Indications of spatial relations among structures recognizing amino acids and Na+ at a transport receptor site

The orientation of the hydroxyl group on carbons 3 or 4 of proline, whether cis or trans, is decisive to the interaction between the amino acid and Na+ for a Na+-linked transport system of the pigeon erythrocyte and the rabbit reticulocyte. Consideration of this response in relation to other strong effects of the position of the hydroxyl group in two transport systems suggests that at the transport receptor site under study, the two substrates bind in juxtaposition, Na+ trans to the carboxyl group of the amino acid.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32729/1/0000097.pd