Generation and maintenance of synchrony in Saccharomyces cerevisiae continuous culture [PROOF].
Murray DB, Klevecz RR, Lloyd D
Experimental Cell Research (2003)
Category: oscillations ¤ Added: May 27, 2003 ¤ Rating: ◊◊
UNCORRECTED PROOF Cultures of Saccharomyces cerevisiae grown continuously produce an autonomous oscillation in many metabolic outputs. The most conveniently measured variable, i.e., dissolved oxygen concentration, oscillates with a period of 40–55 min. Previously we have identified two compounds capable of resetting phase, acetaldehyde and hydrogen sulfide. The phase-response curves constructed for acetaldehyde show a strong (Type 0) response at 3.0 mM and a weak (Type 1) response at 1.0 mM. Ammonium sulfide phase-response curves (pulse injected at 1.0 M and 3.0 M) revealed that sulfide is only an effective perturbation agent when endogenous sulfide concentrations are at a maximum. Also only Type 1 phase responses were observed. When the phase-response curve for sulfide (at 3.0 M) was constructed, phase responses were at a maximum at 60°, indicating the possible involvement of sulfite in cell synchronization. It is concluded that endogenously produced acetaldehyde and sulfite tune the oscillation of mitochondrial energization state whereas sulfide mediates population synchrony.