Specificity and topology of the Escherichia coli xanthosine permease, a representative of the NHS subfamily of the major facilitator superfamily.
نویسندگان
چکیده
The specificity of XapB permease was compared with that of the known nucleoside transporters NupG and NupC. XapB-mediated xanthosine uptake is abolished by 2,4-dinitrophenol and exhibits saturation kinetics with an apparent K(m) of 136 microM. A 12-transmembrane-segment model was confirmed by translational fusions to alkaline phosphatase and the alpha fragment of beta-galactosidase.
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عنوان ژورنال:
- Journal of bacteriology
دوره 183 16 شماره
صفحات -
تاریخ انتشار 2001