PROSITE documentation PDOC00681

Sodium:alanine symporter family signature

It has been shown [1] that integral membrane proteins that mediate the intake of a wide variety of molecules with the concomitant uptake of sodium ions (sodium symporters) can be grouped, on the basis of sequence and functional similarities into a number of distinct families. One of these families is known as the sodium:alanine symporter family (SAF) and currently consists of the following proteins:

• Thermophilic bacterium PS-3 alanine carrier protein (ACP). ACP can use both sodium and hydrogen as a symport ion.
• Alteromonas haloplanktis D-alanine/glycine permease (gene dagA).
• Bacillus subtilis alsT.
• Hypothetical protein yaaJ from Escherichia coli and HI0183, the corresponding Haemophilus influenzae protein.
• Haemophilus influenzae hypothetical protein HI0883.

These integral membrane proteins are predicted to comprise a least eight membrane spanning domains. As a signature pattern we selected a highly conserved region which is located in the N-terminal section and which includes part of the first transmembrane region.