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Accelerated secretion of human lysozyme with a disulfide bond mutation.
- Source :
-
European journal of biochemistry [Eur J Biochem] 1992 Apr 15; Vol. 205 (2), pp. 551-9. - Publication Year :
- 1992
-
Abstract
- The mutant human lysozyme, [Ala77, Ala95]lysozyme, in which the disulfide bond Cys77-Cys95 is eliminated, is known to exhibit increased secretion in yeast, compared to wild-type human lysozyme [Taniyama, Y., Yamamoto, Y., Nakao, M., Kikuchi, M. & Ikehara, M. (1988) Biochem. Biophys. Res. Commun. 152, 962-967]. To investigate this phenomenon, mammalian cells were used to analyze the secretion kinetics of [Ala77, Ala95]lysozyme and wild-type human lysozyme. The secretion rate of [Ala77, Ala95]lysozyme during the 150-min chase period was significantly accelerated [half-life (t1/2) = 29 min] compared to that of wild-type human lysozyme (t1/2 = 83 min), when expressed at the same levels within the cells. In contrast, after the 150-min chase, the rates of disappearance of both wild-type and mutant human lysozymes within the cells were similar, and considerably slower (t1/2 = 220 min), respectively. The remaining intracellular wild-type human lysozyme was localized mainly in the endoplasmic reticulum, whereas accelerated transport of the [Ala77, Ala95]lysozyme mutant protein from the endoplasmic reticulum to the Golgi apparatus was observed. Also in yeast cells, similar secretion kinetics and the differences in t1/2 for wild-type and mutant human lysozymes during the early chase period were observed. The two-phase kinetics of disappearance of intracellular human lysozymes suggest that only a proportion of the proteins becomes secretion competent soon after synthesis and is completely secreted during the early chase period, whereas others enter the distinct, slow pathways of intracellular transport and/or degradation. Increased secretion of [Ala77, Ala95]lysozyme is possibly due to enhanced competence for secretion acquired in the endoplasmic reticulum at the early stage of transport events, which is closely connected with the removal of a disulfide bond.
- Subjects :
- Adenocarcinoma
Alanine
Amino Acid Sequence
Animals
Base Sequence
Cell Line
Cloning, Molecular
Disulfides
Gene Expression
Genes, Synthetic
Humans
Kinetics
L Cells
Mice
Molecular Sequence Data
Muramidase metabolism
Oligodeoxyribonucleotides
Plasmids
RNA, Messenger genetics
RNA, Messenger metabolism
Recombinant Proteins metabolism
Restriction Mapping
Saccharomyces cerevisiae genetics
Transfection
Vero Cells
Muramidase biosynthesis
Muramidase genetics
Mutation
Recombinant Proteins biosynthesis
Subjects
Details
- Language :
- English
- ISSN :
- 0014-2956
- Volume :
- 205
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- European journal of biochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 1572356
- Full Text :
- https://doi.org/10.1111/j.1432-1033.1992.tb16812.x