[en] Soils are very rich environments where the diversity of microorganisms is very high. These microorganisms play an important role in the degradation of organic matter with enzymes able to degrade it. This work aims to discover, by functional screening, new microbial glycoside hydrolases from soils collected in winter and spring in a winter wheat crop. The genomic DNA was extracted from both soils to construct two libraries in Escherichia coli. These libraries were then screened for beta-glucosidase activities on 2YT agar media containing 0.5% esculin and 0.1% ammonium iron (III) citrate. At this time, about 250.000 clones from each library have been screened. Two beta-glucosidases have already been found in the winter library while five beta-glucosidases and two glycosyltransferases were identified in the spring library. Sequence analyses with the BLASTX program revealed putative enzymes showing between 25% and 72% sequence identity with known enzymes and belonging to three glycoside hydrolase families (GH1, GH3 and GH20) and to two probably new glycosyltransferase families. Biochemical characterisation of the candidates at several pH values and temperatures, and with four substrates, is in progress.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Stroobants, Aurore ; Université de Liège - ULiège > Chimie et bio-industries > Microbiologie et génomique
Portetelle, Daniel ; Université de Liège - ULiège > Chimie et bio-industries > Microbiologie et génomique
Vandenbol, Micheline ; Université de Liège - ULiège > Chimie et bio-industries > Microbiologie et génomique
Language :
English
Title :
Screening of two agricultural genomic DNA libraries to seek new glycoside hydrolases
Publication date :
07 February 2014
Event name :
19th National Symposium on Applied Biological Sciences