Food for microorganisms: Position-specific 13C labeling and 13C-PLFA analysis reveals preferences for sorbed or necromass C

- Free & sorbed 13C labeled Ala was applied to soil, incorporation in PLFA was measured.
- Most microorganisms can take up free & sorbed Ala equally; use basic metabolism.
- Fungi incorporated more sorbed C into PLFA; display traces of specialized metabolism.
- Incorporation in most PLFA decreased; actinomycetes incorporated increasing amounts.