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A second IgG-binding protein in Staphylococcus aureus.

Lihong Zhang·Karin Jacobsson·Jozsef Vasi·Martin Lindberg·Lars Frykberg
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Abstract

Most strains of Staphylococcus aureus express IgG-binding activity and this binding has been considered to be solely mediated by protein A. However, the existence of a second gene in S. aureus strain 8325-4 encoding an IgG-binding polypeptide was recently reported. This novel IgG-binding polypeptide was found after panning a shotgun phage display library, made from chromosomal DNA, against immobilized human IgG. The complete gene (sbi) encoding this novel IgG-binding protein, denoted protein Sbi, has now been cloned and sequenced. Analysis of other S. aureus strains showed that this gene is not unique for strain 8325-4. The protein consists of 436 amino acids and exhibits an immunoglobulin-binding specificity similar to protein A. Furthermore, it is shown that Sbi is highly expressed in strain Newman 4, which shows that IgG-binding activity in S. aureus can be mediated by proteins other than protein A.

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Bacterial Outer Membrane ProteinsBacterial ProteinsBase SequenceBlotting, SouthernBlotting, WesternCarrier ProteinsElectrophoresis, Polyacrylamide GelGenes, BacterialMolecular Sequence DataSequence AlignmentStaphylococcus aureusJournal ArticleResearch Support, Non-U.S. Gov't

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Lihong Zhang, Karin Jacobsson, Jozsef Vasi, Martin Lindberg, Lars Frykberg. 1998. A second IgG-binding protein in Staphylococcus aureus.. https://doi.org/10.1099/00221287-144-4-985

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