Spontaneous spatiotemporal organization in yeast extracts.

Stirred cytoplasmic extracts of the yeast Saccharomyces uvarum can, on addition of trehalose, display oscillations in the metabolite concentrations. Unstirred extracts may also develop spatiotemporal structures expressed in the metabolite concentrations. In this paper we present evidence of the existence of such patterns. The latter were recorded using the optical absorption of NADH in an annular cuvette, which was rotated in a photometer. Regularly spaced wavelike spatiotemporal standing waves were observed. At certain fixed points the NADH concentration appeared to remain constant. Such phenomena may improve our understanding of biochemical morphogenesis.