"Mechanism of Ammonia Transport by Amt/MEP/Rh: Structure of AmtB at 1.35Å" Makes the Cover of Science

[ Released September 10, 2004 ]

Mechanism of Ammonia Transport by Amt/MEP/Rh: Structure of AmtB at 1.35Å
Khademi, S., O'Connell III, J., Remis, J., Robles-Colmenares, Y., Miercke L.J.W., and Stroud, R.M.
Science 305, 1587-1594 (Cover Article, with Perspective by Knepper and Agre, 1573-1574)
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The manuscript was published in Science magazine, along with a perspective written by Peter Agre and Mark Knepper, and is illustrated by the deduced mechanism of these proteins illustrated on the front cover. The manuscript describes the first molecular structure, and the mechanism of a member of a family of membrane proteins, the Amt/MEP/Rh factor family. The mechanism is intriguing and fortells the mechanism of this important family that is found throughout all life forms. There are six Rh family members in humans.

Agre and Knepper describe the paper:

The article is a tour de force: it heralds spectacular future progress in elucidating the structures and functions of integral membrane proteins; it reveals a mechanism of ammonia permeation that is likely to be similar in membranes of eukaryotic cells. Thus, human Rh-related proteins are likely to play important roles in critical physiological processes and, when defective, to result in impairment of systemic pH regulation or central nervous system dysfunction due to ammonium toxicity. Moreover, the structure of Rh antigens has long been pondered, and the trimeric structure of AmtB suggests a simple explanation for how the three erythroid Rh polypeptides-RhAG, RhD, and RhCE-form the Rh antigen complex in the plasma membranes of erythrocytes.