ponA
168

major Class A penicillin-binding protein 1A/1B, contributes to cell elongation and cell division, required for the control of cell diameter (together with the Rod complex)

Locus

BSU_22320

Molecular weight

99.36 kDa

Isoelectric point

4.75

Protein length

914 aaSequenceBlast

Gene length

2745 bpSequenceBlast

Function

bifunctional glucosyltransferase/ transpeptidase, polymerizes and cross-links peptidoglycan

Product

penicillin-binding protein 1A/1B, member of the divisome

Essential

Synonyms

ponA

Outlinks

BsubCyc SubtiList UniProt STRING Genoscapist PaperBLAST

Genomic Context

Hide small RNAsZoom:

Categories containing this gene/protein

List of homologs in different organisms, belongs to COG0744 (Galperin et al., 2021)

This gene is a member of the following regulons

Gene

Coordinates

2,341,444 2,344,188

Phenotypes of a mutant

the mutant tends to acquire suppressor mutations that result in improved growth PubMed

prevents bulging of the cells when grown at low Mg²⁺ concentrations, suppresses the lethal effect of a mreB mutation PubMed

deletion of ponA restores growth and normal shape of a glmR mutant on gluconeogenic carbon sources PubMed

a strain lacking all four class A penicillin-binding proteins (ponA pbpD pbpF pbpG) is severely inhibited for L-form switching in the presence of D-cycloserine PubMed

a sigI ponA double mutant is not viable due to its inability to repair gaps in the peptidoglycan mesh PubMed

reduced survival after DNA replication arrest imposed by inhibition of PolC activity PubMed

impaired growth on complex medium, this can be suppressed by the addition of Mg²⁺ or by deletion of mprF PubMed

ponA ecsA, ponA sigI, and ponA rasP double mutants have a growth defect that can be suppressed by reduced fatty acid synthesis (mutations in accA, accB, accC, accD or downregulation of the FapR regulon due to specific mutations in fapR) PubMed

The protein

Catalyzed reaction/ biological activity

[GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]_(n)-diphospho-di-trans,octa-cis-undecaprenol + β-D-GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)-diphospho-di-trans,octa-cis-undecaprenol --> [GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]_(n+1)-diphospho-di-trans-octa-cis-undecaprenol + di-trans,octa-cis-undecaprenyl diphosphate + H⁺ (according to UniProt)

Preferential cleavage: (Ac)(2)-L-Lys-D-Ala-|-D-Ala. Also transpeptidation of peptidyl-alanyl moieties that are N-acyl substituents of D-alanine (according to UniProt)

contributes to the control of cell diameter (cell diameter increases with PonA levels), acts antogonistically to the Rod complex PubMed

Protein family

N-terminal part: glycosyltransferase 51 family (according to UniProt)

C-terminal part: transpeptidase family (according to UniProt)

Domains

Fibronectin type-III (aa 708-795) (according to UniProt)

extracellular C-terminal intrinsically disordered region, directs synthase activity to sites of gaps in the peptidoglycan mesh to repair them PubMed

Structure

3DWK (PDB) (from Staphylococcus aureus, aa 71 ... 656, 38% identity) PubMed

P39793 (AlphaFold)

Paralogous protein(s)

PbpD, PbpF, PbpG