SASDAB4: Truncated GbpA (GbpA_truncated)

Basic information

• Entry: Database: SASBDB / ID: SASDAB4

Sample

Truncated GbpA

• Truncated GbpA (protein), GbpA_truncated, Vibrio cholerae

• Biological species: Vibrio cholerae (bacteria)
• Citation: Journal: PLoS Pathog / Year: 2012; Title: The Vibrio cholerae colonization factor GbpA possesses a modular structure that governs binding to different host surfaces.; Authors: Edmond Wong / Gustav Vaaje-Kolstad / Avishek Ghosh / Ramon Hurtado-Guerrero / Peter V Konarev / Adel F M Ibrahim / Dmitri I Svergun / Vincent G H Eijsink / Nabendu S Chatterjee / Daan M F van Aalten / ; Abstract: Vibrio cholerae is a bacterial pathogen that colonizes the chitinous exoskeleton of zooplankton as well as the human gastrointestinal tract. Colonization of these different niches involves an N-acetylglucosamine binding protein (GbpA) that has been reported to mediate bacterial attachment to both marine chitin and mammalian intestinal mucin through an unknown molecular mechanism. We report structural studies that reveal that GbpA possesses an unusual, elongated, four-domain structure, with domains 1 and 4 showing structural homology to chitin binding domains. A glycan screen revealed that GbpA binds to GlcNAc oligosaccharides. Structure-guided GbpA truncation mutants show that domains 1 and 4 of GbpA interact with chitin in vitro, whereas in vivo complementation studies reveal that domain 1 is also crucial for mucin binding and intestinal colonization. Bacterial binding studies show that domains 2 and 3 bind to the V. cholerae surface. Finally, mouse virulence assays show that only the first three domains of GbpA are required for colonization. These results explain how GbpA provides structural/functional modular interactions between V. cholerae, intestinal epithelium and chitinous exoskeletons.

Contact author

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

Models

• Model #53: ; Type: dummy / Software: Gasbor / Chi-square value: 2.6569; Search similar-shape structures of this assembly by Omokage search (details)
• Model #54: ; Type: atomic / Software: Sasref / Chi-square value: 3.794704; Search similar-shape structures of this assembly by Omokage search (details)

Sample

• Sample: Name: Truncated GbpA / Sample MW: 44 kDa / Specimen concentration: 2 mg/ml
• Buffer: Name: 25 mM Tris/HCl / pH: 7.5 / Composition: NaCl 150.000 mM

Entity #51

Name: GbpA_truncated / Type: protein / Description: Truncated GbpA / Formula weight: 44 / Num. of mol.: 1 / Source: Vibrio cholerae
Sequence:

HGYVSAVENG VAEGRVTLCK FAANGTGEKN THCGAIQYEP QSVEGPDGFP VTGPRDGKIA SAESALAAAL DEQTADRWVK RPIQAGPQTF EWTFTANHVT KDWKYYITKP NWNPNQPLSR DAFDLNPFCV VEGNMVQPPK RVSHECIVPE REGYQVILAV WDVGDTAASF YNVIDVKFDG NGPVLPDWNP AGQIIPSMDL SIGDTVYTRV FDNDGENPAY RTELKIDSET LTKANQWSYA LATKINQTQK QQRAGQLNGD QFVPVYGTNP IYLKEGSGLK SVEIGYQIEA PQPEYSLTVS GLAKEYEIGE QPIQLDLTLE AQGEMSAELT VYNHHQKPLA SWSQAMTDGE LKSITLELSE AKAGHHMLVS RIKDRDGNLQ DQQTLDFMLV EPQTPPTPGD YDFVFPNGLK EYV

Experimental information

• Beam: Instrument name: DORIS III X33 / City: Hamburg / 国: Germany / Type of source: X-ray synchrotron
• Detector: Name: MAR 345 Image Plate

Scan

Title: Truncated GbpA / Measurement date: Oct 16, 2007 / Storage temperature: 10 °C / Cell temperature: 10 °C / Exposure time: 120 sec. / Number of frames: 1 / Unit: 1/nm /

	Min	Max
Q	0.1771	4.908

Distance distribution function P(R)

Sofotware P(R): GNOM 4.5a / Number of points: 512 /

	Min	Max
Q	0.1771	4.908
P(R) point	1	512
R	0	12.5

Result

Type of curve: single_conc /

	Experimental	Porod
MW	46 kDa	-
Volume	-	80 nm3

	P(R)	Guinier
Forward scattering, I0	146	169
Radius of gyration, Rg	3.65 nm	3.6 nm

	Min	Max
D	-	12.5
Guinier point	1	14