The nucleotide sequence of blue-green algae phenylalanine-tRNA and the evolutionary origin of chloroplasts

摘要

Phenylalanine tRNA from the blue-green alga, Agmenellum quadruplicatum, has been purified to homogeneity. The nucleotide sequence of this tRNA was determined to be: pG-C-C-A-G-G-A-U-A-G-C-U*-C-A-G-U-D-Gm-G-D-A-G-A-G-C-A-G-A-G-G-A-C-U-G-A-A-ms2i6 A-A-f-C-C-U-C-G-U-m7 G-U-C-G-G-C-G-G-T-Ψ-C-A-A-U-U-C-C-G-C-C-U-C-C-C-G-G-C-A-C-C-A. Comparisons of the sequence and-the modified nucleosides of this tRNA with those of other tRNAPhes thus far sequenced, indicate that this blue green algal tRNA e is logically prokaryotic and closely resembles the chloroplast tRNAPhes of higher plants and Euglena. The significance of this observation to the evolutionary origin of chloroplasts is discussed.