Abstract: Restriction enzymes are used to remove from DNA a complete and undamaged structural gene coding region for the expression of DNA polymerase I (polA) without the gene's natural promoter or with only a significantly damaged portion of the gene's natural promoter. Also by the use of restriction enzymes, a segment from a plasmid cloning vector is excised at a position adjacent to a promoter which is conditionally controllable and may be more powerful than the damaged or removed promoter. The gene for DNA polymerase I is enzymatically cloned into said vector at the position of said removed segment and adjacent to said conditionally controllable promoter. Multicopies of the cloned vector are introduced into a host baterial strain (E. coli). The host strain is then cultured so that the cell colony grows and replicates new generations containing replicated foreign plasmid. During such said replication the activity of said controllable promoter is repressed.

Abstract: The present invention relates to drugs characterized in that they comprise, in association, at least one immunotoxin and at least one monovalent carboxylic ionophore.

Abstract: In vitro production of RNA copies of either strand of any cloned DNA sequence may be obtained utilizing a unique cloning vector having two different opposed promoter sequences which are separated by a multiple cloning site. RNA polymerases which recognize only one of the particular promoter sequences in the vector may be applied to obtain transcription which proceeds from the recognized promoter toward the other promoter. Transcription of a desired strand of any DNA sequence is obtained by cleaving a particular restriction site in the multiple cloning site between the two promoter sequences, cloning the desired DNA sequence into the cleaved site, then cleaving another site between the two promoters which is distal to the promoter from which transcription is desired. The RNA polymerase which recognizes the selected promoter may then be applied to the vector to obtain transcription of the selected DNA sequence in vitro.

Abstract: Methods for expressing a variety of biologically active PDGF analogs in eucaryotic cells are disclosed. The methods generally comprise introducing into a eucaryotic host cell a DNA construct capable of directing the expression and secretion of biologically active PDGF analogs in eucaryotic cells. The DNA construct contains a transcriptional promoter followed downstream by a suitable DNA sequence. The DNA sequence may encode a protein substantially homologous to the A-chain or the B-chain of PDGF, or a portion thereof, or an A-B heterodimer. In addition, a portion of the DNA sequence may encode at least a portion of the A-chain, while another portion encodes at least a portion of the B-chain of PDGF. Eucaryotic cells transformed with these DNA constructs are also disclosed. Methods of promoting the growth of mammalian cells, comprising incubating the cells with a biologically active PDGF analog expressed by a eucaryotic host cell transformed with such a DNA construct, are also disclosed.

Abstract: An expression vector, a plasmid containing yeast alcohol dehydrogenase I promoter and terminator and the gene coding for the rat liver cytochrome P-450MC gene Saccharomyces cerevisiae transformed with the plasmid and process for preparing rat liver cytochrome P-450MC.

Abstract: Ice nucleation bacteria are modified in vitro to confer an ice nucleation deficient phenotype. Modification is accomplished by deletion, substitution, insertion, inversion, or transversion of a DNA segment within the gene locus responsible for the INA phenotype. By limiting such mutations to the particular gene locus, the modified microorganisms are genetically stable and free from random mutations which might adversely affect their competitive fitness. The modified microorganisms are useful for prevention of frost damage to susceptible plant hosts.

Abstract: Human tissue phasminogen activator (t-PA) is produced in useful quantities using recombinant DNA techniques. The invention disclosed thus enables the production of t-PA free of contaminants with which it is ordinarily associated in its native cellular environment. Methods, expression vehicles and various host cells useful in its production are also disclosed.

Abstract: A recombinant vector adapted for transformation of a suitable bacterial microorganism host to produce and secrete streptokinase. The recombinant vector comprises a plasmid into which a polydeoxyribonucleotide fragment from Streptococcus equisimilis H46A which codes for streptokinase synthesis and secretion has been inserted. The transformant bacterial microorganism including this recombinant plasmid vector produces streptokinase suitable for clinical fibrinolytic usage after purification.

Abstract: Proteins having a hydrophobic cavity proximate to which is a residue promoting hydrolysis of functional moieties are effective semisynthetic hydrolases. Heme proteins from which the heme has been removed usually have at least one imidazole residue proximate to the cavity, and thus act as quite effective esterases. Because the size and shape of the cavities of such proteins are capable of broad diversity a wide spectrum of substrates may be hydrolyzed by these semisynthetic enzymes.

Abstract: A vaccine against a microbial pathogen comprised of a live, immunogenic but prototrophic and avirulent mutant strain of the selected microbial pathogen in an amount effective to confer immunity. A method of obtaining a vaccine that induces a heightened cellular and humoral immune response to one of a variety of microbial pathogens in a warm blooded animal. A method for isolation of an avirulent strain of a selected pathogenic microorganism.

Abstract: A lipid coupling reagent for use in coupling amine-containing molecules, such as proteins, to liposomes. The reagent includes phosphatidylethanolamine coupled to a 3-20 atom carbon-containing spacer arm terminating at a carboxyl or thiocarboxyl group. Also disclosed are liposomes prepared to include between about 1 and 20 mole percent of the coupling reagent, and liposomes containing surface arrays of proteins attached to the liposomes through the coupling reagent.

Abstract: A method for transforming Cephalosporium and other lower eukaryotes is disclosed. The method involves inserting a recombinant DNA cloning vector comprising a Saccharomyces cerevisiae transcriptional and translational activating sequence positioned for expression of hygromycin phosphotransferase into a host cell and then growing the host cell under selective conditions. The vectors optionally further comprise Cephalosporium ribosomal DNA and also sequences that allow for replication and selection in E. coli and Streptomyces.

Abstract: This invention is directed to the production of plants, plant tissues and plant seeds which are resistant to inhibition by an herbicide which normally inhibits the growth and development of those plants, plant tissues and plant seeds. In particular this invention is directed to altered acetohydroxyacid synthase enzymes which are resistant to inhibition by herbicides which normally inhibit the activity of the synthase before such alteration. This invention further relates to genes encoding such enzymes, and to processes for utilizing these novel genes and enzymes. Further products of the invention include plants, plant tissues and seeds which exhibit resistance to such herbicides resulting from expression of genes encoding herbicide resistant acetohydroxyacid synthase enzyme.

Abstract: Insulin receptor is purified in accordance with this invention to a level sufficient to enable amino acid sequencing thereof. DNA encoding insulin receptor is provided, as well as methods for synthesizing insulin receptor or its mutant in heterologous host cells transformed with vectors containing such DNA. Knowledge of the amino acid sequence for insulin receptor enables the preparation of novel immunogenic conjugates and antibodies raised against such conjugates. Novel therapeutically useful forms of the insulin receptor and anti-receptor antibodies are described.

Abstract: Plasmids which are in themselves unstably inherited or which have become unstable due to the insertion of a DNA fragment comprising one or more genes not naturally related to the plasmid are stablized by means of a partitioning function exerted by a par region, especially a plasmid R1 par region, inserted into the plasmid on a DNA fragment which may be the length of the wild-type R1 EcoR1-. A fragment, but which is preferably shorter than this fragment, and which may comprise the R1 par region A, the R1 par region B or both these R1 par regions. The stabilization obtained for several different types of plasmid, especially by employing both R1 par regions, approaches the stability level of wild-type plasmids, i.e. they typically have a frequency of loss of less than 5.times.10.sup.31 6 per cell per generation.

Abstract: Genes and DNA transfer vectors for the expression of human preprorelaxin; sub-units thereof, including genes and transfer vectors for expression of human prorelaxin and the individual A, B and C peptide chains thereof; and equivalents of all such genes. Methods for synthesis of the peptides involving recombinant DNA techniques.

Abstract: Plasmid vectors are provided that carry complementary DNA (cDNA) clones coding for polypeptides exhibiting mammalian IgE binding factor activity. One of these clones contains an open reading frame consisting of 556 codons. The cDNA is derived from messenger RNA isolated from a rat/mouse T-cell hybridoma line. The cDNA was cloned by incorporation into a pcD plasmid vector. The plasmid vector also contains DNA segments from the SV40 virus, permitting expression of the cDNA to form a polypeptide having IgE potentiating activity after transfection into a mammalian host cell, such as monkey Cos7 cells.

Abstract: A recombinant DNA molecule comprising a plasmid vector having operationally inserted therein a gene coding for phosphoenol pyruvate carboxylase is disclosed along with bacteria containing this recombinant DNA molecule and methods of using these bacteria to produce amino acids in large quantities.

Abstract: Methods and compositions are provided for regulated expression and secretion of polypeptides in transformed bacterial hosts. A novel class of plasmid cloning vehicles includes a DNA sequence coding for the desired polypeptide (or an insertion site therefor) linked for transcriptional expression in reading phase with four functional fragments derived from the lipoprotein gene of E. coli. The plasmids also include a DNA fragment coding for the signal peptide of the ompA protein of E. coli, positioned such that the desired polypeptide is expressed with the ompA signal peptide at its amino terminus, thereby allowing efficient secretion across the cytoplasmic membrane. The plasmids further include a DNA sequence coding for a specific segment of the E. coli lac promoter-operator, which is positioned in the proper orientation for transcriptional expression of the desired polypeptide, as well as a separate functional E.