xanthine(out) + ATP + H2O <=> xanthine(in) + ADP + phosphate + H(+)
xanthine(out) + atp + h2o <=> xanthine(in) + adp + phosphate + h(+)
xanthine(out) + ATP + H2O <=> xanthine(in) + ADP + phosphate + H(+)
xanthine(out) + atp + h2o <=> xanthine(in) + adp + phosphate + h(+)