摘要:
A method of producing L-threonine using a microorganism is provided, one or more copies of each of the phosphoenolpyruvate carboxylase gene and the threonine operon are additionally intedgrated into a particular site of the chromosomal DNA of the microorganism, whiel its inherent phophoenolpyruvate carboxylase gene and threonine operon remain.
摘要:
A method for producing L-threonine using a microorganism is provided. In the method, additional one or more copies of each of the phosphoenolpyruvate carboxylase (ppc) gene and the threonine operon are integrated into a particular site of the chromosomal DNA of a microorganism, while its inherent ppc gene and threonine operon remain. Accordingly, two or more ppc genes and threonine operons are included in the chromosomal DNA of the microorganism to thereby enhance the expression of the ppc gene encoding an enzyme to convert phosphoenolpyruvate to a threonine biosynthesis precursor, oxaloacetete, and the genes encoding enzymes involved in the synthetic pathway of threonine from oxaloacetate, including thrA (aspartokinasel-homoserine dehydrogenase), thrB (homoserine kinase), and thrC (threonine synthase), thereby markedly increasing L-threonine productivity.
摘要:
The present invention relates to a vaccine prepared from an attenuated Pseudomonas aeruginosa strains which are obtained by isolating Pseudomonas aeruginosa in a pure state according to the Fisher-Devlin immunotype and then repeatedly purifying the isolated strain, particularly CFCPA 10142 (KCCM 10029), CFCPA 20215 (KCCM 10030), CFCPA 30720 (KCCM 10031), CFCPA 40057 (KCCM 10032), CFCPA 50243 (KCCM 10033), CFCPA 60534 (KCCM 10034) and CFCPA 70018 (KCCM 10035) strains. In addition, the present invention relates to a process for preparing the vaccine for immunization against Pseudomonas aeruginosa infection which contains cell wall proteins having molecular weights ranging from 10,000 to 100,000. The cell wall protein component of the attenuated strain is non-pathogenic and safe, and exhibits excellent antibody formation capacity and is useful for preparation of a vaccine and therapeutic agent. The cell wall proteins exhibit an excellent cross-protective efficacy for various Pseudomonas aeruginosa strains and a superior antibody inducing property.
摘要:
A method for producing L-threonine using a microorganism is provided. In the method, additional one or more copies of each of the phosphoenolpyruvate carboxylase (ppc) gene and the threonine operon are integrated into a particular site of the chromosomal DNA of a microorganism, while its inherent ppc gene and threonine operon remain. Accordingly, two or more ppc genes and threonine operons are included in the chromosomal DNA of the microorganism to thereby enhance the expression of the ppc gene encoding an enzyme to convert phosphoenolpyruvate to a threonine biosynthesis precursor, oxaloacetete, and the genes encoding enzymes involved in the synthetic pathway of threonine from oxaloacetate, including thrA (aspartokinasel-homoserine dehydrogenase), thrB (homoserine kinase), and thrC (threonine synthase), thereby markedly increasing L-threonine productivity.