Isolation of Arthrobacter species from the phyllosphere and demonstration of their epiphytic fitness.

Tanja R Scheublin,Johan H J Leveau

doi:10.1002/mbo3.59

Tanja R Scheublin, Johan H J Leveau

Open Access

https://doi.org/10.1002/mbo3.59

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Journal: MicrobiologyOpen	Publication Date: Jan 28, 2013
Citations: 65	License type: CC BY 3.0

Affiliation: Netherlands Institute of Ecology

Abstract

Bacteria of the genus Arthrobacter are common inhabitants of the soil environment, but can also be recovered from leaf surfaces (the phyllosphere). Using enrichment cultures on 4-chlorophenol, we succeeded in specifically isolating Arthrobacter bacteria from ground cover vegetation in an apple orchard. Based on 16S rRNA gene sequencing, the isolates were found to belong to at least three different species of Arthrobacter. Compared to the model bacterial epiphyte Pantoea agglomerans, the Arthrobacter isolates performed as well or even better in a standardized laboratory test of phyllosphere fitness. A similar performance was observed with the well-characterized soil isolate Arthrobacter chlorophenolicus A6. These findings suggest that the frequently reported presence of Arthrobacter strains on plant foliage can be explained by the capacity to multiply and persist in the phyllosphere environment. As bacteria from the genus Arthrobacter are known for their ability to degrade a wide variety of organic pollutants, their high phyllosphere competency marks them as a promising group for future studies on phyllosphere-based bioremediation, for example, as foliar bioaugmentation on ground cover or buffer-zone vegetation to prevent pesticides from reaching soil, surface-, or groundwater.

Highlights

The phyllosphere (Ruinen 1961) is an open habitat that harbors large and diverse communities of bacteria, fungi, and other microorganisms (Leveau 2006)
We are interested in the drivers that underlie this presence, which evokes the basic question whether bacteria from the genus Arthrobacter constitute so-called residual or transient epiphytes (Whipps et al 2008)
We report here the targeted isolation of Arthrobacter strains from leaf surfaces by exploitation of the fact that Arthrobacter species can grow at the expense of aromatic pollutants including 4-chlorophenol (4-CP)

Summary

Introduction

The phyllosphere (Ruinen 1961) is an open habitat that harbors large and diverse communities of bacteria, fungi, and other microorganisms (Leveau 2006). We used 4-CP enrichment cultures to isolate Arthrobacter strains from plant leaves in an apple orchard and we confirmed their epiphytic fitness in laboratory tests.

Results

Conclusion