Regulation of Nigeran Accumulation by Aspergillus aculeatus
AUTOR(ES)
Gold, Michael H.
RESUMO
Nigeran (mycodextran), an unbranched glucan consisting of alternating α,1–4 and α,1–3 linkages, is accumulated intracellularly by Aspergillus aculeatus, under conditions of nitrogen limitation and low pH (optimum pH 5.0). Both conditions are necessary. Nigeran is synthesized de novo from exogenous glucose and accounts for about 20% of the glucose transported by the mycelium. The polymer is diluted out but not degraded when the mycelium is transferred to fresh medium containing NH4+. Cycloheximide prevents development of the nigeran biosynthetic system. The addition of substrate levels of NH4+ to nigeran-accumulating mycelium immediately suppresses further nigeran buildup, presumably by diverting glucose to the biosynthesis of amino acids, nucleotides, etc.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=285301Documentos Relacionados
- Intracellular Localization of Nigeran in the Wall of Aspergillus aculeatus by Autoradiography with the Electron Microscope
- Distribution and conformation of crystalline nigeran in hyphal walls of Aspergillus niger and Aspergillus awamori.
- Combined Molecular and Biochemical Approach Identifies Aspergillus japonicus and Aspergillus aculeatus as Two Species
- Assimilation of Cellooligosaccharides by a Cell Surface-Engineered Yeast Expressing β-Glucosidase and Carboxymethylcellulase from Aspergillus aculeatus
- Production and composition of an exocellular Nigeran-protein complex isolated from cultures of Aspergillus awamori.