An Escherichia coli mutant with an amino acid alteration within the signal sequence of outer membrane prolipoprotein.
AUTOR(ES)
Lin, J J
RESUMO
Lipoprotein has been purified from an Escherichia coli strain carrying a mutation in the structural gene for murein lipoprotein (mlpA). Amino acid analysis of the purified mutant lipoprotein indicates that the mutant lipoprotein corresponds to the uncleaved prolipoprotein with a single amino acid replacement of glycine with aspartic acid. Automated Edman degradation has established the precise location of this amino acid substitution to be at the 14th residue of the prolipoprotein. This alteration in the signal sequence of prolipoprotein results in a failure of the mutated prolipoprotein to be processed. Furthermore, the structural alteration in the mutant lipoprotein appears also to have affected its topological localization in the mutant cell. Whereas lipoprotein in the wild-type strain is exclusively located in the outer membrane of the cell envelope, the membrane-bound lipoprotein in this mutant is recovered in both the inner and outer membranes of the cell envelope. The data suggest, however, that proteolytic cleavage of prolipoprotein to form mature lipoprotein is not essential for the translocation and assembly of lipoprotein into the outer membrane.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=336227Documentos Relacionados
- Assembly of outer membrane lipoprotein in an Escherichia coli mutant with a single amino acid replacement within the signal sequence of prolipoprotein.
- Amino acid sequence for the peptide extension on the prolipoprotein of the Escherichia coli outer membrane.
- Amino acid replacement in a mutant lipoprotein of the Escherichia coli outer membrane.
- Amino acid sequence homology among the major outer membrane proteins of Escherichia coli.
- Nucleotide sequence of the Escherichia coli prolipoprotein signal peptidase (lsp) gene.