Spontaneous spatio-temporal organization in yeast cell suspension.

Under suitable conditions of substrate supply, cell suspensions of yeast Saccharomyces uvarum may display synchronized oscillations of glycolytic metabolism. Also in an unstirred suspension, spatial patterns can be induced by continuously feeding enzymically liberated glucose into the system. the absorption of NADH in the suspension was measured in an annular cuvette. The observed structures display moving waves, which travel over a distance of some centimetres in the cell suspension and seem to originate from a volume element in which the phase is ahead of those of its neighbours. The wavelength is estimated to be abot 10 cm and the velocity of spreading of the wave is about 5 cm/min. Waves are only observed in the beginning of glycolytic oscillations. Subsequently the spatial synchrony usually increases and destroys the previous organization. Similar spatio-temporal structures are observed during aggregation of the slime mould Dictyostelium discoideum and in the chemical reaction system of Belousov and Zhabotinsky.