| 摘要 |
Coryneform bacterium mutant comprises a gene coding for a 2-methylcitrate dehydratase polypeptide (I) with a proteinogenic amino acid other than L-proline at position 272. Independent claims are also included for: (1) coryneform bacterium mutant produced by treating a coryneform bacterium with a mutagenic agent, isolating and multiplying the resulting mutants, preparing nucleic acids from the mutants, producing a nucleic acid molecule from the nucleic acids by PCR using a primer comprising at least 15 consecutive nucleotides from the sequence between positions 1 and 1563 of SEQ ID NO:3 or SEQ ID NO:7 (not given in the specification) and a primer comprising at least 15 consecutive nucleotides from the complementary sequence between positions 3000 and 1567 of SEQ ID NO:3 or SEQ ID NO:7, sequencing the nucleic acid molecule and determining the encoded amino acid sequence, optionally comparing the sequence with SEQ ID NO:6 (not given in the specification), and identifying a mutant containing a polynucleotide coding for a polypeptide with a proteinogenic amino acid other than L-proline at position 272; (2) isolated polynucleotide (II) coding for (I); (3) isolated polynucleotide coding for an amino acid sequence corresponding to positions 19-57 of SEQ ID NO:2 (not given in the specification) with a proteinogenic amino acid other than L-proline at position 272; (4) producing a recombinant coryneform bacterium by transferring (II) into a coryneform bacterium so that the bacterium's 2-methylcitrate dehydratase gene is replaced by (II) and multiplying the resulting bacterium; (5) producing a recombinant microorganism by transferring (II) into a microorganism, replicating (II) in the microorganism and multiplying the resulting microorganism; (6) recombinant microorganism containing (II); (7) vector containing (II); (8) recombinant microorganism containing the vector; (9) producing a L-amino acid by culturing a coryneform bacterium mutant as above so that the L-amino acid is enriched in the culture broth or in the bacterial cells; (10) animal feed additive based on a culture broth, with a lysine content of 10-73 wt.%, a water content of up to 5 wt.% and a biomass content that is at least 0.1% of the biomass in the culture broth, where the biomass is derived from a bacterium as above; (11) animal feed additive based on a culture broth, with a tryptophan content of at least 5 wt.%, a water content of up to 5 wt.% and a biomass content that is at least 0.1% of the biomass in the culture broth, where the biomass is derived from a bacterium as above. |
