$\begin{array}{*{20}{c}}
  {{H_3}\mathop N\limits^ \oplus   - CH - COOH} \\ 
  {|\,\,\,\,\,\,\,\,\,\,} \\ 
  {C{H_3}\,\,} 
\end{array}$  $\underset{{O{H^\Theta }}}{\overset{{{H^ \oplus }}}{\longleftrightarrow}}$ $\begin{array}{*{20}{c}}
  {{H_3}\mathop {\mathop N\limits^ \oplus   - CH - CO{O^\Theta }}\limits^{} } \\ 
  {|{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} } \\ 
  {C{H_3}} 
\end{array}$ $\underset{{^\Theta OH}}{\overset{{{H^ \oplus }}}{\longleftrightarrow}}$  $\begin{array}{*{20}{c}}
  {{H_2}N - CH - CO{O^\Theta }} \\ 
  {|\,\,\,\,\,\,\,\,} \\ 
  {\,C{H_3}\,\,} 
\end{array}$