2je5: Difference between revisions

beta-lactam antibiotics, including penicillins and cephalosporins, inhibit, penicillin-binding proteins (PBPs), which are essential for bacterial cell, wall biogenesis. Pathogenic bacteria have evolved efficient antibiotic, resistance mechanisms that, in Gram-positive bacteria, include mutations, to PBPs that enable them to avoid beta-lactam inhibition. Lactivicin (LTV;, 1) contains separate cycloserine and gamma-lactone rings and is the only, known natural PBP inhibitor that does not contain a beta-lactam. Here we, show that LTV and a more potent analog, phenoxyacetyl-LTV (PLTV; 2), are, active against clinically isolated, penicillin-resistant Streptococcus, pneumoniae strains. Crystallographic analyses of S. pneumoniae PBP1b, reveal that LTV and PLTV inhibition involves opening of both monocyclic, cycloserine and gamma-lactone rings. In PBP1b complexes, the ring-derived, atoms from LTV and PLTV show a notable structural convergence with those, derived from a complexed cephalosporin (cefotaxime; 3). The structures, imply that derivatives of LTV will be useful in the search for new, antibiotics with activity against beta-lactam-resistant bacteria.

2JE5 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptococcus_pneumoniae Streptococcus pneumoniae] with SO4, CL and L4C as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2JE5 OCA].  

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