GATC-specific restriction and modification systems in treponemes.

M Piknova; P Pristas; P Javorsky; A Kasperowic; T Michalowski

doi:10.1111/j.1472-765x.2004.01483.x

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GATC-specific restriction and modification systems in treponemes.

M Piknova·P Pristas·P Javorsky·A Kasperowic·T Michalowski

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Abstract

AIMS: To investigate the presence of GATC-specific modification and restriction activities in rumen isolates of Treponema sp. METHODS: The presence of N6-methyladenine within GATC (Dam) sequences was analysed using isoschizomeric restriction endonucleases having different sensitivities to the methylation of the target sequence. A fast screening method was used for testing of site-specific endonuclease activities directly in crude cell extracts. Three out of six rumen isolates of Treponema sp. showed restriction activities. Restriction endonucleases were further purified by Heparin-Sepharose chromatography. Using PCR and specific primers, no sequence homologous to the T. pallidum dam gene was found. CONCLUSIONS: Three rumen treponemal strains were documented to possess MboI isoschizomeric restriction-modification systems. SIGNIFICANCE: This is the first report on restriction activity in rumen treponemes.

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Adenine Animals Base Sequence Chromatography, Affinity DNA Restriction-Modification Enzymes Deoxyribonucleases, Type II Site-Specific Polymerase Chain Reaction Rumen Sepharose Site-Specific DNA-Methyltransferase (Adenine-Specific)Substrate Specificity Treponema Journal Article Research Support, Non-U.S. Gov't

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M Piknova, P Pristas, P Javorsky, A Kasperowic, T Michalowski. 2004. GATC-specific restriction and modification systems in treponemes.. https://doi.org/10.1111/j.1472-765x.2004.01483.x

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