SASDAC6: PsrP functional binding region (Functional binding region (187-38...

Basic information

• Entry: Database: SASBDB / ID: SASDAC6

Sample

PsrP functional binding region

• Functional binding region (187-385) of the pneumococcal serine-rich repeat protein (protein), PsrP BR(187-385), Streptococcus pneumoniae

Function / homology

Function:

Gram-positive-bacterium-type cell wall / symbiont-mediated perturbation of host defense response / single-species biofilm formation / cell adhesion / cell surface / DNA binding / extracellular region

Domain/homology:

Serine-rich repeat adhesion glycoprotein / LPXTG cell wall anchor motif / Gram-positive cocci surface proteins LPxTG motif profile. / LPXTG cell wall anchor domain

Component:

Pneumococcal serine-rich repeat protein

• Biological species: Streptococcus pneumoniae (bacteria)
• Citation: Journal: Sci Rep / Year: 2016; Title: The BR domain of PsrP interacts with extracellular DNA to promote bacterial aggregation; structural insights into pneumococcal biofilm formation.; Authors: Tim Schulte / Cecilia Mikaelsson / Audrey Beaussart / Alexey Kikhney / Maya Deshmukh / Sebastian Wolniak / Anuj Pathak / Christine Ebel / Jonas Löfling / Federico Fogolari / Birgitta Henriques-Normark / Yves F Dufrêne / Dmitri Svergun / Per-Åke Nygren / Adnane Achour / ; Abstract: The major human pathogen Streptococcus pneumoniae is a leading cause of disease and death worldwide. Pneumococcal biofilm formation within the nasopharynx leads to long-term colonization and persistence within the host. We have previously demonstrated that the capsular surface-associated pneumococcal serine rich repeat protein (PsrP), key factor for biofilm formation, binds to keratin-10 (KRT10) through its microbial surface component recognizing adhesive matrix molecule (MSCRAMM)-related globular binding region domain (BR187-385). Here, we show that BR187-385 also binds to DNA, as demonstrated by electrophoretic mobility shift assays and size exclusion chromatography. Further, heterologous expression of BR187-378 or the longer BR120-378 construct on the surface of a Gram-positive model host bacterium resulted in the formation of cellular aggregates that was significantly enhanced in the presence of DNA. Crystal structure analyses revealed the formation of BR187-385 homo-dimers via an intermolecular β-sheet, resulting in a positively charged concave surface, shaped to accommodate the acidic helical DNA structure. Furthermore, small angle X-ray scattering and circular dichroism studies indicate that the aggregate-enhancing N-terminal region of BR120-166 adopts an extended, non-globular structure. Altogether, our results suggest that PsrP adheres to extracellular DNA in the biofilm matrix and thus promotes pneumococcal biofilm formation.

Contact author

• Al Kikhney (EMBL-Hamburg, European Molecular Biology Laboratory (EMBL) - Hamburg outstation, Notkestraße 85, Geb. 25A, 22607 Hamburg, Deutschland, Germany)

Models

• Model #565: ; Type: mix / Software: EOM (1.3) / Radius of dummy atoms: 1.90 A / Chi-square value: 0.974169; Search similar-shape structures of this assembly by Omokage search (details)
• Model #566: ; Type: mix / Software: EOM (1.4) / Radius of dummy atoms: 1.90 A / Chi-square value: 0.974169; Search similar-shape structures of this assembly by Omokage search (details)

Sample

• Sample: Name: PsrP functional binding region / Specimen concentration: 2.9 mg/ml
• Buffer: Name: PBS / pH: 7.4 / Comment: Phosphate buffered saline / Composition: Glycerol 5.000 %

Entity #37

Name: PsrP BR(187-385) / Type: protein
Description: Functional binding region (187-385) of the pneumococcal serine-rich repeat protein
Formula weight: 22.12 / Num. of mol.: 1 / Source: Streptococcus pneumoniae / References: UniProt: A0A0H2URK1
Sequence:

HHHHHHSGNT IVNGAPAINA SLNIAKSETK VYTGEGVDSV YRVPIYYKLK VTNDGSKLTF TYTVTYVNPK TNDLGNISSM RPGYSIYNSG TSTQTMLTLG SDLGKPSGVK NYITDKNGRQ VLSYNTSTMT TQGSGYTWGN GAQMNGFFAK KGYGLTSSWT VPITGTDTSF TFTPYAARTD RIGINYFNGG GKVVESSTTS QSLSQ

Experimental information

• Beam: Instrument name: ESRF BM29 / City: Grenoble / 国: France / Type of source: X-ray synchrotron / Wavelength: 0.09919 Å / Dist. spec. to detc.: 2.43 mm
• Detector: Name: Pilatus 1M

Scan

Title: PsrP functional binding region / Measurement date: Feb 27, 2013 / Storage temperature: 20 °C / Cell temperature: 20 °C / Exposure time: 1 sec. / Number of frames: 10 / Unit: 1/nm /

	Min	Max
Q	0.0716	4.4209

Distance distribution function P(R)

Sofotware P(R): GNOM 4.6 / Number of points: 429 /

	Min	Max
Q	0.2387	3.952
P(R) point	49	477
R	0	7.8

Result

Type of curve: single_conc / Standard: BSA

	Experimental	Standard	Porod
MW	18 kDa	17 kDa	23.6 kDa
Volume	-	-	37.7 nm3

	P(R)	Guinier
Forward scattering, I0	18.64	18.511
Radius of gyration, Rg	2.11 nm	2.039 nm

	Min	Max
D	-	7.8
Guinier point	40	108