ISSN:
1399-0047
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The primary receptor (potD, Mr = 39 000) of the polyamine transport system in Escherichia coli has been crystallized by the vapor-diffusion method. Two crystal forms were obtained in the presence of spermidine, and were examined by X-ray analysis. Form I crystals, which diffract to 2.5 Å resolution, belong to the space group P21, with unit-cell dimensions a = 145.3, b = 69.1, c = 72.5 Å and β = 107.6°. Four molecules are contained in an asymmetric unit. These form two dimers that are related to each other by a local translation of about half of the unit cell along the a axis. The two protein molecules in each dimer are similarly related by a local dyad. Form II crystals diffract to 1.8 Å resolution and belong to the space group I41, with unit-cell dimensions a = b = 130.3 and c = 38.7 Å. They contain one molecule per asymmetric unit.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0907444995011498
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