In Situ Structure of an Intact Lipopolysaccharide-Bound Bacterial Surface Layer.
Cell
; 180(2): 348-358.e15, 2020 01 23.
Article
en En
| MEDLINE
| ID: mdl-31883796
ABSTRACT
Most bacterial and all archaeal cells are encapsulated by a paracrystalline, protective, and cell-shape-determining proteinaceous surface layer (S-layer). On Gram-negative bacteria, S-layers are anchored to cells via lipopolysaccharide. Here, we report an electron cryomicroscopy structure of the Caulobacter crescentus S-layer bound to the O-antigen of lipopolysaccharide. Using native mass spectrometry and molecular dynamics simulations, we deduce the length of the O-antigen on cells and show how lipopolysaccharide binding and S-layer assembly is regulated by calcium. Finally, we present a near-atomic resolution in situ structure of the complete S-layer using cellular electron cryotomography, showing S-layer arrangement at the tip of the O-antigen. A complete atomic structure of the S-layer shows the power of cellular tomography for in situ structural biology and sheds light on a very abundant class of self-assembling molecules with important roles in prokaryotic physiology with marked potential for synthetic biology and surface-display applications.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Proteínas de la Membrana Bacteriana Externa
/
Glicoproteínas de Membrana
/
Caulobacter crescentus
Idioma:
En
Revista:
Cell
Año:
2020
Tipo del documento:
Article
País de afiliación:
Reino Unido