Abstract: The present invention is directed to a gene which is related to a D-N-carbamoyl-.alpha.-amino acid amidohydrolase which is an enzyme capable of converting D-N-carbamoyl-.alpha.-amino acids into D-.alpha.-amino acids; a recombinant plasmid in which a DNA fragment containing the gene is incorporated into a vector; a microorganism belonging to the genus Escherichia, Pseudomonas, Flavobacterium, Bacillus, Serratia, Corynebacterium, or Brevibacterium, which is transformed by incorporating the recombinant plasmid thereinto; a process for the production of D-N-carbamoyl-.alpha.-amino acid amidohydrolases, comprising the steps of cultivating the transformed microorganism and collecting the desired product therefrom; a D-N-carbamoyl-.alpha.-amino acid amidohydrolase obtained by the method; and a process for the production of D-.alpha.-amino acids with the aid of an action of the enzyme.The D-N-carbamoyl-.alpha.-amino acid amidohydrolase can be fixed on a support for immobilization and used as an immobilized enzyme.

Abstract: A chromosomal DNA sequence which codes for human lymphotoxin, a lymphotoxin expression vector which contains a DNA sequence wherein a chromosomal DNA sequence coding for human lymphotoxin and promoter region which functions in animal cell are linked together, lymphotoxin resistant cell line, transformed animal cell culture which is formed by transforming cultured animal cell with a lymphotoxin expression vector which contains a chromosomal DNA sequence coding for human lymphotoxin and, a process for preparing human lymphotoxin, which comprises transforming cultured animal cell with a lymphotoxin expression vector which contains a chromosomal DNA sequence coding for human lymphotoxin, culturing the transformed cell culture to produce human lymphotoxin, and collecting the human lymphotoxin.According to the present invention, LT which is expected for application as the antitumor agent can be produced effectively in a large amount.