Coryneform bacterium transformant and process for producing phenol using the same
Provided is a phenol-producing transformant constructed by transferring a gene which encodes an enzyme having chorismate-pyruvate lyase activity and a gene which encodes an enzyme having 4-hydroxybenzoate decarboxylase activity into a coryneform bacterium as a host. Also provided is a process for producing phenol, which comprises a step of allowing the transformant to react in a reaction mixture containing a saccharide under reducing conditions, and a step of collecting phenol from the reaction mixture.
1. A phenol-producing transformant, wherein the phenol-producing transformant is a Corynebacterium transformed with a Pantoea ananatis chorismate-pyruvate lyase gene and an Enterobacter cloacae 4-hydroxybenzoate decarboxylase gene.
2. The phenol-producing transformant of claim 1 , wherein the Pantoea ananatis chorismate-pyruvate lyase gene consists of the nucleotide sequence of SEQ ID NO: 89.
3. The phenol-producing transformant of claim 1 , wherein the Enterobacter cloacae 4-hydroxybenzoate decarboxylase gene consists of the nucleotide sequence of SEQ ID NO: 56.
4. The phenol-producing transformant of claim 1 , wherein a 4-hydroxybenzoate hydroxylase gene on the chromosome of the Corynebacterium is disrupted or deleted.
5. The phenol-producing transformant of claim 1 , wherein a phenol 2-monooxygenase gene on the chromosome of the Corynebacterium is disrupted or deleted.
6. The phenol-producing transformant of claim 1 , wherein the Corynebacterium is a Corynebacterium glutamicum.
7. The phenol-producing transformant of claim 1 , wherein the Corynebacterium is Corynebacterium glutamicum R having accession number FERM BP-18976, ATCC13032, or ATCC13869.
8. The phenol-producing transformant of claim 7 , wherein the Corynebacterium is Corynebacterium glutamicum R having accession number FERM BP-18976, or ATCC13032 or ATCC13869, and wherein a 4-hydroxybenzoate hydroxylase gene on the chromosome of the Corynebacterium glutamicum is disrupted or deleted.
9. The phenol-producing transformant of claim 7 , wherein the Corynebacterium is Corynebacterium glutamicum R having accession number FERM BP-18976, or ATCC13032 or ATCC13869, and wherein a phenol 2-monooxygenase gene on the chromosome of the Corynebacterium glutamicum is disrupted or deleted.
10. A process for producing phenol, which comprises reacting the phenol-producing transformant of claim 1 with a saccharide in a reaction mixture under reducing conditions to produce phenol, and collecting phenol from the reaction mixture.
11. The process of claim 10 , wherein the phenol-producing transformant does not proliferate in the reacting step.
12. The process of claim 10 , wherein the oxidation-reduction potential of the reaction mixture under reducing conditions is −200 mV to −500 mV.
13. The process of claim 10 , wherein the saccharide is selected from the group consisting of glucose, fructose, mannose, xylose, arabinose, galactose, sucrose, maltose, lactose, cellobiose, xylobiose, trehalose, and mannitol.
14. The phenol-producing transformant of claim 1 , wherein expression of a Corynebacterium aroG gene which encodes an enzyme having 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase activity is increased in the phenol-producing transformant as compared with a corresponding wild-type Corynebacterium.