TITLE:
Temperature Gradient Gel Electrophoresis as a Valuable Accessory Tool for Assessment of Dysbiosis in Crohn’s Disease
AUTHORS:
Vanessa Rafaela de Carvalho, Rogeria Keller, Ana Carolina da Silva Santos, Josias Rodrigues
KEYWORDS:
Dysbiosis, Proteobacteria, Escherichia coli, Crohn’s Disease
JOURNAL NAME:
Advances in Microbiology,
Vol.6 No.8,
July
20,
2016
ABSTRACT: Escherichia coli and other
Proteobacteria are augmented and several other bacteria are diminished in
Crohn’s (CD) disease patients’ intestine. This imbalance in bacterial species
composition—termed dysbiosis—seems to be determinant of CD
manifestation. Since a great part of intestinal bacteria are not cultivable, detection of CD dysbiosis is
accomplished by molecular tools, involving sequences analysis of the
16SrRNA gene (16SrDNA) present in the patient’s clinical samples, which can be
done by sequencing or electrophoresis in denaturing gels of 16SrDNA amplicons.
By analyzing, by temperature gradient gel
electrophoresis (TGGE) and next generation sequencing of 16SV6-V8rDNA amplicons
present in gram negative cultures from four distinct clinical samples of a
control subject and a CD patient, this study demonstrates that both techniques
were able to detect E. coli overgrowth
and reduction in species richness in CD and that TGGE can discriminate sequences
collectively labeled as “unclassified” in
16SrDNA databases. Although TGGE per se does not identify the sequences, the
discriminatory power that it confers represents valuable accessory information
to next generation DNA sequencing (NGS), and as such must be used as a NGS
complementary tool.