S U M M A R YL-Asparaginase and L-glutaminase activities were detected in many microorganisms and the distribution of these activities was found to be related to the classification of micro-organisms.Among 464 bacteria, the activities occurred in many Gram-negative bacteria and in a few Gram-positive bacteria. Most members of the family Enterobacteriaceae possessed L-asparaginase. L-Asparaginase and L-glutaminase occurred together in a large proportion of pseudomonads. Among Gram-positive bacteria many strains of Bacillus pumilus showed strong L-asparaginase activity. Amidase activities were also observed in several strains in other families.L-Asparaginase activity was not detected in culture filtrates of 261 strains of species of the genera Streptomyces and Nocardia, but L-asparaginase and Lglutaminase were detected when these organisms were sonicated.The amidase activities in culture filtrates of 4158 fungal strains were tested. All the strains of Fusarium species formed L-asparaginase. Organisms of the genera Hjyomyces and Nectria, which are regarded as the perfect stage of the genus Fusarium, also formed L-asparaginase. Several Penicillium species formed L-asparaginase. Two organisms of the family Moniliaceae formed L-glutaminase together with L-asparaginase, and a few ascomycetous fungi formed L-asparaginase or L-glutaminase.Among I 326 yeasts, L-asparaginase or L-glutaminase occurred frequently in certain serological groups of yeasts : VI (Hansenula) group, Cryptococcus group and Rhodotorula group. Many strains of Sporobolomyces species also showed L-asparaginase activity. Several strains of Cryptococcus and Rhodotorula group possessed L-glutaminase and L-asparaginase. L-Glutaminase alone was formed in many strains of Candida scottii and Cryptococcus albidus, both of which are related to Basidiomycetes.

The gene encoding an extracellular metalloproteinase from Serratia sp. E-15 has been cloned, and its complete nucleotide sequence determined. The amino acid sequence deduced from the nucleotide sequence reveals that the mature protein of the Serratia protease consists of 470 amino acids with a molecular weight of 50,632. The G+C content of the coding region for the mature protein is 58%; this high G+C content is due to a marked preference for G+C bases at the third position of the codons. The gene codes for a short pro-peptide preceding the mature protein. The Serratia protease gene was expressed in Escherichia coli and Serratia marcescens; the former produced the Serratia protease in the cells and the latter in the culture medium. Three zinc ligands and an active site of the Serratia protease were predicted by comparing the structure of the enzyme with those of thermolysin and Bacillus subtilis neutral protease.

A cDNA encoding a novel human neurotrophic factor (designated nerve growth factor‐2; NGF‐2) was cloned from a human glioma cDNA library using a synthetic DNA corresponding to human nerve growth factor (NGF). The cloned cDNA encodes a polypeptide composed of 257 amino acid residues including a prepro‐sequence of 138 residues and a mature region of 119 residues. The amino acid sequence of human NGF‐2 exhibits 58% similarity with that of human NGF. Conditioned medium of COS‐7 cells transfected with an expression plasmid for human NGF‐2 cDNA supported the survival of sensory neurons isolated from dorsal root ganglia of embryonic chicks. A 1.5 kb of NGF‐2 mRNA can be detected from an early development stage in rat brain, by Northern blotting analysis.

Using previously isolated Bacillus brevis strains that secrete large amounts of proteins but little protease into the medium, we have developed a host-vector system for very efficient synthesis and secretion of heterologous proteins. The multiple promoters and the signal-peptide-coding region of the MWP gene, a structural gene for one of the major cell wall proteins of B. brevis strain 47, were used to construct expression-secretion vectors. With this system, a synthetic gene for human epidermal growth factor (hEGF) was expressed efficiently and a large amount (0.24 g per liter ofculture) of mature hEGF was secreted into the medium. hEGF purified from the culture supernatant had the same NH2-terminal amino acid sequence, COOH-terminal amino acid, and amino acid composition as natural hEGF, and it was fully active in biological assays. These results, in combination with previous results, showed that mammalian proteins can be produced in active form 10-100 times more efficiently in B. brevis than has been reported in other systems.

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