PDBsum entry 2lfv

Cell cycle

PDB id: 2lfv

Contents

Protein chain

106 a.a.

PDB id:

2lfv

Name:

Cell cycle

Title:

Solution structure of the spor domain from e. Coli damx

Structure:

Protein damx. Chain: a. Fragment: sequence database residures 338-428. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 83333. Strain: k12 mg1655. Gene: b3388, damx, yhfb. Expressed in: escherichia coli. Expression_system_taxid: 469008.

NMR struc:

25 models

Authors:

K.B.Williams,S.J.R.Arends,D.L.Popham,C.A.Fowler,D.S.Weiss

Key ref:

K.B.Williams et al. (2013). Nuclear magnetic resonance solution structure of the peptidoglycan-binding SPOR domain from Escherichia coli DamX: insights into septal localization. Biochemistry, 52, 627-639. PubMed id: 23290046

Date:

15-Jul-11 Release date: 18-Jul-12

Protein chain

P11557  (DAMX_ECOLI) -  Cell division protein DamX from Escherichia coli (strain K12)

Seq: 428 a.a.

Struc: 106 a.a.*

* PDB and UniProt seqs differ at 14 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.?

Biochemistry 52:627-639 (2013)

PubMed id: 23290046

Nuclear magnetic resonance solution structure of the peptidoglycan-binding SPOR domain from Escherichia coli DamX: insights into septal localization.

K.B.Williams, A.Yahashiri, S.J.Arends, D.L.Popham, C.A.Fowler, D.S.Weiss.

ABSTRACT

SPOR domains are present in thousands of bacterial proteins and probably bind septal peptidoglycan (PG), but the details of the SPOR-PG interaction have yet to be elucidated. Here we characterize the structure and function of the SPOR domain for an Escherichia coli division protein named DamX. Nuclear magnetic resonance revealed the domain comprises a four-stranded antiparallel β-sheet buttressed on one side by two α-helices. A third helix, designated α3, associates with the other face of the β-sheet, but this helix is relatively mobile. Site-directed mutagenesis revealed the face of the β-sheet that interacts with α3 is important for septal localization and binding to PG sacculi. The position and mobility of α3 suggest it might regulate PG binding, but although α3 deletion mutants still localized to the septal ring, they were too unstable to use in a PG binding assay. Finally, to assess the importance of the SPOR domain in DamX function, we constructed and characterized E. coli mutants that produced DamX proteins with SPOR domain point mutations or SPOR domain deletions. These studies revealed the SPOR domain is important for multiple activities associated with DamX: targeting the protein to the division site, conferring full resistance to the bile salt deoxycholate, improving the efficiency of cell division when DamX is produced at normal levels, and inhibiting cell division when DamX is overproduced.