A new class of hybrid secretion system is employed in Pseudomonas amyloid biogenesis.
Nat Commun
; 8(1): 263, 2017 08 15.
Article
em En
| MEDLINE
| ID: mdl-28811582
ABSTRACT
Gram-negative bacteria possess specialised biogenesis machineries that facilitate the export of amyloid subunits for construction of a biofilm matrix. The secretion of bacterial functional amyloid requires a bespoke outer-membrane protein channel through which unfolded amyloid substrates are translocated. Here, we combine X-ray crystallography, native mass spectrometry, single-channel electrical recording, molecular simulations and circular dichroism measurements to provide high-resolution structural insight into the functional amyloid transporter from Pseudomonas, FapF. FapF forms a trimer of gated ß-barrel channels in which opening is regulated by a helical plug connected to an extended coil-coiled platform spanning the bacterial periplasm. Although FapF represents a unique type of secretion system, it shares mechanistic features with a diverse range of peptide translocation systems. Our findings highlight alternative strategies for handling and export of amyloid protein sequences.Gram-negative bacteria assemble biofilms from amyloid fibres, which translocate across the outer membrane as unfolded amyloid precursors through a secretion system. Here, the authors characterise the structural details of the amyloid transporter FapF in Pseudomonas.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pseudomonas
/
Proteínas de Bactérias
/
Sistemas de Secreção Bacterianos
/
Amiloide
Idioma:
En
Revista:
Nat Commun
Assunto da revista:
BIOLOGIA
/
CIENCIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Reino Unido