1lcb: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
New page: left|200px<br /><applet load="1lcb" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lcb, resolution 2.5Å" /> '''LACTOBACILLUS CASEI T...
 
No edit summary
 
(17 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[Image:1lcb.jpg|left|200px]]<br /><applet load="1lcb" size="450" color="white" frame="true" align="right" spinBox="true"
caption="1lcb, resolution 2.5&Aring;" />
'''LACTOBACILLUS CASEI THYMIDYLATE SYNTHASE TERNARY COMPLEX WITH DTMP AND H2FOLATE'''<br />


==Overview==
==LACTOBACILLUS CASEI THYMIDYLATE SYNTHASE TERNARY COMPLEX WITH DTMP AND H2FOLATE==
Crystal structures of two crystal forms of the complex of Lactobacillus, casei (TS) with its substrate dUMP have been solved and refined at 2.55 A, resolution. The two crystal forms differ by approximately 5% in the c-axis, length. The TS-dUMP complexes are symmetric dimers with dUMP bound, equivalently in both active sites. dUMP is non-covalently bound in the, same conformation as in ternary complexes of TS with dUMP and cofactor or, cofactor analogs. The same hydrogen bonds are made between TS and, substrate in the binary and ternary complexes. We have also determined the, 2.36 A crystal structure of phosphate-bound L. casei TS. This structure, has been refined to an R-factor of 19.3% with highly constrained geometry., Refinement has revealed the locations of all residues in the protein, including the disordered residues 90 to 119, which are part of an insert, found only in the L. casei and Staphylococcus aureus transposon Tn4003 TS, sequences. The 2.9 A multiple isomorphous replacement (MIR) structure of, L. casei TS in a complex with its substrate dUMP has been refined to a, crystallographic R-factor of 15.5%. Reducing agents were withheld from, crystallization solutions during MIR structure determination to allow, heavy-metal labeling of the cysteine residues. Therefore, the active-site, cysteine residue in this structure is oxidized and the dUMP is found at, half-occupancy in the active site. No significant conformational, difference was found between the phosphate-bound and dUMP-bound, structures. The TS-dUMP structures were better ordered than the, phosphate-bound TS or the oxidized TS-dUMP, particularly Arg23, which is, clearly hydrogen-bonded to the phosphate group of dUMP. A large and a, small P6(1)22 crystal form are observed for both phosphate-bound and, dUMP-bound L. casei TS. The small cell forms of the phosphate-bound and, dUMP-bound enzyme are isomorphous, whereas the cell constants of the, larger cell form change slightly when dUMP is bound (c = 240 A versus c =, 243 A). For both liganded and unliganded enzyme, conversion from the small, to the large crystal form sometimes occurs spontaneously, and the crystal, packing changes at a single interface. Conversion may be the result of a, small change in pH in the mother liquor surrounding the crystal. A single, intermolecular contact between symmetry-related Asp287 residues is, disrupted on going from the small to the large crystal form.
<StructureSection load='1lcb' size='340' side='right'caption='[[1lcb]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1lcb]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Lacticaseibacillus_casei Lacticaseibacillus casei]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LCB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1LCB 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]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DHF:DIHYDROFOLIC+ACID'>DHF</scene>, <scene name='pdbligand=TMP:THYMIDINE-5-PHOSPHATE'>TMP</scene></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=1lcb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1lcb OCA], [https://pdbe.org/1lcb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1lcb RCSB], [https://www.ebi.ac.uk/pdbsum/1lcb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1lcb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TYSY_LACCA TYSY_LACCA] Provides the sole de novo source of dTMP for DNA biosynthesis.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/lc/1lcb_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1lcb ConSurf].
<div style="clear:both"></div>


==About this Structure==
==See Also==
1LCB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Lactobacillus_casei Lactobacillus casei] with TMP and DHF as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Thymidylate_synthase Thymidylate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.45 2.1.1.45] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1LCB OCA].
*[[Thymidylate synthase 3D structures|Thymidylate synthase 3D structures]]
 
__TOC__
==Reference==
</StructureSection>
Refined structures of substrate-bound and phosphate-bound thymidylate synthase from Lactobacillus casei., Finer-Moore J, Fauman EB, Foster PG, Perry KM, Santi DV, Stroud RM, J Mol Biol. 1993 Aug 20;232(4):1101-16. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=8371269 8371269]
[[Category: Lacticaseibacillus casei]]
[[Category: Lactobacillus casei]]
[[Category: Large Structures]]
[[Category: Single protein]]
[[Category: Birdsall DL]]
[[Category: Thymidylate synthase]]
[[Category: Finer-Moore J]]
[[Category: Birdsall, D.L.]]
[[Category: Stroud RM]]
[[Category: Finer-Moore, J.]]
[[Category: Stroud, R.M.]]
[[Category: DHF]]
[[Category: TMP]]
[[Category: nucleotide synthase]]
 
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 20:28:22 2007''

Latest revision as of 10:31, 14 February 2024

LACTOBACILLUS CASEI THYMIDYLATE SYNTHASE TERNARY COMPLEX WITH DTMP AND H2FOLATELACTOBACILLUS CASEI THYMIDYLATE SYNTHASE TERNARY COMPLEX WITH DTMP AND H2FOLATE

Structural highlights

1lcb is a 1 chain structure with sequence from Lacticaseibacillus casei. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 2.5Å
Ligands:,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

TYSY_LACCA Provides the sole de novo source of dTMP for DNA biosynthesis.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

1lcb, resolution 2.50Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA