Recombinant soluble human tissue factor secreted by Saccharomyces cerevisiae and refolded from Escherichia coli inclusion bodies: Glycosylation of mutants, activity and physical characterization

M. J. Stone, W. Ruf, D. J. Miles, T. S. Edgington, P. E. Wright

Research output: Contribution to journalArticleResearchpeer-review

81 Citations (Scopus)

Abstract

Tissue factor (TF) is the cell-surface transmembrane receptor that initiates both the extrinsic and intrinsic blood coagulation cascades. The abilities of TF to associate with Factor VIIa and Factor X in a ternary complex and to enable proteolytic activation of Factor X by Factor VIIa reside in the extracellular domain of TF. We describe the expression of the surface domain of TF (truncated TF, tTF) in both Saccharomyces cerevisiae and Escherichia coli and the biochemical and physical characterization of the recombinant proteins. Wild-type tTF and several glycosylation-site mutants were secreted efficiently by S. cerevisiae under the control of the yeast prepro-α-signal sequence; the T13A,N137D double mutant was the most homogeneous variant expressed in milligram quantities. Wild-type tTF was expressed in a non-native state in E. coli inclusion bodies as a fusion protein with a poly(His) leader. The fusion protein could be fully renatured and the leader removed by proteolysis with thrombin; the correct molecular mass (24 729 Da) of the purified protein was confirmed by electrospray mass spectrometry. Recombinant tTFs from yeast, E. coli and Chinese hamster ovary cells were identical in their abilities to bind Factor VIIa, to enhance the catalytic activity of Factor VIIa and to enhance the proteolytic activation of Factor X by Factor VIIa. Furthermore, CD, fluorescence emission and NMR spectra of the yeast and E. coli proteins indicated that these proteins are essentially identical structurally.

Original languageEnglish
Pages (from-to)605-614
Number of pages10
JournalBiochemical Journal
Volume310
Issue number2
Publication statusPublished - 1995
Externally publishedYes

Cite this