Determination of enzyme-specific activities revealed that GLY1 encodes a threonine aldolase (TA) in Saccharomyces cerevisiae. A knock-out mutant auxotrophic for glycine lacked detectable activity. After transformation with YEp24GLY1 prototrophy was restored and TA-specific activity 16-fold higher than the wild type. Growth experiments using glucose as sole carbon source showed is more important biosynthesis SHM1 SHM2 encoding alternative serine hydroxymethyltransferases. On ethanol...

ABSTRACT Riboflavin production in the filamentous fungus Ashbya gossypii is limited by glycine, an early precursor required for purine synthesis. We report improvement of riboflavin this overexpression glycine biosynthetic enzyme threonine aldolase. The GLY1 gene encoding aldolase A. was isolated heterologous complementation glycine-auxotrophic Saccharomyces cerevisiae strain YM13 with a genomic library from . deduced amino acid sequence showed 88% similarity to S. In presence gene, 25 mU...

Riboflavin (vitamin B2), essential in tiny amounts as a precursor for oxidoreductase coenzymes, is yellow pigment. Although it causes cytotoxicity via photoinduced damage of macromolecules, several microorganisms are striking overproducers. A question, unanswered decades, whether riboflavin overproducers can benefit from this property. Here, we report an ultraviolet (UV) protective effect riboflavin. The spores Ashbya gossypii, riboflavin-overproducing fungus, more sensitive to UV than those...

During growth on glucose, Botrytis cinerea produced extracellular β-(1,3)(1,6)- d -glucan (cinerean), which formed an adhering capsule and slime. After glucose was exhausted from the medium, cinereanase activity increased <0.4 to 30 U/liter, effecting a striking loss in viscosity of culture. Cinerean cleaved into gentiobiose. Gentiobiose then hydrolyzed glucose. While strongest culture supernatant, gentiobiase located mainly cell wall fraction. The addition extra or cycloheximide...

Summary: Isocitrate lyase (ICL) was assayed during batch cultivations of Ashbya gossypii on soybean oil or glucose as carbon source. On oil, a correlation between enzyme activity and riboflavin synthesis observed. source, overproduction started in the late growth phase when exhausted. ICL appeared parallel reached maximum 0.41 U (mg protein) -1 . This suggested vitamin B 2 from intracellular reserve fat. specific correlated with concentration detected by antibodies. Itaconate, an efficient...

Riboflavin overproduction in the ascomycete Ashbya gossypii is limited by glycine, a precursor of purine biosynthesis, and therefore an indicator glycine metabolism. Disruption SHM2 gene, encoding serine hydroxymethyltransferase, resulted significant increase riboflavin productivity. Determination enzyme's specific activity revealed reduction from 3m-units/mg protein to 0.5m-unit/mg protein. The remaining was due isoenzyme encoded SHM1, which probably mitochondrial. A hypothesis proposed...

The isocitrate lyase‐encoding gene AgICL1 from the filamentous hemiascomycete Ashbya gossypii was isolated by heterologous complementation of a Saccharomyces cerevisiae icl1d mutant. open reading frame 1680 bp encoded protein 560 amino acids with calculated molecular weight 62 584. Disruption led to complete loss AgIcl1p activity and inability grow on oleic acid as sole carbon source. Compartmentation in peroxisomes demonstrated both Percoll density gradient centrifugation immunogold...

We describe the cloning, sequence and expression of gabA , encoding γ‐amino‐ n ‐butyrate (GABA) permease fungus Aspergillus nidulans . Sequence changes were determined for three up‐promoter ( gabI ) six loss‐of‐function mutations. The predicted protein contains 517 residues shows 30.3% overall identity with a putative GABA Arabidopsis thaliana 29.6% yeast choline transporter 23.4% UGA4 permease. Structural predictions favour 11–12 transmembrane domains. Comparison genomic cDNA sequences...

Ashbya gossypii can grow on triacyglycerol as carbon source. A degradation rate of 0.05 g x g-1 mycelial dry mass h-1 was detected for soybean oil. Although this within the sensitivity range lipase assays no activity detectable. On other hand, extracellular could be visualized by clearance halos round growing mycelium when trioleoylglycerol emulsified sole source in agar plates. Variation culture conditions revealed that reduced shaking speed and decreased fat content medium led to...

Summary: A specific isocitrate lyase (ICL) activity of 0.17 U (mg protein) −1 was detected in cultures the riboflavin-producing fungus Ashbya gossypii during growth on soybean oil. Enzyme not detectable glucose [<0.005 ], indicating a regulation. The enzyme purified 108-fold by means ammonium sulphate fractionation, gel filtration and cation-exchange chromatography. SDS-PAGE protein showed homogeneous band with an M r 66000. 254000 determined gel-filtration chromatography indicated...

The filamentous fungus Botrytis cinerea was found to produce four 1,3-β-glucanases (Glu I, II, III, IV). These enzymes were visualized by activity-staining after separation native polyacrylamide gel electrophoresis (PAGE). During growth on glucose as the single carbon source, only Glu III detectable in culture supernatant of B. cinerea. After exhausted from medium, extracellular (1,3)(1,6)-β-d-glucan (cinerean) capsule degraded. In this phase other three became and amount all increased....

Abstract Alanine : glyoxylate aminotransferase is one of three different enzymes used for glycine synthesis in Saccharomyces cerevisiae . The open reading frame YFL030w (named AGX1 the following), encoding this enzyme, was identified by comparing enzyme specific activities knockout strains. While 100% activity detectable parental strain, 2% found a YFL030w:: kanMX4 strain. ORF at that locus suspected to encode alanine because its predicted amino acid sequence showed 23% identity human...

The filamentous hemiascomycete Ashbya gossypii is a strong riboflavin overproducer. A striking but as yet uninvestigated phenomenon the fact that overproduction of this vitamin starts when growth rate declines, which means most produced in stationary phase, so-called production phase. specific activity 3,4-dihydroxy-2-butanone 4-phosphate (DHBP) synthase, first enzyme biosynthetic pathway for riboflavin, was determined during cultivation and an increase phase found. Furthermore, RIB3 mRNA,...

The conformation of cinerean, a microbial β-(1,3)(1,6)-d-glucan produced by the fungus Botrytis cinerea, was investigated in H2O, NaOH, and DMSO small-angle X-ray scattering (SAXS) neutron (SANS). native cinerean is wormlike chain with large persistence length. By treatment ultrasound rodlike fragments are formed. In aqueous solution has multihelical conformation. solutions NaOH multihelix disentangles into its single strands. These strands show structure factor random coil. With methods...