Print Email Facebook Twitter Database mining and transcriptional analysis of genes encoding inulin-modifying enzymes of Aspergillus niger Title Database mining and transcriptional analysis of genes encoding inulin-modifying enzymes of Aspergillus niger Author Yuan, X.L. Goosen, C. Kools, H. van der Maarel, M.J.E.C. van den Hondel, C.A.M.J.J. Dijkhuizen, L. Ram, A.F.J. TNO Kwaliteit van Leven Publication year 2006 Abstract As a soil fungus, Aspergillus niger can metabolize a wide variety of carbon sources, employing sets of enzymes able to degrade plant-derived polysaccharides. In this study the genome sequence of A. niger strain CBS 513.88 was surveyed, to analyse the gene/enzyme network involved in utilization of the plant storage polymer inulin, and of sucrose, the substrate for inulin synthesis in plants. In addition to three known activities, encoded by the genes suc 1 (invertase activity; designated sucA), inuE (exo-inulinase activity) and inuAlinuB (endo-inulinase activity), two new putative invertase-like proteins were identified. These two putative proteins lack N-terminal signal sequences and therefore are expected to be intracellular enzymes. One of these two genes, designated sucB, is expressed at a low level, and its expression is up-regulated when A. niger is grown on sucrose- or inulin-containing media. Transcriptional analysis of the genes encoding the sucrose- (sucA) and inulin-hydrolysing enzymes (inuA and inuE) indicated that they are similarly regulated and all strongly induced on sucrose and inulin. Analysis of a ΔcreA mutant strain of A. niger revealed that expression of the extracellular inulinolytic enzymes is under control of the catabolite repressor CreA. Expression of the inulinolytic enzymes was not induced by fructose, not even in the ΔcreA background, indicating that fructose did not act as an inducer. Evidence is provided that sucrose, or a sucrose-derived intermediate, but not fructose, acts as an inducer for the expression of inulinolytic genes in A. niger. © 2006 SGM. Chemicals / CAS: glycosidase, 9032-92-2; inulin, 9005-80-5; sucrose, 122880-25-5, 57-50-1; DNA, Fungal; Fructose, 30237-26-4; Inulin, 9005-80-5; Protein Sorting Signals; RNA, Fungal; RNA, Messenger; Sucrose, 57-50-1; beta-Fructofuranosidase, 184.108.40.206. Molecular Sequence Numbers: GENBANK: BAA12321, BAA25684, BAA33797, BAA33798, BAB19132, BAB67771, BAC16218, BAD01476, CAA04131, CAA07345, CAA40488, CAA56684, CAA73208, CAB89083, CAC28747, CAC44220, EAA59102, EAA61090, EAA69589, EAA69879, EAA71892, EAA72735, EAA78236, EAK82399, EAK84508, EAL85540, EAL86248, EAL86253, EAL87222, P00724, S33920, XP_360436, XP_360455, XP_365805, XP_367933, XP_369679, DQ233218, DQ233219, DQ233220, DQ233221, DQ233222, DQ233223; Subject Food technologycell enzymefungal enzymeglycosidaseinulininulin modifying enzymesucroseunclassified drugarticleAspergillus nigercatabolite repressioncontrolled studyculture mediumenzyme activityfungal metabolismfungal strainfungus culturefungus growthgene sequencegenetic codegenetic transcriptiongenomegenome analysisinformation processingnonhumannucleotide sequencepriority journalprotein analysisprotein expressionsequence analysistranscription regulationupregulationAspergillus nigerbeta-FructofuranosidaseBlotting, NorthernComputational BiologyDNA, FungalFructoseGene Expression Regulation, FungalGenome, FungalInulinMolecular Sequence DataPhylogenyProtein Sorting SignalsRNA, FungalRNA, MessengerSequence Homology, Amino AcidSucroseTranscription, GeneticAspergillus nigerFungi To reference this document use: http://resolver.tudelft.nl/uuid:a7d5d339-837a-4156-8091-7b08e304bace DOI https://doi.org/10.1099/mic.0.29051-0 TNO identifier 239511 ISSN 1350-0872 Source Microbiology, 152 (10), 3061-3073 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.