Hydrophobic residues of the autotransporter EspP linker domain are important for outer membrane translocation of its passenger.
J Biol Chem
; 279(30): 31495-504, 2004 Jul 23.
Article
en En
| MEDLINE
| ID: mdl-15151995
ABSTRACT
The autotransporter family of proteins is an important class of Gram-negative secreted virulence factors. Their secretion mechanism comprises entry to the periplasm via the Sec apparatus, followed by formation of an outer membrane beta barrel, which allows the N-terminal passenger domain to pass to the extracellular space. Several groups have identified a region immediately upstream of the beta domain that is important for outer membrane translocation, the so-called linker region. Here we characterize this region in EspP, a prototype of the serine protease autotransporters of enterobacteriaceae. We hypothesized that the folding of this region would be important in the outer membrane translocation process. We tested this hypothesis using a mutagenesis approach in conjunction with a series of nested deletions and found that in the absence of a complete passenger, mutations to the C-terminal helix, but not the upstream linker, significantly decrease secretion efficiency. However, in the presence of the passenger mutations to the amino-terminal region of the linker decrease secretion efficiency. Moreover, amino acids of hydrophobic character play a crucial role in linker function, suggesting the existence of a hydrophobic core or hydrophobic interaction necessary for outer membrane translocation of autotransporter proteins.
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Banco de datos:
MEDLINE
Asunto principal:
Serina Endopeptidasas
/
Proteínas de Escherichia coli
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
J Biol Chem
Año:
2004
Tipo del documento:
Article
País de afiliación:
Estados Unidos