Effectiveness of Chromosomal and Plasmid-linked Genes for Enumerating Biotechnology Agents In Vivo

• Published in: Microbial ecology in health and disease 2002, Vol.14 (1), p.19-23
• Main Authors: George, S. Elizabeth, Nelson, Gail M.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biotechnology; Biotechnology Risk Assessment; Colonization In Vivo; Environment and pollution; Fundamental and applied biological sciences. Psychology; Genetically engineered organisms behavior (microorganisms, plants, animals); Industrial applications and implications. Economical aspects; Pseudomonas Aureofaciens
• ISSN: 0891-060X; 1651-2235; 1651-2235
• DOI: 10.1080/089106002760002711

Following the release of biotechnology agents, detection methods for monitoring human exposure to these microorganisms should be available. Enzymatic markers from chromosomal ( lacZY ) and plasmid ( xylE ) DNA were evaluated in an in vivo mouse model. Mice were treated orally or intranasally with Pseudomonas aureofaciens 3732RN-L11 (lacZY), 3732RN-L11::pRO1940 ( lacZY xylE ), or ATCC 13985. All strains were cleared within 5 days from the cecum or lungs. Direct plating, without intermediate antibiotic resistance selection, was used to detect the genetic markers. Chromosomal-linked lacZ was stable in vivo and in vitro but plasmid-linked xylE was not. Of the isolates recovered, 75% ( in vivo, oral), 98% ( in vivo, intranasal), and 16% ( in vitro ) remained XyIE +. Though more tedious to enumerate, both lacZY and xylE are plausible alternatives to antibiotic resistance markers for in vivo biotechnology risk assessment studies.