Formation of the alpha 1-microglobulin chromophore in mammalian and insect cells : a novel post-translational mechanism?
(1995) In FEBS Letters 362(1). p.4-50- Abstract
alpha 1-Microglobulin is an immunosuppressive plasma protein synthesized by the liver. The isolated protein is yellow-brown, but the hypothetical chromophore has not yet been identified. In this work, it is shown that a human liver cell line, HepG2, grown in a completely synthetic and serum-free medium, secretes alpha 1-microglobulin which is also yellow-brown, suggesting a de novo synthesis of the chromophore by the cells. alpha 1-Microglobulin isolated from the culture medium of insect cells transfected with the gene for rat alpha 1-microglobulin is also yellow-brown, suggesting that the gene carries information about the chromophore. Reduction and alkylation or removal of N- or O-linked carbohydrates by glycosidase treatment did not... (More)
alpha 1-Microglobulin is an immunosuppressive plasma protein synthesized by the liver. The isolated protein is yellow-brown, but the hypothetical chromophore has not yet been identified. In this work, it is shown that a human liver cell line, HepG2, grown in a completely synthetic and serum-free medium, secretes alpha 1-microglobulin which is also yellow-brown, suggesting a de novo synthesis of the chromophore by the cells. alpha 1-Microglobulin isolated from the culture medium of insect cells transfected with the gene for rat alpha 1-microglobulin is also yellow-brown, suggesting that the gene carries information about the chromophore. Reduction and alkylation or removal of N- or O-linked carbohydrates by glycosidase treatment did not reduce the colour intensity of the protein. An internal dodecapeptide (amino acid positions 70-81 in human alpha 1-microglobulin) was also yellow-brown. The latter results indicate that the chromophore is linked to the polypeptide. In conclusion, the results suggest that the alpha 1-microglobulin gene carries information activating a post-translational protein modification mechanism which is present in mammalian and insect cells.
(Less)
- author
- Åkerström, B LU ; Bratt, T and Enghild, J J
- organization
- publishing date
- 1995-03-27
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Alkylation, Alpha-Globulins/chemistry, Amino Acid Sequence, Animals, Cell Line, Glycosylation, Humans, Molecular Sequence Data, Moths, Oxidation-Reduction, Peptides/chemistry, Pigments, Biological/chemistry, Protein Processing, Post-Translational, Tumor Cells, Cultured
- in
- FEBS Letters
- volume
- 362
- issue
- 1
- pages
- 4 - 50
- publisher
- Wiley-Blackwell
- external identifiers
-
- pmid:7535251
- scopus:0028987341
- ISSN
- 0014-5793
- DOI
- 10.1016/0014-5793(95)00206-O
- language
- English
- LU publication?
- yes
- id
- d5125f0b-60f7-4923-ae1d-d25b2c8a7fef
- date added to LUP
- 2019-05-22 10:20:47
- date last changed
- 2025-04-04 14:03:44
@article{d5125f0b-60f7-4923-ae1d-d25b2c8a7fef,
abstract = {{<p>alpha 1-Microglobulin is an immunosuppressive plasma protein synthesized by the liver. The isolated protein is yellow-brown, but the hypothetical chromophore has not yet been identified. In this work, it is shown that a human liver cell line, HepG2, grown in a completely synthetic and serum-free medium, secretes alpha 1-microglobulin which is also yellow-brown, suggesting a de novo synthesis of the chromophore by the cells. alpha 1-Microglobulin isolated from the culture medium of insect cells transfected with the gene for rat alpha 1-microglobulin is also yellow-brown, suggesting that the gene carries information about the chromophore. Reduction and alkylation or removal of N- or O-linked carbohydrates by glycosidase treatment did not reduce the colour intensity of the protein. An internal dodecapeptide (amino acid positions 70-81 in human alpha 1-microglobulin) was also yellow-brown. The latter results indicate that the chromophore is linked to the polypeptide. In conclusion, the results suggest that the alpha 1-microglobulin gene carries information activating a post-translational protein modification mechanism which is present in mammalian and insect cells.</p>}},
author = {{Åkerström, B and Bratt, T and Enghild, J J}},
issn = {{0014-5793}},
keywords = {{Alkylation; Alpha-Globulins/chemistry; Amino Acid Sequence; Animals; Cell Line; Glycosylation; Humans; Molecular Sequence Data; Moths; Oxidation-Reduction; Peptides/chemistry; Pigments, Biological/chemistry; Protein Processing, Post-Translational; Tumor Cells, Cultured}},
language = {{eng}},
month = {{03}},
number = {{1}},
pages = {{4--50}},
publisher = {{Wiley-Blackwell}},
series = {{FEBS Letters}},
title = {{Formation of the alpha 1-microglobulin chromophore in mammalian and insect cells : a novel post-translational mechanism?}},
url = {{http://dx.doi.org/10.1016/0014-5793(95)00206-O}},
doi = {{10.1016/0014-5793(95)00206-O}},
volume = {{362}},
year = {{1995}},
}