nicotinate(in) + a carboxylate(out) <=> nicotinate(out) + a carboxylate(in)
nicotinate(in) + a carboxylate(out) <=> nicotinate(out) + a carboxylate(in)
nicotinate(in) + a carboxylate(out) <=> nicotinate(out) + a carboxylate(in)
nicotinate(in) + a carboxylate(out) <=> nicotinate(out) + a carboxylate(in)