Hybrid ribosome formation from Escherichia coli and chloroplast ribosome subunits

A 70S ribosome was prepared from a 30S ribosome subunit from Euglena gracilis chloroplasts and a 50S ribosome subunit from Escherichia coli. This hybrid ribosome was active in polyuridylic acid-directed polyphenylalanine synthesis.

Investigations on the Role of Boron in Plants III. Anatomical Observations

Electron microscopic examination of leaf mesophyll cells of boron-deficient sunflower plant reveals that chloroplasts degenerate and cell walls undergo profound structural changes before any visual deficiency symptoms become apparent. Mitochondria, which increase in number as deficiency develops, frequently show myeline figures, while nuclei may develop dense rhombohedral structures.