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Genotyping Encephalitozoon hellem isolates by analysis of the polar tube protein gene.

ABSTRACT: To develop an alternative genotyping tool, the genetic diversity of Encephalitozoon hellem was examined at the polar tube protein (PTP) locus. Nucleotide sequence analysis of the PTP gene divided 24 E. hellem isolates into four genotypes, compared to two genotypes identified by analysis of the internal transcribed spacer of the rRNA gene. The four PTP genotypes differed from each other by the copy number of the 60-bp central repeat as well as by point mutations. A simple PCR test was developed to differentiate E. hellem genotypes based on the difference in the size of PTP PCR products, which should facilitate the genotyping of E. hellem in clinical samples.

SUBMITTER: Xiao L

PROVIDER: S-EPMC88110 | biostudies-literature | 2001 Jun

REPOSITORIES: biostudies-literature

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Genotyping Encephalitozoon hellem isolates by analysis of the polar tube protein gene.

Xiao L L Li L L Moura H H Sulaiman I I Lal A A AA Gatti S S Scaglia M M Didier E S ES Visvesvara G S GS

Journal of clinical microbiology 20010601 6

To develop an alternative genotyping tool, the genetic diversity of Encephalitozoon hellem was examined at the polar tube protein (PTP) locus. Nucleotide sequence analysis of the PTP gene divided 24 E. hellem isolates into four genotypes, compared to two genotypes identified by analysis of the internal transcribed spacer of the rRNA gene. The four PTP genotypes differed from each other by the copy number of the 60-bp central repeat as well as by point mutations. A simple PCR test was developed t ...[more]

PMID: 11376056

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The molecular characterization of the major polar tube protein gene from Encephalitozoon hellem, a microsporidian parasite of humans.

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