6P5T

Surface-layer (S-layer) RsaA protein from Caulobacter crescentus bound to strontium and iodide

Summary for 6P5T

• Entry DOI: 10.2210/pdb6p5t/pdb
• Descriptor: S-layer protein, IODIDE ION, STRONTIUM ION, ... (4 entities in total)
• Functional Keywords: surface array, self-assembling, coat protein, rtx motif, membrane protein
• Biological source: Caulobacter vibrioides
• Total number of polymer chains: 6
• Total formula weight: 490317.70

Authors

Chan, A.C.,Herrmann, J.,Smit, J.,Wakatsuki, S.,Murphy, M.E. (deposition date: 2019-05-30, release date: 2020-01-15, Last modification date: 2023-10-11)

Primary citation

Herrmann, J.,Li, P.N.,Jabbarpour, F.,Chan, A.C.K.,Rajkovic, I.,Matsui, T.,Shapiro, L.,Smit, J.,Weiss, T.M.,Murphy, M.E.P.,Wakatsuki, S.
A bacterial surface layer protein exploits multistep crystallization for rapid self-assembly.
Proc.Natl.Acad.Sci.USA, 117:388-394, 2020

PubMed Abstract: Surface layers (S-layers) are crystalline protein coats surrounding microbial cells. S-layer proteins (SLPs) regulate their extracellular self-assembly by crystallizing when exposed to an environmental trigger. However, molecular mechanisms governing rapid protein crystallization in vivo or in vitro are largely unknown. Here, we demonstrate that the SLP readily crystallizes into sheets in vitro via a calcium-triggered multistep assembly pathway. This pathway involves 2 domains serving distinct functions in assembly. The C-terminal crystallization domain forms the physiological 2-dimensional (2D) crystal lattice, but full-length protein crystallizes multiple orders of magnitude faster due to the N-terminal nucleation domain. Observing crystallization using a time course of electron cryo-microscopy (Cryo-EM) imaging reveals a crystalline intermediate wherein N-terminal nucleation domains exhibit motional dynamics with respect to rigid lattice-forming crystallization domains. Dynamic flexibility between the 2 domains rationalizes efficient S-layer crystal nucleation on the curved cellular surface. Rate enhancement of protein crystallization by a discrete nucleation domain may enable engineering of kinetically controllable self-assembling 2D macromolecular nanomaterials.

PubMed: 31848245
DOI: 10.1073/pnas.1909798116

Experimental method

X-RAY DIFFRACTION (2.1 Å)