Location of a novel type of interpolypeptide chain linkage in the human protein HC-IgA complex (HC-IgA) and identification of a heterogeneous chromophore associated with the complex
(1994) In The Journal of biological chemistry 269(1). p.384-389- Abstract
Protein HC (human complex-forming glycoprotein, heterogeneous in charge) is a member of the lipocalin superfamily of hydrophobic ligand-binding proteins. The quantitatively dominating blood plasma form of protein HC is a protein HC-IgA complex (HC-IgA), which is the fourth most abundant immunoglobulin species in plasma. A photodiode array detection system on-line with a high performance liquid chromatograph has allowed the identification of low amounts of a heterogeneous fluorescent chromophore covalently bound to HC-IgA, and displaying significant absorption in the visible region in resemblance to the free protein HC chromophore. Several structurally related chromophore-containing linked peptides, carrying 80% of the light absorption... (More)
Protein HC (human complex-forming glycoprotein, heterogeneous in charge) is a member of the lipocalin superfamily of hydrophobic ligand-binding proteins. The quantitatively dominating blood plasma form of protein HC is a protein HC-IgA complex (HC-IgA), which is the fourth most abundant immunoglobulin species in plasma. A photodiode array detection system on-line with a high performance liquid chromatograph has allowed the identification of low amounts of a heterogeneous fluorescent chromophore covalently bound to HC-IgA, and displaying significant absorption in the visible region in resemblance to the free protein HC chromophore. Several structurally related chromophore-containing linked peptides, carrying 80% of the light absorption at 330 nm of HC-IgA, were isolated from a pepsin-produced protein HC-alpha 1-nonapeptide. Sequence analysis of these linked peptides demonstrated that the bond between protein HC and IgA represents a novel type of reduction-resistant linkage between polypeptide chains and involves the cysteine residue 34 of protein HC and the penultimate cysteine residue of the carboxyl-terminal part of one of the IgA heavy chains, as well as the heterogeneous fluorescent chromophore. The light absorption and fluorescent spectra of the chromophore-linked peptides were similar to those of native free protein HC.
(Less)
- author
- Calero, M ; Escribano, J ; Grubb, Anders LU and Méndez, E
- publishing date
- 1994
- type
- Contribution to journal
- publication status
- published
- keywords
- Alpha-Globulins/chemistry, Amino Acid Sequence, Chromatography, High Pressure Liquid, Fluorescent Dyes, Humans, Immunoglobulin A/chemistry, Molecular Sequence Data, Oligopeptides/analysis, Pepsin A/metabolism, Protease Inhibitors/chemistry, Spectrum Analysis
- in
- The Journal of biological chemistry
- volume
- 269
- issue
- 1
- pages
- 384 - 389
- publisher
- American Society for Biochemistry and Molecular Biology
- external identifiers
-
- scopus:0028057820
- pmid:7506257
- ISSN
- 0021-9258
- language
- English
- LU publication?
- no
- id
- 7021b33a-a921-4dd0-88d3-a1d2c317c577
- alternative location
- https://www.sciencedirect.com/science/article/pii/S0021925817423611
- date added to LUP
- 2021-10-28 13:37:26
- date last changed
- 2024-01-12 02:57:14
@article{7021b33a-a921-4dd0-88d3-a1d2c317c577, abstract = {{<p>Protein HC (human complex-forming glycoprotein, heterogeneous in charge) is a member of the lipocalin superfamily of hydrophobic ligand-binding proteins. The quantitatively dominating blood plasma form of protein HC is a protein HC-IgA complex (HC-IgA), which is the fourth most abundant immunoglobulin species in plasma. A photodiode array detection system on-line with a high performance liquid chromatograph has allowed the identification of low amounts of a heterogeneous fluorescent chromophore covalently bound to HC-IgA, and displaying significant absorption in the visible region in resemblance to the free protein HC chromophore. Several structurally related chromophore-containing linked peptides, carrying 80% of the light absorption at 330 nm of HC-IgA, were isolated from a pepsin-produced protein HC-alpha 1-nonapeptide. Sequence analysis of these linked peptides demonstrated that the bond between protein HC and IgA represents a novel type of reduction-resistant linkage between polypeptide chains and involves the cysteine residue 34 of protein HC and the penultimate cysteine residue of the carboxyl-terminal part of one of the IgA heavy chains, as well as the heterogeneous fluorescent chromophore. The light absorption and fluorescent spectra of the chromophore-linked peptides were similar to those of native free protein HC.</p>}}, author = {{Calero, M and Escribano, J and Grubb, Anders and Méndez, E}}, issn = {{0021-9258}}, keywords = {{Alpha-Globulins/chemistry; Amino Acid Sequence; Chromatography, High Pressure Liquid; Fluorescent Dyes; Humans; Immunoglobulin A/chemistry; Molecular Sequence Data; Oligopeptides/analysis; Pepsin A/metabolism; Protease Inhibitors/chemistry; Spectrum Analysis}}, language = {{eng}}, number = {{1}}, pages = {{384--389}}, publisher = {{American Society for Biochemistry and Molecular Biology}}, series = {{The Journal of biological chemistry}}, title = {{Location of a novel type of interpolypeptide chain linkage in the human protein HC-IgA complex (HC-IgA) and identification of a heterogeneous chromophore associated with the complex}}, url = {{https://www.sciencedirect.com/science/article/pii/S0021925817423611}}, volume = {{269}}, year = {{1994}}, }