Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1996-8-15
pubmed:abstractText
As discussed in the accompanying paper [Markland, W., Ley, A. C., & Ladner, R. C. (1996) Biochemistry 35, 8045-8057], we generated libraries from the first Kunitz domain of human lipoprotein-associated coagulation inhibitor (LACI-D1) using multivalent M13 III display and derived potent inhibitors of human plasmin (PLA) by iterative variegation and selection. Here, we show that high-affinity, high-specificity binders to human plasma kallikrein (pKAL) and human thrombin (THBN) can be obtained starting from the identical library and employing the same iterative variegation procedures used to obtain PLA inhibitors. Lib#1 (allowing 31 200 variants involving five positions near the P1 residue of LACI-D1) and its pKAL-biased derivative, Lib#4 (allowing an additional 1600 variants at residues 31, 32, 34, and 39), were screened against pKAL, yielding potent inhibitors. One of these, EPI-K401, has Ki = 284 pM, very high specificity, and excellent stability. We used information from Lib#4 selectants to design Lib#5 (allowing 1.5 x 10(6) amino-acid sequences involving nine varied positions) from which we obtained an inhibitor (EPI-K503) having high affinity for pKAL (Ki = 40 pM) and retaining the high specificity of EPI-K401. When we screened Lib#1 and its THBN-tailored derivative, Lib#6, against THBN, we obtained a different and very homogeneous population of selected molecules. The purified proteins derived from Lib#6 selectants bound to THBN-agarose beads but did not inhibit proteolytic activity of THBN, suggesting that these selectants bind to a site on THBN other than the catalytic site. Thus, a single large combinatorial library can serve as a source to obtain highly specific, high-affinity binding molecules for each of several targets. Furthermore, the results with THBN show that the binding of Kunitz domains to other proteins is not limited to the catalytic sites of trypsin-homologous proteases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8058-67
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:8672510-Amino Acid Sequence, pubmed-meshheading:8672510-Aprotinin, pubmed-meshheading:8672510-Bacteriophage M13, pubmed-meshheading:8672510-Binding Sites, pubmed-meshheading:8672510-Cloning, Molecular, pubmed-meshheading:8672510-Drug Stability, pubmed-meshheading:8672510-Gene Library, pubmed-meshheading:8672510-Genetic Variation, pubmed-meshheading:8672510-Humans, pubmed-meshheading:8672510-Kallikreins, pubmed-meshheading:8672510-Kinetics, pubmed-meshheading:8672510-Lipoproteins, pubmed-meshheading:8672510-Molecular Sequence Data, pubmed-meshheading:8672510-Pichia, pubmed-meshheading:8672510-Saccharomyces cerevisiae, pubmed-meshheading:8672510-Sequence Homology, Amino Acid, pubmed-meshheading:8672510-Serine Proteinase Inhibitors, pubmed-meshheading:8672510-Thermodynamics, pubmed-meshheading:8672510-Thrombin
pubmed:year
1996
pubmed:articleTitle
Iterative optimization of high-affinity protease inhibitors using phage display. 2. Plasma kallikrein and thrombin.
pubmed:affiliation
Protein Engineering Corporation, Cambridge, Massachusetts 02138, USA.
pubmed:publicationType
Journal Article, Comparative Study