Isomerization of n-decane in the presence of 1000 ppm H2S was studied on bifunctional Pt-MAPSO-31 catalysts. Sulfur suppresses the catalyst metal function, thereby changing the metal-acid balance which is required for high performance. Methods for controlling the catalyst metal-acid balance by changing the ratio between metal and acid functions are demonstrated. Catalysts with high isomerization selectivity in the presence of sulfur should have a strong metal function. Close proximity of metal and acid sites, as well as highly dispersed metal located on the binder, gives a catalyst with an isomerization selectivity of about 90%. This is similar to selectivity of the same catalyst in the absence of sulfur.