Two hypotheses--one answer. Sequence comparison does not support an evolutionary link between halobacterial retinal proteins including bacteriorhodopsin and eukaryotic G-protein-coupled receptors.

J Soppa

doi:10.1016/0014-5793(94)80573-3

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Two hypotheses--one answer. Sequence comparison does not support an evolutionary link between halobacterial retinal proteins including bacteriorhodopsin and eukaryotic G-protein-coupled receptors.

J Soppa

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Abstract

The structure of bacteriorhodopsin (BR) of Halobacterium halobium is known. Despite the lack of sequence similarities it is often taken as a model for eukaryotic G-protein-coupled receptors (GPCRs). Recently two hypotheses were used to support the homology of BR and GPCRs, namely evolution by exon shuffling and evolution by gene duplication. BR is a member of a family of halobacterial retinal proteins. The sequences of eight members of this family were used to test the two hypotheses. Based on sequence comparison, no indication for an evolutionary linkage between the two protein families could be found.

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Amino Acid Sequence Animals Bacteriorhodopsins Biological Evolution Exons GTP-Binding Proteins Halobacterium salinarum Halorhodopsins Humans Molecular Sequence Data Multigene Family Protein Structure, Secondary Receptors, Cell Surface Sequence Alignment Journal Article

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J Soppa. 1994-03-28. Two hypotheses--one answer. Sequence comparison does not support an evolutionary link between halobacterial retinal proteins including bacteriorhodopsin and eukaryotic G-protein-coupled receptors.. https://doi.org/10.1016/0014-5793(94)80573-3

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