Morphological differences in crystals of multiple forms of yeast transketolase.

: Monocrystals of three individual multiple forms of yeast transketolase (A, B and C) differing in their thermostability have been obtained. Ammonium sulfate was used as a precipitating agent. Crystals of the mentioned forms were found to possess different morphology and stability during storage. Single crystals growing from the enzyme form C within 4-7 days were subsequently destroyed. Simultaneously, in the preparation, microcrystals started to grow in a great number. They were found to correspond morphologically to crystals obtained from transketolase A. A possibility of interconversions of the enzyme forms in sequence C----A----B is discussed.