From Wikipedia,
the free encyclopedia.
Auxotrophy is the
inability of an organism to
synthesize a particular
organic compound required for
its growth (as defined by
IUPAC). An auxotroph is an
organism that displays this
characteristic; auxotrophic
is the corresponding adjective.
Auxotrophy is the opposite of
prototrophy.
In
genetics, a
strain is said to be
auxotrophic if it carries a
mutation that renders it
unable to synthesise an essential
compound. For example a
yeast mutant in which a gene
of the
uracil synthesis pathway is
inactivated is a uracil auxotroph.
Such a strain is unable to
synthesise uracil and will only be
able to grow if uracil can be
taken up from the environment.
This is the opposite of a uracil
prototroph, or in this case a
wild-type strain, which can
still grow in the absence of
uracil. Auxotrophic genetic
markers are often used in
molecular genetics.
