9.B.227.  The Uncharacterized 9 or 10 TMS YndJ (YndJ) Family 

Nothing is known about the functions of these proteins, but many are present in the NCBI protein database as it is a large family of conserved membrane proteins. The YndJ family includes numberous proteins of about the same size and topology.  One publication described work on a homologue of this family, but the function was not revealed (Joshi and McSpadden Gardener 2006).