Abstract: Nucleotide sequences capable of inducing high levels of translation of a heterologous gene in Bacillus subtilis and Escherichia coli and a method of preparing heterologous proteins comprising cultivation in a suitable culture medium of cells of Bacillus subtilis and Escherichia coli transformed by hybrid plasmids in which the nucleotide sequence is situated between the ribosome recognition site and the starting triplet (ATG) of the coding structural gene for the desired proteins.

Abstract: A method is provided for expressing the proteases dipeptidyl aminopeptidases A and B which are useful for processing precursor proteins. Genes controlling these proteases may be insdrted into appropriate vectors and transformed into cultures. The proteases may either be utilized to process precursor proteins in vivo or may be extracted from cultures and used to process precursor proteins in vitro.

Abstract: A purified fibrinolytically active degraded species of tissue-type plasminogen activator comprising a fibrinolytically intact B chain of native t-PA linked to kringle 2 as the only functionally and structurally intact domain of native t-PA A chain.

Abstract: A modified tissue plasminogen activator having an improved in vivo half-life characterized in that the normal protein moiety of 527 amino acids is mutated at the site Cys73.fwdarw.Arg.

Abstract: Two new bacterial strains designated Zoogloea ramigera 115SL and Zoogloea ramigera 115SLR, a rifampicin resistant derivative of 115SL, have been developed. These strains are derived from the wild type Zoogloea ramigera 115, ATCC 25935. The two new strains produce a novel exopolysaccharide (EPS) and have several desirable characteristics that are absent from the parent strain, including improved culture properties, since they do not produce an EPS capsule layer like that of the parent 115 strain. The 115SL EPS is instead excreted as a slime layer which is not confined to the immediate area surrounding the cells. Since cells are not trapped within a floc where they grow at a reduced rate or die because of nutrient starvation, the new strains have more consistent and reproducible growth cycles and increased growth rates. As a consequence, exopolysaccharide production is more consistent and titers are higher. The separation of the EPS from the cells is also much easier and more economical.

Abstract: The present invention relates to a process for separating and purifying proteases and antiproteases. This process is characterized in that there are placed in contact an insoluble cross-linked polymer including in its chain the group --SO.sub.3 R.sub.1 -- and/or the group --SO.sub.2 R.sub.2 -- in which R.sub.1 denotes a hydrogen atom or metal and R.sub.2 denotes the remainder of an amino acid linked to the --SO.sub.2 -- bridge through its amine --NH--, function, with the solution containing proteases and antiproteases or their complex; separating the polymer which has absorbed the desired protein, washing it carefully with the buffer, desorbing the absorbed protein by a solution of a polycationic compound in the case of T or by an albumin solution in the case of AT or of the complex T-AT, and isolating the protein, if desired, by known means, such as, especially, freeze drying. The invention is useful for studying the mechanism of blood coagulation.