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Tuntevski K, Durney BC, Snyder AK, LaSala PR, Nayak AP, Green BJ, Beezhold DH, Rio RVM, Holland LA, Lukomski S. Correction for Tuntevski et al., " Aspergillus Collagen-Like Genes ( acl): Identification, Sequence Polymorphism, and Assessment for PCR-Based Pathogen Detection". Appl Environ Microbiol 2024; 90:e0190123. [PMID: 38193682 PMCID: PMC10883766 DOI: 10.1128/aem.01901-23] [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] [Received: 10/30/2023] [Accepted: 11/09/2023] [Indexed: 01/10/2024] Open
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Spencer N, Santee M, Wetherhold A, Rio RVM. Draft genome sequence of Wigglesworthia glossinidia "palpalis gambiensis" isolate. Microbiol Resour Announc 2024; 13:e0091223. [PMID: 38206026 PMCID: PMC10868223 DOI: 10.1128/mra.00912-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 12/10/2023] [Indexed: 01/12/2024] Open
Abstract
The 0.719 Mb genome of the tsetse endosymbiont, Wigglesworthia glossinidia, from Glossina palpalis gambiensis is presented. This Wigglesworthia genome retains 611 protein-coding sequences and a 25.3% GC content. A cryptic plasmid is conserved, between Wigglesworthia isolates, suggesting functional significance. This genome adds a further dimension to characterize Wigglesworthia lineage-based differences.
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Affiliation(s)
- Noah Spencer
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, West Virginia, USA
- Biodesign Center for Mechanisms of Evolution and School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Mathilda Santee
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Adam Wetherhold
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Rita V. M. Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, West Virginia, USA
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3
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Lee MH, Hu G, Rio RVM. Symbiosis preservation: Putative regulation of fatty acyl-CoA reductase by miR-31a within the symbiont harboring bacteriome through tsetse evolution. Front Microbiol 2023; 14:1151319. [PMID: 37113220 PMCID: PMC10126493 DOI: 10.3389/fmicb.2023.1151319] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/21/2023] [Indexed: 04/29/2023] Open
Abstract
Tsetse flies are the sole vectors of African trypanosomes. In addition to trypanosomes, tsetse harbor obligate Wigglesworthia glossinidia bacteria that are essential to tsetse biology. The absence of Wigglesworthia results in fly sterility, thus offering promise for population control strategies. Here, microRNA (miRNAs) and mRNA expression are characterized and compared between the exclusive Wigglesworthia-containing bacteriome and adjacent aposymbiotic tissue in females of two evolutionarily distant tsetse species (Glossina brevipalpis and G. morsitans). A total of 193 miRNAs were expressed in either species, with 188 of these expressed in both species, 166 of these were novel to Glossinidae, and 41 miRNAs exhibited comparable expression levels between species. Within bacteriomes, 83 homologous mRNAs demonstrated differential expression between G. morsitans aposymbiotic and bacteriome tissues, with 21 of these having conserved interspecific expression. A large proportion of these differentially expressed genes are involved in amino acid metabolism and transport, symbolizing the essential nutritional role of the symbiosis. Further bioinformatic analyses identified a sole conserved miRNA::mRNA interaction (miR-31a::fatty acyl-CoA reductase) within bacteriomes likely catalyzing the reduction of fatty acids to alcohols which comprise components of esters and lipids involved in structural maintenance. The Glossina fatty acyl-CoA reductase gene family is characterized here through phylogenetic analyses to further understand its evolutionary diversification and the functional roles of members. Further research to characterize the nature of the miR-31a::fatty acyl-CoA reductase interaction may find novel contributions to the symbiosis to be exploited for vector control.
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Affiliation(s)
- Mason H. Lee
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States
| | - Gangqing Hu
- Department of Microbiology, Immunology, and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Rita V. M. Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States
- *Correspondence: Rita V. M. Rio,
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Weiss BL, Rio RVM, Aksoy S. Microbe Profile: Wigglesworthia glossinidia: the tsetse fly's significant other. Microbiology (Reading) 2022; 168:001242. [PMID: 36129743 PMCID: PMC10723186 DOI: 10.1099/mic.0.001242] [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] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/28/2022] [Indexed: 11/18/2022]
Abstract
Wigglesworthia glossinidia is an obligate, maternally transmitted endosymbiont of tsetse flies. The ancient association between these two organisms accounts for many of their unique physiological adaptations. Similar to other obligate mutualists, Wigglesworthia's genome is dramatically reduced in size, yet it has retained the capacity to produce many B-vitamins that are found at inadequate quantities in the fly's vertebrate blood-specific diet. These Wigglesworthia-derived B-vitamins play essential nutritional roles to maintain tsetse's physiological homeostasis as well as that of other members of the fly's microbiota. In addition to its nutritional role, Wigglesworthia contributes towards the development of tsetse's immune system during the larval period. Tsetse produce amidases that degrade symbiotic peptidoglycans and prevent activation of antimicrobial responses that can damage Wigglesworthia. These amidases in turn exhibit antiparasitic activity and decrease tsetse's ability to be colonized with parasitic trypanosomes, which reduce host fitness. Thus, the Wigglesworthia symbiosis represents a fine-tuned association in which both partners actively contribute towards achieving optimal fitness outcomes.
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Affiliation(s)
- Brian L. Weiss
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Rita V. M. Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, USA
| | - Serap Aksoy
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
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Lee MH, Medina Munoz M, Rio RVM. The Tsetse Metabolic Gambit: Living on Blood by Relying on Symbionts Demands Synchronization. Front Microbiol 2022; 13:905826. [PMID: 35756042 PMCID: PMC9218860 DOI: 10.3389/fmicb.2022.905826] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Tsetse flies have socioeconomic significance as the obligate vector of multiple Trypanosoma parasites, the causative agents of Human and Animal African Trypanosomiases. Like many animals subsisting on a limited diet, microbial symbiosis is key to supplementing nutrient deficiencies necessary for metabolic, reproductive, and immune functions. Extensive studies on the microbiota in parallel to tsetse biology have unraveled the many dependencies partners have for one another. But far less is known mechanistically on how products are swapped between partners and how these metabolic exchanges are regulated, especially to address changing physiological needs. More specifically, how do metabolites contributed by one partner get to the right place at the right time and in the right amounts to the other partner? Epigenetics is the study of molecules and mechanisms that regulate the inheritance, gene activity and expression of traits that are not due to DNA sequence alone. The roles that epigenetics provide as a mechanistic link between host phenotype, metabolism and microbiota (both in composition and activity) is relatively unknown and represents a frontier of exploration. Here, we take a closer look at blood feeding insects with emphasis on the tsetse fly, to specifically propose roles for microRNAs (miRNA) and DNA methylation, in maintaining insect-microbiota functional homeostasis. We provide empirical details to addressing these hypotheses and advancing these studies. Deciphering how microbiota and host activity are harmonized may foster multiple applications toward manipulating host health, including identifying novel targets for innovative vector control strategies to counter insidious pests such as tsetse.
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Affiliation(s)
- Mason H Lee
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States
| | - Miguel Medina Munoz
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States.,Department of Bacteriology, College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI, United States
| | - Rita V M Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States
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Medina Munoz M, Brenner C, Richmond D, Spencer N, Rio RVM. The holobiont transcriptome of teneral tsetse fly species of varying vector competence. BMC Genomics 2021; 22:400. [PMID: 34058984 PMCID: PMC8166097 DOI: 10.1186/s12864-021-07729-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 11/29/2020] [Accepted: 05/21/2021] [Indexed: 12/13/2022] Open
Abstract
Background Tsetse flies are the obligate vectors of African trypanosomes, which cause Human and Animal African Trypanosomiasis. Teneral flies (newly eclosed adults) are especially susceptible to parasite establishment and development, yet our understanding of why remains fragmentary. The tsetse gut microbiome is dominated by two Gammaproteobacteria, an essential and ancient mutualist Wigglesworthia glossinidia and a commensal Sodalis glossinidius. Here, we characterize and compare the metatranscriptome of teneral Glossina morsitans to that of G. brevipalpis and describe unique immunological, physiological, and metabolic landscapes that may impact vector competence differences between these two species. Results An active expression profile was observed for Wigglesworthia immediately following host adult metamorphosis. Specifically, ‘translation, ribosomal structure and biogenesis’ followed by ‘coenzyme transport and metabolism’ were the most enriched clusters of orthologous genes (COGs), highlighting the importance of nutrient transport and metabolism even following host species diversification. Despite the significantly smaller Wigglesworthia genome more differentially expressed genes (DEGs) were identified between interspecific isolates (n = 326, ~ 55% of protein coding genes) than between the corresponding Sodalis isolates (n = 235, ~ 5% of protein coding genes) likely reflecting distinctions in host co-evolution and adaptation. DEGs between Sodalis isolates included genes involved in chitin degradation that may contribute towards trypanosome susceptibility by compromising the immunological protection provided by the peritrophic matrix. Lastly, G. brevipalpis tenerals demonstrate a more immunologically robust background with significant upregulation of IMD and melanization pathways. Conclusions These transcriptomic differences may collectively contribute to vector competence differences between tsetse species and offers translational relevance towards the design of novel vector control strategies. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07729-5.
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Affiliation(s)
- Miguel Medina Munoz
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, 26505, USA
| | - Caitlyn Brenner
- Department of Biology, Washington and Jefferson College, Washington, PA, 15301, USA
| | - Dylan Richmond
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, 26505, USA
| | - Noah Spencer
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, 26505, USA
| | - Rita V M Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, 26505, USA.
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Medina Munoz M, Spencer N, Enomoto S, Dale C, Rio RVM. Quorum sensing sets the stage for the establishment and vertical transmission of Sodalis praecaptivus in tsetse flies. PLoS Genet 2020; 16:e1008992. [PMID: 32797092 PMCID: PMC7449468 DOI: 10.1371/journal.pgen.1008992] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 04/24/2020] [Revised: 08/26/2020] [Accepted: 07/14/2020] [Indexed: 12/19/2022] Open
Abstract
Bacterial virulence factors facilitate host colonization and set the stage for the evolution of parasitic and mutualistic interactions. The Sodalis-allied clade of bacteria exhibit striking diversity in the range of both plant and animal feeding insects they inhabit, suggesting the appropriation of universal molecular mechanisms that facilitate establishment. Here, we report on the infection of the tsetse fly by free-living Sodalis praecaptivus, a close relative of many Sodalis-allied symbionts. Key genes involved in quorum sensing, including the homoserine lactone synthase (ypeI) and response regulators (yenR and ypeR) are integral for the benign colonization of S. praecaptivus. Mutants lacking ypeI, yenR and ypeR compromised tsetse survival as a consequence of their inability to repress virulence. Genes under quorum sensing, including homologs of the binary insecticidal toxin PirAB and a putative symbiosis-promoting factor CpmAJ, demonstrated negative and positive impacts, respectively, on tsetse survival. Taken together with results obtained from experiments involving weevils, this work shows that quorum sensing virulence suppression plays an integral role in facilitating the establishment of Sodalis-allied symbionts in diverse insect hosts. This knowledge contributes to the understanding of the early evolutionary steps involved in the formation of insect-bacterial symbiosis. Further, despite having no established history of interaction with tsetse, S. praecaptivus can infect reproductive tissues, enabling vertical transmission through adenotrophic viviparity within a single host generation. This creates an option for the use of S. praecaptivus in the biocontrol of insect disease vectors via paratransgenesis.
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Affiliation(s)
- Miguel Medina Munoz
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States of America
| | - Noah Spencer
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States of America
| | - Shinichiro Enomoto
- Department of Biology, University of Utah, Salt Lake City, UT, United States of America
| | - Colin Dale
- Department of Biology, University of Utah, Salt Lake City, UT, United States of America
| | - Rita V. M. Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, Morgantown, WV, United States of America
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Macias AM, Marek PE, Morrissey EM, Brewer MS, Short DP, Stauder CM, Wickert KL, Berger MC, Metheny AM, Stajich JE, Boyce G, Rio RVM, Panaccione DG, Wong V, Jones TH, Kasson MT. Diversity and function of fungi associated with the fungivorous millipede, Brachycybe lecontii. FUNGAL ECOL 2019; 41:187-197. [PMID: 31871487 PMCID: PMC6927558 DOI: 10.1016/j.funeco.2019.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Fungivorous millipedes (subterclass Colobognatha) likely represent some of the earliest known mycophagous terrestrial arthropods, yet their fungal partners remain elusive. Here we describe relationships between fungi and the fungivorous millipede, Brachycybe lecontii. Their fungal community is surprisingly diverse, including 176 genera, 39 orders, four phyla, and several undescribed species. Of particular interest are twelve genera conserved across wood substrates and millipede clades that comprise the core fungal community of B. lecontii. Wood decay fungi, long speculated to serve as the primary food source for Brachycybe species, were absent from this core assemblage and proved lethal to millipedes in pathogenicity assays while entomopathogenic Hypocreales were more common in the core but had little effect on millipede health. This study represents the first survey of fungal communities associated with any colobognath millipede, and these results offer a glimpse into the complexity of millipede fungal communities.
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Affiliation(s)
- Angie M. Macias
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Paul E. Marek
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Ember M. Morrissey
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Michael S. Brewer
- Department of Biology, East Carolina University, Greenville, NC 27858, USA
| | | | - Cameron M. Stauder
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Kristen L. Wickert
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Matthew C. Berger
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Amy M. Metheny
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Jason E. Stajich
- Department of Microbiology and Plant Pathology and Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA
| | - Greg Boyce
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Rita V. M. Rio
- Department of Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Daniel G. Panaccione
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Victoria Wong
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Tappey H. Jones
- Department of Chemistry, Virginia Military Institute, Lexington, VA, 24450, USA
| | - Matt T. Kasson
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506, USA
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Abstract
Eukaryotic-bacterial symbioses are ubiquitous in nature. Pathogens and symbionts employ similar machinery, yet symbionts can minimize host damage. In this issue of Cell Host & Microbe, Enomoto et al. (2017) demonstrate how quorum sensing regulates expression of virulence genes at appropriate times, thereby enabling symbiont retention throughout the host lifespan.
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Affiliation(s)
- Rita V M Rio
- Department of Biology, Eberly College of Arts and Sciences, West Virginia University, 53 Campus Dr., Morgantown, WV 26506, USA.
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Ott BM, Rickards A, Gehrke L, Rio RVM. Characterization of shed medicinal leech mucus reveals a diverse microbiota. Front Microbiol 2015; 5:757. [PMID: 25620963 PMCID: PMC4288373 DOI: 10.3389/fmicb.2014.00757] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [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: 11/07/2014] [Accepted: 12/12/2014] [Indexed: 11/13/2022] Open
Abstract
Microbial transmission through mucosal-mediated mechanisms is widespread throughout the animal kingdom. One example of this occurs with Hirudo verbana, the medicinal leech, where host attraction to shed conspecific mucus facilitates horizontal transmission of a predominant gut symbiont, the Gammaproteobacterium Aeromonas veronii. However, whether this mucus may harbor other bacteria has not been examined. Here, we characterize the microbiota of shed leech mucus through Illumina deep sequencing of the V3-V4 hypervariable region of the 16S rRNA gene. Additionally, Restriction Fragment Length Polymorphism (RFLP) typing with subsequent Sanger Sequencing of a 16S rRNA gene clone library provided qualitative confirmation of the microbial composition. Phylogenetic analyses of full-length 16S rRNA sequences were performed to examine microbial taxonomic distribution. Analyses using both technologies indicate the dominance of the Bacteroidetes and Proteobacteria phyla within the mucus microbiota. We determined the presence of other previously described leech symbionts, in addition to a number of putative novel leech-associated bacteria. A second predominant gut symbiont, the Rikenella-like bacteria, was also identified within mucus and exhibited similar population dynamics to A. veronii, suggesting persistence in syntrophy beyond the gut. Interestingly, the most abundant bacterial genus belonged to Pedobacter, which includes members capable of producing heparinase, an enzyme that degrades the anticoagulant, heparin. Additionally, bacteria associated with denitrification and sulfate cycling were observed, indicating an abundance of these anions within mucus, likely originating from the leech excretory system. A diverse microbiota harbored within shed mucus has significant potential implications for the evolution of microbiomes, including opportunities for gene transfer and utility in host capture of a diverse group of symbionts.
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Affiliation(s)
- Brittany M Ott
- Department of Biology, West Virginia University Morgantown, WV, USA
| | - Allen Rickards
- Department of Biology, West Virginia University Morgantown, WV, USA
| | - Lauren Gehrke
- Department of Biology, West Virginia University Morgantown, WV, USA
| | - Rita V M Rio
- Department of Biology, West Virginia University Morgantown, WV, USA
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11
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Tuntevski K, Durney BC, Snyder AK, LaSala PR, Nayak AP, Green BJ, Beezhold DH, Rio RVM, Holland LA, Lukomski S. Aspergillus collagen-like genes (acl): identification, sequence polymorphism, and assessment for PCR-based pathogen detection. Appl Environ Microbiol 2013; 79:7882-95. [PMID: 24123732 PMCID: PMC3837832 DOI: 10.1128/aem.02835-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/02/2013] [Indexed: 12/16/2022] Open
Abstract
The genus Aspergillus is a burden to public health due to its ubiquitous presence in the environment, its production of allergens, and wide demographic susceptibility among cystic fibrosis, asthmatic, and immunosuppressed patients. Current methods of detection of Aspergillus colonization and infection rely on lengthy morphological characterization or nonstandardized serological assays that are restricted to identifying a fungal etiology. Collagen-like genes have been shown to exhibit species-specific conservation across the noncollagenous regions as well as strain-specific polymorphism in the collagen-like regions. Here we assess the conserved region of the Aspergillus collagen-like (acl) genes and explore the application of PCR amplicon size-based discrimination among the five most common etiologic species of the Aspergillus genus, including Aspergillus fumigatus, A. flavus, A. nidulans, A. niger, and A. terreus. Genetic polymorphism and phylogenetic analysis of the aclF1 gene were additionally examined among the available strains. Furthermore, the applicability of the PCR-based assay to identification of these five species in cultures derived from sputum and bronchoalveolar fluid from 19 clinical samples was explored. Application of capillary electrophoresis on nanogels was additionally demonstrated to improve the discrimination between Aspergillus species. Overall, this study demonstrated that Aspergillus acl genes could be used as PCR targets to discriminate between clinically relevant Aspergillus species. Future studies aim to utilize the detection of Aspergillus acl genes in PCR and microfluidic applications to determine the sensitivity and specificity for the identification of Aspergillus colonization and invasive aspergillosis in immunocompromised subjects.
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Affiliation(s)
| | | | | | - P. Rocco LaSala
- Department of Pathology, West Virginia University
- Clinical Laboratory, West Virginia University Healthcare, Morgantown, West Virginia, USA
| | - Ajay P. Nayak
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Morgantown, West Virginia, USA
| | - Brett J. Green
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Morgantown, West Virginia, USA
| | - Donald H. Beezhold
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Morgantown, West Virginia, USA
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12
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Snyder AK, Adkins KZ, Rio RVM. Use of the Internal Transcribed Spacer (ITS) Regions to Examine Symbiont Divergence and as a Diagnostic Tool for Sodalis-Related Bacteria. Insects 2011; 2:515-31. [PMID: 26467831 PMCID: PMC4553445 DOI: 10.3390/insects2040515] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [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] [Received: 09/21/2011] [Revised: 11/15/2011] [Accepted: 11/17/2011] [Indexed: 12/11/2022]
Abstract
Bacteria excel in most ecological niches, including insect symbioses. A cluster of bacterial symbionts, established within a broad range of insects, share high 16S rRNA similarities with the secondary symbiont of the tsetse fly (Diptera: Glossinidae), Sodalis glossinidius. Although 16S rRNA has proven informative towards characterization of this clade, the gene is insufficient for examining recent divergence due to selective constraints. Here, we assess the application of the internal transcribed spacer (ITS) regions, specifically the ITS(glu) and ITS(ala,ile), used in conjunction with 16S rRNA to enhance the phylogenetic resolution of Sodalis-allied bacteria. The 16S rRNA + ITS regions of Sodalis and allied bacteria demonstrated significant divergence and were robust towards phylogenetic resolution. A monophyletic clade of Sodalis isolates from tsetse species, distinct from other Enterobacteriaceae, was consistently observed suggesting diversification due to host adaptation. In contrast, the phylogenetic distribution of symbionts isolated from hippoboscid flies and various Hemiptera and Coleoptera were intertwined suggesting either horizontal transfer or a recent establishment from an environmental source. Lineage splitting of Sodalis-allied bacteria into symbiotic and free-living sister groups was also observed. Additionally, we propose an ITS region as a diagnostic marker for the identification of additional Sodalis-allied symbionts in the field. These results expand our knowledge of informative genome regions to assess genetic divergence since splitting from the last common ancestor, of this versatile insect symbiont clade that have become increasingly recognized as valuable towards our understanding of the evolution of symbiosis. These facultative and recently associated symbionts may provide a novel source of traits adaptable to the dynamic ecologies encountered by diverse host backgrounds.
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Affiliation(s)
- Anna K Snyder
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA.
| | - Kenneth Z Adkins
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA.
| | - Rita V M Rio
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA.
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Snyder AK, McMillen CM, Wallenhorst P, Rio RVM. The phylogeny of Sodalis-like symbionts as reconstructed using surface-encoding loci. FEMS Microbiol Lett 2011; 317:143-51. [PMID: 21251054 DOI: 10.1111/j.1574-6968.2011.02221.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Phylogenetic analyses of 16S rRNA support close relationships between the Gammaproteobacteria Sodalis glossinidius, a tsetse (Diptera: Glossinidae) symbiont, and bacteria infecting diverse insect orders. To further examine the evolutionary relationships of these Sodalis-like symbionts, phylogenetic trees were constructed for a subset of putative surface-encoding genes (i.e. ompA, spr, slyB, rcsF, ycfM, and ompC). The ompA and ompC loci were used toward examining the intra- and interspecific diversity of Sodalis within tsetse, respectively. Intraspecific analyses of ompA support elevated nonsynonymous (dN) polymorphism with an excess of singletons, indicating diversifying selection, specifically within the tsetse Glossina morsitans. Additionally, interspecific ompC comparisons between Sodalis and Escherichia coli demonstrate deviation from neutrality, with higher fixed dN observed at sites associated with extracellular loops. Surface-encoding genes varied in their phylogenetic resolution of Sodalis and related bacteria, suggesting conserved vs. host-specific roles. Moreover, Sodalis and its close relatives exhibit genetic divergence at the rcsF, ompA, and ompC loci, indicative of initial molecular divergence. The application of outer membrane genes as markers for further delineating the systematics of recently diverged bacteria is discussed. These results increase our understanding of insect symbiont evolution, while also identifying early genome alterations occurring upon integration of microorganisms with eukaryotic hosts.
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Affiliation(s)
- Anna K Snyder
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA
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Snyder AK, Deberry JW, Runyen-Janecky L, Rio RVM. Nutrient provisioning facilitates homeostasis between tsetse fly (Diptera: Glossinidae) symbionts. Proc Biol Sci 2010; 277:2389-97. [PMID: 20356887 PMCID: PMC2894912 DOI: 10.1098/rspb.2010.0364] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [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: 02/21/2010] [Accepted: 03/09/2010] [Indexed: 11/12/2022] Open
Abstract
Host-associated microbial interactions may involve genome complementation, driving-enhanced communal efficiency and stability. The tsetse fly (Diptera: Glossinidae), the obligate vector of African trypanosomes (Trypanosoma brucei subspp.), harbours two enteric Gammaproteobacteria symbionts: Wigglesworthia glossinidia and Sodalis glossinidius. Host coevolution has streamlined the Wigglesworthia genome to complement the exclusively sanguivorous tsetse lifestyle. Comparative genomics reveal that the Sodalis genome contains the majority of Wigglesworthia genes. This significant genomic overlap calls into question why tsetse maintains the coresidence of both symbionts and, furthermore, how symbiont homeostasis is maintained. One of the few distinctions between the Wigglesworthia and Sodalis genomes lies in thiamine biosynthesis. While Wigglesworthia can synthesize thiamine, Sodalis lacks this capability but retains a thiamine ABC transporter (tbpAthiPQ) believed to salvage thiamine. This genetic complementation may represent the early convergence of metabolic pathways that may act to retain Wigglesworthia and evade species antagonism. We show that thiamine monophosphate, the specific thiamine derivative putatively synthesized by Wigglesworthia, impacts Sodalis thiamine transporter expression, proliferation and intracellular localization. A greater understanding of tsetse symbiont interactions may generate alternative control strategies for this significant medical and agricultural pest, while also providing insight into the evolution of microbial associations within hosts.
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Affiliation(s)
- Anna K. Snyder
- Department of Biology, West Virginia University, 53 Campus Drive 5106 LSB, Morgantown, WV 26506, USA
| | - Jason W. Deberry
- Department of Biology, West Virginia University, 53 Campus Drive 5106 LSB, Morgantown, WV 26506, USA
| | | | - Rita V. M. Rio
- Department of Biology, West Virginia University, 53 Campus Drive 5106 LSB, Morgantown, WV 26506, USA
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Rio RVM, Maltz M, McCormick B, Reiss A, Graf J. Symbiont succession during embryonic development of the European medicinal leech, Hirudo verbana. Appl Environ Microbiol 2009; 75:6890-5. [PMID: 19648363 PMCID: PMC2772434 DOI: 10.1128/aem.01129-09] [Citation(s) in RCA: 21] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 07/28/2009] [Indexed: 11/20/2022] Open
Abstract
The European medicinal leech, Hirudo verbana, harbors simple microbial communities in the digestive tract and bladder. The colonization history, infection frequency, and growth dynamics of symbionts through host embryogenesis are described using diagnostic PCR and quantitative PCR. Symbiont species displayed diversity in temporal establishment and proliferation through leech development.
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Affiliation(s)
- Rita V M Rio
- West Virginia University, Department of Biology, 53 Campus Dr. 5106 LSB, Morgantown, WV 26506, USA.
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Hu C, Rio RVM, Medlock J, Haines LR, Nayduch D, Savage AF, Guz N, Attardo GM, Pearson TW, Galvani AP, Aksoy S. Infections with immunogenic trypanosomes reduce tsetse reproductive fitness: potential impact of different parasite strains on vector population structure. PLoS Negl Trop Dis 2008; 2:e192. [PMID: 18335067 PMCID: PMC2265429 DOI: 10.1371/journal.pntd.0000192] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [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: 07/16/2007] [Accepted: 01/17/2008] [Indexed: 11/18/2022] Open
Abstract
The parasite Trypanosoma brucei rhodesiense and its insect vector Glossina morsitans morsitans were used to evaluate the effect of parasite clearance (resistance) as well as the cost of midgut infections on tsetse host fitness. Tsetse flies are viviparous and have a low reproductive capacity, giving birth to only 6-8 progeny during their lifetime. Thus, small perturbations to their reproductive fitness can have a major impact on population densities. We measured the fecundity (number of larval progeny deposited) and mortality in parasite-resistant tsetse females and untreated controls and found no differences. There was, however, a typanosome-specific impact on midgut infections. Infections with an immunogenic parasite line that resulted in prolonged activation of the tsetse immune system delayed intrauterine larval development resulting in the production of fewer progeny over the fly's lifetime. In contrast, parasitism with a second line that failed to activate the immune system did not impose a fecundity cost. Coinfections favored the establishment of the immunogenic parasites in the midgut. We show that a decrease in the synthesis of Glossina Milk gland protein (GmmMgp), a major female accessory gland protein associated with larvagenesis, likely contributed to the reproductive lag observed in infected flies. Mathematical analysis of our empirical results indicated that infection with the immunogenic trypanosomes reduced tsetse fecundity by 30% relative to infections with the non-immunogenic strain. We estimate that a moderate infection prevalence of about 26% with immunogenic parasites has the potential to reduce tsetse populations. Potential repercussions for vector population growth, parasite-host coevolution, and disease prevalence are discussed.
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Affiliation(s)
- Changyun Hu
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Rita V. M. Rio
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Jan Medlock
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Lee R. Haines
- Department of Biochemistry and Microbiology, Petch Building, University of Victoria, Victoria, British Columbia, Canada
| | - Dana Nayduch
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Amy F. Savage
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Nurper Guz
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Geoffrey M. Attardo
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Terry W. Pearson
- Department of Biochemistry and Microbiology, Petch Building, University of Victoria, Victoria, British Columbia, Canada
| | - Alison P. Galvani
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Serap Aksoy
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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Rio RVM, Anderegg M, Graf J. Characterization of a catalase gene from Aeromonas veronii, the digestive-tract symbiont of the medicinal leech. Microbiology (Reading) 2007; 153:1897-1906. [PMID: 17526846 DOI: 10.1099/mic.0.2006/003020-0] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The catalase gene katA of the medicinal leech symbiont Aeromonas veronii bv. sobria was cloned, sequenced, and functionally characterized. Southern hybridization, using an A. veronii katA-specific hybridization probe, suggested the presence of a single gene copy in many Aeromonas species. A. veronii katA consisted of 1446 nt encoding a protein with a high degree of similarity to the small-subunit group III bacterial catalases. A catalase-null mutant (JG186) was constructed through gene-replacement mutagenesis. In the parent strain (HM21R), catalase activity was only detected in extracts of cells grown to early exponential phase following H(2)O(2) induction, in which the ability to induce activity was inversely related to optical density. In contrast, induced JG186 cells were very sensitive to oxidative stress, with survival being affected even at low H(2)O(2) concentrations. In contrast to the findings of previous reports of other symbiotic systems, the catalase mutant was not defective in its ability to competitively colonize or persist within its host, in both co-inoculation and sole-colonization assays. This body of evidence suggests either that oxidative stress, in the form of H(2)O(2) exposure, is not encountered by the microbial partner under the examined symbiotic conditions or that compensatory mechanisms exist. The data suggest that although many colonization factors reoccur, each symbiotic system has also evolved specific mechanisms that affect symbiont-host dynamics.
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Affiliation(s)
- Rita V M Rio
- Department of Molecular and Cell Biology, University of Connecticut, 91 N. Eagleville Road, Unit-3125, Storrs, CT 06269-3125, USA
| | - Matthias Anderegg
- Institute for Infectious Diseases, University of Berne, Friedbühlstr. 51, CH-3010 Berne, Switzerland
| | - Joerg Graf
- Institute for Infectious Diseases, University of Berne, Friedbühlstr. 51, CH-3010 Berne, Switzerland
- Department of Molecular and Cell Biology, University of Connecticut, 91 N. Eagleville Road, Unit-3125, Storrs, CT 06269-3125, USA
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Weiss BL, Mouchotte R, Rio RVM, Wu YN, Wu Z, Heddi A, Aksoy S. Interspecific transfer of bacterial endosymbionts between tsetse fly species: infection establishment and effect on host fitness. Appl Environ Microbiol 2006; 72:7013-21. [PMID: 16950907 PMCID: PMC1636136 DOI: 10.1128/aem.01507-06] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tsetse flies (Glossina spp.) can harbor up to three distinct species of endosymbiotic bacteria that exhibit unique modes of transmission and evolutionary histories with their host. Two mutualist enterics, Wigglesworthia and Sodalis, are transmitted maternally to tsetse flies' intrauterine larvae. The third symbiont, from the genus Wolbachia, parasitizes developing oocytes. In this study, we determined that Sodalis isolates from several tsetse fly species are virtually identical based on a phylogenetic analysis of their ftsZ gene sequences. Furthermore, restriction fragment-length polymorphism analysis revealed little variation in the genomes of Sodalis isolates from tsetse fly species within different subgenera (Glossina fuscipes fuscipes and Glossina morsitans morsitans). We also examined the impact on host fitness of transinfecting G. fuscipes fuscipes and G. morsitans morsitans flies with reciprocal Sodalis strains. Tsetse flies cleared of their native Sodalis symbionts were successfully repopulated with the Sodalis species isolated from a different tsetse fly species. These transinfected flies effectively transmitted the novel symbionts to their offspring and experienced no detrimental fitness effects compared to their wild-type counterparts, as measured by longevity and fecundity. Quantitative PCR analysis revealed that transinfected flies maintained their Sodalis populations at densities comparable to those in flies harboring native symbionts. Our ability to transinfect tsetse flies is indicative of Sodalis ' recent evolutionary history with its tsetse fly host and demonstrates that this procedure may be used as a means of streamlining future paratransgenesis experiments.
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Affiliation(s)
- Brian L Weiss
- Department of Epidemiology and Public Health, Yale University School of Medicine, LEPH 606, 60 College Street, New Haven, CT 06510, USA
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Graf J, Kikuchi Y, Rio RVM. Leeches and their microbiota: naturally simple symbiosis models. Trends Microbiol 2006; 14:365-71. [PMID: 16843660 DOI: 10.1016/j.tim.2006.06.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [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: 03/01/2006] [Revised: 06/09/2006] [Accepted: 06/20/2006] [Indexed: 10/24/2022]
Abstract
Strictly blood-feeding leeches and their limited microbiota provide natural and powerful model systems to examine symbiosis. Blood is devoid of essential nutrients and it is thought that symbiotic bacteria synthesize these for the host. In this review, three distinct leech-microbe associations are described: (i) the mycetome, which is the large symbiont-containing organ associated with the esophagus; (ii) the nephridia and bladders that form the excretory system; and (iii) the digestive tract, where two bacterial species dominate the microbiota. The current knowledge and features of leech biology that promote the investigation of interspecific interactions (host-microbe and microbe-microbe) and their evolution are highlighted.
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Affiliation(s)
- Joerg Graf
- Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06269-3125, USA.
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Abstract
Insect-borne diseases exact a high public health burden and have a devastating impact on livestock and agriculture. To date, control has proved to be exceedingly difficult. One such disease that has plagued sub-Saharan Africa is caused by the protozoan African trypanosomes (Trypanosoma species) and transmitted by tsetse flies (Diptera: Glossinidae). This presentation describes the biology of the tsetse fly and its interactions with trypanosomes as well as its symbionts. Tsetse can harbor up to three distinct microbial symbionts, including two enterics (Wigglesworthia glossinidia and Sodalis glossinidius) as well as facultative Wolbachia infections, which influence host physiology. Recent investigations into the genome of the obligate symbiont Wigglesworthia have revealed characteristics indicative of its long co-evolutionary history with the tsetse host species. Comparative analysis of the commensal-like Sodalis with free-living enterics provides examples of adaptations to the host environment (physiology and ecology), reflecting genomic tailoring events during the process of transitioning into a symbiotic lifestyle. From an applied perspective, the extensive knowledge accumulated on the genomic and developmental biology of the symbionts coupled with our ability to both express foreign genes in these microbes in vitro and repopulate tsetse midguts with these engineered microbes now provides a means to interfere with the host physiological traits which contribute to vector competence promising a novel tool for disease management.
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Affiliation(s)
- Serap Aksoy
- Department of Epidemiology and Public Health, Yale University School of Medicine, 60 College St., 606 LEPH, New Haven, CT 06510, USA.
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Abstract
Symbioses between eukaryotes and unicellular organisms are quite common, with examples copiously disseminated throughout the earth's biota. Arthropods, in particular, owe much of their ecological success to their microbial flora, which often provide supplements either lacking in the limited host diet or which the hosts are unable to synthesize. In addition to harboring beneficial microbes, many arthropods (vectors) also transmit pathogens to the animals and plants upon which they prey. Vector-borne diseases exact a high public health burden and additionally have a devastating impact on livestock and agriculture. Recent scientific discoveries have resulted in the development of powerful technologies for studying the vector's biology, to discover the weak links in disease transmission. One of the more challenging applications of these developments is transgenesis, which allows for insertion of foreign DNA into the insect's genome to modify its phenotype. In this review, we discuss an approach in which the naturally occurring commensal flora of insects are manipulated to express products that render their host environment inhospitable for pathogen transmission. Replacing susceptible insect genotypes with modified counterparts with reduced pathogen transmission ability, might provide a new set of armaments in the battle for vector-borne disease reduction.
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Affiliation(s)
- Rita V M Rio
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT 06510, USA
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Rio RVM, Lefevre C, Heddi A, Aksoy S. Comparative genomics of insect-symbiotic bacteria: influence of host environment on microbial genome composition. Appl Environ Microbiol 2004; 69:6825-32. [PMID: 14602646 PMCID: PMC262273 DOI: 10.1128/aem.69.11.6825-6832.2003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Commensal symbionts, thought to be intermediary amid obligate mutualists and facultative parasites, offer insight into forces driving the evolutionary transition into mutualism. Using macroarrays developed for a close relative, Escherichia coli, we utilized a heterologous array hybridization approach to infer the genomic compositions of a clade of bacteria that have recently established symbiotic associations: Sodalis glossinidius with the tsetse fly (Diptera, Glossina spp.) and Sitophilus oryzae primary endosymbiont (SOPE) with the rice weevil (Coleoptera, Sitophilus oryzae). Functional biologies within their hosts currently reflect different forms of symbiotic associations. Their hosts, members of distant insect taxa, occupy distinct ecological niches and have evolved to survive on restricted diets of blood for tsetse and cereal for the rice weevil. Comparison of genome contents between the two microbes indicates statistically significant differences in the retention of genes involved in carbon compound catabolism, energy metabolism, fatty acid metabolism, and transport. The greatest reductions have occurred in carbon catabolism, membrane proteins, and cell structure-related genes for Sodalis and in genes involved in cellular processes (i.e., adaptations towards cellular conditions) for SOPE. Modifications in metabolic pathways, in the form of functional losses complementing particularities in host physiology and ecology, may have occurred upon initial entry from a free-living to a symbiotic state. It is possible that these adaptations, streamlining genomes, act to make a free-living state no longer feasible for the harnessed microbe.
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Affiliation(s)
- Rita V M Rio
- Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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