Misguided phylogenetic comparisons using DGGE excised bands may contaminate public sequence databases
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Updated: Mar 22, 2026

Denaturing Gradient Gel Electrophoresis DGGE
Published on: February 25, 2007
Victor Satler Pylro1, Daniel Kumazawa Morais1, Karlos Henrique Martins Kalks2
1Genomics and Computational Biology Group, René Rachou Research Centre - CPqRR, Av. Augusto de Lima, 1715, 30190-002 Belo Horizonte, Minas Gerais, Brazil.
Abstract:
Controversy surrounding bacterial phylogenies has become one of the most important challenges for microbial ecology. Comparative analyses with nucleotide databases and phylogenetic reconstruction of the amplified 16S rRNA genes from DGGE (Denaturing Gradient Gel Electrophoresis) excised bands have been used by several researchers for the identification of organisms in complex samples. Here, we individually analyzed DGGE-excised 16S rRNA gene bands from 10 certified bacterial strains of different species, and demonstrated that this kind of approach can deliver erroneous outcomes to researchers, besides causing/emphasizing errors in public databases.
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