Binding protein-dependent transport systems

Abstract

Bacterial binding protein-dependent transport systems are the best characterized members of a superfamily of transporters which are structurally, functionally, and evolutionary related to each other. These transporters are not only found in bacteria but also in yeasts, plants, and animals including man, and include both import and export systems. Although any single system is relatively specific, different systems handle very different substrates which can be inorganic ions, amino acids, sugars, large polysaccharides, or even proteins. Some are of considerable medical importance, including Mdr, the protein responsible for multidrug resistance in human tumors, and the product of the cystic fibrosis locus. In this article we review the current state of knowledge on the structure and function of the protein components of these transporters, the mechanism by which transport is mediated, and the role of ATP in the transport process.

Repression of the glucose-inducible outer-membrane protein OprB during utilization of aromatic compounds and organic acids in Pseudomonas putida CSV86

“…Once the solute is transported across the outer membrane, solute-specific periplasmic protein can selectively bind to the solute and present it to the ABC transporter system located in the inner membrane for inward transport (Higgins et al, 1990). In Pseudomonas, the inner membrane glucose transport component has not yet been identified; however, a specific transport component has been studied in detail for maltose uptake in E. coli (Chen et al, 2001).…”

ATP and GTP as alternative energy sources for vinblastine transport by P‐170 in KB‐V1 plasma membrane vesicles

“…Previously reported data with this system showed a requirement for ATP, and osmotic sensitivity of the uptake process [7,8]. The population of purified vesicles used to demonstrate transport consists of rightside-out and inverted (inside.out) vesicles.…”

Involvement of the C-terminal Domain of an ATP-binding Subunit in the Regulation of the ABC-type Nitrate/Nitrite Transporter of the Cyanobacterium Synechococcus sp. Strain PCC 7942

“…The product of the nrtA gene is a 45-kDa cytoplasmic membrane protein (3), which has been shown to be a nitrate/nitrite-binding lipoprotein (18). The deduced NrtB protein has structural similarities to the integral membrane components of the ABC (ATP-binding cassette) transporters, and the deduced NrtC and NrtD proteins have the sequences typical of the ATP-binding components of the ABC transporters (5), showing that the cyanobacterial nitrate/ nitrite transporter belongs to the superfamily of ABC transporters (19) or traffic ATPases (20). NrtC is unique among the ATP-binding subunits of the ABC transporters in that it consists of two distinct domains, one of which (amino acids 1-254) is strongly similar to NrtD and the ATP-binding subunits of other ABC transporters, whereas the other (amino acids 279 -659) is 30% identical in amino acid sequence to NrtA (5).…”