Introduction 1997 2002 2003 2003 2003 2002 1999 2001 2003 2006 Candidatus “Aciduliprofundum boonei 1 1988 1998 2004 Aciduliprofundum boonei Fig. 1 Candidatus “Aciduliprofundum boonei” Inset 1998  Materials and methods Culture conditions Aciduliprofundum boonei 2006 Core lipid analysis A. boonei 2 2 3 4 2002 4 1998 4 m/z 2000 2 m/z Intact polar lipid analysis A. boonei 1959 2 2 4  2 .  2004 2006 −1 3aq 3aq sn sn sn l sn rac sn l 2 2 m/z Results and discussion Core lipids A. boonei 1 1988 2005 A. boonei 2006 1988 2004 2004 1 + 2000 4 1998 40 80 1998 Methanothermus fervidus A. boonei 1998 2007 1998 Methanothermus fervidus 1998 2004 A. boonei A. boonei Intact polar lipids A. boonei 2 m/z 2 m/z + 2004 + 2004 2005 A. boonei Fig. 2 Candidatus “Aciduliprofundum boonei” Inset  Conclusions Candidatus “Aciduliprofundum boonei” A. boonei