A Multifunctional ATP-Binding Cassette Transporter System from Vibrio cholerae Transports Vibriobactin and Enterobactin
AUTOR(ES)
Wyckoff, Elizabeth E.
FONTE
American Society for Microbiology
RESUMO
Vibrio cholerae uses the catechol siderophore vibriobactin for iron transport under iron-limiting conditions. We have identified genes for vibriobactin transport and mapped them within the vibriobactin biosynthetic gene cluster. Within this genetic region we have identified four genes, viuP, viuD, viuG and viuC, whose protein products have homology to the periplasmic binding protein, the two integral cytoplasmic membrane proteins, and the ATPase component, respectively, of other iron transport systems. The amino-terminal region of ViuP has homology to a lipoprotein signal sequence, and ViuP could be labeled with [3H]palmitic acid. This suggests that ViuP is a membrane lipoprotein. The ViuPDGC system transports both vibriobactin and enterobactin in Escherichia coli. In the same assay, the E. coli enterobactin transport system, FepBDGC, allowed the utilization of enterobactin but not vibriobactin. Although the entire viuPDGC system could complement mutations in fepB, fepD, fepG, or fepC, only viuC was able to independently complement the corresponding fep mutation. This indicates that these proteins usually function as a complex. V. cholerae strains carrying a mutation in viuP or in viuG were constructed by marker exchange. These mutations reduced, but did not completely eliminate, vibriobactin utilization. This suggests that V. cholerae contains genes in addition to viuPDGC that function in the transport of catechol siderophores.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=94218Documentos Relacionados
- A Novel Bacterial ATP-Binding Cassette Transporter System That Allows Uptake of Macromolecules
- An ATP-Binding Cassette Transporter GhWBC1 from Elongating Cotton Fibers1
- Vanadate-catalyzed photocleavage of the signature motif of an ATP-binding cassette (ABC) transporter
- Characterization of a Sinorhizobium meliloti ATP-Binding Cassette Histidine Transporter Also Involved in Betaine and Proline Uptake
- Pseudoxanthoma elasticum: Mutations in the MRP6 gene encoding a transmembrane ATP-binding cassette (ABC) transporter