摘要:
The invention relates to a process for producing outer membrane proteins of gram-negative bacteria by gram-positive host cells. To this end, a gene structure containing a gene coded for an outer membrane protein is constructed; in front of this gene there is a pro-gene sequence which codes for a propeptide of an export protein of a gram-positive bacterium. In front of the pro-gene sequence there is a pre-gene sequence which codes for a signal peptide of an export protein of a gram-positive bacterium. After the cloning of a gene structure thus constructed into a vector and transformation into a gram-positive bacterium, the outer membrane protein is expressed with a signal peptide and propeptide, transported through the membrane of the gram-positive host cell and released into the test of the culture.
摘要:
This invention relates to the nucleotide sequence of coryneform bacteria coding for proteins which are involved in L-serine metabolism with reduced and switched off L-serine dehydratase activity. The invention also relates to microorganisms used in methods for producing L-serine.
摘要:
L-lysine-producing strains of corynebacteria with enhanced lysE gene (lysine export carrier gene), in which strains additional genes chosen from the group comprising the dapA gene (dihydrodipicolinate synthase gene), the lysC gene (aspartate kinase gene), the dapB gene (dihydrodipicolinate reductase gene) and the pyc gene, but especially the dapA gene and the lysC gene (aspartate kinase gene), are enhanced and, in particular, over-expressed, and to a process for the preparation of L-lysine.
摘要:
The invention relates to a method for producing L-valine and to a suitable microorganism. The inventive method is characterized by preferably enhancing the transaminase C activity of a coryneform bacterium, especially Corynebacteriuim glutamicum. The organisms so modified have a yield in L-valine which is 35.8% higher than that of non-modified organisms.
摘要:
The invention relates to L-lysine-producing strains of corynebacteria with enhanced lysE gene (lysine export carrier gene), in which strains additional genes chosen from the group comprising the dapA gene (dihydrodipicolinate synthase gene), the lysC gene (aspartate kinase gene), the dapB gene (dihydrodipicolinate reductase gene) and the pyc gene, but especially the dapA gene and the lysC gene (aspartate kinase gene), are enhanced and, in particular, over-expressed, and to a process for the preparation of L-lysine.
摘要:
The invention relates to L-lysine-producing strains of corynebacteria with enhanced lysE gene (lysine export carrier gene), in which strains additional genes chosen from the group comprising the dapA gene (dihydrodipicolinate synthase gene), the lysC gene (aspartate kinase gene), the dapB gene (dihydrodipicolinate reductase gene) and the pyc gene, but especially the dapA gene and the lysC gene (aspartate kinase gene), are enhanced and, in particular, over-expressed, and to a process for the preparation of L-lysine.
摘要:
The invention relates to preferably recombinant DNA derived from Corynebacterium and replicable in coryneform microorganisms, which contains at least one nucleotide sequence that codes for the thrE gene, and a process for the production of L-threonine, which is characterised in that the following steps are carried out: a) Fermentation of microorganisms in which at least the thrE gene is amplified (overexpressed), optionally in combination with further genes, b) Enrichment of the L-threonine in the medium or in the cells of the microorganisms, and c) Isolation of the L-threonine.
摘要:
This invention relates to a genetically modified coryneform bacterium, the cls gene of which is amplified, and to an isolated polynucleotide, which codes for cardiolipin synthase from coryneform bacteria and to a process for the fermentative production of L-amino acids with amplification of the cls gene in the bacteria and to the use of the polynucleotide as a primer or hybridization probe.
摘要:
The invention relates to processes for the microbial production of L-isoleucine. To this end, in a gene in vitro of a threonine dehydratse, one or more bases in the gene region coding the enzyme's allosteric domains are exchanged in such a way that at least one amino acid in the amino acid sequence of the allosteric domains of the enzyme is replaced by another so that the enzyme is no longer inhibited by L-isoleucine feedback. Furthermore, concrete amino acid exchanges in the amino acid sequence of the enzyme are effected in a gene in vitro of a threonin dehydratase of Corynebacterium glutamicum by base exchange both outside and inside and outside the gene region coding the allosteric domains of the enzyme si that, after the transformation of such mutated threonine dehydratase genes into a threonine or L-isoleucine-producing host cell, the latter repeatedly forms L-isoleucine.
摘要:
The long-term activity of the biocatalyst for the production of sorbitol and gluconic acid from an aqueous solution of fructose and glucose is considerably improved with the aid of permeabilized cells of Zymomonas mobilis immobilized using .kappa.-carrageenan that has been rigidified and then stabilized by K.sup.+ ions. Rigidification of .kappa.-carrageenan is preferably carried out by treatment with glutaraldehyde alone or by treatment with polyethyleneimine or hexamethylenediamine and subsequent exposure to glutaraldehyde. A buffer-free solution is preferred and the pH is maintained by adding Ca.sup.++ ions while simultaneously precipitating gluconic acid.