View source for 5dec


==Crystal structure of the small alarmone synthetase 1 from Bacillus subtilis==
<StructureSection load='5dec' size='340' side='right'caption='[[5dec]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5dec]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_subtilis_subsp._subtilis_str._168 Bacillus subtilis subsp. subtilis str. 168]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5DEC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5DEC FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5dec FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5dec OCA], [https://pdbe.org/5dec PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5dec RCSB], [https://www.ebi.ac.uk/pdbsum/5dec PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5dec ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/YJBM_BACSU YJBM_BACSU] Functions as a (p)ppGpp synthase. In eubacteria ppGpp (guanosine 3'-diphosphate 5-' diphosphate) is a mediator of the stringent response that coordinates a variety of cellular activities in response to changes in nutritional abundance. YjbM has probably a minor role in stringent response.<ref>PMID:18067544</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Nucleotide-based second messengers serve in the response of living organisms to environmental changes. In bacteria and plant chloroplasts, guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp) [collectively named "(p)ppGpp"] act as alarmones that globally reprogram cellular physiology during various stress conditions. Enzymes of the RelA/SpoT homology (RSH) family synthesize (p)ppGpp by transferring pyrophosphate from ATP to GDP or GTP. Little is known about the catalytic mechanism and regulation of alarmone synthesis. It also is unclear whether ppGpp and pppGpp execute different functions. Here, we unravel the mechanism and allosteric regulation of the highly cooperative alarmone synthetase small alarmone synthetase 1 (SAS1) from Bacillus subtilis. We determine that the catalytic pathway of (p)ppGpp synthesis involves a sequentially ordered substrate binding, activation of ATP in a strained conformation, and transfer of pyrophosphate through a nucleophilic substitution (SN2) reaction. We show that pppGpp-but not ppGpp-positively regulates SAS1 at an allosteric site. Although the physiological significance remains to be elucidated, we establish the structural and mechanistic basis for a biological activity in which ppGpp and pppGpp execute different functional roles.

Catalytic mechanism and allosteric regulation of an oligomeric (p)ppGpp synthetase by an alarmone.,Steinchen W, Schuhmacher JS, Altegoer F, Fage CD, Srinivasan V, Linne U, Marahiel MA, Bange G Proc Natl Acad Sci U S A. 2015 Oct 27;112(43):13348-53. doi:, 10.1073/pnas.1505271112. Epub 2015 Oct 12. PMID:26460002<ref>PMID:26460002</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5dec" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus subtilis subsp. subtilis str. 168]]
[[Category: Large Structures]]
[[Category: Altegoer A]]
[[Category: Bange G]]
[[Category: Schuhmacher JS]]
[[Category: Steinchen W]]