Beta-1,2-xylosyltransferase that plays a key role in capsule polysaccharide synthesis by transferring xylose to alpha-1,3-dimannoside in a beta-1,2-linkage. Also mediates glycosylation of glycosphingolipids; constitutes the unique xylosyltransferase responsible for adding xylose to glycosphingolipids. Attenuation of cryptococcal growth in a mouse model of infection due to defects in capsule polysaccharide content. The general morphology of the capsule is normal but two main capsule polysaccharides, glucuronoxylomannan (GXM) and galactoxylomannan (GalXM), lack beta-1,2-xylose residues. Belongs to the glycosyltransferase 90 family.