Zymogenetics, Inc.

Catch, Inc.

Optein, Inc.

Other

Glenn H Kawasaki

Leslie Bell

Jeffrey Owens

Mark Legaz

Doreen Forest

Sobomabo Lawson

Heather Kay Webb

Raymond Liedtke

Margaret Y Insley

Meher H Irani

Richard W Woodbury

The present invention provides an enzymatic cycling assay for assessing the amount of homocysteine and/or cystathionine in a solution such as blood, blood derivatives, or urine. The assay comprises the steps of contacting the solution containing homocysteine and/or cystathionine to form a reaction mixture, with CBS, or a derivative thereof, L-serine, and CBL, or a derivative thereof, for a time period sufficient to catalyze the cyclical conversion of homocysteine form to cystathionine and the reconversion of cystathionine to homocysteine with the production of pyruvate and ammonia; determining the amount of homocysteine and/or ammonia present in the reaction mixture; and determining the amount of homocysteine and/or cystathionine present in the solution based on the amount of pyruvate and/or ammonia formed. Expression vectors and isolation procedures for CBS, or derivatives thereof, and CBL, or derivatives thereof, are also provided as well as test kits for carrying out the assay. In preferred embodiments, the assays can be conducted in 15 minutes or less, with a minimum of enzyme usage.

Enzymatic cycling assays for homocysteine and cystathionine

The present invention provides an enzymatic cycling assay for assessing the amount of homocysteine and/or cystathionine in a solution such as blood, blood, derivatives, or urine. The assay comprises the steps of contacting the solution containing homocysteine and/or cystathionine to form a reaction mixture, with CBS, or a derivative thereof, L-serine, and CBL, or a derivative thereof, for a time period sufficient to catalyze the cyclical conversion of homocysteine form to cystathionine and the reconversion of cystathionine to homocysteine with the production of pyruvate and ammonia; determining the amount of homocysteine and/or ammonia present in the reaction mixture; and determining the amount of homocysteine and/or cystathionine present in the solution based on the amount of pyruvate and/or ammonia formed. Expression vectors and isolation procedures for CBS, or derivatives thereof, and CBL, or derivatives thereof, are also provided as well as test kits for carrying out the assay. In preferred embodiments, the assays can be conducted in 15 minutes or less, with a minimum of enzyme usage.

Methods are provided for producing protein products in host cells and for selecting transformed cells comprising the step of transforming the host cell with a DNA molecule comprising a gene which complements a deficiency in the host cell. The host cell is s strain having a deficiency in a function necessary for normal cell growth. The gene in the DNA molecule, such as a plasmid, which complements the deficiency serves as a selection marker whereby the growth conditions for selection may comprise a conventional complex medium.

Stable DNA constructs

Methods are provided for producing protein products in host cells and for selecting transformed cells comprising the step of transforming the host cell with a DNA molecule comprising a gene which complements a deficiency in the host cell. The host cell is a strain having a deficiency in a function necessary for normal cell growth. The gene in the DNA molecule, such as a plasmid, which complements the deficiency serves as a selection marker whereby the growth conditions for selection may comprise a conventional complex medium.

A method for the cell-free synthesis and isolation of novel genes and polypeptides is provided. Within one embodiment, an expression unit is constructed onto which semi-random nucleotide sequences are attached. The semi-random nucleotide sequences are first transcribed to produce RNA, and then translated under conditions such that polysomes are produced. Polysomes which bind to a substance of interest are then isolated and disrupted; and the released mRNA is recovered. The mRNA is used to construct cDNA which is expressed to produce novel polypeptides.

Cell-free synthesis and isolation of novel genes and polypeptides

Promoters associated with expression of specific enzymes in the glycolytic pathway are used for expression of alien DNA, particularly yeast promoters known to provide high enzyme levels of enzymes in the glycolytic pathway are employed for expressing a mammalian protein, such as .alpha..sub.1 -antitrypsin. The promoters include promoters involved in expression of pyruvate kinase, triose phosphate isomerase, phosphoglucose isomerase, phosphoglycerate mutase, hexokinase 1, hexokinase 2, glucokinase, phosphofructokinase, and aldolase, as well as the glycolytic regulation gene. Particularly, the glycolytic regulation gene can be used in conjunction with promoters in the glycolytic pathway for regulated production of desired proteins.

Glycolytic promoters for regulated protein expression: protease inhibitor

Methods are provided for producing .alpha.-1-antitrypsin in host cells and for selecting transformed cells comprising the step of transforming the host cell with a DNA molecule comprising a gene which complements a deficiency in the host cell. The host cell is a strain having a deficiency in a function necessary for normal cell growth. The gene in the DNA molecule, such as a plasmid, which complements the deficiency serves as a selectable marker whereby the growth conditions for selection may comprise a conventional complex medium.

Stable DNA constructs for expression of .alpha.-1 antitrypsin

A method is provided for expressing human alpha-1-antitrypsin in yeast utilizing a wild-type strain and a hyperproduction mutant, GK100.

Method of expressing alpha-1-antitrypsin in yeast

Methods are provided for producing sites specific mutagenized alpha-1-antitrypsin. Particular mutants are formed having a mutation in the active site of alpha-1-antitrypsin at amino acid position 358 and at amino acid position 342.

Site specific mutagenesis in alpha-1-antitrypsin

Promoters associated with expression of specific enzymes in the glycolytic pathway are used for expression of alien DNA, particularly yeast promoters known to provide high enzyme levels of enzymes in the glycolytic pathway are employed for expressing a mammalian protein, such as .alpha..sub.1 -antitrypsin. The promoters include promoters involved in expression of pyruvate kinase, triose phosphate isomerase, phosphoglucose isomerase, phosphoglycerate mutase, hexokinase 1, hexokinase 2, glucokinase, phosphofructokinase, and aldolase, as well as the glycolytic regulation gene. Particularly, the glycolytic regulation gene can be used in conjuction with promoters in the glycolytic pathway for regulated production of desired proteins.

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Seattle, WA, United States of America

Glenn H Kawasaki