TY  - JOUR
A1  - Wawra, Stephan
A1  - Fesel, Philipp
A1  - Widmer, Heidi
A1  - Timm, Malte
A1  - Seibel, Jürgen
A1  - Leson, Lisa
A1  - Kesseler, Leona
A1  - Nostadt, Robin
A1  - Hilbert, Magdalena
A1  - Langen, Gregor
A1  - Zuccaro, Alga
T1  - The fungal-specific beta-glucan-binding lectin FGB1 alters cell-wall composition and suppresses glucan-triggered immunity in plants
JF  - Nature Communications
N2  - β-glucans are well-known modulators of the immune system in mammals but little is known about β-glucan triggered immunity in planta. Here we show by isothermal titration calorimetry, circular dichroism spectroscopy and nuclear magnetic resonance spectroscopy that the FGB1 gene from the root endophyte Piriformospora indica encodes for a secreted fungal-specific β-glucan-binding lectin with dual function. This lectin has the potential to both alter fungal cell wall composition and properties, and to efficiently suppress β-glucan-triggered immunity in different plant hosts, such as Arabidopsis, barley and Nicotiana benthamiana. Our results hint at the existence of fungal effectors that deregulate innate sensing of β-glucan in plants.
KW  - Effectors in plant pathology
KW  - Fungal host response
KW  - Lectins
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165945
VL  - 7
ER  - 
TY  - JOUR
A1  - Homann, Arne
A1  - Timm, Malte
A1  - Seibel, Jürgen
T1  - Chemo-enzymatic synthesis and in vitro cytokine profiling of tailor-made oligofructosides
N2  - Background It is well known that carbohydrates play fundamental roles in cell signaling and infection processes as well as tumor formation and progression. However, the interaction pathways and cellular receptors targeted by carbohydrates and glycoconjugates remain poorly examined and understood. This lack of research stems, at least to a major part, from accessibility problems of large, branched oligosaccharides. Results To test glycan - cell interactions in vitro, a variety of tailored oligosaccharides was synthesized chemo-enzymatically. Glycosyltransferases from the GRAS organisms Bacillus megaterium (SacB) and Aspergillus niger (Suc1) were used in this study. Substrate engineering of these glycosyltransferases generally acting on sucrose leads to the controlled formation of novel tailored di-, tri- and tetrasaccharides. Already industrially used as prebiotics in functional food, the immunogenic potential of novel oligosaccharides was characterized in this study. A differential secretion of CXCL8 and CCL2 was observed upon oligosaccharide co-cultivation with colorectal epithelial Caco-2 cells. Conclusion Pure carbohydrates are able to stimulate a cytokine response in human endothelial cells in vitro. The type and amount of cytokine secretion depends on the type of co-cultivated oligosaccharide.
KW  - Chemie
KW  - Oligofructoside
KW  - Glycosyltransferase
KW  - Suc1
KW  - Aspergillus niger
KW  - SacB
KW  - Bacillus megaterium
KW  - CXCL8 (IL-8)
KW  - CCL2 (MCP-1)
KW  - Caco-2
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76393
ER  -