SASDAE6: PsrP functional binding region (Functional binding region (120-39...

Basic information

• Entry: Database: SASBDB / ID: SASDAE6

Sample

PsrP functional binding region

• Functional binding region (120-395) of the pneumococcal serine-rich repeat protein (protein), PsrP BR*(120-395), 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 #563: ; Type: mix / Software: EOM (1.3) / Radius of dummy atoms: 1.90 A / Chi-square value: 2.778889; Search similar-shape structures of this assembly by Omokage search (details)
• Model #564: ; Type: mix / Software: EOM (1.3) / Radius of dummy atoms: 1.90 A / Chi-square value: 2.778889; Search similar-shape structures of this assembly by Omokage search (details)

Sample

• Sample: Name: PsrP functional binding region / Specimen concentration: 0.32-3.00
• Buffer: Name: PBS / pH: 7.4 / Comment: Phosphate buffered saline / Composition: Glycerol 5.000 %

Entity #122

Name: PsrP BR*(120-395) / Type: protein
Description: Functional binding region (120-395) of the pneumococcal serine-rich repeat protein
Formula weight: 30.3 / Num. of mol.: 1 / Source: Streptococcus pneumoniae / References: UniProt: A0A0H2URK1
Sequence:

HHHHHHSSTV VGSQTAAATE ATAKKVEEDR KKPASDYVAS VTNVNLQSYA KRRKRSVDSI EQLLASIKNA AVFSGNTIVN GAPAINASLN IAKSETKVYT GEGVDSVYRV PIYYKLKVTN DGSKLTFTYT VTYVNPKTND LGNISSMRPG YSIYNSGTST QTMLTLGSDL GKPSGVKNYI TDKNGRQVLS YNTSTMTTQG SGYTWGNGAQ MNGFFAKKGY GLTSSWTVPI TGTDTSFTFT PYAARTDRIG INYFNGGGKV VESSTTSQSL SQSKSLSVSA SQ

Experimental information

• Beam: Instrument name: ESRF BM29 / City: Grenoble / 国: France / Type of source: X-ray synchrotronSynchrotron / Wavelength: 0.93 Å / Dist. spec. to detc.: 2.43 mm
• Detector: Name: Pilatus 1M

Scan

Title: PsrP functional binding region (longer) / 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	0.0499	4.282

Distance distribution function P(R)

Sofotware P(R): GNOM 4.6 / Number of points: 302 /

	Min	Max
Q	0.1129	2.724
P(R) point	20	321
R	0	12

Result

Type of curve: extrapolated / Standard: BSA

	Experimental	Standard	Porod	Estimated
MW	28.7 kDa	20 kDa	25.7 kDa	-
Volume	-	-	41.1 nm3	57

	P(R)	Guinier
Forward scattering, I0	22.08	21.83
Radius of gyration, Rg	3.13 nm	2.935 nm

	Min	Max
D	-	12.5
Guinier point	16	86