XMP + NH4(+) + ATP => GMP + AMP + diphosphate + 2 H(+)
xmp + nh4(+) + atp => gmp + amp + diphosphate + 2 h(+)
XMP + NH4(+) + ATP => GMP + AMP + diphosphate + 2 H(+)
xmp + nh4(+) + atp => gmp + amp + diphosphate + 2 h(+)