| Type: | Conserved_site | Name: | Tryptophan/tryrosine permease, conserved site |
| Description: | Amino acid permeases are integral membrane proteins involved in the transport of amino acids into the cell. A number of such proteins have been found to beevolutionary related [, , ].Aromatic amino acids are concentrated in the cytoplasm of Escherichia coliby 4 distinct transport systems: a general aromatic amino acid permease, and aspecific permease for each of the 3 types (Phe, Tyr and Trp) []. It has been shown [] that some permeases in E. coli and related bacteria are evolutionary related.These permeases are proteins of about 400 to 420 amino acids and are located in the cytoplasmic membrane and, like bacterial sugar/cation transporters, are thought to contain 12 transmembrane (TM) regions [] - hydropathy analysis, however, is inconclusive, suggesting thepossibility of 10 to 12 membrane-spanning domains []. The best conserved domain is a stretch of 20 residues which seems to be located in a cytoplasmic loop between thefirst and second transmembrane region.This entry represents a conserved site specific for tyryptophan and tyrosine permeases. | Short Name: | Trp/try_permease_CS |
