Sökning: id:"swepub:oai:lup.lub.lu.se:7bf24ed3-fa34-4bf1-aca3-f8a450ddec71" >
Protein Arp and pro...
Protein Arp and protein H from group A streptococci. Ig binding and dimerization are regulated by temperature
-
- Akerström, B (författare)
- Lund University,Lunds universitet,Infektionsmedicin,Sektion III,Institutionen för kliniska vetenskaper, Lund,Medicinska fakulteten,Infection Medicine (BMC),Section III,Department of Clinical Sciences, Lund,Faculty of Medicine
-
- Lindahl, G (författare)
- Lund University,Lunds universitet,Avdelningen för medicinsk mikrobiologi,Institutionen för laboratoriemedicin,Medicinska fakulteten,Division of Medical Microbiology,Department of Laboratory Medicine,Faculty of Medicine
-
- Björck, L (författare)
- Lund University,Lunds universitet,Infektionsmedicin,Sektion III,Institutionen för kliniska vetenskaper, Lund,Medicinska fakulteten,Molekylär patogenes,Forskargrupper vid Lunds universitet,epIgG,Infection Medicine (BMC),Section III,Department of Clinical Sciences, Lund,Faculty of Medicine,Molecular Pathogenesis,Lund University Research Groups
-
visa fler...
-
- Lindqvist, A (författare)
- Lund University,Lunds universitet,Institutionen för experimentell medicinsk vetenskap,Medicinska fakulteten,Department of Experimental Medical Science,Faculty of Medicine
-
visa färre...
-
(creator_code:org_t)
- 1992
- 1992
- Engelska.
-
Ingår i: Journal of immunology. - 0022-1767. ; 148:10, s. 43-3238
- Relaterad länk:
-
https://www.jimmunol...
-
visa fler...
-
https://lup.lub.lu.s...
-
visa färre...
Abstract
Ämnesord
Stäng
- Cell surface proteins that bind to the Fc part of Ig are expressed by many strains of group A streptococci, an important human pathogen. Two such bacterial strains, AP4 and AP1, were shown to bind IgA and IgG, respectively, in a temperature-dependent manner. The binding of radiolabeled Ig to the bacterial cells was lower at 37 degrees C than at 22 and 4 degrees C. Similarly, protein Arp, the IgA-binding protein isolated from strain AP4, and protein H, the IgG-binding protein isolated from strain AP1, displayed a strong Ig-binding at 22 degrees C and lower temperatures, and virtually no binding at all at 37 degrees C. The effect was reversible: lowering of the temperature restored the binding and vice versa. A gradual shift between binding and nonbinding took place between 27 and 37 degrees C. Gel chromatography and velocity sedimentation centrifugation showed that protein Arp and protein H appeared as noncovalently associated dimers at 10 and 22 degrees C, and as monomers at 37 degrees C. These results strongly suggest that the dimerization of protein Arp and protein H, rather than the low temperature itself, yielded the strong Ig-binding of the proteins at 10 and 22 degrees C. Indeed, after covalent cross-linking of the dimers at 10 degrees C by incubation with low concentrations of glutaraldehyde, full Ig-binding was achieved even at 37 degrees C. A carboxyl-terminal proteolytic fragment of protein Arp, which completely lacked the IgA-binding capacity at any temperature, showed the same temperature-dependent dimerization as intact protein Arp, suggesting that the Ig-binding part of the protein is not required for dimerization. The implications of these results for the function of Ig-binding group A streptococcal proteins, and their role in the host-parasite relationship are discussed.
Ämnesord
- MEDICIN OCH HÄLSOVETENSKAP -- Medicinska och farmaceutiska grundvetenskaper -- Immunologi inom det medicinska området (hsv//swe)
- MEDICAL AND HEALTH SCIENCES -- Basic Medicine -- Immunology in the medical area (hsv//eng)
Nyckelord
- Bacterial Proteins/metabolism
- Carrier Proteins/metabolism
- Humans
- Immunoglobulin A/metabolism
- Immunoglobulin G/metabolism
- Streptococcus pyogenes/metabolism
- Temperature
Publikations- och innehållstyp
- art (ämneskategori)
- ref (ämneskategori)
Hitta via bibliotek
Till lärosätets databas