If an enzyme derived from a eukaryotic organism is deglycosylated prior to forming a conjugate, i.e. prior to attaching the enzyme to a molecule capable of binding to a target molecule, the sensitivity of an assay for detecting the presence or determining the quantity of a target molecule, in which the conjugate is used as a labelled component, can be increased. The present invention provides conjugates, methods for providing the same, use of such conjugates as well as kits containing the conjugates.