[en] A review with 95 refs. The assembly of the bacterial cell wall peptidoglycan relies upon the availability of a ready-made precursor, the lipid II intermediate. This intermediate is taken up by a multifunctional factory that provides the required enzymic activities for polymer assembly at the exterior of the plasma membrane. Morphogenetic networks regulate the synthesis in a cell-cycle-dependent fashion. As essential components of the cell machinery are targets of β-lactam antibiotics, safety devices protect the cells against these toxic agents. Controversy and consensus formation lie at the heart of the scientific research. This review focuses on questions that bacterial cell wall biochemists still strive, with increasing success, to answer. [on SciFinder(R)]
[en] As the protein sequence and structure databases expand, the relationships between proteins, the notion of protein superfamily, and the driving forces of evolution are better understood. Key steps of the synthesis of the bacterial cell wall peptidoglycan are revisited in light of these advances. The reactions through which the D-alanyl-D-alanine depeptide is formed, utilized, and hydrolyzed and the sites of action of the glycopeptide and β-lactam antibiotics illustrate the concept according to which new enzyme functions evolve as a result of tinkering of existing proteins. This occurs by the acquisition of local structural changes, the fusion into mul-timodular polypeptides, and the association into multiprotein complexes.
[Université de Liège - ULg > > Centre d'Ingénierie des Protéines > >]
