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Microbe-dependent and nonspecific effects of procedures to eliminate the resident microbiota from Drosophila melanogaster.

ABSTRACT: Comparisons of animals bearing and lacking microorganisms can offer valuable insight into the interactions between animal hosts and their resident microbiota. Most hosts are naturally infected, and therefore, these comparisons require specific procedures (e.g., antibiotic treatment or physical exclusion of microorganisms) to disrupt the microbiota, but the potential for confounding nonspecific effects of the procedure on the traits of the host exists. Microbe-dependent and nonspecific effects can be discriminated by using multiple procedures: microbe-dependent effects are evident in hosts made microbe free by different procedures, but nonspecific effects are unique to individual procedures. As a demonstration, two procedures, oral administration of chlortetracycline (50 ?g ml(-1) diet) and microbiota removal by egg dechorionation, were applied to Drosophila melanogaster in a 2-by-2 factorial design. Microorganisms were undetectable in flies from dechorionated eggs and reduced by >99% in chlortetracycline-treated flies. Drosophila flies subjected to both protocols displayed an extended preadult development time, suggesting that the microbiota promotes the development rate. Female chlortetracycline-treated flies, whether from untreated or dechorionated eggs, displayed reduced protein content and egg fecundity, which could be attributed to the nonspecific effect of the antibiotic. We recommend that procedures used to disrupt the microbiota of animals should be selected, following systematic analysis of alternative mechanistically distinct procedures, on the basis of two criteria: those that achieve the greatest reduction (ideally, elimination) of the microbiota and those that achieve minimal nonspecific effects.

SUBMITTER: Ridley EV

PROVIDER: S-EPMC3685244 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Microbe-dependent and nonspecific effects of procedures to eliminate the resident microbiota from Drosophila melanogaster.

Ridley Emma V EV Wong Adam C N AC Douglas Angela E AE

Applied and environmental microbiology 20130308 10

Comparisons of animals bearing and lacking microorganisms can offer valuable insight into the interactions between animal hosts and their resident microbiota. Most hosts are naturally infected, and therefore, these comparisons require specific procedures (e.g., antibiotic treatment or physical exclusion of microorganisms) to disrupt the microbiota, but the potential for confounding nonspecific effects of the procedure on the traits of the host exists. Microbe-dependent and nonspecific effects ca ...[more]

PMID: 23475620

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Dataset Information

Microbe-dependent and nonspecific effects of procedures to eliminate the resident microbiota from Drosophila melanogaster.

Publications

Microbe-dependent and nonspecific effects of procedures to eliminate the resident microbiota from Drosophila melanogaster.

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