 Given the abundance of xylose and its potential for the bioconversion of lignocellulosic materials to renewable fuels, "Pichia stipitis" has been extensively studied.The complete sequencing of its genome was announced in 2007.Native strains of "S. stipitis" have been shown to produce ≈50 g/l ethanol in 48 h from pure xylose in defined minimal medium using urea as a nitrogen source.