Characterization of antithrombins produced by active site mutagenesis of human alpha 1-antitrypsin expressed in yeast.
Both congenital and acquired antithrombin-III (AT-III) deficiencies are amenable to replacement therapy. We describe two antithrombins produced by recombinant DNA techniques from human alpha 1-antitrypsin (alpha 1AT) cDNA in yeast. Alteration of the alpha 1AT active site, replacing methionine 358 with arginine, results in a thrombin inhibition rate similar to that of heparin-activated AT-III. Alteration of two further residues, to give a five-residue sequence identical to AT-III, does not increase this rate further. Neither antithrombin is activated by heparin; both are unglycosylated and have shorter in vivo half-lives (t1/2) than human alpha 1AT. These antithrombins should be suitable for therapeutic replacement of AT-III in cases of congenital deficiency and in conditions associated with acquired AT-III deficiency, such as disseminated intravascular coagulation.
George
P M
PM
Department of Pathology, Christchurch Hospital, New Zealand.
Pemberton
P
P
Bathurst
I C
IC
Carrell
R W
RW
Gibson
H L
HL
Rosenberg
S
S
Hallewell
R A
RA
Barr
P J
PJ
D000595:Amino Acid Sequence; D000991:Antithrombins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D004355:Drug Stability; D014644:Genetic Variation; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D011994:Recombinant Proteins / Q000138:chemical synthesis* / Q000302:isolation & purification / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D000515:alpha 1-Antitrypsin / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
D000991:Antithrombins; D011994:Recombinant Proteins; D000515:alpha 1-Antitrypsin