Affiliation: | (1) Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093–0116, USA;(2) Integrated Genomics, 2201 W. Campbell Park Dr., Chicago, IL 60612, USA;(3) Integrated Genomics-Moscow, P. O. Box 348, 117333 Moscow , Russia;(4) Institute of Information Transmission Problems, 101447 Moscow , Russia;(5) State Scientific Center GosNIIGenetika, 1st Dorozhny proezd, 1, 113545 Moscow , Russia |
Abstract: | An ABC-type transporter in Escherichia coli that transports both l- and d-methionine, but not other natural amino acids, was identified. This system is the first functionally characterized member of a novel family of bacterial permeases within the ABC superfamily. This family was designated the methionine uptake transporter (MUT) family (TC #3.A.1.23). The proteins that comprise the transporters of this family were analyzed phylogenetically, revealing the probable existence of several sequence-divergent primordial paralogues, no more than two of which have been transmitted to any currently sequenced organism. In addition, MetJ, the pleiotropic methionine repressor protein, was shown to negatively control expression of the operon encoding the ABC-type methionine uptake system. The identification of MetJ binding sites (in gram-negative bacteria) or S-boxes (in gram-positive bacteria) in the promoter regions of several MUT transporter-encoding operons suggests that many MUT family members transport organic sulfur compounds. Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material. |