title: Direct Detection and Quantification of Bacterial Genes Associated with Inflammation in DNA Isolated from Stool.
abstract: Although predominantly associated with health benefits, the gut microbiota has also been shown to harbor genes that promote inflammation. In this work, we report a method for the direct detection and quantification of these pro-inflammatory bacterial genes by PCR and qPCR in DNA extracted from human stool samples. PCR reactions were performed to detect (i) thepksisland genes, (ii)tcpC, which is present in some strains ofEscherichia coliand (iii)gelEpresented in some strains ofEnterococcus faecalis. Additionally, we screened for the presence of the following genes encoding cyclomodulins that disrupted mammalian cell division: (iv)cdt(which encodes the cytolethal distending toxin) and (v)cnf-1 (which encodes the cytotoxic necrotizing factor-1). Our results show that 20% of the samples (N = 41) tested positive for detectable amounts ofpksisland genes, whereas 10% of individuals were positive fortcpCorgelEand only one individual was found to harbor thecnf-1 gene. Of the 13 individuals that were positive for at least one of the pro-inflammatory genes, 5 were found to harbor more than one. A quantitative version of the assay, which used real-time PCR, revealed the pro-inflammatory genes to be in high copy numbers: up to 1.3 million copies per mg of feces for thepksisland genes. Direct detection of specific genes in stool could prove useful toward screening for the presence of pro-inflammatory bacterial genes in individuals with inflammatory bowel diseases or colorectal cancer.
authors: Department of Biochemistry, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico ; Molecular Sciences Building, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico.
authors: Ramón
authors: R
authors: Gómez-Moreno
authors: Department of Microbiology and Medical Zoology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico.
authors: Iraida E
authors: IE
authors: Robledo
authors: Department of Biochemistry, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico ; Molecular Sciences Building, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico.
authors: Abel
authors: A
authors: Baerga-Ortiz
keywords: Gut Inflammation; Microbial Biomarkers; Microbiota; PCR; Stool Samples
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