Mutations Altering Chloroplast Ribosome Phenotype in Chlamydomonas, II. A New Mendelian Mutation

John E Boynton; Nicholas W Gillham; Barbara Burkholder

doi:10.1073/pnas.67.3.1505

. 1970 Nov;67(3):1505–1512. doi: 10.1073/pnas.67.3.1505

Mutations Altering Chloroplast Ribosome Phenotype in Chlamydomonas, II. A New Mendelian Mutation^{^*}

John E Boynton ^1,², Nicholas W Gillham ^1,², Barbara Burkholder ^1,²

PMCID: PMC283383 PMID: 16591885

Abstract

A new mutation of Chlamydomonas reinhardi, cr-1, is characterized. The mutation exhibits Mendelian inheritance and affects the sedimentation velocity and formation of intact chloroplast ribosomes. The mutant grows reasonably well when supplied with sodium acetate as a carbon source, but poorly when forced to grow photosynthetically using carbon dioxide. Since the mutant cr-1 accumulates large subunits of the chloroplast ribosome, we postulate that it is blocked in the formation of the small subunit. A tentative model explaining the behavior of the several mutants in Chlamydomonas now known to have altered chloroplast ribosomal phenotypes is presented.