Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

Identification of the Autochaperone Domain in the Type Va Secretion System (T5aSS): Prevalent Feature of Autotransporters with a β-Helical Passenger

Abstract : Autotransporters (ATs) belong to a family of modular proteins secreted by the Type V, subtype a, secretion system (T5aSS) and considered as an important source of virulence factors in lipopolysaccharidic diderm bacteria (archetypical Gram-negative bacteria). While exported by the Sec pathway, the ATs are further secreted across the outer membrane via their own C-terminal translocator forming a b-barrel, through which the rest of the protein, namely the passenger, can pass. In several ATs, an autochaperone domain (AC) present at the C-terminal region of the passenger and upstream of the translocator was demonstrated as strictly required for proper secretion and folding. However, considering it was functionally characterised and identified only in a handful of ATs, wariness recently fells on the commonality and conservation of this structural element in the T5aSS. To circumvent the issue of sequence divergence and taking advantage of the resolved three-dimensional structure of some ACs, identification of this domain was performed following structural alignment among all AT passengers experimentally resolved by crystallography before searching in a dataset of 1523 ATs. While demonstrating that the AC is indeed a conserved structure found in numerous ATs, phylogenetic analysis further revealed a distribution into deeply rooted branches, from which emerge 20 main clusters. Sequence analysis revealed that an AC could be identified in the large majority of SAATs (self-associating ATs) but not in any LEATs (lipase/esterase ATs) nor in some PATs (protease autotransporters) and PHATs (phosphatase/hydrolase ATs). Structural analysis indicated that an AC was present in passengers exhibiting single-stranded right-handed parallel b-helix, whatever the type of b-solenoid, but not with a-helical globular fold. From this investigation, the AC of type 1 appears as a prevalent and conserved structural element exclusively associated to b-helical AT passenger and should promote further studies about the protein secretion and folding via the T5aSS, especially toward a-helical AT passengers.
Type de document :
Article dans une revue
Liste complète des métadonnées

Littérature citée [82 références]  Voir  Masquer  Télécharger

https://hal.umontpellier.fr/hal-01968806
Contributeur : Yvan Boublik <>
Soumis le : mardi 26 mai 2020 - 01:34:06
Dernière modification le : mardi 22 septembre 2020 - 09:04:03

Fichier

2018_Rojas-Lopez_Front_Microbi...
Fichiers éditeurs autorisés sur une archive ouverte

Licence


Distributed under a Creative Commons Paternité 4.0 International License

Identifiants

Citation

Maricarmen Rojas-Lopez, Mohamed Zorgani, Lawrence Kelley, Xavier Bailly, Andrey Kajava, et al.. Identification of the Autochaperone Domain in the Type Va Secretion System (T5aSS): Prevalent Feature of Autotransporters with a β-Helical Passenger. Frontiers in Microbiology, Frontiers Media, 2018, 8, ⟨10.3389/fmicb.2017.02607⟩. ⟨hal-01968806⟩

Partager

Métriques

Consultations de la notice

368

Téléchargements de fichiers

129