Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by GEORGE, S. E.
Right arrow Articles by CLAXTON, L. D.
Right arrow Search for Related Content
PubMed
Right arrow Articles by GEORGE, S. E.
Right arrow Articles by CLAXTON, L. D.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 1989 Oxford University Press

research-article

Effect of Ampicillin-lnduced Alterations in Murine Intestinal Microbiota on the Survival and Competition of Environmentally Released Pseudomonads

SUSAN E. GEORGE1,*, DEBRA B. WALSH{dagger}, ANDREW G. STEAD*,2 and LARRY D. CLAXTON*

*Health Effects Research Laboratory, U.S. Environmental Protection Agency Research Triangle Park, North Carolina 27711 {dagger}Environmental Health Research and Testing, Inc. P O. Box 12199, Research Triangle Park, North Carolina 27709

Received November 21, 1988; accepted May 11, 1989

The environmental release of genetically altered microorganisms has prompted the investigation of their potential health effects by the employment of other-than-human models. Although direct health effects are addressed, this investigation examines primarily some potential indirect health effects associated with environmentally released microorganisms. Indirect effects examined include colonization of the gastrointestinal tract, competition with the resident microbiota, and translo cation of the dosed microorganisms to other organs. Pseudomonads used in this study were isolated from a commercial product marketed for environmental PCB degradation. When mice were dosed by gavage with approximately 109 ampicillin-resistant pseudomonads, an increase in recovery from the intestinal tract, as compared to untreated animals, was observed 48 hr after dosing. Intestinal survival of Pseudomonas aeruginosa strain BC16 was enhanced 1000-fold and that of P maltophila strain BC6, 10-fold. Strains BC 17 and BC 18 were unaffected. Ampicillin treatment had a significant effect on the relative number of microbiota in the intestine, by selecting primarily for the facultative species. The lactose-fermenting enterobacteria, obligately anaerobic predominantly Gram-negative rods, and total aerobic and anaerobic populations were monitored in the presence and absence of the PCB-degrading pseudomonad. P. aeruginosa strain BC17 and P. maltophilia strain BC6 had a dose effect (p < 0.05) on the total aerobic and anaerobic populations as well as the lactose-fermenting enterobacteria. These results are similar to those for the mouse isolate control, strain PAMG. P. aeruginosa strain BC 18 had a dose effect (p < 0.05) on the total anaerobic population, including the obligately anaerobic Gram-negative bacilli. No translocation of the dosed strains to the liver, spleen, or lung was observed 48 hr after dosing.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.