Change search
ReferencesLink to record
Permanent link

Direct link
Structural and functional analysis of the N-terminal domain of the Streptococcus gordonii adhesin Sgo0707
Umeå University, Faculty of Medicine, Department of Odontology, Oral Microbiology. (Karina Persson)
Malmö Högskola.
University of Toronto.
University of Toronto.
Show others and affiliations
2013 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 8, no 5, e63768- p.Article in journal (Refereed) Published
Abstract [en]

The commensal Streptococcus gordonii expresses numerous surface adhesins with which it interacts with other microorganisms, host cells and salivary proteins to initiate dental plaque formation. However, this Gram-positive bacterium can also spread to non-oral sites such as the heart valves and cause infective endocarditis. One of its surface adhesins, Sgo0707, is a large protein composed of a non-repetitive N-terminal region followed by several C-terminal repeat domains and a cell wall sorting motif. Here we present the crystal structure of the Sgo0707 N-terminal domains, refined to 2.1 Å resolution. The model consists of two domains, N1 and N2. The largest domain, N1, comprises a putative binding cleft with a single cysteine located in its centre and exhibits an unexpected structural similarity to the variable domains of the streptococcal Antigen I/II adhesins. The N2-domain has an IgG-like fold commonly found among Gram-positive surface adhesins. Binding studies performed on S. gordonii wild-type and a Sgo0707 deficient mutant show that the Sgo0707 adhesin is involved in binding to type-1 collagen and to oral keratinocytes.

Place, publisher, year, edition, pages
Public Library Science , 2013. Vol. 8, no 5, e63768- p.
Keyword [en]
crystal structure, adhesin, collagen
National Category
Structural Biology
Research subject
URN: urn:nbn:se:umu:diva-71563DOI: 10.1371/journal.pone.0063768ISI: 000319107900058OAI: diva2:624966
Swedish Research Council, 2011-4186
Available from: 2013-06-03 Created: 2013-06-03 Last updated: 2013-08-13Bibliographically approved
In thesis
1. Structural and functional studies of streptococcal surface adhesins
Open this publication in new window or tab >>Structural and functional studies of streptococcal surface adhesins
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The oral cavity is home to an array of microorganisms that are associated with dental plaque. Some Gram-positive bacteria are common inhabitants of the oral cavity and in order to colonize such a unique environment adhesion becomes essential and is accomplish by adhesins expressed on the bacterial surface. Adhesins can interact with host molecules or with structures on the resident oral microbial flora. Members of the antigen I/II (AgI/II) protein family are commonly found on the surface of oral streptococci and have the unique feature that their putative adhesin domain is located in the centre of the primary sequence. Crystal structures representing parts of the C-terminal domains from two AgI/II members, SpaP from Streptococcus mutans and AspA from Streptococcus pyogenes, were determined to 2.2 and 1.8 Å resolution respectively. The structures are very similar and consist of two domains with DEv-IgG folds. The proteins are stabilized by intramolecular isopeptide bonds and tightly coordinated metal ions.

Another group of surface proteins is the microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) that have their putative adhesin domain in the N-terminal, presented on a stalk formed by multiples of repeated C-terminal domains. Sgo0707 from Streptococcus gordonii is an example of this group of proteins and its N-terminal domain was determined to 2.1 Å resolution. The structure consists of two domains, N1 and N2, both of which adopt β-sandwiches. In the Sgo0707 structure no isopeptide bonds or metal ions were detected. A putative binding cleft is present in the N1 domain. Functional studies revealed collagen type-1 and keratinocytes as possible binding partners.

In order to further characterize the AgI/II protein AspA from S. pyogenes a long form of the protein, AspA-AVPC, was expressed and purified. During the purification process it was observed that the protein fragmented into two major parts. This process could be inhibited by the addition of 0.5 mM EDTA during protein purification.

In conclusion, these studies have resulted in adding to the knowledge of protein structures and function of streptococcal surface proteins.

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2013. 41 p.
Umeå University odontological dissertations, ISSN 0345-7532 ; 126
National Category
Structural Biology
urn:nbn:se:umu:diva-78920 (URN)978-7459-689-2 (ISBN)
Public defence
2013-09-12, Sal 9D, Tandläkarhögskolan 9 tr, Norrlands universitetssjukhus, Umeå, 10:00 (English)
Available from: 2013-08-15 Created: 2013-07-25 Last updated: 2013-09-27Bibliographically approved

Open Access in DiVA

Structural and functional analysis of the N-terminal domain of the Streptococcus gordonii adhesin Sgo0707(4591 kB)343 downloads
File information
File name FULLTEXT02.pdfFile size 4591 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Nylander, ÅsaPersson, Karina
By organisation
Oral MicrobiologyDepartment of Chemistry
In the same journal
Structural Biology

Search outside of DiVA

GoogleGoogle Scholar
Total: 343 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 142 hits
ReferencesLink to record
Permanent link

Direct link