Radiorespirometry of Candida utilis in phased culture under nitrogen-, carbon-, and phosphorus-limited growth.
The release of 14CO2 from specifically labelled glucose ([G-1-14C],[G-2-14C],[G-3,4-14C], and [G-6-14C]) by phased cells of C. utilis was examined at intervals during 6-h cycles under conditions of N-,P-, and C-limited growth. On the basis that the release of 14CO2 from [G-1-C14] could serve as a measure of hexose monophosphate pathway (HMP) activity, of 14CO2 from [G-3,4-14C] as a measure of Embden-Meyerhof-Parnas (EMP) activity, and 14CO2 from [G-6-14C] as indicative of tricarboxylic acid (TCA) cycle activity, it was concluded that a relatively uniform operation of EMP occurred throughout the cycle in N-, P-, and C-limited cells, and of HMP and TCA in C-limited cells, but considerable variations took place in HMP and TCA cycle activities in N- and P-limited cells. The patterns of 14CO2 released from [G-2-14C] were more closely related to those observed from [G-1-14C] and [G-3,4-14C] than from [G-6-14C]. Changes in the rate of 14CO2 evolution during the cycle were sometimes abrupt and likely coincided with 'critical points' of metabolic activity in the cycle.
D002175:Candida / Q000254:growth & development / Q000378:metabolism*; D002244:Carbon / Q000494:pharmacology; D002245:Carbon Dioxide / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D002952:Citric Acid Cycle; D005947:Glucose / Q000378:metabolism; D006600:Hexosephosphates / Q000378:metabolism; D009584:Nitrogen / Q000494:pharmacology; D010758:Phosphorus / Q000494:pharmacology
D006600:Hexosephosphates; D002245:Carbon Dioxide; D010758:Phosphorus; D002244:Carbon; D005947:Glucose; D009584:Nitrogen