Factors affecting amino-acid-uptake by the ectomycorrhizal fungus Paxillus involutus
Författare
Summary, in English
Factors affecting amino acid uptake by the ectomycorrhizal fungus Paxillus involutus were investigated using tracer kinetic experiments. Amino acid uptake by P. involutus was dependent on the pH of the incubation medium. Uptake of L-glutamate and L-glutamine had a distinct pH optimum around pH 4.0 and declined sharply between pH 4.5 and 6.4. Uptake of alanine and aspartate was also highest at low pH values (3-4) but declined more slowly with increasing pH. Total uptake of labelled amino acids was unaffected by 0.05 or 0.5 mM ammonium while 5 mM ammonium decreased amino acid uptake. Nitrate or glucose did not significantly affect amino acid uptake but glucose greatly increased the proportion of carbon that was respired. Uptake of the different amino acids decreased by a factor of 4 to 10 with increasing age (1-5 wk) and the proportion of absorbed C-14 that was respired increased with age. Changes in the size of the total amino acid pool were inversely related to those in the rate of uptake and the pool increased steadily with age. The implications of the ability of P. involutus to take up amino acids are discussed.
Avdelning/ar
Publiceringsår
1995
Språk
Engelska
Sidor
1131-1138
Publikation/Tidskrift/Serie
Mycological Research
Volym
99
Issue
9
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Cambridge University Press
Ämne
- Biological Sciences
Nyckelord
- Aminoacid
- Metabolism
- Absorption
- Respiration
- pH
- Glucose
- Ammonium
- Mycorrhiza
- Symbionte
- Ectomycorrhiza
- Basidiomycetes
- Fungi
- Thallophyta
Status
Published
Forskningsgrupp
- Microbial Ecology
ISBN/ISSN/Övrigt
- ISSN: 0953-7562