POT Family

Family 2.A.17 - The Proton-dependent Oligopeptide Transporter Family

Family ID: 52622

Proteins of the POT family (also called the PTR (peptide transport) family) consist of proteins from animals, plants, yeast, archaea and both Gram-negative and Gram-positive bacteria. Several of these organisms possess multiple POT family paralogues. The proteins are of about 450-600 amino acyl residues in length with the eukaryotic proteins in general being longer than the bacterial proteins. They exhibit 12 putative or established transmembrane a-helical spanners. Some members of the POT family exhibit limited sequence similarity to protein members of the major facilitator superfamily (MFS; TC #2.A.1). (Comparison scores of up to 8 standard deviations for segments in excess of 60 residues in length.) Thus the POT family is probably a family within the MFS.

While most members of the POT family catalyze peptide transport, one is a nitrate permease and one can transport histidine as well as peptides. Some of the peptide transporters can also transport antibiotics. They function by proton symport, but the substrate:H+ stoichiometry is variable: the high affinity rat PepT2 carrier catalyzes uptake of 2 and 3H+ with neutral and anionic dipeptides, respectively, while the low affinity PepT1 carrier catalyzes uptake of one H+ per neutral peptide. In eukaryotes, some of these transporters may be in organellar membranes such as the lysosomes.

	Options		Family References
	Search for the most up-to-date list of family members Want to help us annotate this family?		No references yet (if you have one please annotate!)

	Arabidopsis Families
	At1g12110 CHL1 nitrate/chlorate transporter At1g18880 hypothetical protein At1g22540 Similar to peptide transporter At1g22550 Similar to LeOPT1 At1g22570 Similar to LeOPT1 At1g27040 nitrate transporter, putative At1g27080 nitrite transporter, putative At1g32450 peptide transporter PTR2-B, putative At1g33440 nitrate transporter NTL1, putative At1g52190 putative peptide transporter At1g59740 hypothetical protein At1g62200 hypothetical protein At1g68570 peptide transporter, putative At1g69850 NTL1 nitrate transporter At1g69860 putative peptide transporter At1g69870 putative peptide transporter At1g72120 hypothetical protein At1g72130 peptide transporter PTR2-B, putative At1g72140 peptide transporter PTR2-B, putative At2g02020 putative peptide amino acid transporter At2g02040 Ptr2B histidine transport protein At2g26690 putative nitrate transporter At2g37900 putative peptide/amino acid transporter At2g38100 putative peptide/amino acid transporter At2g40460 putative PTR2 family peptide transporter		At3g01350 putative peptide transporter At3g16180 putative transport protein At3g21670 nitrate transporter At3g25260 nitrate transporter, putative At3g25280 nitrate transporter, putative At3g45650 putative protein At3g45660 putative protein At3g45680 putative transporter protein At3g45690 putative transporter protein At3g45700 putative transporter protein At3g45710 putative transporter protein At3g45720 putative transporter protein At3g47960 putative peptide transporter At3g53960 transporter-like protein At3g54140 peptide transport - like protein At3g54450 oligopeptide transporter -like protein At4g21680 peptide transporter - like protein At5g01180 oligopeptide transporter - like protein At5g11570 putative oligopeptide transporter protein At5g13400 peptide transporter - like protein At5g14940 oligopeptide transporter -like protein At5g19640 peptide transport protein-like At5g28470 peptide transporter - like protein At5g46040 peptide transporter At5g46050 peptide transporter At5g62680 peptide transporter At5g62730 nitrate transporter NTL1 - like protein
	Yeast Families
	YKR093W PTR2 di- and tripeptide permease
	Rice Families (Coming Soon!)

© 2000-2002, Purdue University (in San Diego)
San Diego Supercomputer Center