TY - JOUR
T1 - Transcriptional profiling of Gram-positive Arthrobacter in the phyllosphere: induction of pollutant degradation genes by natural plant phenolic compounds
AU - Scheublin, T.R.
AU - Deusch, S.
AU - Moreno-Forero, S.K.
AU - Müller, J.A.
AU - van der Meer, J.R.
AU - Leveau, J.H.J.
N1 - Reporting year: 2014
Metis note: 5560; ME
Data archiving: data archived at MDA
PY - 2014
Y1 - 2014
N2 - Arthrobacter chlorophenolicus A6 is a Gram-positive, 4-chlorophenol degrading soil bacterium that was recently shown to be an effective colonizer of plant leaf surfaces. The genetic basis for this phyllosphere competency is unknown. In this paper, we describe the genome-wide expression profile of A. chlorophenolicus on leaves of common bean (Phaseolus vulgaris) compared to growth on agar surfaces. In phyllosphere-grown cells, we found elevated expression of several genes known to contribute to epiphytic fitness, for example those involved in nutrient acquisition, attachment, stress response and horizontal gene transfer. A surprising result was the leaf-induced expression of a subset of the so-called cph genes for the degradation of 4-chlorophenol. This subset encodes the conversion of the phenolic compound hydroquinone to 3-oxoadipate, and was shown to be induced not only by 4-chlorophenol but also hydroquinone, its glycosylated derivative arbutin, and phenol. Small amounts of hydroquinone, but not arbutin or phenol, were detected in leaf surface washes of P. vulgaris by gas chromatography–mass spectrometry. Our findings illustrate the utility of genomics approaches for exploration and improved understanding of a microbial habitat. Also, they highlight the potential for phyllosphere-based priming of bacteria to stimulate pollutant degradation, which holds promise for the application of phylloremediation.
AB - Arthrobacter chlorophenolicus A6 is a Gram-positive, 4-chlorophenol degrading soil bacterium that was recently shown to be an effective colonizer of plant leaf surfaces. The genetic basis for this phyllosphere competency is unknown. In this paper, we describe the genome-wide expression profile of A. chlorophenolicus on leaves of common bean (Phaseolus vulgaris) compared to growth on agar surfaces. In phyllosphere-grown cells, we found elevated expression of several genes known to contribute to epiphytic fitness, for example those involved in nutrient acquisition, attachment, stress response and horizontal gene transfer. A surprising result was the leaf-induced expression of a subset of the so-called cph genes for the degradation of 4-chlorophenol. This subset encodes the conversion of the phenolic compound hydroquinone to 3-oxoadipate, and was shown to be induced not only by 4-chlorophenol but also hydroquinone, its glycosylated derivative arbutin, and phenol. Small amounts of hydroquinone, but not arbutin or phenol, were detected in leaf surface washes of P. vulgaris by gas chromatography–mass spectrometry. Our findings illustrate the utility of genomics approaches for exploration and improved understanding of a microbial habitat. Also, they highlight the potential for phyllosphere-based priming of bacteria to stimulate pollutant degradation, which holds promise for the application of phylloremediation.
KW - international
U2 - 10.1111/1462-2920.12375
DO - 10.1111/1462-2920.12375
M3 - Article
SN - 1462-2912
VL - 16
SP - 2212
EP - 2225
JO - Environmental Microbiology
JF - Environmental Microbiology
IS - 7
ER -