Protein Family Models

The OPT family of oligopeptide transporters is distinct from the ABC Pfam:PF00005 and PTR Pfam:PF00854 transporter families. OPT transporters were first recognised in fungi (Candida albicans and Schizosaccharomyces pombe), but this alignment also includes orthologues from Arabidopsis thaliana. OPT transporters are thought to have 12-14 transmembrane domains and contain the following motif: SPYxEVRxxVxxxDDP [1]. [1]. 9643541. Schizosaccharomyces pombe isp4 encodes a transporter representing a novel family of oligopeptide transporters. Lubkowitz MA, Barnes D, Breslav M, Burchfield A, Naider F, Becker JM;. Mol Microbiol 1998;28:729-741. (from Pfam)

Date:

2024-10-16

OPT family oligopeptide transporter may be involved in the translocation of oligopeptides such as tetra- and pentapeptides across the cellular membrane in an energy-dependent manner

Date:

2019-05-18

This superfamily has two main branches. One branch contains a tetrapeptide transporter demonstrated experimentally in three different species of yeast. The other family contains EspB of Myxococcus xanthus, a protein required for normal rather than delayed sporulation after cellular aggregation; its role is unknown but is compatible with transport of a signalling molecule. Homology between the two branches of the superfamily is seen most easily at the ends of the protein. The central regions are poorly conserved within each branch and may not be homologous between branches.

Date:

2024-07-12

This protein represents a small family of integral membrane proteins from Gram-negative bacteria, a Gram-positive bacteria, and an archaeal species. Members of this family contain 15 to 18 GES predicted transmembrane regions, and this family has extensive homology to a family of yeast tetrapeptide transporters, including isp4 (Schizosaccharomyces pombe) and Opt1 (Candida albicans). EspB, an apparent equivalog from Myxococcus xanthus, shares an operon with a two component system regulatory protein, and is required for the normal timing of sporulation after the aggregation of cells. This is consistent with a role in transporting oligopeptides as signals across the membrane.

Date:

2024-07-09