8P3O

Full-length bacterial polysaccharide co-polymerase WzzE mutant R267A from E. coli. C4 symmetry

Summary for 8P3O

• Entry DOI: 10.2210/pdb8p3o/pdb
• Related: 8BHW 8P3P
• EMDB information: 16071 16072 16073 17387 17388 17389 17390
• Descriptor: ECA polysaccharide chain length modulation protein (1 entity in total)
• Functional Keywords: complex, lipopolysaccharide, bacterial polysaccharide co-polymerase, membrane protein
• Biological source: Escherichia coli K-12
• Total number of polymer chains: 8
• Total formula weight: 330599.25

Authors

Wiseman, B.,Hogbom, M. (deposition date: 2023-05-18, release date: 2023-07-26, Last modification date: 2024-07-24)

Primary citation

Wiseman, B.,Widmalm, G.,Hogbom, M.
Alternating L4 loop architecture of the bacterial polysaccharide co-polymerase WzzE.
Commun Biol, 6:802-802, 2023

PubMed Abstract: Lipopolysaccharides such as the enterobacterial common antigen are important components of the enterobacterial cell envelope that act as a protective barrier against the environment and are often polymerized by the inner membrane bound Wzy-dependent pathway. By employing cryo-electron microscopy we show that WzzE, the co-polymerase component of this pathway that is responsible for the length modulation of the enterobacterial common antigen, is octameric with alternating up-down conformations of its L4 loops. The alternating up-down nature of these essential loops, located at the top of the periplasmic bell, are modulated by clashing helical faces between adjacent protomers that flank the L4 loops around the octameric periplasmic bell. This alternating arrangement and a highly negatively charged binding face create a dynamic environment in which the polysaccharide chain is extended, and suggest a ratchet-type mechanism for polysaccharide elongation.

PubMed: 37532793
DOI: 10.1038/s42003-023-05157-7

Experimental method

ELECTRON MICROSCOPY (2.9 Å)