Characterizing the states of yeast cytoplasm using single particle tracking

The cytoplasmic states of yeast cytoplasm have been characterized using differential interference contrast microscopy and high resolution single particle tracking. Lipid granules naturally occurring in the yeast cytoplasm have been found to diffuse anomalously in the cytoplasm. Two distinct physiological states of yeast cytoplasm were identified with corresponding [Greek small letter alpha] values of [Greek small letter alpha] = 0.66 [plus or minus] 0.1 for the fast moving state and [Greek small letter alpha] = 0.43 [plus or minus] 0.04 for the slow moving state. The generalized diffusion constant D, was identified as a new indicator for cytoplasmic state classification, while a critical value of [Greek small letter alpha] = 0.485 [plus or minus] 0.005 was determined for state transition. Fast moving granules were established as a marker for optimally grown cells, while the origin of the slow moving state was linked to cells constrained to grow under sub-optimal cold conditions.