TY  - JOUR
A1  - Perkins, Anita
A1  - Rose, Andrew
A1  - Grossart, Hans-Peter
A1  - Rojas-Jimenez, Keilor Osvaldo
A1  - Barroso Prescott, Selva Kiri
A1  - Oakes, Joanne M.
T1  - Oxic and Anoxic Organic Polymer Degradation Potential of Endophytic Fungi From the Marine Macroalga, Ecklonia radiata
JF  - Frontiers in Microbiology
N2  - Cellulose and chitin are the most abundant polymeric, organic carbon source globally. Thus, microbes degrading these polymers significantly influence global carbon cycling and greenhouse gas production. Fungi are recognized as important for cellulose decomposition in terrestrial environments, but are far less studied in marine environments, where bacterial organic matter degradation pathways tend to receive more attention. In this study, we investigated the potential of fungi to degrade kelp detritus, which is a major source of cellulose in marine systems. Given that kelp detritus can be transported considerable distances in the marine environment, we were specifically interested in the capability of endophytic fungi, which are transported with detritus, to ultimately contribute to kelp detritus degradation. We isolated 10 species and two strains of endophytic fungi from the kelp Ecklonia radiata. We then used a dye decolorization assay to assess their ability to degrade organic polymers (lignin, cellulose, and hemicellulose) under both oxic and anoxic conditions and compared their degradation ability with common terrestrial fungi. Under oxic conditions, there was evidence that Ascomycota isolates produced cellulose-degrading extracellular enzymes (associated with manganese peroxidase and sulfur-containing lignin peroxidase), while Mucoromycota isolates appeared to produce both lignin and cellulose-degrading extracellular enzymes, and all Basidiomycota isolates produced lignin-degrading enzymes (associated with laccase and lignin peroxidase). Under anoxic conditions, only three kelp endophytes degraded cellulose. We concluded that kelp fungal endophytes can contribute to cellulose degradation in both oxic and anoxic environments. Thus, endophytic kelp fungi may play a significant role in marine carbon cycling via polymeric organic matter degradation.
KW  - kelp
KW  - fungi
KW  - endophytes
KW  - carbon cycling
KW  - extracellular enzymes
KW  - cellulose polymeric organic matter
Y1  - 2021
U6  - https://doi.org/10.3389/fmicb.2021.726138
SN  - 1664-302X
VL  - 12
SP  - 1
EP  - 13
PB  - Frontiers in microbiology
CY  - Lausanne, Schweiz
ER  - 
TY  - JOUR
A1  - Estendorfer, Jennifer
A1  - Stempfhuber, Barbara
A1  - Haury, Paula
A1  - Vestergaard, Gisle
A1  - Rillig, Matthias C.
A1  - Joshi, Jasmin Radha
A1  - Schröder, Peter
A1  - Schloter, Michael
T1  - The Influence of Land Use Intensity on the Plant-Associated Microbiome of Dactylis glomerata L.
JF  - Frontiers in plant science
N2  - In this study, we investigated the impact of different land use intensities (LUI) on the root-associated microbiome of Dactylis glomerata (orchardgrass). For this purpose, eight sampling sites with different land use intensity levels but comparable soil properties were selected in the southwest of Germany. Experimental plots covered land use levels from natural grassland up to intensively managed meadows. We used 16S rRNA gene based barcoding to assess the plant-associated community structure in the endosphere, rhizosphere and bulk soil of D. glomerata. Samples were taken at the reproductive stage of the plant in early summer. Our data indicated that roots harbor a distinct bacterial community, which clearly differed from the microbiome of the rhizosphere and bulk soil. Our results revealed Pseudomonadaceae, Enterobacteriaceae and Comamonadaceae as the most abundant endophytes independently of land use intensity. Rhizosphere and bulk soil were dominated also by Proteobacteria, but the most abundant families differed from those obtained from root samples. In the soil, the effect of land use intensity was more pronounced compared to root endophytes leading to a clearly distinct pattern of bacterial communities under different LUI from rhizosphere and bulk soil vs. endophytes. Overall, a change of community structure on the plant-soil interface was observed, as the number of shared OTUs between all three compartments investigated increased with decreasing land use intensity. Thus, our findings suggest a stronger interaction of the plant with its surrounding soil under low land use intensity. Furthermore, the amount and quality of available nitrogen was identified as a major driver for shifts in the microbiome structure in all compartments.
KW  - Dactylis glomerata
KW  - land use change
KW  - endophytes
KW  - rhizosphere
KW  - soil microbiome
KW  - biodiversity
Y1  - 2017
U6  - https://doi.org/10.3389/fpls.2017.00930
SN  - 1664-462X
VL  - 8
PB  - Frontiers Research Foundation
CY  - Lausanne
ER  -