Three-Dimensional assembly of subunits
molecule is a tetrameric structural
that comprises two alpha and
two beta subunits. The
arrangement comprises two symmetrical alpha + beta subunit halves.
Other quaternary structures may comprise a dozen or more polypeptides,
all of which are distinct. [The
inorganic heme groups are
modifications of the tertiary structure of the individuals monomers,
but are not
typical of quaternary structure].
Figure © 2002 by Griffiths
et al. ; All
material ©2010 by Steven M.