Species specificity of ribosomal proteins from chloroplast and cytoplasmic ribosomes of higher plants: Electrophoretic studies

Abstract

1. The proteins isolated by the LiCl-urea method from chloroplast ribosomes of several different plants are electrophoretically dissimilar from those extracted in a similar manner from the corresponding cytoplasmic ribosomes. 2. The electrophoretic patterns of proteins of cytoplasmic (80-S) ribosomes isolated from plants of different subclasses, different order, different genera, exhibit variable degrees of dissimilarity depending on the degree of taxonomic kinship of the plants from which the ribosomes were derived. The electrophoretic patterns of proteins extracted from plants of different varieties and species are identical. 3. The electrophoretic patterns of proteins isolated from the chloroplast (70-S) ribosomes of plants of different subclasses, of different order and of different genera exhibit a higher degree of electrophoretic dissimilarity than those of the corresponding 80-S ribosomes; i.e., in general in differently related plants the patterns obtained from cytoplasmic ribosomes tend to be more congruent than those of the 70-S ribosomes.