Synthesis, processing and degradation in yeast of precursor human lysozyme with newly designed signal sequences

Recently, we reported that the synthesis of human lysozyme in yeast is inhibited when artificially designed non-native signal sequences are used [Yamamoto et al. (1987) Biochem. Biophys. Res. Commun. 149, 431-436; (1989) Biochemistry 28, 2728-2732]. Pulse/chase experiments described in the present paper have now revealed that precursor lysozymes are actually synthesized with these signal sequences, but that they are spontaneously degraded, suggesting that the enzyme is destabilized by the signal sequences. The data further show a good correlation between the secretory capability of the artificial signal sequences and the efficiency of the processing of precursor lysozyme.