Talk:Carrier protein

Untitled

At present this states the following:

Embedded in the cell membrane these proteins transport substances against the concentration gradient out of or into the cell. Therefore carrier proteins conduct facilitated diffusion and active transport. Each carrier protein is designed to recognize one substance or one group of very similar substances only.

It should be noted that this must be wroong in some way as facilitated diffusion does not occur against a concentration gradient but with it!

Cat

Would it be appropriate to put this article into Category:transport proteins, or is there a difference between carrier and transport proteins? If not, should this article be merged with transport protein? Thanks, delldot | talk 07:18, 9 January 2007 (UTC)

three other meanings

According to the IUPAC Compendium of Chemical Terminology, 2004, the term "carrier protein" has several meanings: 1. Protein to which a specific ligand or hapten is conjugated. 2. Unlabeled protein introduced into an assay at relatively high concentrations which distributes in a fractionation process in the same manner as labeled protein analyte, present in very low concentrations. 3. Protein added to prevent non-specific interaction of reagents with surfaces, sample components, and each other. 4. Protein found in cell membranes, which facilitates transport of a ligand across the membrane. The present article focuses only on definition #4, but should be amended in some way to reflect the various meanings rather than focusing on just one. Anyone know how to handle this situation? bwbrian (talk) 16:23, 8 May 2008 (UTC)

Could move this article to say cell membrane carrier protein and make carrier protein a disambiguation article ? Keyhole_limpet_hemocyanin#Use_in_biotechnology says it is used as a carrier protein in antibody manufacture - Could be meaning #1 ? - Rod57 (talk) 19:54, 2 August 2015 (UTC)

Meaning of Active Transport section?

The active transport section said (2/23/2012, 16:40): "Active transport involves the use of an electrochemical gradient, involves (sic) proteins s opposed to (sic) rier pro, and does not use (sic) nergy produced in the cell." And wasn't formatted correctly, appearing in a "code box" (I assume it's meant for computer code) instead of a normal paragraph. But I thought that the definition of active transport (as opposed to passive) was that it did use energy. I fixed for formatting of the code, but I don't know whether what was written was actually correct. What should this paragraph say? Jimw338 (talk) 00:03, 1 March 2012 (UTC)

what about proteins like hemoglobulin? — Preceding unsigned comment added by 200.23.162.206 (talk) 19:47, 10 October 2012 (UTC)

Assessment comment

The comment(s) below were originally left at Talk:Carrier protein/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

This page states that carrier proteins move substances DOWN (i.e., along) their concentration gradient by facilitated diffusion and ACTIVE TRANSPORT. This is incorrect. Whenever something is moved DOWN its concentration gradient, there is no energy requirement; it is a spontaneous process. Active transport is used to transport a substance AGAINST its concentration gradient. Facilitated diffusion is a passive, albeit protein-mediated process that moves a substance down its gradient. I am going to delete "active transport" from this entry. I am pretty sure that carrier proteins do not require an input of energy, but if they do then "active transport" should be reinstated and "passive transport" deleted.

Last edited at 17:55, 9 October 2007 (UTC). Substituted at 10:58, 29 April 2016 (UTC)