Abstract
Acanthamoeba species are ubiquitous amoebae able to cause important infections in humans and other vertebrates. The full/near-full sequences (>2000 bp) of the small subunit ribosomal RNA gene (SSU rDNA or 18S rDNA) are used to cluster Acanthamoeba as genotypes, labeled T1 to T20. Genotype T15 remains an exception, being described only partially on a 1500-bp fragment. Strains are thus usually identified based on their 18S identity matches with reference strains, often using shorter (<500 bp) diagnostic fragments of the gene. Nevertheless, short fragments (<1000 bp) have been used to propose genotypes. This has been criticized, and doubts arise therefore on possible confusion leading to classify distinct partial sequences with a same label(s). We demonstrate herein that several partial sequences misassigned either to T16 or to T4, actually belong to at least two separate and distinct genotypes. We obtained the full 18S rDNA of a strain previously typed as T16 on the basis of a small fragment and demonstrated that it actually belongs to the recently described T19. We propose the name Acanthamoeba micheli sp. nov., for this strain. Furthermore, partial molecular phylogenies were performed to show that several other misassigned T16 partial sequences belong to a new genotype. This latter includes also misassigned T4 partial sequences, only recently available as full sequences and labeled as T20. We thus reassign these partial sequences to the genotype T20. Longer sequences, ideally at least 90 % of the total gene length, should be obtained from strains to ensure reliable diagnostic and phylogenetic results.
Similar content being viewed by others
References
Adamska M, Leonska-Duniec A, Lanocha N, Skotarczak B (2014) Thermophilic potentially pathogenic amoebae isolated from natural water bodies in Poland and their molecular characterization. Acta Parasitol 59:433–441
Alves JMP, Gusmão CX, Teixeira MM, Freitas D, Foronda AS, Affonso HT (2000) Random amplified polymorphic DNA profiles as a tool for the characterization of Brazilian keratitis isolates of the genus Acanthamoeba. Braz J Med Biol Res 33:19–26
Amann R, Springer R, Schönhuber W, Ludwig W, Schid EN, Müller KD, Michel R (1997) Obligate intracellular bacterial parasites of Acanthamoebae related to Chlamydia spp. Appl Environ Microbiol 63:115–121
Booton GC, Kelly DJ, Chu Y, Seal DV, Houang E, Lam DSC, Byers TJ, Fuerst PA (2002) 18S ribosomal DNA typing and tracking of Acanthamoeba species isolates from corneal scrape specimens, contact lenses, lens cases, and home water supplies of Acanthamoeba keratitis patients in Hong Kong. J Clin Microbiol 40:1621–1625
Callicott JH Jr, Nelson EC, Jones MM, dos Santos JG, Utz JP, Duma RJ, Morrison JV Jr (1968) Meningoencephalitis due to pathogenic free-living amoebae: report of two cases. JAMA 206:579–582
Carlesso AM, Mentz MB, da Machado ML, Carvalho A, Nunes TE, Maschio VJ, Rott MB (2014) Characterization of isolates of Acanthamoeba from the nasal mucosa and cutaneous lesions of dogs. Curr Microbiol 68:702–707
Corsaro D, Venditti D (2009) Detection of Chlamydiae from freshwater environments by PCR, amoeba coculture and mixed coculture. Res Microbiol 160:547–552
Corsaro D, Venditti D (2010) Phylogenetic evidence for a new genotype of Acanthamoeba (Amoebozoa, Acanthamoebida). Parasitol Res 107:233–238
Corsaro D, Venditti D (2011) More Acanthamoeba genotypes: limits to use rDNA fragments to describe new genotype. Acta Protozool 50:51–56
Corsaro D, Müller KD, Michel R (2013) Molecular characterization and ultrastructure of a new amoeba endoparasite belonging to the Stenotrophomonas maltophilia complex. Exp Parasitol 133:383–390
Dykova I, Lomm J, Schroeder-Diedrich JM, Booton GC, Byers TJ (1999) Acanthamoeba strains isolated from organs of freshwater fishes. J Parasitol 85:1106–1113
Fritsche TR, Gautom RK, Seyerdirshti S, Bergeron DL, Lindquist TD (1993) Occurrence of bacterial endosymbionts in Acanthamoeba spp. isolated from corneal and environmental specimens and contact lenses. J Clin Microbiol 31:1122–1126
Fuerst PA, Booton GC, Crary M (2015) Phylogenetic analysis and the evolution of the 18S rRNA gene typing system of Acanthamoeba. J Eukaryot Microbiol 62:69–84
Gast RJ (2001) Development of an Acanthamoeba-specific reverse dot-blot and the discovery of a new ribotype. J Eukaryot Microbiol 48:609–615
Gast RJ, Ledee DR, Fuerst PA, Byers TJ (1996) Subgenus systematics of Acanthamoeba: four nuclear 18S rDNA sequence types. J Eukaryot Microbiol 43:498–504
Geisen S, Fiore-Donno AM, Walochnik J, Bonkowski M (2014) Acanthamoeba everywhere: high diversity of Acanthamoeba in soils. Parasitol Res 113:3151–3158
Grün AL, Stemplewitz B, Scheid P (2014) First report of an Acanthamoeba genotype T13 isolate as etiological agent of a keratitis in humans. Parasitol Res 113:2395–2400
Hewett MK, Robinson BS, Monis PT, Saint CP (2003) Identification of a new Acanthamoeba 18S rRNA gene sequence type, corresponding to the species Acanthamoeba jacobsi Sawyer, Nerad and Visvesvara, 1992 (Lobosea: Acanthamoebidae). Acta Protozool 42:325–329
Horn M, Fritsche TR, Gautom RK, Schleifer KH, Wagner M (1999) Novel bacterial endosymbionts of Acanthamoeba spp. related to the Paramecium caudatum symbiont Caedibacter caryophilus. Environ Microbiol 1:357–367
Jobb G, von Haeseler A, Strimmer K (2004) TREEFINDER: a powerful graphical analysis environment for molecular phylogenetics. BMC Evol Biol 4:18
Kent M, Platt SR, Rech RR, Eagleson JS, Howerth EW, Shoff M, Fuerst PA, Booton G, Visvesvara GS, Schatzberg SJ (2011) Multisystemic infection with an Acanthamoeba sp in a dog. J Am Vet Med Assoc 238:1476–1481
Landell MF, Salton J, Caumo K, Broetto L, Rott MB (2013) Isolation and genotyping of free-living environmental isolates of Acanthamoeba spp. from bromeliads in Southern Brazil. Exp Parasitol 134:290–294
Łanocha N, Kosik-Bogacka D, Maciejewska A, Sawczuk M, Wilk A, Kuźna-Grygiel W (2009) The occurrence Acanthamoeba (free living amoeba) in environmental and respiratory samples in Poland. Acta Protozool 48:271–279
Magnet A, Henriques-Gil N, Galván-Diaz AL, Izquiedo F, Fenoy S, Del Aguila C (2014) Novel Acanthamoeba 18S rRNA gene sequence type from an environmental isolate. Parasitol Res 113:2845–2850
Marciano-Cabral F, Cabral G (2003) Acanthamoeba spp. as agents of disease in humans. Clin Microbiol Rev 16:273–307
Martinez AJ (1980) Is Acanthamoeba encephalitis an opportunistic infection? Neurology 30:567–574
Mortazavi PN, Goldsworthy G, Kirk R, Khan NA (2010) Acanthamoeba produces disseminated infection in locusts and traverses the locust blood–brain barrier to invade the central nervous system. BMC Microbiol 10:186
Nuprasert W, Putaporntip C, Pariyakanok L, Jongwutiwes S (2010) Identification of a novel T17 genotype of Acanthamoeba from environmental isolates and T10 genotype causing keratitis in Thailand. J Clin Microbiol 48:4636–4640
Otta DA, Rott MB, Carlesso AM, da Silva OS (2012) Prevalence of Acanthamoeba spp. (Sarcomastigophora: Acanthamoebidae) in wild populations of Aedes aegypti (Diptera: Culicidae). Parasitol Res 111:2017–2022
Page FC (1988) A new key to freshwater and soil Gymnamoebae. Freshwater Biological Association, Ambleside, pp 92–97
Pussard M, Pons R (1977) Morphologie de la paroi kystique et taxonomie du genre Acanthamoeba (Protozoa, Amoebida). Protistologica 8:557–598
Qvarnstrom Y, Nerad TA, Visvesvara GS (2013) Characterization of a new pathogenic Acanthamoeba species, A. byersi n. sp., isolated from a human with fatal amoebic encephalitis. J Eukaryot Microbiol 60:626–633
Risler A, Coupat-Goutaland B, Pélandakis M (2013) Genotyping and phylogenetic analysis of Acanthamoeba isolates associated with keratitis. Parasitol Res 112:3807–3816
Rivera WL, Adao DE (2009) 18S ribosomal DNA genotypes of Acanthamoeba species isolated from contact lens cases in the Philippines. Parasitol Res 105:1119–1124
Rott M, Caumo K, Sauter I, Eckert J, da Rosa L, da Silva O (2010) Susceptibility of Aedes aegypti (Diptera: Culicidae) to Acanthamoeba polyphaga (Sarcomastigophora: Acanthamoebidae). Parasitol Res 107:195–198
Schroeder JM, Booton GC, Hay J, Niszl IA, Seal DV, Markus MB, Fuerst PA, Byers TJ (2001) Use of subgenic 18S ribosomal DNA PCR and sequencing for genus and genotype identification of Acanthamoebae from humans with keratitis and from sewage sludge. J Clin Microbiol 39:1903–1911
Stothard DR, Schroeder-Diedrich JM, Awwad MH, Gast RJ, Ledee DR, Rodriguez-Zaragoza S, Dean CL, Fuerst PA, Byers TJ (1998) The evolutionary history of the genus Acanthamoeba and the identification of eight new 18S rRNA gene sequence types. J Eukaryot Microbiol 45:45–54
Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S (2011) MEGA5: Molecular Evolutionary Genetics Analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Mol Biol Evol 28:2731–2739
Tanveer T, Hameed A, Muazzam AG, Jung S-Y, Gul A, Matin A (2013) Isolation and molecular characterization of potentially pathogenic Acanthamoeba genotypes from diverse water resources including household drinking water from Khyber Pakhtunkhwa, Pakistan. Parasitol Res 112:2925–2932
Visvesvara GS, Booton GC, Kelley DJ, Fuerst P, Sriram R, Finkelstein A, Garner MM (2007) In vitro culture, serologic and molecular analysis of Acanthamoeba isolated from the liver of a keel-billed toucan (Ramphastos sulfuratus). Vet Parasitol 143:74–78
Walochnik J, Hassl A, Simon K, Benyr G, Aspök H (1999) Isolation and identification by partial sequencing of the 18S ribosomal gene of free-living amoebae from necrotic tissue of Basiliscus plumifrons (Sauria: Iguanidae). Parasitol Res 85:601–603
Walochnik J, Michel R, Aspöck H (2004) A molecular biological approach to the phylogenetic position of the genus Hyperamoeba. J Eukaryot Microbiol 51:433–440
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Supplementary Table 1
List of GenBank accession numbers of full and partial 18S rDNA sequences of Acanthamoeba used in this study. (XLS 26 kb)
Rights and permissions
About this article
Cite this article
Corsaro, D., Walochnik, J., Köhsler, M. et al. Acanthamoeba misidentification and multiple labels: redefining genotypes T16, T19, and T20 and proposal for Acanthamoeba micheli sp. nov. (genotype T19). Parasitol Res 114, 2481–2490 (2015). https://doi.org/10.1007/s00436-015-4445-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00436-015-4445-8