from humans to bovines was confirmed with a Bayesian migration analysis. Our findings show high bacterial genome plasticity acting in balance with selection pressure from distinct functional requirements of niches that is associated with an extensive and highly partitioned dispensable genome, likely facilitating continued and expansive adaptation.
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Affiliation(s)
- Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | - Irina M Velsko
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Md Tauqeer Alam
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL
| | - Ruth N Zadoks
- Pentlands Science Park, Moredun Research Institute, Penicuik, United Kingdom
- Institute for Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Shannon D Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, E. Lansing, MI
| | - Paulina D Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Hayley B Hassler
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | - Chiara Crestani
- Pentlands Science Park, Moredun Research Institute, Penicuik, United Kingdom
| | - Garrett H Springer
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | - Brett M Probert
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | | | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
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11
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Bernard AM, Richards VP, Stanhope MJ, Shivji MS. Transcriptome-Derived Microsatellites Demonstrate Strong Genetic Differentiation in Pacific White Sharks. J Hered 2019; 109:771-779. [PMID: 30204894 DOI: 10.1093/jhered/esy045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 09/08/2018] [Indexed: 01/25/2023] Open
Abstract
Recent advances in genome-scale sequencing technology have allowed the development of high resolution genetic markers for the study of nonmodel taxa. In particular, transcriptome sequencing has proven to be highly useful in generating genomic markers for use in population genetic studies, allowing for insight into species connectivity, as well as local adaptive processes as many transcriptome-derived markers are found within or associated with functional genes. Herein, we developed a set of 30 microsatellite markers from a heart transcriptome for the white shark (Carcharodon carcharias), a widely distributed and globally vulnerable marine predator. Using these markers as well as 10 published anonymous genomic microsatellite loci, we provide 1) the first nuclear genetic assessment of the cross-Pacific connectivity of white sharks, and 2) a comparison of the levels of inferred differentiation across microsatellite marker sets (i.e., transcriptome vs. anonymous) to assess their respective utility to elucidate the population genetic dynamics of white sharks. Significant (FST = 0.083, P = 0.05; G″ST = 0.200; P = 0.001) genetic differentiation was found between Southwestern Pacific (n = 19) and Northeastern Pacific (n = 20) white sharks, indicating restricted, cross Pacific gene flow in this species. Transcriptome-derived microsatellite marker sets identified much higher (up to 2×) levels of genetic differentiation than anonymous genomic markers, underscoring potential utility of transcriptome markers in identifying subtle population genetic differences within highly vagile, globally distributed marine species.Subject areas: Population structure and phylogeography; Conservation genetics and biodiversity.
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Affiliation(s)
- Andrea M Bernard
- Save Our Seas Shark Research Center & Guy Harvey Research Institute, Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, North Ocean Drive, Dania Beach, FL
| | - Vincent P Richards
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Mahmood S Shivji
- Save Our Seas Shark Research Center & Guy Harvey Research Institute, Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, North Ocean Drive, Dania Beach, FL
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12
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Gorman J, Marra N, Shivji MS, Stanhope MJ. The complete mitochondrial genome of an Atlantic Ocean Shortfin Mako Shark, Isurus oxyrinchus. Mitochondrial DNA B Resour 2019; 4:3642-3643. [PMID: 33366122 PMCID: PMC7707436 DOI: 10.1080/23802359.2019.1677524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We report the first complete mitochondrial genome of a shortfin mako shark from the Atlantic Ocean. The genome had 16,700 base pairs and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a non-coding D-loop. There were 81 individual differences compared to the published mitochondrial genome of a shortfin mako from the Pacific Ocean, with most variability found in protein coding genes, especially ND5, ND3, and ND1. These highly variable genes may be useful population markers in future studies, and availability of a second mitogenome will assist with future, genome-scale studies of this IUCN Endangered species.
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Affiliation(s)
- Jonathan Gorman
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Nicholas Marra
- Department of Biology, Drury University, Springfield, MO, USA
| | - Mahmood S Shivji
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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13
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Ruck CL, Marra N, Shivji MS, Stanhope MJ. The complete mitochondrial genome of the endangered great hammerhead shark, Sphyrna mokarran. Mitochondrial DNA B Resour 2017; 2:246-248. [PMID: 33473787 PMCID: PMC7800654 DOI: 10.1080/23802359.2017.1318682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We present the first mitochondrial genome sequence of the great hammerhead shark, Sphyrna mokarran. This species is of considerable conservation concern throughout its global distribution, and currently listed as Endangered on the IUCN Red List. The mitochondrial genome is 16,719 bp in length with 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a non-coding control region. The gene arrangement is congruent with other shark and most vertebrate species. This S. mokarran mitogenome provides a genomic resource for assisting with population studies and conservation efforts for this highly depleted species.
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Affiliation(s)
- Cassandra L Ruck
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA
| | - Nicholas Marra
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA.,Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Mahmood S Shivji
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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14
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Marra NJ, Richards VP, Early A, Bogdanowicz SM, Pavinski Bitar PD, Stanhope MJ, Shivji MS. Comparative transcriptomics of elasmobranchs and teleosts highlight important processes in adaptive immunity and regional endothermy. BMC Genomics 2017; 18:87. [PMID: 28132643 PMCID: PMC5278576 DOI: 10.1186/s12864-016-3411-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 12/12/2016] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Comparative genomic and/or transcriptomic analyses involving elasmobranchs remain limited, with genome level comparisons of the elasmobranch immune system to that of higher vertebrates, non-existent. This paper reports a comparative RNA-seq analysis of heart tissue from seven species, including four elasmobranchs and three teleosts, focusing on immunity, but concomitantly seeking to identify genetic similarities shared by the two lamnid sharks and the single billfish in our study, which could be linked to convergent evolution of regional endothermy. RESULTS Across seven species, we identified an average of 10,877 Swiss-Prot annotated genes from an average of 32,474 open reading frames within each species' heart transcriptome. About half of these genes were shared between all species while the remainder included functional differences between our groups of interest (elasmobranch vs. teleost and endotherms vs. ectotherms) as revealed by Gene Ontology (GO) and selection analyses. A repeatedly represented functional category, in both the uniquely expressed elasmobranch genes (total of 259) and the elasmobranch GO enrichment results, involved antibody-mediated immunity, either in the recruitment of immune cells (Fc receptors) or in antigen presentation, including such terms as "antigen processing and presentation of exogenous peptide antigen via MHC class II", and such genes as MHC class II, HLA-DPB1. Molecular adaptation analyses identified three genes in elasmobranchs with a history of positive selection, including legumain (LGMN), a gene with roles in both innate and adaptive immunity including producing antigens for presentation by MHC class II. Comparisons between the endothermic and ectothermic species revealed an enrichment of GO terms associated with cardiac muscle contraction in endotherms, with 19 genes expressed solely in endotherms, several of which have significant roles in lipid and fat metabolism. CONCLUSIONS This collective comparative evidence provides the first multi-taxa transcriptomic-based perspective on differences between elasmobranchs and teleosts, and suggests various unique features associated with the adaptive immune system of elasmobranchs, pointing in particular to the potential importance of MHC Class II. This in turn suggests that expanded comparative work involving additional tissues, as well as genome sequencing of multiple elasmobranch species would be productive in elucidating the regulatory and genome architectural hallmarks of elasmobranchs.
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Affiliation(s)
- Nicholas J Marra
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.,Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL, 33004, USA
| | - Vincent P Richards
- Department of Biological Sciences, Clemson University, Clemson, SC, 29634, USA
| | - Angela Early
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Steve M Bogdanowicz
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Paulina D Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.
| | - Mahmood S Shivji
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL, 33004, USA.
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15
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Jacob AS, Andersen LO, Bitar PP, Richards VP, Shah S, Stanhope MJ, Stensvold CR, Clark CG. Blastocystis Mitochondrial Genomes Appear to Show Multiple Independent Gains and Losses of Start and Stop Codons. Genome Biol Evol 2016; 8:3340-3350. [PMID: 27811175 PMCID: PMC5203790 DOI: 10.1093/gbe/evw255] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Complete mitochondrion-related organelle (MRO) genomes of several subtypes (STs) of the unicellular stramenopile Blastocystis are presented. Complete conservation of gene content and synteny in gene order is observed across all MRO genomes, comprising 27 protein coding genes, 2 ribosomal RNA genes, and 16 transfer RNA (tRNA) genes. Despite the synteny, differences in the degree of overlap between genes were observed between subtypes and also between isolates within the same subtype. Other notable features include unusual base-pairing mismatches in the predicted secondary structures of some tRNAs. Intriguingly, the rps4 gene in some MRO genomes is missing a start codon and, based on phylogenetic relationships among STs, this loss has happened twice independently. One unidentified open reading frame (orf160) is present in all MRO genomes. However, with the exception of ST4 where the feature has been lost secondarily, orf160 contains variously one or two in-frame stop codons. The overall evidence suggests that both the orf160 and rps4 genes are functional in all STs, but how they are expressed remains unclear.
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Affiliation(s)
- Alison S Jacob
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Present address: Faculty of Natural Sciences, Imperial College, London, United Kingdom
| | - Lee O'Brien Andersen
- Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | - Paulina Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY.,Present address: Department of Biological Sciences, College of Agriculture, Forestry and Life Sciences, Clemson University, Clemson, SC
| | - Sarah Shah
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - C Rune Stensvold
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | - C Graham Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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16
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Marra NJ, Wang M, Sun Q, Pavinski Bitar PD, Stanhope MJ, Shivji MS. Mitochondrial genome of an Atlantic white shark ( Carcharodon carcharias). Mitochondrial DNA B Resour 2016; 1:717-719. [PMID: 33473604 PMCID: PMC7799651 DOI: 10.1080/23802359.2016.1222248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/05/2016] [Indexed: 10/24/2022] Open
Abstract
Here we report the first full mitochondrial genome sequence for a white shark caught in the Atlantic Ocean. The mitochondrial genome is 16,745 bp in length and contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding control region. The base composition of this mtDNA lineage is A: 30.7%, C: 26.9%, G: 13.8%, and T: 28.6%. In concordance with previous population genetic studies, the Atlantic caught individual forms a separate lineage from individuals caught on either side of the Pacific Ocean.
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Affiliation(s)
- Nicholas J. Marra
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA
| | - Minghui Wang
- Computational Biology Service Unit, Biotechnology Resource Center, Cornell University, Ithaca, NY, USA
| | - Qi Sun
- Computational Biology Service Unit, Biotechnology Resource Center, Cornell University, Ithaca, NY, USA
| | - Paulina D. Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael J. Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Mahmood S. Shivji
- Save Our Seas Shark Research Center and Guy Harvey Research Institute, Nova Southeastern University, Dania Beach, FL, USA
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17
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Lutz HL, Marra NJ, Grewe F, Carlson JS, Palinauskas V, Valkiūnas G, Stanhope MJ. Laser capture microdissection microscopy and genome sequencing of the avian malaria parasite, Plasmodium relictum. Parasitol Res 2016; 115:4503-4510. [DOI: 10.1007/s00436-016-5237-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 08/26/2016] [Indexed: 11/29/2022]
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18
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Kaspar J, Ahn SJ, Palmer SR, Choi SC, Stanhope MJ, Burne RA. A unique open reading frame within the comX gene of Streptococcus mutans regulates genetic competence and oxidative stress tolerance. Mol Microbiol 2015; 96:463-82. [PMID: 25620525 DOI: 10.1111/mmi.12948] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2015] [Indexed: 01/19/2023]
Abstract
Streptococcus mutans displays complex regulation of genetic competence, with ComX controlling late competence gene transcription. The rcrRPQ operon has been shown to link oxidative stress tolerance, (p)ppGpp metabolism and competence in S. mutans. Importantly, an rcrR polar (ΔrcrR-P) mutant is hyper-transformable, but an rcrR non-polar (ΔrcrR-NP) mutant cannot be transformed. Transcriptome comparisons of the rcrR mutants using RNA-Seq and quantitative real-time polymerase chain reaction revealed little expression in the 5' region of comX in ΔrcrR-NP, but high level expression in the 3' region. Northern blotting with comX probes revealed two distinct transcripts in the ΔrcrR-P and ΔrcrR-NP strains, and 5' Rapid Amplification of cDNA Ends mapped the 5' terminus of the shorter transcript to nt +140 of the comX structural gene, where a unique 69-aa open reading frame, termed XrpA, was encoded in a different reading frame than ComX. Two single-nucleotide substitution mutants (comX::T162C; comX::T210A) were introduced to disrupt XrpA without affecting the sequence of ComX. When the mutations were in the ΔrcrR-NP genetic background, ComX production and transformation were restored. Overexpression of xrpA led to impaired growth in aerobic conditions and decreased transformability. These results reveal an unprecedented mechanism for competence regulation and stress tolerance by a gene product encoded within the comX gene that appears unique to S. mutans.
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Affiliation(s)
- Justin Kaspar
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, 32610, USA
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19
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Richards VP, Palmer SR, Pavinski Bitar PD, Qin X, Weinstock GM, Highlander SK, Town CD, Burne RA, Stanhope MJ. Phylogenomics and the dynamic genome evolution of the genus Streptococcus. Genome Biol Evol 2015; 6:741-53. [PMID: 24625962 PMCID: PMC4007547 DOI: 10.1093/gbe/evu048] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The genus Streptococcus comprises important pathogens that have a severe impact on human health and are responsible for substantial economic losses to agriculture. Here, we utilize 46 Streptococcus genome sequences (44 species), including eight species sequenced here, to provide the first genomic level insight into the evolutionary history and genetic basis underlying the functional diversity of all major groups of this genus. Gene gain/loss analysis revealed a dynamic pattern of genome evolution characterized by an initial period of gene gain followed by a period of loss, as the major groups within the genus diversified. This was followed by a period of genome expansion associated with the origins of the present extant species. The pattern is concordant with an emerging view that genomes evolve through a dynamic process of expansion and streamlining. A large proportion of the pan-genome has experienced lateral gene transfer (LGT) with causative factors, such as relatedness and shared environment, operating over different evolutionary scales. Multiple gene ontology terms were significantly enriched for each group, and mapping terms onto the phylogeny showed that those corresponding to genes born on branches leading to the major groups represented approximately one-fifth of those enriched. Furthermore, despite the extensive LGT, several biochemical characteristics have been retained since group formation, suggesting genomic cohesiveness through time, and that these characteristics may be fundamental to each group. For example, proteolysis: mitis group; urea metabolism: salivarius group; carbohydrate metabolism: pyogenic group; and transcription regulation: bovis group.
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Affiliation(s)
- Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
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Richards VP, Choi SC, Pavinski Bitar PD, Gurjar AA, Stanhope MJ. Transcriptomic and genomic evidence for Streptococcus agalactiae adaptation to the bovine environment. BMC Genomics 2013; 14:920. [PMID: 24369756 PMCID: PMC3890567 DOI: 10.1186/1471-2164-14-920] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 12/21/2013] [Indexed: 11/10/2022] Open
Abstract
Background Streptococcus agalactiae is a major cause of bovine mastitis, which is the dominant health disorder affecting milk production within the dairy industry and is responsible for substantial financial losses to the industry worldwide. However, there is considerable evidence for host adaptation (ecotypes) within S. agalactiae, with both bovine and human sourced isolates showing a high degree of distinctiveness, suggesting differing ability to cause mastitis. Here, we (i) generate RNAseq data from three S. agalactiae isolates (two putative bovine adapted and one human) and (ii) compare publicly available whole genome shotgun sequence data from an additional 202 isolates, obtained from six host species, to elucidate possible genetic factors/adaptations likely important for S. agalactiae growth and survival in the bovine mammary gland. Results Tests for differential expression showed distinct expression profiles for the three isolates when grown in bovine milk. A key finding for the two putatively bovine adapted isolates was the up regulation of a lactose metabolism operon (Lac.2) that was strongly correlated with the bovine environment (all 36 bovine sourced isolates on GenBank possessed the operon, in contrast to only 8/151 human sourced isolates). Multi locus sequence typing of all genome sequences and phylogenetic analysis using conserved operon genes from 44 S. agalactiae isolates and 16 additional Streptococcus species provided strong evidence for acquisition of the operon via multiple lateral gene transfer events, with all Streptococcus species known to be major causes of mastitis, identified as possible donors. Furthermore, lactose fermentation tests were only positive for isolates possessing Lac.2. Combined, these findings suggest that lactose metabolism is likely an important adaptation to the bovine environment. Additional up regulation in the bovine adapted isolates included genes involved in copper homeostasis, metabolism of purine, pyrimidine, glycerol and glucose, and possibly aminoglycoside antibiotic resistance. Conclusion We detected several genetic factors likely important in S. agalactiae’s adaptation to the bovine environment, in particular lactose metabolism. Of concern is the up regulation of a putative antibiotic resistance gene (GCN5-related N-acetyltransferase) that might reflect an adaptation to the use of aminoglycoside antibiotics within this environment.
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Affiliation(s)
| | | | | | | | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
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21
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Palmer SR, Miller JH, Abranches J, Zeng L, Lefebure T, Richards VP, Lemos JA, Stanhope MJ, Burne RA. Phenotypic heterogeneity of genomically-diverse isolates of Streptococcus mutans. PLoS One 2013; 8:e61358. [PMID: 23613838 PMCID: PMC3628994 DOI: 10.1371/journal.pone.0061358] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 03/07/2013] [Indexed: 11/18/2022] Open
Abstract
High coverage, whole genome shotgun (WGS) sequencing of 57 geographically- and genetically-diverse isolates of Streptococcus mutans from individuals of known dental caries status was recently completed. Of the 57 sequenced strains, fifteen isolates, were selected based primarily on differences in gene content and phenotypic characteristics known to affect virulence and compared with the reference strain UA159. A high degree of variability in these properties was observed between strains, with a broad spectrum of sensitivities to low pH, oxidative stress (air and paraquat) and exposure to competence stimulating peptide (CSP). Significant differences in autolytic behavior and in biofilm development in glucose or sucrose were also observed. Natural genetic competence varied among isolates, and this was correlated to the presence or absence of competence genes, comCDE and comX, and to bacteriocins. In general strains that lacked the ability to become competent possessed fewer genes for bacteriocins and immunity proteins or contained polymorphic variants of these genes. WGS sequence analysis of the pan-genome revealed, for the first time, components of a Type VII secretion system in several S. mutans strains, as well as two putative ORFs that encode possible collagen binding proteins located upstream of the cnm gene, which is associated with host cell invasiveness. The virulence of these particular strains was assessed in a wax-worm model. This is the first study to combine a comprehensive analysis of key virulence-related phenotypes with extensive genomic analysis of a pathogen that evolved closely with humans. Our analysis highlights the phenotypic diversity of S. mutans isolates and indicates that the species has evolved a variety of adaptive strategies to persist in the human oral cavity and, when conditions are favorable, to initiate disease.
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Affiliation(s)
- Sara R. Palmer
- Department of Oral Biology, University of Florida, Gainesville, Florida, United States of America
| | - James H. Miller
- Center for Oral Biology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Jacqueline Abranches
- Center for Oral Biology, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Lin Zeng
- Department of Oral Biology, University of Florida, Gainesville, Florida, United States of America
| | - Tristan Lefebure
- Université de Lyon, CNRS, Ecologie des Hydrosystèmes Naturels et Anthropisés; Université Lyon, Villeurbanne, France
- Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Vincent P. Richards
- Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - José A. Lemos
- Center for Oral Biology, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Michael J. Stanhope
- Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Robert A. Burne
- Department of Oral Biology, University of Florida, Gainesville, Florida, United States of America
- * E-mail:
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Burne RA, Zeng L, Ahn SJ, Palmer SR, Liu Y, Lefebure T, Stanhope MJ, Nascimento MM. Progress dissecting the oral microbiome in caries and health. Adv Dent Res 2013; 24:77-80. [PMID: 22899685 DOI: 10.1177/0022034512449462] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent rapid advances in "-omics" technologies have yielded new insights into the interaction of the oral microbiome with its host. Associations of species that are usually considered to be acid-tolerant with caries have been confirmed, while some recognized as health-associated are often present in greater proportions in the absence of caries. In addition, some newly identified bacteria have been suggested as potential contributors to the caries process. In spite of this progress, two major challenges remain. The first is that there is a great deal of heterogeneity in the phenotypic capabilities of individual species of oral bacteria. The second is that the most abundant taxa in oral biofilms display remarkable phenotypic plasticity, i.e., the bacteria associated most strongly with health or with caries can morph rapidly in response to alterations in environmental pH, carbohydrate availability and source, and oxygen tension and redox environment. However, new technologic advances coupled with "old-fashioned microbiology" are starting to erode the barriers to a more complete understanding of oral biofilm physiology and ecology, and in doing so are beginning to provide insights for the creation of novel cost-effective caries control therapies.
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Affiliation(s)
- R A Burne
- Department of Oral Biology, University of Florida College of Dentistry, 1395 Center Drive, Gainesville, FL 32610, USA.
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Cornejo OE, Lefébure T, Pavinski Bitar PD, Lang P, Richards VP, Eilertson K, Do T, Beighton D, Zeng L, Ahn SJ, Burne RA, Siepel A, Bustamante CD, Stanhope MJ. Evolutionary and population genomics of the cavity causing bacteria Streptococcus mutans. Mol Biol Evol 2013; 30:881-93. [PMID: 23228887 PMCID: PMC3603310 DOI: 10.1093/molbev/mss278] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Streptococcus mutans is widely recognized as one of the key etiological agents of human dental caries. Despite its role in this important disease, our present knowledge of gene content variability across the species and its relationship to adaptation is minimal. Estimates of its demographic history are not available. In this study, we generated genome sequences of 57 S. mutans isolates, as well as representative strains of the most closely related species to S. mutans (S. ratti, S. macaccae, and S. criceti), to identify the overall structure and potential adaptive features of the dispensable and core components of the genome. We also performed population genetic analyses on the core genome of the species aimed at understanding the demographic history, and impact of selection shaping its genetic variation. The maximum gene content divergence among strains was approximately 23%, with the majority of strains diverging by 5-15%. The core genome consisted of 1,490 genes and the pan-genome approximately 3,296. Maximum likelihood analysis of the synonymous site frequency spectrum (SFS) suggested that the S. mutans population started expanding exponentially approximately 10,000 years ago (95% confidence interval [CI]: 3,268-14,344 years ago), coincidental with the onset of human agriculture. Analysis of the replacement SFS indicated that a majority of these substitutions are under strong negative selection, and the remainder evolved neutrally. A set of 14 genes was identified as being under positive selection, most of which were involved in either sugar metabolism or acid tolerance. Analysis of the core genome suggested that among 73 genes present in all isolates of S. mutans but absent in other species of the mutans taxonomic group, the majority can be associated with metabolic processes that could have contributed to the successful adaptation of S. mutans to its new niche, the human mouth, and with the dietary changes that accompanied the origin of agriculture.
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Affiliation(s)
- Omar E. Cornejo
- Department of Genetics, School of Medicine, Stanford University
| | - Tristan Lefébure
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
| | - Paulina D. Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
| | - Ping Lang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
| | - Vincent P. Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
| | - Kirsten Eilertson
- Department of Biological Statistics and Computational Biology, Cornell University
| | - Thuy Do
- Department of Microbiology, King’s College London Dental Institute and NIHR Biomedical Research Centre at Guy's and St. Thomas’s NHS Foundation Trust, Guy’s Hospital, London, United Kingdom
| | - David Beighton
- Department of Microbiology, King’s College London Dental Institute and NIHR Biomedical Research Centre at Guy's and St. Thomas’s NHS Foundation Trust, Guy’s Hospital, London, United Kingdom
| | - Lin Zeng
- Department of Oral Biology, University of Florida
| | | | | | - Adam Siepel
- Department of Biological Statistics and Computational Biology, Cornell University
| | | | - Michael J. Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University
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Zeng L, Choi SC, Danko CG, Siepel A, Stanhope MJ, Burne RA. Gene regulation by CcpA and catabolite repression explored by RNA-Seq in Streptococcus mutans. PLoS One 2013; 8:e60465. [PMID: 23555977 PMCID: PMC3610829 DOI: 10.1371/journal.pone.0060465] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/25/2013] [Indexed: 12/20/2022] Open
Abstract
A bacterial transcriptome of the primary etiological agent of human dental caries, Streptococcus mutans, is described here using deep RNA sequencing. Differential expression profiles of the transcriptome in the context of carbohydrate source, and of the presence or absence of the catabolite control protein CcpA, revealed good agreement with previously-published DNA microarrays. In addition, RNA-seq considerably expanded the repertoire of DNA sequences that showed statistically-significant changes in expression as a function of the presence of CcpA and growth carbohydrate. Novel mRNAs and small RNAs were identified, some of which were differentially expressed in conditions tested in this study, suggesting that the function of the S. mutans CcpA protein and the influence of carbohydrate sources has a more substantial impact on gene regulation than previously appreciated. Likewise, the data reveal that the mechanisms underlying prioritization of carbohydrate utilization are more diverse than what is currently understood. Collectively, this study demonstrates the validity of RNA-seq as a potentially more-powerful alternative to DNA microarrays in studying gene regulation in S. mutans because of the capacity of this approach to yield a more precise landscape of transcriptomic changes in response to specific mutations and growth conditions.
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Affiliation(s)
- Lin Zeng
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, United States of America
| | - Sang Chul Choi
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York, United States of America
| | - Charles G. Danko
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York, United States of America
| | - Adam Siepel
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York, United States of America
| | - Michael J. Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Robert A. Burne
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, Florida, United States of America
- * E-mail:
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Zeng L, Xue P, Stanhope MJ, Burne RA. A galactose-specific sugar: phosphotransferase permease is prevalent in the non-core genome of Streptococcus mutans. Mol Oral Microbiol 2013; 28:292-301. [PMID: 23421335 DOI: 10.1111/omi.12025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2013] [Indexed: 12/01/2022]
Abstract
Three genes predicted to encode the A, B and C domains of a sugar : phosphotransferase system (PTS) permease specific for galactose\(EII(Gal) ) were identified in the genomes of 35 of 57 recently sequenced isolates of Streptococcus mutans, the primary etiological agent of human dental caries. Mutants defective in the EII(Gal) complex were constructed in six of the isolates and showed markedly reduced growth rates on galactose-based medium relative to the parental strains. An EII(Gal) -deficient strain constructed using the invasive serotype f strain OMZ175 (OMZ/IIGal) expressed significantly lower PTS activity when galactose was present as the substrate. Galactose was shown to be an effective inducer of catabolite repression in OMZ175, but not in the EII(Gal) -deficient strain. In a mixed-species competition assay with galactose as the sole carbohydrate source, OMZ/IIGal was less effective than the parental strain at competing with the oral commensal bacterium Streptococcus gordonii, which has a high-affinity galactose transporter. Hence, a significant proportion of S. mutans strains encode a galactose PTS permease that could enhance the ability of these isolates to compete more effectively with commensal streptococci for galactose in salivary constituents and the diet.
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Affiliation(s)
- L Zeng
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL 32610, USA
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26
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Richards VP, Zadoks RN, Pavinski Bitar PD, Lefébure T, Lang P, Werner B, Tikofsky L, Moroni P, Stanhope MJ. Genome characterization and population genetic structure of the zoonotic pathogen, Streptococcus canis. BMC Microbiol 2012; 12:293. [PMID: 23244770 PMCID: PMC3541175 DOI: 10.1186/1471-2180-12-293] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 12/06/2012] [Indexed: 11/18/2022] Open
Abstract
Background Streptococcus canis is an important opportunistic pathogen of dogs and cats that can also infect a wide range of additional mammals including cows where it can cause mastitis. It is also an emerging human pathogen. Results Here we provide characterization of the first genome sequence for this species, strain FSL S3-227 (milk isolate from a cow with an intra-mammary infection). A diverse array of putative virulence factors was encoded by the S. canis FSL S3-227 genome. Approximately 75% of these gene sequences were homologous to known Streptococcal virulence factors involved in invasion, evasion, and colonization. Present in the genome are multiple potentially mobile genetic elements (MGEs) [plasmid, phage, integrative conjugative element (ICE)] and comparison to other species provided convincing evidence for lateral gene transfer (LGT) between S. canis and two additional bovine mastitis causing pathogens (Streptococcus agalactiae, and Streptococcus dysgalactiae subsp. dysgalactiae), with this transfer possibly contributing to host adaptation. Population structure among isolates obtained from Europe and USA [bovine = 56, canine = 26, and feline = 1] was explored. Ribotyping of all isolates and multi locus sequence typing (MLST) of a subset of the isolates (n = 45) detected significant differentiation between bovine and canine isolates (Fisher exact test: P = 0.0000 [ribotypes], P = 0.0030 [sequence types]), suggesting possible host adaptation of some genotypes. Concurrently, the ancestral clonal complex (54% of isolates) occurred in many tissue types, all hosts, and all geographic locations suggesting the possibility of a wide and diverse niche. Conclusion This study provides evidence highlighting the importance of LGT in the evolution of the bacteria S. canis, specifically, its possible role in host adaptation and acquisition of virulence factors. Furthermore, recent LGT detected between S. canis and human bacteria (Streptococcus urinalis) is cause for concern, as it highlights the possibility for continued acquisition of human virulence factors for this emerging zoonotic pathogen.
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Affiliation(s)
- Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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27
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Lefébure T, Richards VP, Lang P, Pavinski-Bitar P, Stanhope MJ. Gene repertoire evolution of Streptococcus pyogenes inferred from phylogenomic analysis with Streptococcus canis and Streptococcus dysgalactiae. PLoS One 2012; 7:e37607. [PMID: 22666370 PMCID: PMC3364286 DOI: 10.1371/journal.pone.0037607] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 04/24/2012] [Indexed: 01/08/2023] Open
Abstract
Streptococcus pyogenes, is an important human pathogen classified within the pyogenic group of streptococci, exclusively adapted to the human host. Our goal was to employ a comparative evolutionary approach to better understand the genomic events concomitant with S. pyogenes human adaptation. As part of ascertaining these events, we sequenced the genome of one of the potential sister species, the agricultural pathogen S. canis, and combined it in a comparative genomics reconciliation analysis with two other closely related species, Streptococcus dysgalactiae and Streptococcus equi, to determine the genes that were gained and lost during S. pyogenes evolution. Genome wide phylogenetic analyses involving 15 Streptococcus species provided convincing support for a clade of S. equi, S. pyogenes, S. dysgalactiae, and S. canis and suggested that the most likely S. pyogenes sister species was S. dysgalactiae. The reconciliation analysis identified 113 genes that were gained on the lineage leading to S. pyogenes. Almost half (46%) of these gained genes were phage associated and 14 showed significant matches to experimentally verified bacteria virulence factors. Subsequent to the origin of S. pyogenes, over half of the phage associated genes were involved in 90 different LGT events, mostly involving different strains of S. pyogenes, but with a high proportion involving the horse specific pathogen S. equi subsp. equi, with the directionality almost exclusively (86%) in the S. pyogenes to S. equi direction. Streptococcus agalactiae appears to have played an important role in the evolution of S. pyogenes with a high proportion of LGTs originating from this species. Overall the analysis suggests that S. pyogenes adaptation to the human host was achieved in part by (i) the integration of new virulence factors (e.g. speB, and the sal locus) and (ii) the construction of new regulation networks (e.g. rgg, and to some extent speB).
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Affiliation(s)
| | | | | | | | - Michael J. Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
- * E-mail:
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Choi SC, Rasmussen MD, Hubisz MJ, Gronau I, Stanhope MJ, Siepel A. Replacing and additive horizontal gene transfer in Streptococcus. Mol Biol Evol 2012; 29:3309-20. [PMID: 22617954 DOI: 10.1093/molbev/mss138] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The prominent role of Horizontal Gene Transfer (HGT) in the evolution of bacteria is now well documented, but few studies have differentiated between evolutionary events that predominantly cause genes in one lineage to be replaced by homologs from another lineage ("replacing HGT") and events that result in the addition of substantial new genomic material ("additive HGT"). Here in, we make use of the distinct phylogenetic signatures of replacing and additive HGTs in a genome-wide study of the important human pathogen Streptococcus pyogenes (SPY) and its close relatives S. dysgalactiae subspecies equisimilis (SDE) and S. dysgalactiae subspecies dysgalactiae (SDD). Using recently developed statistical models and computational methods, we find evidence for abundant gene flow of both kinds within each of the SPY and SDE clades and of reduced levels of exchange between SPY and SDD. In addition, our analysis strongly supports a pronounced asymmetry in SPY-SDE gene flow, favoring the SPY-to-SDE direction. This finding is of particular interest in light of the recent increase in virulence of pathogenic SDE. We find much stronger evidence for SPY-SDE gene flow among replacing than among additive transfers, suggesting a primary influence from homologous recombination between co-occurring SPY and SDE cells in human hosts. Putative virulence genes are correlated with transfer events, but this correlation is found to be driven by additive, not replacing, HGTs. The genes affected by additive HGTs are enriched for functions having to do with transposition, recombination, and DNA integration, consistent with previous findings, whereas replacing HGTs seen to influence a more diverse set of genes. Additive transfers are also found to be associated with evidence of positive selection. These findings shed new light on the manner in which HGT has shaped pathogenic bacterial genomes.
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Affiliation(s)
- Sang Chul Choi
- Department of Biological Statistics and Computational Biology, Cornell University
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Suzuki H, Stanhope MJ. Functional bias of positively selected genes in Streptococcus genomes. Infect Genet Evol 2011; 12:274-7. [PMID: 22155358 DOI: 10.1016/j.meegid.2011.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 11/07/2011] [Accepted: 11/10/2011] [Indexed: 11/26/2022]
Abstract
Rates of nonsynonymous substitution (dN) significantly higher than rates of synonymous substitution (dS) have been used as evidence of positive selection for the fixation of advantageous point mutations. It has been suggested that positive selection contributes to the evolution of virulence factors and certain functional categories in bacterial pathogens. The genus Streptococcus contains a number of important human and agricultural pathogens. Here we assessed positive selection across 13 Streptococcus species, and their relationship with virulence factors and functional categories. We found that known virulence genes were subject to positive selection pressure as much as other genes. After false discovery rate correction for multiple comparisons, no functional categories were significantly over- or under-represented in positively selected genes relative to other genes. Our results suggest that within the genus Streptococcus positive selection based on dN/dS ratios is not distributed with bias across biological functions.
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Affiliation(s)
- Haruo Suzuki
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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30
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Richards VP, Lang P, Bitar PDP, Lefébure T, Schukken YH, Zadoks RN, Stanhope MJ. Comparative genomics and the role of lateral gene transfer in the evolution of bovine adapted Streptococcus agalactiae. Infect Genet Evol 2011; 11:1263-75. [PMID: 21536150 DOI: 10.1016/j.meegid.2011.04.019] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/12/2011] [Accepted: 04/16/2011] [Indexed: 12/18/2022]
Abstract
In addition to causing severe invasive infections in humans, Streptococcus agalactiae, or group B Streptococcus (GBS), is also a major cause of bovine mastitis. Here we provide the first genome sequence for S. agalactiae isolated from a cow diagnosed with clinical mastitis (strain FSL S3-026). Comparison to eight S. agalactiae genomes obtained from human disease isolates revealed 183 genes specific to the bovine strain. Subsequent polymerase chain reaction (PCR) screening for the presence/absence of a subset of these loci in additional bovine and human strains revealed strong differentiation between the two groups (Fisher exact test: p<0.0001). The majority of the bovine strain-specific genes (∼ 85%) clustered tightly into eight genomic islands, suggesting these genes were acquired through lateral gene transfer (LGT). This bovine GBS also contained an unusually high proportion of insertion sequences (4.3% of the total genome), suggesting frequent genomic rearrangement. Comparison to other mastitis-causing species of bacteria provided strong evidence for two cases of interspecies LGT within the shared bovine environment: bovine S. agalactiae with Streptococcus uberis (nisin U operon) and Streptococcus dysgalactiae subsp. dysgalactiae (lactose operon). We also found evidence for LGT, involving the salivaricin operon, between the bovine S. agalactiae strain and either Streptococcus pyogenes or Streptococcus salivarius. Our findings provide insight into mechanisms facilitating environmental adaptation and acquisition of potential virulence factors, while highlighting both the key role LGT has played in the recent evolution of the bovine S. agalactiae strain, and the importance of LGT among pathogens within a shared environment.
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Affiliation(s)
- Vincent P Richards
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Suzuki H, Lefébure T, Hubisz MJ, Pavinski Bitar P, Lang P, Siepel A, Stanhope MJ. Comparative genomic analysis of the Streptococcus dysgalactiae species group: gene content, molecular adaptation, and promoter evolution. Genome Biol Evol 2011; 3:168-85. [PMID: 21282711 PMCID: PMC3056289 DOI: 10.1093/gbe/evr006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Comparative genomics of closely related bacterial species with different pathogenesis and host preference can provide a means of identifying the specifics of adaptive differences. Streptococcus dysgalactiae (SD) is comprised of two subspecies: S. dysgalactiae subsp. equisimilis is both a human commensal organism and a human pathogen, and S. dysgalactiae subsp. dysgalactiae is strictly an animal pathogen. Here, we present complete genome sequences for both taxa, with analyses involving other species of Streptococcus but focusing on adaptation in the SD species group. We found little evidence for enrichment in biochemical categories of genes carried by each SD strain, however, differences in the virulence gene repertoire were apparent. Some of the differences could be ascribed to prophage and integrative conjugative elements. We identified approximately 9% of the nonrecombinant core genome to be under positive selection, some of which involved known virulence factors in other bacteria. Analyses of proteomes by pooling data across genes, by biochemical category, clade, or branch, provided evidence for increased rates of evolution in several gene categories, as well as external branches of the tree. Promoters were primarily evolving under purifying selection but with certain categories of genes evolving faster. Many of these fast-evolving categories were the same as those associated with rapid evolution in proteins. Overall, these results suggest that adaptation to changing environments and new hosts in the SD species group has involved the acquisition of key virulence genes along with selection of orthologous protein-coding loci and operon promoters.
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Affiliation(s)
- Haruo Suzuki
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
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Lefébure T, Bitar PDP, Suzuki H, Stanhope MJ. Evolutionary dynamics of complete Campylobacter pan-genomes and the bacterial species concept. Genome Biol Evol 2010; 2:646-55. [PMID: 20688752 PMCID: PMC2940326 DOI: 10.1093/gbe/evq048] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Defining bacterial species and understanding the relative cohesiveness of different components of their genomes remains a fundamental problem in microbiology. Bacterial species tend to be comprised of both a set of core and dispensable genes, with the sum of these two components forming the species pan-genome. The role of the core and dispensable genes in defining bacterial species and the question of whether pan-genomes are finite or infinite remain unclear. Here we demonstrate, through the analysis of 96 genome sequences derived from two closely related sympatric sister species of pathogenic bacteria (Campylobacter coli and C. jejuni), that their pan-genome is indeed finite and that there are unique and cohesive features to each of their genomes defining their genomic identity. The two species have a similar pan-genome size; however, C. coli has acquired a larger core genome and each species has evolved a number of species-specific core genes, possibly reflecting different adaptive strategies. Genome-wide assessment of the level of lateral gene transfer within and between the two sister species, as well as within the core and non-core genes, demonstrates a resistance to interspecies recombination in the core genome of the two species and therefore provides persuasive support for the core genome hypothesis for bacterial species.
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Affiliation(s)
- Tristan Lefébure
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, New York, USA
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Lefébure T, Stanhope MJ. Pervasive, genome-wide positive selection leading to functional divergence in the bacterial genus Campylobacter. Genome Res 2009; 19:1224-32. [PMID: 19304960 DOI: 10.1101/gr.089250.108] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
An open question in bacterial genomics is the role that adaptive evolution of the core genome plays in diversification and adaptation of bacterial species, and how this might differ between groups of bacteria occupying different environmental circumstances. The genus Campylobacter encompasses several important human and animal enteric pathogens, with genome sequence data available for eight species. We estimate the Campylobacter core genome at 647 genes, with 92.5% of the nonrecombinant core genome loci under positive selection in at least one lineage and the same gene frequently under positive selection in multiple lineages. Tests are provided that reject recombination, saturation, and variation in codon usage bias as factors contributing to this high level of selection. We suggest this genome-wide adaptive evolution may result from a Red Queen macroevolutionary dynamic, in which species are involved in competition for resources within the mammalian and/or vertebrate gastrointestinal tract. Much reduced levels of positive selection evident in Streptococcus, as reported by the authors in an earlier work, may be a consequence of these taxa inhabiting less species-rich habitats, and more unique niches. Despite many common loci under positive selection in multiple Campylobacter lineages, we found no evidence for molecular adaptive convergence at the level of the same or adjacent codons, or even protein domains. Taken collectively, these results describe the diversification of a bacterial genus that involves pervasive natural selection pressure across virtually the entire genome, with this adaptation occurring in different ways in different lineages, despite the species tendency toward a common gastrointestinal habitat.
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Affiliation(s)
- Tristan Lefébure
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA
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Lang P, Lefébure T, Wang W, Zadoks RN, Schukken Y, Stanhope MJ. Gene content differences across strains of Streptococcus uberis identified using oligonucleotide microarray comparative genomic hybridization. Infect Genet Evol 2008; 9:179-88. [PMID: 19056519 DOI: 10.1016/j.meegid.2008.10.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 10/16/2008] [Accepted: 10/26/2008] [Indexed: 11/29/2022]
Abstract
Streptococcus uberis is one of the principal causative agents of bovine mastitis. The organism is typically considered an environmental pathogen. In this study, two multilocus sequence typing (MLST) schemes and whole genome DNA microarrays were used to evaluate the degree and nature of genome flexibility between S. uberis strains. The 21 isolates examined in this study arise from a collection of 232 international isolates for which previous epidemiological and preliminary genotyping data existed. The microarray analysis resulted in an estimate of the core genome for S. uberis, consisting of 1530 ORFs, among 1855 tested, representing 82.5% of the S. uberis 0140J genome. The remaining ORFs were variable in gene content across the 21 tested strains. A total of 26 regions of difference (RDs), consisting of three or more contiguous ORFs, were identified among the variable genes. Core genes mainly encoded housekeeping functions, while the variable genes primarily fell within categories such as protection responses, degradation of small molecules, laterally acquired elements, and two component systems. Recombination detection procedures involving the MLST loci suggested S. uberis is a highly recombinant species, precluding accurate phylogenetic reconstructions involving these data. On the other hand, the microarray data did provide limited support for an association of gene content with strains found in multiple cows and/or multiple herds, suggesting the possibility of genes related to bovine transmissibility or host-adaptation.
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Affiliation(s)
- Ping Lang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Stanhope MJ, Lefébure T, Walsh SL, Becker JA, Lang P, Pavinski Bitar PD, Miller LA, Italia MJ, Amrine-Madsen H. Positive selection in penicillin-binding proteins 1a, 2b, and 2x from Streptococcus pneumoniae and its correlation with amoxicillin resistance development. Infect Genet Evol 2008; 8:331-9. [PMID: 18394970 DOI: 10.1016/j.meegid.2008.02.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 02/06/2008] [Accepted: 02/08/2008] [Indexed: 11/29/2022]
Abstract
The efficacy of beta-lactam antibiotics in Streptococcus pneumoniae has been compromised because of the development of altered penicillin-binding proteins (PBPs), however, this has been less so for amoxicillin than for penicillin. Recently, there have been a number of important methods developed to detect molecular adaptation in protein coding genes. The purpose of this study is to employ modern molecular selection approaches to predict sites under positive selection pressure in PBPs, derived from a large international S. pneumoniae collection of amoxicillin resistant and susceptible isolates, and encompassing a comparative data set of 354 pbp1a, 335 pbp2b, and 389 pbp2x gene sequences. A correspondence discriminant analysis (CDA) of positively selected pbp sites and amoxicillin MIC (minimum inhibitory concentration) values is then used to detect sites under positive selection pressure that are important in discriminating different amoxicillin MICs. Molecular adaptation was evident throughout PBP2X, with numerous positively selected sites in both the transpeptidase (TP) and C-terminal domains, strongly correlated with discriminating amoxicillin MICs. In the case of PBP1A positive selection was present in the glycosyltransfer (GT), TP and C-terminal domains. Sites within the TP domain tended to be correlated with the discrimination of low from intermediate MICs, whereas sites within the C-terminal tail, with a discrimination of intermediate from fully resistant. Most of the positively selected sites within PBP2B were in the N-terminal domain and were not correlated with amoxicillin MICs, however, several sites taken from the literature for the TP domain were strongly associated with discriminating high from intermediate level amoxicillin resistance. Many of the positively selected sites could be directly associated with functional inferences based on the crystal structures of these proteins. Our results suggest that clinical emphasis on TP domain sequences of these proteins may result in missing information relevant to antibiotic resistance development.
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Affiliation(s)
- Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
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Stanhope MJ, Walsh SL, Becker JA, Miller LA, Lefébure T, Lang P, Bitar PDP, Amrine-Madsen H. The relative frequency of intraspecific lateral gene transfer of penicillin binding proteins 1a, 2b, and 2x, in amoxicillin resistant Streptococcus pneumoniae. Infection, Genetics and Evolution 2007; 7:520-34. [PMID: 17475572 DOI: 10.1016/j.meegid.2007.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2006] [Revised: 03/21/2007] [Accepted: 03/23/2007] [Indexed: 11/18/2022]
Abstract
Evidence exists for both interspecific and intraspecific recombination (lateral gene transfer; LGT) involving Streptococcus pneumoniae pbp (penicillin binding protein) loci. LGT of capsular genes, or serotype switching, is also know to occur between S. pneumoniae of different serotype. It is not clear whether intraspecific pbp LGT is relatively common, whether there is a difference in the relative frequency of intraspecific LGT of different pbps, and whether serotype switching is more or less frequent than pbp LGT. The purpose of this study was to use comparative evolutionary biology analysis of 216 international clinical S. pneumoniae isolates, from the Alexander Project collection, to gain insight on these issues, as well as the possible role they might be playing in spreading amoxicillin resistance. All 216 isolates were genotyped using MLST and complete or nearly complete sequences for pbp1a, pbp2b, and pbp2x were determined. Amoxicillin MICs were available for each isolate. pbps were genotyped using phylogenetics and two or more pbp types within a MLST sequence type (ST) or clonal complex were taken as putative cases of pbp LGT; these hypotheses were statistically evaluated using the approximately unbiased (AU) test. Serotypes were determined for 171 of these isolates and the minimum number of switching events necessary to explain the serotype phenotypes for each of the STs and clonal complexes were evaluated. The majority (78%) of the amoxicillin resistant isolates were comprised in 5 clonal complexes. The relative frequency of pbp LGT was greatest for pbp2b and 2x (minimum of 10.2 and 7.8%, respectively, of the isolates consistent with the LGT hypothesis), followed by 1a (3.9%). Serotype switching was more frequent than intraspecific pbp LGT (33% of isolates consistent with serotype switching hypothesis). Although intraspecific LGT of pbps is occurring and has played a role in the spread of amoxicillin resistance in S. pneumoniae, clonal dissemination appears to be more significant.
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Affiliation(s)
- Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, United States.
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Lefébure T, Stanhope MJ. Evolution of the core and pan-genome of Streptococcus: positive selection, recombination, and genome composition. Genome Biol 2007; 8:R71. [PMID: 17475002 PMCID: PMC1929146 DOI: 10.1186/gb-2007-8-5-r71] [Citation(s) in RCA: 237] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 04/24/2007] [Accepted: 05/02/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The genus Streptococcus is one of the most diverse and important human and agricultural pathogens. This study employs comparative evolutionary analyses of 26 Streptococcus genomes to yield an improved understanding of the relative roles of recombination and positive selection in pathogen adaptation to their hosts. RESULTS Streptococcus genomes exhibit extreme levels of evolutionary plasticity, with high levels of gene gain and loss during species and strain evolution. S. agalactiae has a large pan-genome, with little recombination in its core-genome, while S. pyogenes has a smaller pan-genome and much more recombination of its core-genome, perhaps reflecting the greater habitat, and gene pool, diversity for S. agalactiae compared to S. pyogenes. Core-genome recombination was evident in all lineages (18% to 37% of the core-genome judged to be recombinant), while positive selection was mainly observed during species differentiation (from 11% to 34% of the core-genome). Positive selection pressure was unevenly distributed across lineages and biochemical main role categories. S. suis was the lineage with the greatest level of positive selection pressure, the largest number of unique loci selected, and the largest amount of gene gain and loss. CONCLUSION Recombination is an important evolutionary force in shaping Streptococcus genomes, not only in the acquisition of significant portions of the genome as lineage specific loci, but also in facilitating rapid evolution of the core-genome. Positive selection, although undoubtedly a slower process, has nonetheless played an important role in adaptation of the core-genome of different Streptococcus species to different hosts.
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Affiliation(s)
- Tristan Lefébure
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Richards VP, Thomas JD, Stanhope MJ, Shivji MS. Genetic connectivity in the Florida reef system: comparative phylogeography of commensal invertebrates with contrasting reproductive strategies. Mol Ecol 2006; 16:139-57. [PMID: 17181727 DOI: 10.1111/j.1365-294x.2006.03145.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Effective spatial management of coral reefs including design of marine protected areas requires an understanding of interpopulation genetic connectivity. We assessed gene flow along 355 km of the Florida reef system and between Florida and Belize in three commensal invertebrates occupying the same host sponge (Callyspongia vaginalis) but displaying contrasting reproductive dispersal strategies: the broadcast-spawning brittle star Ophiothrix lineata and two brooding amphipods Leucothoe kensleyi and Leucothoe ashleyae. Multiple analytical approaches to sequence variation in the mitochondrial COI gene demonstrated a high degree of overall connectivity for all three species along the Florida reef system. Ophiothrix lineata showed significant genetic structuring between Florida and Belize, and a pattern of isolation by distance but no significant genetic structuring along the Florida coastline. Bayesian estimates of migration detected a strong southerly dispersal bias for O. lineata along the Florida reef system, contrary to the general assumption of northerly gene flow in this region based on the direction of the Florida Current. Both amphipods, despite direct development, also showed high gene flow along the Florida reef system. Multiple inferences of long-distance dispersal from a nested clade analysis support the hypothesis that amphipod transport, possibly in detached sponge fragments, could generate the high levels of overall gene flow observed. However, this transport mechanism appears much less effective across deep water as connectivity between Florida and Belize (1072 km) is highly restricted.
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Affiliation(s)
- Vincent P Richards
- National Coral Reef Institute, Oceanographic Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL 33004 USA
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Burk-Herrick A, Scally M, Amrine-Madsen H, Stanhope MJ, Springer MS. Natural selection and mammalian BRCA1 sequences: elucidating functionally important sites relevant to breast cancer susceptibility in humans. Mamm Genome 2006; 17:257-70. [PMID: 16518693 DOI: 10.1007/s00335-005-0067-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Accepted: 11/25/2005] [Indexed: 10/25/2022]
Abstract
Comparison of orthologous gene sequences is emerging as a powerful approach to elucidating functionally important positions in human disease genes. Using a diverse array of 132 mammalian BRCA1 (exon 11) sequences, we evaluated the functional significance of specific sites in the context of selection information (purifying, neutral, or diversifying) as well as the ability to extract such information from alignments that index varying degrees of mammalian diversity. Small data sets of either closely related taxa (Primates) or divergent placental taxa were unable to distinguish sites conserved due to purifying selection from sites conserved due to chance (false-positive rate = 65%-99%). Increasing the number of placental taxa to 57 greatly reduced the potential false-positive rate (0%-1.5%). Using the larger data set, we ranked the oncogenic risk of human missense mutations using a novel method that incorporates site-specific selection level and severity of the amino acid change evaluated against the amino acids present in other mammalian taxa. In addition to sites undergoing positive selection in Marsupialia, Laurasiatheria, Euarchontoglires, and Primates, we identified sites most likely to be undergoing divergent selection pressure in different lineages and six pairs of potentially interacting sites. Our results demonstrate the necessity of including large numbers of sequences to elucidate functionally important sites of a protein when using a comparative evolutionary approach.
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Stanhope MJ, Walsh SL, Becker JA, Italia MJ, Ingraham KA, Gwynn MN, Mathie T, Poupard JA, Miller LA, Brown JR, Amrine-Madsen H. Molecular evolution perspectives on intraspecific lateral DNA transfer of topoisomerase and gyrase loci in Streptococcus pneumoniae, with implications for fluoroquinolone resistance development and spread. Antimicrob Agents Chemother 2006; 49:4315-26. [PMID: 16189113 PMCID: PMC1251522 DOI: 10.1128/aac.49.10.4315-4326.2005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fluoroquinolones are an important class of antibiotics for the treatment of infections arising from the gram-positive respiratory pathogen Streptococcus pneumoniae. Although there is evidence supporting interspecific lateral DNA transfer of fluoroquinolone target loci, no studies have specifically been designed to assess the role of intraspecific lateral transfer of these genes in the spread of fluoroquinolone resistance. This study involves a comparative evolutionary perspective, in which the evolutionary history of a diverse set of S. pneumoniae clinical isolates is reconstructed from an expanded multilocus sequence typing data set, with putative recombinants excluded. This control history is then assessed against networks of each of the four fluoroquinolone target loci from the same isolates. The results indicate that although the majority of fluoroquinolone target loci from this set of 60 isolates are consistent with a clonal dissemination hypothesis, 3 to 10% of the sequences are consistent with an intraspecific lateral transfer hypothesis. Also evident were examples of interspecific transfer, with two isolates possessing a parE-parC gene region arising from viridans group streptococci. The Spain 23F-1 clone is the most dominant fluoroquinolone-nonsusceptible clone in this set of isolates, and the analysis suggests that its members act as frequent donors of fluoroquinolone-nonsusceptible loci. Although the majority of fluoroquinolone target gene sequences in this set of isolates can be explained on the basis of clonal dissemination, a significant number are more parsimoniously explained by intraspecific lateral DNA transfer, and in situations of high S. pneumoniae population density, such events could be an important means of resistance spread.
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Abstract
Recent comprehensive studies of DNA sequences support the monophyly of Afrotheria, comprising elephants, sirenians (dugongs and manatees), hyraxes, tenrecs, golden moles, aardvarks, and elephant shrews, as well as that of Paenungulata, comprising elephants, sirenians, and hyraxes. However, phylogenetic relationships among paenungulates, as well as among nonpaenungulates, have remained ambiguous. Here we applied an extensive retroposon analysis to these problems to support the monophyly of aardvarks, tenrecs, and golden moles, with elephant shrews as their sister group. Regarding phylogenetic relationships in Paenungulata, we could characterize only one informative locus, although we could isolate many insertions specific to each of three lineages, namely, Proboscidea, Sirenia, and Hyracoidea. These data prompted us to reexamine phylogenetic relationships among Paenungulata using 19 nuclear gene sequences resulting in three different analyses, namely, short interspersed element (SINE) insertions, nuclear sequence analyses, and morphological cladistics, supporting different respective phylogenies. We concluded that these three lineages diverged very rapidly in a very short evolutionary period, with the consequence that ancestral polymorphism present in the last common ancestor of Paenungulata results in such incongruence. Our results suggest the rapid fixation of many large-scale morphological synapomorphies for Tethytheria; implications of this in relation to the morphological evolution in Paenungulata are discussed.
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Affiliation(s)
- Hidenori Nishihara
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan
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Douzery EJP, Delsuc F, Stanhope MJ, Huchon D. Local molecular clocks in three nuclear genes: divergence times for rodents and other mammals and incompatibility among fossil calibrations. J Mol Evol 2004; 57 Suppl 1:S201-13. [PMID: 15008417 DOI: 10.1007/s00239-003-0028-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Reconstructing the chronology of mammalian evolution is a debated issue between molecule- and fossil-based inferences. A methodological limitation of molecules is the evolutionary rate variation among lineages, precluding the application of the global molecular clock. We considered 2422 first and second codon positions of the combined ADRA2B, IRBP, and vWF nuclear genes for a well-documented set of placentals including an extensive sampling of rodents. Using seven independent calibration points and a maximum-likelihood framework, we evaluated whether molecular and paleontological estimates of mammalian divergence dates may be reconciled by the local molecular clocks approach, allowing local constancy of substitution rates with variations at larger phylogenetic scales. To handle the difficulty of choosing among all possible rate assignments for various lineages, local molecular clocks were based on the results of branch-length and two-cluster tests. Extensive lineage-specific variation of evolutionary rates was detected, even among rodents. Cross-calibrations indicated some incompatibilities between divergence dates based on different paleontological references. To decrease the impact of a single calibration point, estimates derived from independent calibrations displaying only slight reciprocal incompatibility were averaged. The divergence dates inferred for the split between mice and rats (approximately 13-19 Myr) was younger than previously published molecular estimates. The most recent common ancestors of rodents, primates and rodents, boreoeutherians, and placentals were estimated to be, respectively, approximately 60, 70, 75, and 78 Myr old. Global clocks, local clocks, and quartet dating analyses suggested a Late Cretaceous origin of the crown placental clades followed by a Tertiary radiation of some placental orders like rodents.
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Affiliation(s)
- Emmanuel J P Douzery
- Laboratoire de Paléontologie, Paléobiologie et Phylogenie-CC064, Institut des Sciences de l'Evolution UMR 5554/CNRS, Université Montpellier II, Place E. Bataillon, 34 095 Montpellier Cedex 05, France.
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Abstract
Deciphering relationships among the orders of placental mammals remains an important problem in evolutionary biology and has implications for understanding patterns of morphological character evolution, reconstructing the ancestral placental genome, and evaluating the role of plate tectonics and dispersal in the biogeographic history of this group. Until recently, both molecular and morphological studies provided only a limited and questionable resolution of placental relationships. Studies based on larger and more diverse molecular datasets, and using an array of methodological approaches, are now converging on a stable tree topology with four major groups of placental mammals. The emerging tree has revealed numerous instances of convergent evolution and suggests a role for plate tectonics in the early evolutionary history of placental mammals. The reconstruction of mammalian phylogeny illustrates both the pitfalls and the powers of molecular systematics.
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Affiliation(s)
- Mark S Springer
- Department of Biology, University of California, Riverside, CA 92521, USA.
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Stanhope MJ, Brown JR, Amrine-Madsen H. Evidence from the evolutionary analysis of nucleotide sequences for a recombinant history of SARS-CoV. Infect Genet Evol 2004; 4:15-9. [PMID: 15019585 PMCID: PMC7128439 DOI: 10.1016/j.meegid.2003.10.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Revised: 10/24/2003] [Accepted: 10/27/2003] [Indexed: 11/20/2022]
Abstract
The origins and evolutionary history of the Severe Acute Respiratory Syndrome (SARS) coronavirus (SARS-CoV) remain an issue of uncertainty and debate. Based on evolutionary analyses of coronavirus DNA sequences, encompassing an approximately 13 kb stretch of the SARS-TOR2 genome, we provide evidence that SARS-CoV has a recombinant history with lineages of types I and III coronavirus. We identified a minimum of five recombinant regions ranging from 83 to 863 bp in length and including the polymerase, nsp9, nsp10, and nsp14. Our results are consistent with a hypothesis of viral host jumping events, concomitant with the reassortment of bird and mammalian coronaviruses, a scenario analogous to earlier outbreaks of influenzae.
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Affiliation(s)
- Michael J Stanhope
- Bioinformatics Division, Genetics Research, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, USA.
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Douady CJ, Scally M, Springer MS, Stanhope MJ. “Lipotyphlan” phylogeny based on the growth hormone receptor gene: a reanalysis. Mol Phylogenet Evol 2004; 30:778-88. [PMID: 15012955 DOI: 10.1016/s1055-7903(03)00246-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2003] [Revised: 06/11/2003] [Indexed: 11/29/2022]
Abstract
From an evolutionary perspective, "insectivores" have been one of the most important mammalian groups for over a century. Morphologists have successively pruned flying lemurs, elephant shrews, and tree shrews from Insectivora, but have retained chrysochlorids, tenrecs, erinaceids, soricids, talpids, and solenodontids in crown-group Lipotyphla. With the appearance of large molecular data sets, the monophyly of Lipotyphla has proved untenable. Rather, an emerging consensus is that Lipotyphla is a diphyletic taxon comprised of two monophyletic groups, Afrosoricida and Eulipotyphla. A recent paper by Malia et al. [Mol. Phylogenet. Evol. 24 (2002) 91-101] challenged this view and argued that "While the data [Growth Hormone Receptor] were unable to support the orders Lipotyphla, Eulipotyphla, and Tenrecoidea [= Afrosoricida] this was most likely due to the polyphyly of these groups and not to problems associated with the gene itself such as saturation or highly divergent sequences em leader " (p. 100). We analyzed Malia et al.'s original GHR data set (at both nuclear and protein level), an expanded GHR data set that included 49 additional sequences, and a concatenated data set that included GHR, BRCA1, vWF, and A2AB for a diverse selection of lipotyphlan taxa. Although protein analyses proved inconclusive, all analyses at the DNA level clearly show that the statement of Malia et al. is erroneous. Indeed, likelihood analyses with GHR and with the concatenated data set provide more support for Eulipotyphla and Afrosoricida than for competing hypotheses. These results also highlight the potential pitfalls of single-gene and parsimony-only analyses.
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Affiliation(s)
- Christophe J Douady
- Dalhousie University, Department of Biochemistry and Molecular Biology, Halifax, Nova Scotia, Canada.
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de Jong WW, Stanhope MJ, Springer MS. Papers from the symposium “Mammalian Phylogeny,” Sorrento, Italy, June 16, 2002. Mol Phylogenet Evol 2003. [DOI: 10.1016/s1055-7903(03)00216-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Delsuc F, Stanhope MJ, Douzery EJP. Molecular systematics of armadillos (Xenarthra, Dasypodidae): contribution of maximum likelihood and Bayesian analyses of mitochondrial and nuclear genes. Mol Phylogenet Evol 2003; 28:261-75. [PMID: 12878463 DOI: 10.1016/s1055-7903(03)00111-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The 30 living species of armadillos, anteaters, and sloths (Mammalia: Xenarthra) represent one of the three major clades of placentals. Armadillos (Cingulata: Dasypodidae) are the earliest and most speciose xenarthran lineage with 21 described species. The question of their tricky phylogeny was here studied by adding two mitochondrial genes (NADH dehydrogenase subunit 1 [ND1] and 12S ribosomal RNA [12S rRNA]) to the three protein-coding nuclear genes (alpha2B adrenergic receptor [ADRA2B], breast cancer susceptibility exon 11 [BRCA1], and von Willebrand factor exon 28 [VWF]) yielding a total of 6869 aligned nucleotide sites for thirteen xenarthran species. The two mitochondrial genes were characterized by marked excesses of transitions over transversions-with a strong bias toward CT transitions for the 12S rRNA-and exhibited two- to fivefold faster evolutionary rates than the fastest nuclear gene (ADRA2B). Maximum likelihood and Bayesian phylogenetic analyses supported the monophyly of Dasypodinae, Tolypeutinae, and Euphractinae, with the latter two armadillo subfamilies strongly clustering together. Conflicting branching points between individual genes involved relationships within the subfamilies Tolypeutinae and Euphractinae. Owing to a greater number of informative sites, the overall concatenation favored the mitochondrial topology with the classical grouping of Cabassous and Priodontes within Tolypeutinae, and a close relationship between Euphractus and Chaetophractus within Euphractinae. However, low statistical support values associated with almost equal distributions of apomorphies among alternatives suggested that two parallel events of rapid speciation occurred within these two armadillo subfamilies.
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Affiliation(s)
- Frédéric Delsuc
- Laboratoire de Paléontologie, Paléobiologie et Phylogénie, Institut des Sciences de l'Evolution, Université Montpellier II, Montpellier, France
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Amrine-Madsen H, Scally M, Westerman M, Stanhope MJ, Krajewski C, Springer MS. Nuclear gene sequences provide evidence for the monophyly of australidelphian marsupials. Mol Phylogenet Evol 2003; 28:186-96. [PMID: 12878458 DOI: 10.1016/s1055-7903(03)00122-2] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Relationships among the seven extant orders of marsupials remain poorly understood. Most classifications recognize a fundamental split between Ameridelphia, which contains the American orders Didelphimorphia and Paucituberculata, and Australidelphia, which contains four Australasian orders (Dasyuromorphia, Diprotodontia, Notoryctemorphia, and Peramelina) and the South American order Microbiotheria, represented by Dromiciops gliroides. Ameridelphia and Australidelphia are each supported by key morphological characters with dichotomous character states. To date, molecular studies indexing all marsupial orders have reported inconclusive results. However, several studies have suggested that Dromiciops is nested within Australidelphia. This result has important implications for understanding the biogeographic history of living marsupials. To address questions in higher-level marsupial systematics, we sequenced portions of five nuclear genes (Apolipoprotein B gene; Breast and Ovarian cancer susceptibility gene 1; Recombination activating gene 1; Interphotoreceptor retinoid binding protein gene; and von Willebrand factor gene) for representatives of all orders of marsupials, as well as placental outgroups. The resulting 6.4kb concatenation was analyzed using maximum parsimony, distance methods, maximum likelihood, and Bayesian methods. tests were used to examine a priori hypotheses. All analyses provided robust support for the monophyly of Australidelphia (bootstrap support=99-100%; posterior probability=1.00). Ameridelphia received much lower support, although this clade was not rejected in statistical tests. Within Diprotodontia, both Vombatiformes and Phalangeriformes were supported at the 100% bootstrap level and with posterior probabilities of 1.00.
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Brown JR, Gentry D, Becker JA, Ingraham K, Holmes DJ, Stanhope MJ. Horizontal transfer of drug-resistant aminoacyl-transfer-RNA synthetases of anthrax and Gram-positive pathogens. EMBO Rep 2003; 4:692-8. [PMID: 12792655 PMCID: PMC1326320 DOI: 10.1038/sj.embor.embor881] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2003] [Revised: 04/30/2003] [Accepted: 05/13/2003] [Indexed: 11/08/2022] Open
Abstract
The screening of new antibiotics against several bacterial strains often reveals unexpected occurrences of natural drug resistance. Two examples of this involve specific inhibitors of Staphylococcus aureus isoleucyl-transfer-RNA synthetase 1 (IleRS1) and, more recently, Streptococcus pneumoniae methionyl-tRNA synthetase 1 (MetRS1). In both cases, resistance is due to the presence of a second gene that encodes another synthetase (IleRS2 or MetRS2). Here, we show that both S. pneumoniae MetRS2 and S. aureus IleRS2 have closely related homologues in the Gram-positive bacterium Bacillus anthracis, the causative agent of anthrax. Furthermore, similar to drug-resistant pathogens, strains of B. anthracis and its closest relative, B. cereus, also have wild-type ileS1 and metS1 genes. Clostridium perfringens, the causative agent of gangrene, also has two metS genes, whereas Oceanobacillus iheyensis isolated from deep-sea sediments has a single ileS2-type gene. This study shows the importance of understanding complex evolutionary networks of ancient horizontal gene transfer for the development of novel antibiotics.
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Affiliation(s)
- James R. Brown
- Bioinformatics Division, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
- Tel: +1 610 917 6374; Fax: +1 610 917 7901;
| | - Daniel Gentry
- Microbial Genetics Department, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
| | - Julie A. Becker
- Bioinformatics Division, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
| | - Karen Ingraham
- Microbial Genetics Department, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
| | - David J. Holmes
- Microbial Genetics Department, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
| | - Michael J. Stanhope
- Bioinformatics Division, GlaxoSmithKline, 1250 South Collegeville Road, UP1345, Collegeville, Pennsylvania 19426, USA
- Tel: +1 610 917 6577; Fax: +1 610 917 7901;
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