Low-affinity peptide transporter that is necessary for proton-dependent uptake of di- or tripeptides, and to a minor extent tetrapeptides, in the intestine. Transport is independent of sodium and chloride ions. Controls the uptake of dietary fatty acids, plays a role in fatty acid synthesis and is responsible for dipeptide-induced acidification of the intestine. Regulates cellular pH differences together with the antiporter protein, nhx-2. Amino acid uptake and absorption levels influence the insulin signaling/daf-2 and let-363/TOR pathways, subsequently affecting the stress response and longevity of the organism. It is required for the uptake of the L-enantiomers of various amino acids, including L-glutamate (PubMed:30560135). In response to the availability of amino acid nutrients, may play a role in promoting reproduction and fertility (PubMed:30560135). Colocalizes with nhx-2 along the apical membrane of the intestinal cells. Expressed specifically in the intestine. Biphasic expression pattern observed. Gradual increase in expression during development from embryo through to adult with a decrease during larva stages 1 and 2. Mutant worms have decreased body size, high fat stores, increased uptake of fatty acids, reduced brood size, retarded postembryonic growth, extended reproductive life span and increased resistance to stress. RNAi-mediated knockdown of the protein results in impaired synthesis of long-chain and polyunsaturated fatty acids. Pharyngeal pumping rate is similar to wild type but simultaneous knockdown with nhx-2 results in reduced rate of pharyngeal pumping and slightly higher acidic intestinal pH. Belongs to the major facilitator superfamily. Proton-dependent oligopeptide transporter (POT/PTR) (TC 2.A.17) family.