1k25

<table><tr><td colspan='2'>[[1k25]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/"diplococcus_pneumoniae"_(klein_1884)_weichselbaum_1886 "diplococcus pneumoniae" (klein 1884) weichselbaum 1886]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1K25 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1K25 FirstGlance]. <br>

</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1qmf|1qmf]], [[1qme|1qme]]</div></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

Penicillin-binding proteins (PBPs) are the main targets for beta-lactam antibiotics, such as penicillins and cephalosporins, in a wide range of bacterial species. In some Gram-positive strains, the surge of resistance to treatment with beta-lactams is primarily the result of the proliferation of mosaic PBP-encoding genes, which encode novel proteins by recombination. PBP2x is a primary resistance determinant in Streptococcus pneumoniae, and its modification is an essential step in the development of high level beta-lactam resistance. To understand such a resistance mechanism at an atomic level, we have solved the x-ray crystal structure of PBP2x from a highly penicillin-resistant clinical isolate of S. pneumoniae, Sp328, which harbors 83 mutations in the soluble region. In the proximity of the Sp328 PBP2x* active site, the Thr(338) --&gt; Ala mutation weakens the local hydrogen bonding network, thus abrogating the stabilization of a crucial buried water molecule. In addition, the Ser(389) --&gt; Leu and Asn(514) --&gt; His mutations produce a destabilizing effect that generates an "open" active site. It has been suggested that peptidoglycan substrates for beta-lactam-resistant PBPs contain a large amount of abnormal, branched peptides, whereas sensitive strains tend to catalyze cross-linking of linear forms. Thus, in vivo, an "open" active site could facilitate the recognition of distinct, branched physiological substrates.

Crystal structure of PBP2x from a highly penicillin-resistant Streptococcus pneumoniae clinical isolate: a mosaic framework containing 83 mutations.,Dessen A, Mouz N, Gordon E, Hopkins J, Dideberg O J Biol Chem. 2001 Nov 30;276(48):45106-12. Epub 2001 Sep 11. PMID:11553637<ref>PMID:11553637</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

</div>

<div class="pdbe-citations 1k25" style="background-color:#fffaf0;"></div>

== References ==

<references/>

[[Category: Dessen, A]]

[[Category: Dideberg, O]]

[[Category: Hopkins, J]]

[[Category: Mouz, N]]

[[Category: Membrane protein]]