SASDAQ5: Lumazine Synthase

Basic information

• Entry: Database: SASBDB / ID: SASDAQ5

Sample

Lumazine Synthase

• Lumazine Synthase (protein), Lumazine Synthase, B. subtilis

• Biological species: B. subtilis
• Citation: Journal: J Mol Biol / Year: 2006; Title: Multiple assembly states of lumazine synthase: a model relating catalytic function and molecular assembly.; Authors: Xiaofeng Zhang / Petr V Konarev / Maxim V Petoukhov / Dmitri I Svergun / Li Xing / R Holland Cheng / Ilka Haase / Markus Fischer / Adelbert Bacher / Rudolf Ladenstein / Winfried Meining / ; Abstract: Lumazine synthases have been observed in the form of pentamers, dimers of pentamers, icosahedral capsids consisting of 60 subunits and larger capsids with unknown molecular structure. Here we describe the analysis of the assembly of native and mutant forms of lumazine synthases from Bacillus subtilis and Aquifex aeolicus at various pH values and in the presence of different buffers using small angle X-ray scattering and electron microscopy. Both wild-type lumazine synthases are able to form capsids with a diameter of roughly 160 A and larger capsids with diameters of around 300 A. The relative abundance of smaller and larger capsids is strongly dependent on buffer and pH. Both forms can co-exist and are in some cases accompanied by other incomplete or deformed capsids. Several mutants of the B. subtilis lumazine synthase, in which residues in or close to the active site were replaced, as well as an insertion mutant of A. aeolicus lumazine synthase form partially or exclusively larger capsids with a diameter of about 300 A. The mutations also reduce or inhibit enzymatic activity, suggesting that the catalytic function of the enzyme is tightly correlated with its quaternary structure. The data show that multiple assembly forms are a general feature of lumazine synthases.

Contact author

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

Models

• Model #135: ; Type: dummy / Software: dammin / Radius of dummy atoms: 1.90 A / Symmetry: Icosohedra / Chi-square value: 3942.960849; Search similar-shape structures of this assembly by Omokage search (details)

Sample

• Sample: Name: Lumazine Synthase / Sample MW: 960 kDa
• Buffer: Name: Borate buffer / pH: 7

Entity #98

Name: Lumazine Synthase / Type: protein / Description: Lumazine Synthase / Formula weight: 16.29 / Source: B. subtilis
Sequence:

MNIIQGNLVG TGLKIGIVVG RFNDFITSKL LSGAEDALLR HGVDTNDIDV AWVPGAFEIP FAAKKMAETK KYDAIITLGT VIRGATTHYD YVCNEAAKGI AQAANTTGVP VIFGIVTTEN IEQAIERAGT KAGNKGVDCA VSAIEMANLN RSFE

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: Lumazine Syntahse in Borate Buffer / Measurement date: Nov 25, 2004 / Storage temperature: 15 °C / Cell temperature: 15 °C / Exposure time: 120 sec. / Number of frames: 2 / Unit: 1/nm /

	Min	Max
Q	0.1056	3.328

Distance distribution function P(R)

Sofotware P(R): GNOM 4.5a / Number of points: 392 /

	Min	Max
Q	0.1858	3.326
P(R) point	30	421
R	0	15.5

Result

D max: 15.5 / Type of curve: single_conc /

	Experimental	Porod
MW	960 kDa	-
Volume	-	1450 nm3

	P(R)	Guinier
Forward scattering, I0	581400	607904
Radius of gyration, Rg	6.18 nm	6.65 nm