Add like
Add dislike
Add to saved papers

Zero-trans uptake of L-tryptophan in the human erythrocyte.

Some results from ongoing studies of the transport of some neutral amino acids across the human erythrocyte membrane (L-tryptophan and L-leucine) at 25 degrees C are presented. The unidirectional flux into the cell at initial rate as a function of the substrate concentration can be described by a 3-parameter model (i.e. a carrier in parallel with an apparent leak component). From the estimated kinetic parameters an apparent membrane permeability of the carrier (substrate concentrations S1 smaller than Kzt 12) has been calculated. The permeability of L-tryptophan (1.03 . 10(-8) cm/sec) was significantly lower than the permeability of L-leucine (2.36 . 10(-7) cm/sec). The contribution of the leak permeability to the total permeability at low concentrations was about 10% for L-tryptophan, but only 1% for L-leucine. From inhibition studies it is indicated that L-tryptophan passing the membrane via theapparent leak component is transported by the L-leucine carrier, the affinity being low. The saturable component of L-tryptophan transport does not correspond to any known amino acid transport system, and it is thus strongly suggested that a new L-tryptophan specific transport system operating at physyological concentrations has been described.

Full text links

We have located links that may give you full text access.
Can't access the paper?
Try logging in through your university/institutional subscription. For a smoother one-click institutional access experience, please use our mobile app.

For the best experience, use the Read mobile app

Mobile app image

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app

All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

By using this service, you agree to our terms of use and privacy policy.

Your Privacy Choices Toggle icon

You can now claim free CME credits for this literature searchClaim now

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app