Dephosphorylates the phosphotyrosine-containing proteins. Involved in ethanol stress resistance. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Efficiently inhibited by Cu(2+) ion, Zn(2+) ion and N-ethylmaleimide, while the addition of Mg(2+), Ca(2+) or Fe(3+) ions has minimal effect. Inhibited in a competitive manner by vanadate. Optimum pH is 6.0. By ethanol stress. Expression is sigma B-dependent. Belongs to the low molecular weight phosphotyrosine protein phosphatase family.