title: Botrytis cinerea can import and utilize nucleosides in salvage and catabolism and BcENT functions as high affinity nucleoside transporter.
abstract: Nucleotide de novo synthesis is an essential pathway in nearly all organisms. Transport processes as well as salvage and catabolism of nucleotides and pathway intermediates are required to balance nucleotide pools. We have analysed the genome of the fungal plant pathogen Botrytis cinerea for genes involved in nucleotide metabolism and found a complete set of genes necessary for purine and pyrimidine uptake and salvage based on homology of the gene products to corresponding proteins from Aspergillus nidulans. Candidate genes required for a complete purine catabolic sequence were identified in addition. These analyses were complemented by growth tests showing functional transport and salvage activity for pyrimidines. Growth of B. cinerea mycelium in nitrogen free medium could be restored by addition of purines, indicating the presence of a functional purine catabolism, whereas pyrimidines did not support growth. Bcin07g05490 (BcENT) was identified as sole member of the equilibrative nucleoside transporter (ENT) family. The protein synthesized in Saccharomyces cerevisiae revealed high affinity transport of adenosine (KM = 6.81 μM) and uridine (KM=9.04 μM). Furthermore, a BcENT knockout mutant was generated and tested in a range of growth and infection assays. These results provide detailed insight in the use of externally supplied nucleobases and nucleosides by B. cinerea.
authors: Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors: Manuel
authors: M
authors: Daumann
authors: Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors: Philippe
authors: P
authors: Golfier
authors: Phytopathologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors: Nathalie
authors: N
authors: Knüppel
authors: Phytopathologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
authors: Matthias
authors: M
authors: Hahn
authors: Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany. Electronic address: moehlmann@biologie.uni-kl.de.
authors: Torsten
authors: T
authors: Möhlmann
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics; D020171:Botrytis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003001:Cloning, Molecular; D019295:Computational Biology; D003470:Culture Media / Q000737:chemistry; D015870:Gene Expression; D055786:Gene Knockout Techniques; D016681:Genome, Fungal; D008660:Metabolism; D025282:Mycelium / Q000254:growth & development; D033703:Nucleoside Transport Proteins / Q000378:metabolism*; D009705:Nucleosides / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism
chemical_list: D003470:Culture Media; D033703:Nucleoside Transport Proteins; D009705:Nucleosides
keywords: Adenosine; ENT; Equilibrative nucleoside transporter; Purine; Uridine