EC Number   |
General Information |
Reference  |
|---|
   2.7.8.43 | malfunction |
although Salmonella lipid A is more prevalently modified with L-4-aminoarabinose, loss of Salmonella lpxT greatly increases modification of lipid A through enzyme EptA, and LpxT-dependent lipid A modification is not restored in the DELTAeptA mutant. LpxT catalyses the phosphorylation of lipid A at the 1-position forming 1-diphosphate lipid A increasing the negative charge of the bacterial surface |
-, 723212 |
| 2.7.8.43 | malfunction |
eptA mutants show a 20fold decrease in polymyxin B resistanc. Overexpression of LpxT in trans in Escherichia coli strain WD101 results in loss of phosphoethanolamine modification and compromised WD101 polymyxin resistance |
723212 |
| 2.7.8.43 | metabolism |
PmrA is activated under Mg2+ limiting growth conditions or upon exposure to cationic antimicrobial peptides. Under these conditions PmrA activation is mediated by a second two-component system, PhoP/PhoQ. activation of PhoP in Salmonella induces the synthesis of PmrD, which regulates PmrA activity post-transcriptionally by preventing dephosphorylation of PmrA |
-, 723212 |
| 2.7.8.43 | physiological function |
EptA-dependent lipid A modification is required for resistance to polymyxin B, EptA plays a dominant role in polymyxin resistance. Enzyme PmrA is not involved in transcription of LpxT, which catalyses the phosphorylation of lipid A at the 1-position forming 1-diphosphate lipid A increasing the negative charge of the bacterial surface. LpxT-dependent lipid A modification is regulated post-translationally. The regulation does not occur at the level of transcription, but rather following the assembly of LpxT into the inner membrane. PmrA-dependent inhibition of LpxT is required for phosphoethanolamine decoration of lipid A, which is critical for Escherichia coli to resist the bactericidal activity of polymyxin |
723212 |
| 2.7.8.43 | physiological function |
EptA-dependent lipid A modification is required for resistance to polymyxin B. Expression of EptA (PmrC) is under the control of PmrA/PmrB |
-, 723212 |
| 2.7.8.43 | physiological function |
the enzyme phosphoethanolamine transferase A is involved in the addition of phosphoethanolamine moieties to lipid A |
-, 733017 |
| 2.7.8.43 | malfunction |
point mutations in the PmrA/B two-component system lead to colistin resistance |
733107 |
| 2.7.8.43 | metabolism |
the development of a moderate level of colistin resistance in Acinetobacter baumannii requires distinct genetic events, including (i) at least one point mutation in pmrB, (ii) upregulation of pmrAB, and (iii) expression of pmrC, which lead to addition of phosphoethanolamine to lipid A |
733107 |
| 2.7.8.43 | physiological function |
phosphoethanolamine modification of lipid A in colistin-resistant variants of Acinetobacter baumannii, e.g. strain ATCC 19606, is mediated by the pmrAB two-component regulatory system |
733107 |
| 2.7.8.43 | malfunction |
loss of the enzyme activity increases bacterial sensitivity to killing by human complement and cationic antimicrobial peptides, lptA mutant Neisseria gonorrhoeae is significantly more sensitive to killing by human neutrophils |
-, 733635 |
