Coryneform bacterium transformant and process for producing phenol using the same
A phenol-producing transformant is provided which can efficiently produce phenol from a saccharide. A gene which encodes an enzyme having tyrosine phenol-lyase activity is transferred into Corynebacterium glutamicum as a host. A process for producing phenol is provided having a step of reacting the transformant 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 constructed by transferring a gene which encodes an enzyme having tyrosine phenol-lyase activity into a Corynebacterium as a host,
wherein the gene which encodes an enzyme having tyrosine phenol-lyase activity is a DNA consisting of the nucleotide sequence of SEQ ID NO: 36, SEQ ID NO: 39, SEQ ID NO: 42, SEQ ID NO: 45, SEQ ID NO: 48 or SEQ ID NO: 51;
a gene which encodes an enzyme having DAHP (3-deoxy-D-arabino-heptulosonate 7-phosphate) synthase activity aroG of the Cornybacterium and a gene which encodes an enzyme having chorismate mutase activity of the Cornyebacterium as the host are highly expressed, and
a gene which encodes an enzyme having prephenate dehydratase activity on the chromosome of the Cornyebacterium as the host is disrupted or deleted.
2. The transformant of claim 1 , wherein a gene which encodes an enzyme having phenol 2-monooxygenase activity on the chromosome of the Cornyebacterium as the host has a disruption or deletion.
3. The transformant of claim 1 , wherein the Cornyebacterium as the host is Corynebacterium glutamicum ,
the gene which encodes the enzyme having DAHP (3-deoxy-D-arabino-heptulosonate 7-phosphate) synthase activity aroG of the Corynebacterium glutamicum and the gene which encodes the enzyme having chorismate mutase activity of Corynebacterium glutamicum R (FERM BP-18976), ATCC13032, or ATCC13869 as the host are highly expressed, and
the gene which encodes the enzyme having prephenate dehydratase activity on the chromosome of Corynebacterium glutamicum R (FERM BP-18976), ATCC13032, or ATCC13869 as the host Corynebacterium glutamicum is disrupted or deleted.
4. A Corynebacterium glutamicum transformant PHE7 (Accession Number: NITE BP-976).
5. A process for producing phenol, which comprises a step of reacting the transformant of claim 1 in a reaction mixture containing a saccharide under reducing conditions, and a step of collecting phenol from the reaction mixture.
6. The process of claim 5 , wherein the transformant does not substantially proliferate in the reaction step.
7. The process of claim 5 , wherein the oxidation-reduction potential of the reaction mixture under reducing conditions is −200 mV to −500 mV.
8. The process of claim 5 , wherein the saccharide is selected from a group consisting of glucose, fructose, mannose, xylose, arabinose, galactose, sucrose, maltose, lactose, cellobiose, trehalose, and mannitol.