Quantifying Re-association of a Facultative Endohyphal Bacterium with a Filamentous Fungus

Part of the Methods in Molecular Biology book series (MIMB, volume 1848)


We present here a method to quantify reassociation between facultative endohyphal bacteria and filamentous fungal hosts. Our method takes advantage of the capabilities of fungal cell walls to selectively protect internal bacteria from gentamicin treatment, an assay adapted from studies of internalized bacterial pathogens in cell culture. We report the efficacy of gentamicin to kill planktonic bacteria treated during fungal coculture, and also describe and characterize a sampling scheme to recover and quantify culturable bacteria from the growing edge of fungal mycelium in vitro. This assay enables qualitative and quantitative tests of reassociation capabilities for facultative endohyphal bacteria with host fungi and provides a means to investigate the genetic basis for these associations in a repeatable way.

Key words

Endohyphal bacteria Endofungal bacteria Ascomycete Reassociation 



Financial support for this project was provided by the National Science Foundation (NSF IOS-1354219 to D. A. B., A. E. A., and Rachel E. Gallery). We thank Kayla Arendt, Sarah Araldi-Brondolo, Kevin Hockett, Rachel Gallery, and Justin Shaffer (University of Arizona) for helpful discussion and technical assistance.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Plant SciencesUniversity of ArizonaTucsonUSA
  2. 2.School of Animal and Comparative Biomedical SciencesUniversity of ArizonaTucsonUSA
  3. 3.Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonUSA

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