JPH0431672B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing L-amino acids from 5-substituted hydantoins using a microbial enzyme system. [Prior art] Regarding the production of L-amino acids from 5-substituted hydantoins using microbial enzyme systems, examples using various microbial sources have been known (Tokuko Sho et al.
42-13850, 54-2274, and 54-8749). However, each of these methods cannot be said to be fully satisfactory. [Object of the Invention] An object of the present invention is to provide a method for producing the corresponding L-amino acid from a 5-substituted hydantoin more efficiently using a microbial enzyme system. [Structure of the Invention] To summarize the present invention, the present invention relates to a method for producing L-phenylalanine, L-tryptophan, or L-tyrosine, and the present invention relates to a method for producing L-phenylalanine, L-tryptophan, or L-tyrosine, wherein , L-tryptophan, and L-tyrosine by reacting the culture solution, strain, or bacterial cell treatment product of the DK-200 strain of the genus Arilobacter with the 5-substituted hydantoin, and producing the corresponding L-phenol. It is characterized by collecting enylalanine, L-tryptophan, or L-tyrosine. Arilobacter genus DK- used in the present invention
Strain 200 is a new strain newly isolated by the present inventors, and its mycological properties are shown below. 1 Morphology (1) Cell shape and size: 0.3 to 0.5 x 0.8 to 5.0 μm (2) Presence or absence of pleomorphism: Yes (3) Presence or absence of motility: No (4) Presence or absence of flagella, epiphytic state No (5) Presence or absence of spores: None (6) Gram staining:
Negative to weakly positive, but has Gram-positive particles (7) Acid-fast: None 2 Growth status in each medium (1) Broth agar plate culture Colony color: Pale white Colony shape: Round Colony protuberance: Convex Colony Peripheral edge: Entire edge (2) Meat juice agar slant culture Growth condition: Moderate Gloss: Yes Shape: Thread-like (3) Meat juice liquid culture Degree of turbidity: Uniform Precipitation: Yes Growth on liquid surface: None in particular (4) Meat juice gelatin puncture Culture: Liquefaction 3 Physiological properties (1) Nitrate reduction: Yin (2) Denitrification reaction: Yin (3) MR test: Yin (4) VP test: Yin (5) Indole production: Yin (6) Sulfidation Production of hydrogen: Yin (7) Hydrolysis of starch: Yin (8) Utilization of citric acid:
Do not use Koser medium and Christensen medium together (9) Use of inorganic nitrogen source:
Combines use of nitrate and ammonium salts (10) Pigment production: None (11)ase: Yin (12)dase: Yin (13)ase: Attitude towards light (14): Aerobic (15) Growth range Temperature : 17.8~33.2℃ pH: 5~10 (16) OF test: Oxidative (17) Presence or absence of acid and gas generation from sugars

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. In addition, unless otherwise specified, % in each example is weight %. Example 1 Glucose 0.5%, yeast extract 0.2%, disodium hydrogen phosphate 0.1%, potassium dihydrogen phosphate
A medium (pH 7.5) containing 0.05% magnesium sulfate and 0.05% magnesium sulfate was dispensed into test tubes and sterilized at 120°C for 15 minutes. After separately sterilized DL-N-carbamyltryptophan was added to the final concentration of 0.05%, Arilobacter DK-200 was inoculated and cultured with shaking at 30°C for 24 hours. Each of the 5-substituted hydantoins listed in Table 1 below was added to this culture solution, and each was further incubated at 30°C for 24 hours.
Continue shaking for an hour. After the reaction, bacteria were removed by centrifugation, and the amino acids in the supernatant were analyzed using HPLC and bioassay (Lactobacillus arabinozas).
Quantitative analysis using ATCC 8014) showed that the values matched, so it was confirmed to be an L-amino acid.

[Table] Example 2 Glucose 0.5%, yeast extract 0.2%, disodium hydrogen phosphate 0.1%, potassium dihydrogen phosphate
Medium containing 0.05% magnesium sulfate, 0.05% magnesium sulfate, and 0.1% DL-indolylmethylhydantoin (pH 7.5)
100 ml of the mixture was placed in a 500 ml flask and sterilized at 120°C for 15 minutes. This includes 0.5% glucose and 0.5% yeast extract.
%, 0.5% polypeptone, and 0.5% sodium chloride (pH 7.5) was inoculated with 5 ml of a seed culture cultured at 30°C for 20 hours, and cultured at 30°C for 24 hours. After this culture, the bacterial cells were centrifuged from the culture solution and washed once with physiological saline. This bacterial cell was mixed with 0.2M of DL-5-benzylhydantoin and 0.5mM of cobalt chloride.
100 ml of 0.1 M Tris-HCl buffer (pH 7.0) containing
and reacted at 35°C for 65 hours. After the reaction, bacteria were removed by centrifugation, and the supernatant was concentrated to 20 ml and cooled to obtain crystals. This crystal,
As a result of TLC, HPLC, NMR, and optical rotation analysis, it was confirmed that the product corresponded to the L-phenylalanine standard as shown in Table 2 below.

〔Effect of the invention〕

As explained above, according to the present invention, Arylobacter genus DK-
Using 200 bacteria, the corresponding L-amino acid could be efficiently produced.

Claims (1)

[Claims] 1 Arilobacter species capable of converting 5-substituted hydantoins to the corresponding L-phenylalanine, L-tryptophan, and L-tyrosine
DK-200 strain culture solution, strain or treated bacterial cells,
A method for producing L-amino acids, which comprises reacting a 5-substituted hydantoin and collecting the corresponding L-phenylalanine, L-tryptophan, or L-tyrosine produced.