Judy Luke

Author's posts

Site2 binding energetics of the regulatory step of growth hormone-induced receptor homodimerization

Walsh ST, Jevitts LM, Sylvester JE, Kossiakoff AA

Protein Sci. 2003 Sep;12(9):1960-70

PMID: 12930995

Abstract

Receptor signaling in the growth hormone (GH)-growth hormone receptor (GHR) system is controlled through a sequential two-step hormone-induced dimerization of two copies of the extracellular domain (ECD) of the receptor. The regulatory step of this process is the binding of …

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The functional binding epitope of a high affinity variant of human growth hormone mapped by shotgun alanine-scanning mutagenesis: insights into the mechanisms responsible for improved affinity

Pal G, Kossiakoff AA, Sidhu SS

J. Mol. Biol. 2003 Sep;332(1):195-204

PMID: 12946357

Abstract

A high-affinity variant of human growth hormone (hGH(v)) contains 15 mutations within site 1 and binds to the hGH receptor (hGHR) approximately 400-fold tighter than does wild-type (wt) hGH (hGH(wt)). We used shotgun scanning combinatorial mutagenesis to dissect the energetic contributions …

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The first semi-synthetic serine protease made by native chemical ligation

Pál G, Santamaria F, Kossiakoff AA, Lu W

Protein Expr. Purif. 2003 Jun;29(2):185-92

PMID: 12767808

Abstract

Selective incorporation of non-natural amino acid residues into proteins is a powerful approach to delineate structure-function relationships. Although many methodologies are available for chemistry-based protein engineering, more facile methods are needed to make this approach suitable for routine laboratory …

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Determination of the energetics governing the regulatory step in growth hormone-induced receptor homodimerization

Bernat B, Pal G, Sun M, Kossiakoff AA

Proc. Natl. Acad. Sci. U.S.A. 2003 Feb;100(3):952-7

PMID: 12552121

Abstract

Signaling in the human growth hormone (hGH)-human GH receptor system is initiated by a controlled sequential two-step hormone-induced dimerization of two hGH receptors via their extracellular domains (ECDs). Little is currently known about the energetics governing the …

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Structure of a phage display-derived variant of human growth hormone complexed to two copies of the extracellular domain of its receptor: evidence for strong structural coupling between receptor binding sites

Schiffer C, Ultsch M, Walsh S, Somers W, de Vos AM, Kossiakoff A

J. Mol. Biol. 2002 Feb;316(2):277-89

PMID: 11851338

Abstract

The structure of the ternary complex between the phage display- optimized, high-affinity Site 1 variant of human growth hormone (hGH) and two copies of the extracellular domain (ECD) of the hGH receptor (hGHR) has …

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High affinity RNase S-peptide variants obtained by phage display have a novel “hot-spot” of binding energy

Dwyer JJ, Dwyer MA, Kossiakoff AA

Biochemistry 2001 Nov;40(45):13491-500

PMID: 11695896

Abstract

Using phage display mutagenesis, high affinity variants of RNase S-peptide were produced that bind to RNase S-protein over 100-fold more tightly than the wild type S-peptide. The S-peptide: S-protein interface was further characterized using “biased” phage display libraries, where each targeted residue was …

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Biosynthetic phage display: a novel protein engineering tool combining chemical and genetic diversity

Dwyer MA, Lu W, Dwyer JJ, Kossiakoff AA

Chem. Biol. 2000 Apr;7(4):263-74

PMID: 10780926

Abstract

BACKGROUND: Molecular diversity in nature is developed through a combination of genetic and chemical elements. We have developed a method that permits selective manipulation of both these elements in one protein engineering tool. It combines the ability to introduce non-natural …

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