Publication Date:
2010-02-12
Description:
An MsbA deletion mutant ΔC21 that lacks the two C-terminal α-helices was expressed inEscherichia colistrain C41 and purified by metal-affinity and gel-filtration chromatography. Purified ΔC21 retained 26% of the activity of the wild-type ATPase and had a similar binding affinity to fluorescent nucleotide derivatives. Although crystals of wild-type MsbA complexed with adenosine 5′-(β,γ-imido)triphosphate could not be obtained, crystals of ΔC21 that diffracted to 4.5 Å resolution were obtained. The preliminary ΔC21 structure had the outward-facing conformation, in contrast to the previously reportedE. coliMsbA structure. This result suggests that deletion of the C-terminal α-helices may play a role in facilitating the outward-facing nucleotide-bound crystal structure of EcMsbA.
Print ISSN:
0907-4449
Electronic ISSN:
1399-0047
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
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