Activating Compound | Comment | Organism | Structure |
---|---|---|---|
DMSO | 20% DMSO has a positive effect on the GTase rate of PBP1B, particularly at the higher Triton X-100 concentration of 0.2%. At higher Triton X-100 concentration in the presence of 20% DMSO the stimulation of PBP1B by LpoB is only 1.6fold | Escherichia coli |
Cloned (Comment) | Organism |
---|---|
overexpression of His-tagged enzyme in Escherichia coli strain BL21 pDML924 | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | inhibitory effect of high detergent concentration on the enzyme activity. 25% Dimethylsulfoxide (DMSO) abrogates this detergent effect | Escherichia coli |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | - |
Escherichia coli | 16020 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | Escherichia coli | natural substrate is lipid II | ? | - |
- |
|
[GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)]n-diphosphoundecaprenol + GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)-diphosphoundecaprenol | Escherichia coli | - |
[GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)]n+1-diphosphoundecaprenol + undecaprenyl diphosphate | - |
? |
Organic Solvent | Comment | Organism |
---|---|---|
additional information | organic solvent DMSO is a component of in vitro peptidoglycan synthesis assays making use of its ability to solubilize the lipid II substrate without denaturing enzymes. DMSO at high concentration can potentially affect protein stability and protein-protein interactions. The presence of 20% DMSO severely impairs the interaction of PBP1B with LpoB. In contrast, at lower concentration of Triton X-100 (between 0.02% and 0.08%) the activity of PBP1B can be robustly assayed and its interactions with LpoB, CpoB, TolA and FtsN are maintained. Inhibitory effect of high detergent concentration on the enzyme activity. 25% Dimethylsulfoxide (DMSO) abrogates this detergent effect | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P02919 | - |
- |
Purification (Comment) | Organism |
---|---|
gene mrcB, recombinant His-tagged PBP1B from Escherichia coli strain BL21 pDML924 membrane fraction by ultracentrifugation, nickel affinity chromatography, dialysis, and tag cleavage by thrombin, followed by dialysis, cation exchange chromatography and again diaylsis, method overview | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | natural substrate is lipid II | Escherichia coli | ? | - |
- |
|
additional information | fluorescence enzyme assay optimization and evaluation, detailed overview | Escherichia coli | ? | - |
- |
|
[GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)]n-diphosphoundecaprenol + GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)-diphosphoundecaprenol | - |
Escherichia coli | [GlcNAc-(1->4)-Mur2Ac(oyl-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala)]n+1-diphosphoundecaprenol + undecaprenyl diphosphate | - |
? |
Synonyms | Comment | Organism |
---|---|---|
DD-transpeptidase | - |
Escherichia coli |
GTase | - |
Escherichia coli |
PBP | - |
Escherichia coli |
PBP1b | - |
Escherichia coli |
penicillin-binding protein | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
assay at room temperature | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Escherichia coli |
General Information | Comment | Organism |
---|---|---|
physiological function | the majority of bacteria surround their cytoplasmic membrane with a peptidoglycan sacculus, a continuous layer that is required to maintain cell shape and osmotic stability. The basic chemical structure of peptidoglycan is well known, glycan strands consisting of alternating N -acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc) residues connected by short stem peptides protruding from MurNAc. Peptides of neighboring glycan strands may be connected (i.e. cross-linked) forming a net-like layer. Peptide cross-links are formed by DD-transpeptidases. DD-transpeptidases covalently bind beta-lactam antibiotics such as penicillin, and are hence named penicillin-binding proteins (PBPs). Most bacteria possess several peptidoglycan synthases capable of catalyzing the glycosyltransferase (GTase) and/or transpeptidase (TPase) reactions. The Gram negative model organism Escherichia coli has three enzymes capable of performing both reactions, so-called bifunctional synthases: PBP1A, PBP1B, and PBP1C, two monofunctional transpeptidases, PBP2 and PBP3, and the monofunctional glycosyltransferase MtgA. The main peptidoglycan synthesis activity in the cell is provided by the semi-redundant PBP1A and PBP1B in consort with the transpeptidases PBP2 and PBP3, latter have essential roles in cell elongation and division, respectively. PBP1C and MtgA are dispensable for growth | Escherichia coli |