Dolichol-linked oligosaccharide (DLO) pyrophosphatase; involved in homeostasis/quality control of DLO by converting it into phosphorylated oligosaccharides; mRNA translated through programmed +1 translational frameshifting via tRNA slippage; orthologs encode members of VanZ family proteins, found in various bacteria and fungi; likely to be localized to Golgi; knock-out shows abnormal accumulation of DLO modified by Golgi mannosyltransferases