Ceramide hydroxylase involved in the hydroxylation of sphingolipid-associated very long chain fatty acids (PubMed:9353282, PubMed:9368039, PubMed:26977056, PubMed:9559540, PubMed:16652392, PubMed:19074599). Postulated to hydroxylate the very long chain fatty acid of dihydroceramides and phytoceramides at C-2 (PubMed:9368039, PubMed:26977056). an N-(1,2 saturated acyl)-(4R)-hydroxysphinganine + 2 Fe(II)-[cytochrome b5] + 2 H(+) + O2 = an N-(2R-hydroxyacyl)-4R-hydroxysphinganine + 2 Fe(III)-[cytochrome b5] + H2O an N-(1,2-saturated acyl)sphinganine + 2 Fe(II)-[cytochrome b5] + 2 H(+) + O2 = an N-[(2'R)-hydroxyacyl]sphinganine + 2 Fe(III)-[cytochrome b5] + H2O 2 Fe(II)-[cytochrome b5] + 2 H(+) + N-hexacosanoyl-(4R)-hydroxysphinganine + O2 = 2 Fe(III)-[cytochrome b5] + H2O + N-(2-hydroxyhexacosanyl)-(4R)-hydroxysphinganine Binds 2 Zn(2+) ions per subunit that likely form a catalytic dimetal center. Sphingolipid metabolism. The histidine box domains may contain the active site and/or be involved in metal ion binding. Causes a lack of alpha-hydroxylated very long chain fatty acids in yeast sphingolipids. This confers resistance to syringomycin E, an antifungal cyclic lipodepsinonapeptide produced by Pseudomonas syringae. Present with 3290 molecules/cell in log phase SD medium. Belongs to the sterol desaturase family. SCS7 subfamily.