2le2: Difference between revisions
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[[2le2]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bacillus_phage_phi29 Bacillus phage phi29]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LE2 OCA]. <br> | [[2le2]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bacillus_phage_phi29 Bacillus phage phi29]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LE2 OCA]. <br> | ||
<b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | <b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | ||
<b>Resources:</b> <span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2le2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2le2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2le2 RCSB], [http://www.ebi.ac.uk/pdbsum/2le2 PDBsum]</span><br> | |||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
Protein p56 encoded by the Bacillus subtilis phage 29 inhibits the host uracil-DNA glycosylase (UDG) activity. To get insights into the structural basis for this inhibition, the NMR solution structure of p56 has been determined. The inhibitor defines a novel dimeric fold, stabilized by a combination of polar and extensive hydrophobic interactions. Each polypeptide chain contains three stretches of anti-parallel beta-sheets and a helical region linked by three short loops. In addition, microcalorimetry titration experiments showed that it forms a tight 2:1 complex with UDG, strongly suggesting that the dimer represents the functional form of the inhibitor. This was further confirmed by the functional analysis of p56 mutants unable to assemble into dimers. We have also shown that the highly anionic region of the inhibitor plays a significant role in the inhibition of UDG. Thus, based on these findings and taking into account previous results that revealed similarities between the association mode of p56 and the phage PBS-1/PBS-2-encoded inhibitor Ugi with UDG, we propose that protein p56 might inhibit the enzyme by mimicking its DNA substrate. | Protein p56 encoded by the Bacillus subtilis phage 29 inhibits the host uracil-DNA glycosylase (UDG) activity. To get insights into the structural basis for this inhibition, the NMR solution structure of p56 has been determined. The inhibitor defines a novel dimeric fold, stabilized by a combination of polar and extensive hydrophobic interactions. Each polypeptide chain contains three stretches of anti-parallel beta-sheets and a helical region linked by three short loops. In addition, microcalorimetry titration experiments showed that it forms a tight 2:1 complex with UDG, strongly suggesting that the dimer represents the functional form of the inhibitor. This was further confirmed by the functional analysis of p56 mutants unable to assemble into dimers. We have also shown that the highly anionic region of the inhibitor plays a significant role in the inhibition of UDG. Thus, based on these findings and taking into account previous results that revealed similarities between the association mode of p56 and the phage PBS-1/PBS-2-encoded inhibitor Ugi with UDG, we propose that protein p56 might inhibit the enzyme by mimicking its DNA substrate. | ||