Transposon Tn10-dependent expression of the lamB gene in Escherichia coli.
AUTOR(ES)
Brass, J M
RESUMO
Among Tn10 insertions isolated in or near the malB region of Escherichia coli, one (zjb-729::Tn10) mapped between malK and lamB or late in malK and allowed MalT-independent expression of lamB. Tn10-dependent expression of a lamB-lacZ protein fusion was 25% of the expression of the fusion from the malK-lamB operon promoter in malTc constitutive strains. The maltoporin content of a strain carrying this Tn10 was about 20% that of a malTc malB+ strain. Transport of maltose at concentrations of below 10(-6) M was reduced about threefold. When maltoporin was present at about 50% of the level of malTc malB+ strains, maltose transport was largely restored. We conclude that maltoporin is not rate limiting for maltose transport in wild-type cells but becomes rate limiting when the ratio of maltoporin to other maltose transport components is reduced more than twofold.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=215597Documentos Relacionados
- Interaction of bacteriophage K10 with its receptor, the lamB protein of Escherichia coli.
- Mutations that alter the transport function of the LamB protein in Escherichia coli.
- Signal sequence processing is required for the assembly of LamB trimers in the outer membrane of Escherichia coli.
- Tn10 insertions in the pfkB region of Escherichia coli.
- Stoichiometry of maltodextrin-binding sites in LamB, an outer membrane protein from Escherichia coli.
