7e1g

From Proteopedia

Structure of MreB3 from Spiroplasma eriocheiris

Structural highlights

7e1g is a 2 chain structure with sequence from Spiroplasma eriocheiris. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.75Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

A0A0H3XJK5_9MOLU Forms membrane-associated dynamic filaments that are essential for cell shape determination. Acts by regulating cell wall synthesis and cell elongation, and thus cell shape. A feedback loop between cell geometry and MreB localization may maintain elongated cell shape by targeting cell wall growth to regions of negative cell wall curvature.[HAMAP-Rule:MF_02207]

Publication Abstract from PubMed

MreB is a bacterial protein belonging to the actin superfamily. This protein polymerizes into an antiparallel double-stranded filament that determines cell shape by maintaining cell wall synthesis. Spiroplasma eriocheiris, a helical wall-less bacterium, has five MreB homologous (SpeMreB1-5) that probably contribute to swimming motility. Here, we investigated the structure, ATPase activity and polymerization dynamics of SpeMreB3 and SpeMreB5. SpeMreB3 polymerized into a double-stranded filament with possible antiparallel polarity, while SpeMreB5 formed sheets which contained the antiparallel filament, upon nucleotide binding. SpeMreB3 showed slow P(i) release owing to the lack of an amino acid motif conserved in the catalytic centre of MreB family proteins. Our SpeMreB3 crystal structures and analyses of SpeMreB3 and SpeMreB5 variants showed that the amino acid motif probably plays a role in eliminating a nucleophilic water proton during ATP hydrolysis. Sedimentation assays suggest that SpeMreB3 has a lower polymerization activity than SpeMreB5, though their polymerization dynamics are qualitatively similar to those of other actin superfamily proteins, in which pre-ATP hydrolysis and post-P(i) release states are unfavourable for them to remain as filaments.

ATP-dependent polymerization dynamics of bacterial actin proteins involved in Spiroplasma swimming.,Takahashi D, Fujiwara I, Sasajima Y, Narita A, Imada K, Miyata M Open Biol. 2022 Oct;12(10):220083. doi: 10.1098/rsob.220083. Epub 2022 Oct 26. PMID:36285441^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Takahashi D, Fujiwara I, Sasajima Y, Narita A, Imada K, Miyata M. ATP-dependent polymerization dynamics of bacterial actin proteins involved in Spiroplasma swimming. Open Biol. 2022 Oct;12(10):220083. PMID:36285441 doi:10.1098/rsob.220083