Relationship among proteobacterial species that have the SHP operon. The figure is based upon Bergey's Manual of Systematic Bacteriology, which is essentially a 16S rRNA based classification . The five classes are indicated by greek letters. Species that have SK1, SK2, or SK3 regulatory genes as part of the SHP operon are indicated. There are genome sequences for all but Mp. methylotrophus, Beggiatoa sp., and the Rhodobacteraceae in this study for which there is no information on regulation. Additional closely related SHP-containing species, Bh. multivorans, Bh. vietnamensis, Bh. phymatum, Bh. glumae, Sh. putrefaciens, Sh. baltica, Ms. magnetotacticum, Ms. gryphiswaldense, and Tc. tepidum, are not shown because of space limitations.
Meyer et al. BMC Biochemistry 2010 11:24 doi:10.1186/1471-2091-11-24