| Value |
175
molecules of water/fructose
|
| Organism |
Mammalian tissue culture cell |
| Reference |
Ashmore J. Cochlear outer hair cell motility. Physiol Rev. 2008 Jan88(1):173-210. doi: 10.1152/physrev.00044.2006 p.194 right column bottom paragraphPubMed ID18195086
|
| Primary Source |
[43] Chambard JM, Ashmore JF. Sugar transport by mammalian members of the SLC26 superfamily of anion-bicarbonate exchangers. J Physiol. 2003 Aug 1 550(Pt 3):667-77 DOI: 10.1113/jphysiol.2003.039321PubMed ID12938672
|
| Method |
Primary source abstract: "[Investigators] show both directly and indirectly that SLC26A5, rat prestin, takes up hexoses when expressed in several cell lines. Direct measurements of labelled fructose transport into COS-7 cells expressing prestin are reported here. Indirect measurements, using imaging techniques, show that transfected HEK-293 or CHO-Ki cells undergo reversible volume changes when exposed to isosmotic glucose-fructose exchange." |
| Comments |
P.194 right column bottom paragraph: "The discovery of prestin relegates the strict requirement of a sugar transporter in OHCs to a position of somewhat academic interest. Nevertheless, heterologously expressed prestin also transports fructose (primary source). The effect can be demonstrated by showing that cells presented with solutions where the glucose has been replaced isosmotically with fructose, like OHCs, swell with a Km of 24 mM, close to that found in OHCs. The transport rates for the whole cell that can be inferred are smaller than in OHCs, which is likely to reflect the lower copy numbers in the cell line. The calculated uptake of water is 175 molecules water per fructose transported. Similar water transport values for “water pumps” have been described for the Na-glucose cotransporter SGLT1 (ref 205)." |
| Entered by |
Uri M |
| ID |
117141 |