= Aspartate
<Aspartate> denotes an anionic form of <aspartic acid>. A common biochemical example is the L-configured monoanion, with two <carboxylate> groups and one positively charged amino group. Its formula is $\mathrm{C_4H_6NO_4^-}$ and its net charge is $-1$.<Aspartate in ChEBI>[CHEBI:29991; L-aspartate(1−), formula, charge and structure]{ref}
The charge count is
$$
(-1)+(-1)+(+1)=-1.
$$
Having both positive and negative groups therefore does not imply a zero total charge. Compared with neutral <aspartic acid>, formation of this conjugate base removes a proton; it does not change the four-carbon connectivity or, by itself, reverse the L/D <stereochemistry>.
An illustrative acid–base comparison keeps these questions separate. For one protonation step in a dilute solution, the <Henderson-Hasselbalch equation> gives $[\mathrm{base}]/[\mathrm{acid}]\simeq10^{\mathrm{pH}-\mathrm{p}K_a}$. One pH unit above that step's $\mathrm{p}K_a$ gives a ratio of about ten. This is a symbolic illustration, not a numerical assignment of the molecule's several dissociation constants. Specifying ionic form, <pH> and <stereochemistry> is more informative than treating every use of the name <aspartate> as one context-free structure.
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