title: Genetic analysis among environmental strains of Balamuthia mandrillaris recovered from an artificial lagoon and from soil in Sonora, Mexico.
abstract: Since the first report of Balamuthia mandrillaris as a causative agent of granulomatous amoebic encephalitis in humans, the environmental niche of this amoeba was assumed to be restricted to soil and dust. A single isolation from water was recently made independently by us from Northern Mexico. Now we report the isolation of 8 new strains of B. mandrillaris from Mexico. This continues the pattern of an excess of isolates from North America, compared to other parts of the world. All of the new isolates are environmental isolates, 7 from water samples and one from soil. The identity of each isolate was confirmed by PCR and by examining the sequences of the mitochondrial 16S-like rRNA gene. Success in amplification was determined using comparisons of amplifications of DNA from the strain CDC: V039 and the water strain (ITSON-BM1) as positive controls. The DNA sequences of the new isolates were compared to older strains from clinical cases using phylogenetic analysis, showing very high sequence similarity. The similarity among the new isolates and with previous clinical and environmental isolates of B. mandrillaris was also examined using biochemical and immunological studies. High homogeneity of total protein products, and similarity in antigenic moiety among the eight new isolates and two controls was found. Taken together, the molecular and biochemical studies indicate very low levels of genetic variation within B. mandrillaris.
authors: Programa de Doctorado en Ciencias en Biotecnología, Instituto Tecnológico de Sonora, Ciudad Obregón, Son., Mexico. Electronic address: luisfdolares@hotmail.com.
authors: Luis Fernando
authors: LF
authors: Lares-Jiménez
authors: Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA. Electronic address: booton.1@osu.edu.
authors: Gregory C
authors: GC
authors: Booton
authors: Programa de Doctorado en Ciencias en Biotecnología, Instituto Tecnológico de Sonora, Ciudad Obregón, Son., Mexico; Departamento de Ciencias Agronómicas y Veterinarias, Instituto Tecnológico de Sonora, Ciudad Obregón, Son., Mexico. Electronic address: fernando.lares@itson.edu.mx.
authors: Fernando
authors: F
authors: Lares-Villa
authors: Departamento del Área Químico Biológica, Universidad de Sonora, Hermosillo, Son., Mexico. Electronic address: velaz@guayacan.uson.mx.
authors: Carlos Arturo
authors: CA
authors: Velázquez-Contreras
authors: Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA; Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA. Electronic address: fuerst.1@osu.edu.
authors: Paul A
authors: PA
authors: Fuerst
mesh_terms: D059611:Balamuthia mandrillaris / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D015153:Blotting, Western; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D005618:Fresh Water / Q000469:parasitology*; D008800:Mexico; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000737:chemistry*; D017422:Sequence Analysis, DNA; D012987:Soil / Q000469:parasitology*
chemical_list: D003470:Culture Media; D015800:Protozoan Proteins; D012987:Soil
keywords: 16S-like rRNA gene; Balamuthia mandrillaris; Balamuthiasis; Diagnosis; Environmental distribution; Genotype