9.B.358.  The DUF350 domain-containing (DUF350) Family 

This family consists of many integral membrane proteins of 250 to 300 aas with 8 TMSs in a 1 + 2 + 2 + 2 + 1 TMS arrangement, of 4 TMS proteins of half this size with a 1 + 2 + 1 TMS arrangement, and 2 TMS proteins of half this size. They derivse from a variety of bacteria and archaea.  Their functions are unknown.