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Molecular phylogeny of Dictyostelium discoideum by protein sequence comparison.

ABSTRACT: Comparison of the amino acid sequences of eight proteins from the soil amoeba Dictyostelium discoideum to those of their homologs in bacteria, yeast, and other eukaryotes indicates that Dictyostelium diverged from the line leading to mammals at about the same time as the plant/animal divergence. Yeast appear to have diverged considerably earlier. It is argued that previous analyses indicating that D. discoideum diverged before yeast were misleading because of the nature of the small ribosomal subunit rRNA sequences used in these studies. We suggest that amino acid sequences may be more reliable than untranslated nucleic acid sequences for evolutionary comparisons, especially among organisms with significant skewing of their A+T content.

SUBMITTER: Loomis WF

PROVIDER: S-EPMC55110 | biostudies-other | 1990 Dec

REPOSITORIES: biostudies-other

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Molecular phylogeny of Dictyostelium discoideum by protein sequence comparison.

Loomis W F WF Smith D W DW

Proceedings of the National Academy of Sciences of the United States of America 19901201 23

Comparison of the amino acid sequences of eight proteins from the soil amoeba Dictyostelium discoideum to those of their homologs in bacteria, yeast, and other eukaryotes indicates that Dictyostelium diverged from the line leading to mammals at about the same time as the plant/animal divergence. Yeast appear to have diverged considerably earlier. It is argued that previous analyses indicating that D. discoideum diverged before yeast were misleading because of the nature of the small ribosomal su ...[more]

PMID: 2251251

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