An efficient method for 15N-labeling of chitin in fungi.
To permit facile (15)N solid-state NMR (ssNMR) analysis of the degree of acetylation (DA) of chitinous materials in fungi a method for the introduction of a (15)N isotopic label has been developed. Using Penicillium chrysogenum as a model system, a series of (15)N-based media were surveyed for their abilities to support mycelial growth, and a rich medium supplemented with ((15)NH(4))(2)SO(4) supported good growth. Uptake of label into chitin extracted from mycelia grown in the rich ((15)NH(4))(2)SO(4)-based media was monitored by mass spectrometry, with approximately 1 g/L of ((15)NH(4))(2)SO(4) leading to approximately 65% incorporation. The labeled chitin was studied by ssNMR to determine its DA, and the (15)N label permitted measurement of DA to within 0.5% with acquisition times of on the order of half an hour. Similar studies validated the method for DA measurements on chitin from cultures of Aspergillus niger and Mucor rouxii.
Watson
Helen R
HR
Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, United Kingdom.
Apperley
David C
DC
Dixon
David P
DP
Edwards
Robert
R
Hodgson
David R W
DR
D000107:Acetylation; D001234:Aspergillus niger / Q000378:metabolism; D002686:Chitin / Q000737:chemistry* / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D009089:Mucor / Q000378:metabolism; D009587:Nitrogen Isotopes; D010408:Penicillium chrysogenum / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D009587:Nitrogen Isotopes; D002686:Chitin