ISSN:
1399-0047
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Mirabilis anti-viral protein (MAP) is a ribosome-inactivating protein from Mirabilis jalapa L. Since MAP is effective over a broad spectrum of species, the protein is difficult to express in heterologous hosts such as Escherichia coli. Recently, we obtained a MAP mutant, Y72F which exhibits a lower (1/100) activity against E. coli ribosomes while retaining almost full activity against mammalian cells [Habuka, Miyano, Kataoka, Tsuge & Noma (1992). J. Biol. Chem. 267, 7758–7760]. For the crystallographic studies, the Y72F MAP expression vector with an OmpA leading sequence was constructed and expressed in E. coli. The Y72F MAP mutant was then isolated and purified from the cell culture medium. Crystals were grown using the crystallization conditions for the native MAP crystals [Miyano et al. (1992). J. Mol. Biol. 226, 281–283]: 50% ammonium sulfate containing 50 mM ammonium citrate and 2 mM adenine sulfate, pH 5.4. The crystals belong to space group P3121 (or P3221) with a = b = 104.1 and c = 134.3 Å. The crystals are isomorphous with the wild-type crystals but diffract to higher resolution. Imaging-plate photographs of the Y72F mutant showed sharp intense spots without the streaking observed in the native crystals.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0907444994002325
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