Linked Life Data

8506345

Source:http://linkedlifedata.com/resource/pubmed/id/8506345

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1993-7-7
pubmed:abstractText
The tightly binding and readily exchanging metal binding sites in the active site of bovine lens leucine aminopeptidase (blLAP; EC 3.4.11.1) have been differentiated and identified by x-ray crystallography. In native blLAP,Zn2+ occupies both binding sites. In solution, site 1 readily exchanges Zn2+ for other divalent cations, including Mg2+. The Zn2+ in site 2 is unavailable for metal exchange under conditions which allow exchange at site 1. The Zn2+/Mg2+ metal hybrid of blLAP (Mg-blLAP) was prepared in solution and crystallized. X-ray diffraction data to 2.9-A resolution were collected at -150 degrees C from single crystals of Mg-blLAP and native blLAP. Comparisons of omit maps calculated from the Mg-blLAP data with analogous maps calculated from the native blLAP data show electron density in one of the metal binding sites in Mg-blLAP which is much weaker than the electron density in the other binding site. Since there are fewer electrons associated with Mg2+ than with Zn2+, the difference in electron density between the two metal binding sites is consistent with occupancy of the weaker electron density site by Mg2+ and identifies this metal binding site as site 1, defined as the readily exchanging site. The present identification of the metal binding sites reverses the previous presumptive assignment of the metal binding sites which was based on the structure of native blLAP [Burley, S. K., David, P. R., Sweet, R. M., Taylor, A. & Lipscomb, W. N. (1992) J. Mol. Biol. 224, 113-140]. According to the residue-numbering convention of native blLAP, the new assignment of the metal binding sites identifies the readily exchanging site 1 with Zn-488, which is within interaction distance of one side-chain carboxylate oxygen from each of Asp-255, Asp-332, and Glu-334 and the main-chain carbonyl oxygen of Asp-332. The more tightly binding site 2 is identified with Zn-489, which is within interaction distance of one side-chain carboxylate oxygen from each of Asp-255, Asp-273, and Glu-334 and the side-chain amine nitrogen of Lys-250.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-1254587, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-13233230, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-1548695, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-17810339, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-1871107, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-2395881, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-240944, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-2670557, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-3167029, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-3841179, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-402, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-537086, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-5389722, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-6615800, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-7295698, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-7310866, http://linkedlifedata.com/resource/pubmed/commentcorrection/8506345-881727
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5006-10
pubmed:dateRevised
2010-9-13
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Differentiation and identification of the two catalytic metal binding sites in bovine lens leucine aminopeptidase by x-ray crystallography.
pubmed:affiliation
Gibbs Chemical Laboratory, Harvard University, Cambridge, MA 02138.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.