摘要:
Described herein is a bacterial cell containing a recombinant bacteriophage defense mechanism. The defense mechanism comprises a bacteriophage promoter (e.g., a phage .phi.31 promoter; a T7 promoter) operatively associated with a heterologous DNA encoding a product lethal to the bacterial cell. The bacterial cell is susceptible to infection by a bacteriophage, and the promoter is activated upon the infection of said bacterial cell by that bacteriophage. Bacteria useful in carrying out the invention include both gram negative and gram positive bacteria (e.g., Lactococcus lactis; Escherichia coli); the heterologous DNA may encode an enzyme that degrades nucleic acid (e.g., the products of the LlaI restriction cassette; barnase). Recombinant DNAs useful for making the foregoing cells, cultures prepared from such cells, and fermentation methods carried out with such cells are also disclosed.
摘要:
An enzyme from Aspergillus aculeatus exhibiting endoglucanase activity, which enzyme is designated EG II or EG IV and is encoded by a DNA sequence comprising at least one of the partial sequences shown in SEQ ID NO: 17, 18, or 19. The enzyme may be produced by recombinant DNA techniques and may be used for degradation of plant cell wall material.
摘要:
A transformant, which harbors a recombinant vector containing a DNA which codes for human nerve growth factor 2 and a DNA which codes for the pro-region of a nerve growth factor at 5'-terminal of said DNA, produces human nerve factor 2 in stable and large amount in a culture medium.