Qualitative assessment of the facultative and aerobe gram negative bacteria of the intestinal microbiota of Crohn’s disease patients

• Grant number: 13/08767-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2013
• End date: December 31, 2013
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Josias Rodrigues
• Grantee: Luis Fernando do Vale Moraes
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Crohn's disease is a pathology characterized by the upsurge of lesions of varying severity which may affect the entire length of the intestinal tract, eventually leading to intestinal fistulas and/or obstruction. These manifestations are supported by an exacerbated immune response against antigens of the intestinal microbiota triggered by a defective immunologic system in these patients. Qualitative and quantitative changes seen in the species composition of the intestinal microbiota seem to be determinant for the symptoms observed. These changes comprise the reduction of the number of species (richness) associated with an intraspecific proliferation of a few groups (abundance). The latter are mainly represented by the proteobacteria, which are all Gram negative and one of most well-known prokaryotes. In this work, we intend to assess the biodiversity of the aerobe or facultative aerobe members of this group of bacteria present in different clinical materials of Crohn's disease patients. MacConkey broth cultures of 47 clinical samples (21 from 6 Crohn's disease and 26 from 8 control subjects) will be analyzed. The clinical materials comprise stools and mucosa biopsies of distinct intestinal sites. The biodiversity detected within the proteobaceria (gram negative) cultures will be confronted with that observed in the (total) fecal bacteria of each subject. The analysis will be based on the data of temperature gradient gel electrophoresis (TGGE) which detect genetic polymorphism, here comprising the V6 region of the 16SrDNA.