Industrially Useful Microorganism
The present invention provides a microorganism which comprises a chromosomal DNA lacking a part or entire of the gene encoding a protein having the amino acid sequence as shown in SEQ ID NO: 1 or 2, or the gene encoding a protein having 80% or more homology with the amino acid sequence as shown in SEQ ID NO: 1 or 2, and has the ability to produce a useful substance; a process for producing a useful substance using said strain; especially a process for producing a useful substance which is selected from the group consisting of proteins, peptides, amino acids, nucleic acids, vitamins, saccharides, organic acids, and lipids.
1 . A microorganism which comprises chromosomal DNA lacking a part or entire of the gene encoding a protein having the amino acid sequence as shown in at least one of SEQ ID NOs: 1 and 2 and/or the gene encoding a protein having 80% or more homology with the amino acid sequence as shown in at least one of SEQ ID NOs: 1 and 2, and which is capable of producing a useful substance.
2 . The microorganism according to claim 1 , wherein the gene encoding a protein having the amino acid sequence as shown in SEQ ID NO: 1 or 2 has the nucleotide sequence as shown in SEQ ID NO: 3 or 4, respectively.
3 . The microorganism according to claim 1 , wherein the ability to produce a useful substance is enhanced by a method selected from among the following [1] to [5]:
[1] a method for reducing or removing at least one mechanism for regulating biosynthesis of the useful substance;
[2] a method for increasing the expression level of at least one enzyme associated with biosynthesis of the useful substance;
[3] a method for increasing the copy number of at least one enzyme gene associated with biosynthesis of the useful substance;
[4] a method for attenuating or blocking at least one metabolic pathway which branches from the biosynthetic pathway of the useful substance into metabolites other than the useful substance; or
[5] a method for selecting a strain that exhibits higher resistance to an analogue of a useful substance than a wild-type strain.
4 . The microorganism according to claim 3 , which belongs to the genus Erwinia, Serratia, Salmonella, Escherichia, Proteus, Pseudomonas, or Xanthomonas.
5 . The microorganism according to claim 4 , which is selected from the group consisting of Erwinia berbicola, Erwinia amylovora, Erwinia carotovora, Serratia marcescens, Serratia ficaria, Serratia fonticola, Serratia liquefaciens, Salmonella typhimurium, Escherichia coli, Proteus rettgeri, Pseudomonas putida, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas dacunhae, Pseudomonas thazdinophtlum, Xanthomonas oryzae, and Xanthomonas capestris.
6 . A process for producing a useful substance which comprises culturing the microorganism according to claim 5 in a medium so as to form and accumulate the useful substance in the culture product and recovering the useful substances from the culture product.
7 . The process according to claim 6 , wherein the useful substance is selected from the group consisting of proteins, peptides, amino acids, nucleic acids, vitamins, saccharides, organic acids, and lipids.
8 . The microorganism according to claim 3 , wherein the gene encoding a protein having the amino acid sequence as shown in SEQ ID NO: 1 or 2 has the nucleotide sequence as shown in SEQ ID NO: 3 or 4, respectively.
9 . The microorganism according to claim 8 , which belongs to the genus Erwinia, Serratia, Salmonella, Escherichia, Proteus, Pseudomonas, or Xanthomonas.
10 . The microorganism according to claim 9 , which is selected from the group consisting of Erwinia berbicola, Erwinia amylovora, Erwinia carotovora, Serratia marcescens, Serratia ficaria, Serratia fonticola, Serratia liquefaciens, Salmonella typhimurium, Escherichia coli, Proteus rettgeri, Pseudomonas putida, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas dacunhae, Pseudomonas thazdinophtlum, Xanthomonas oryzae, and Xanthomonas capestris.
11 . A process for producing a useful substance which comprises culturing the microorganism according to claim 10 in a medium so as to form and accumulate the useful substance in the culture product and recovering the useful substances from the culture product.
12 . The process according to claim 11 , wherein the useful substance is selected from the group consisting of proteins, peptides, amino acids, nucleic acids, vitamins, saccharides, organic acids, and lipids.