Oxyfunctionalization of fatty acids (FAs) is ak ey step in the design of novel synthetic pathways for biobased/ biodegradable polymers, surfactants and fuels. Here, we show the isolation and characterizationo farobust FA a-hydroxylase (P450 Ja)w hich catalyses the selective conversion of ab road range of FAs(C6:0-C16:0) and oleic acid (C18:1) with H 2 O 2 as oxidant. Under optimized reaction conditions P450 Ja yields a-hydroxy acids all with > 95 %r egioselectivity, high specific activity (up to 15.2 Umg À1)a nd efficient coupling of oxidant to product (up to 85 %). Lauric acid (C12:0) turned out to be an excellent substrate with respectt op ro-ductivity (TON = 394 min À1). On preparative scale, conversion of C12:0r eached 83 %(0.9 gL À1)w hen supplementing H 2 O 2 in fed-batch mode. Under similarc onditions P450 Ja allowed further the first biocatalytic a-hydroxylation of oleic acid (88 %c onversion on 100 mL scale) at high selectivity and in good yields (1.1 gL À1 ;7 9% isolatedy ield). Unexpectedly, P450 Ja displayed also 1-alkenef ormationf rom shorter chain FAs(C10:0) showingt hat oxidative decarboxylation is more widely distributed across this enzyme family than reportedp reviously.