JP2003024094A - Method for producing 5'-guanylic acid - Google Patents

Method for producing 5'-guanylic acid

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Publication number
JP2003024094A
JP2003024094A JP2001209468A JP2001209468A JP2003024094A JP 2003024094 A JP2003024094 A JP 2003024094A JP 2001209468 A JP2001209468 A JP 2001209468A JP 2001209468 A JP2001209468 A JP 2001209468A JP 2003024094 A JP2003024094 A JP 2003024094A
Authority
JP
Japan
Prior art keywords
reaction
acid
guanosine
enzyme
guanylic acid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2001209468A
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Japanese (ja)
Other versions
JP4649787B2 (en
Inventor
Masayuki Araki
政行 荒木
Yoshiyuki Inuzuka
義之 犬塚
Iwao Iida
巌 飯田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ajinomoto Co Inc
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Ajinomoto Co Inc
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Priority to JP2001209468A priority Critical patent/JP4649787B2/en
Publication of JP2003024094A publication Critical patent/JP2003024094A/en
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Expired - Fee Related legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To provide a method for producing 5'-guanylic acid from guanosine and polymerized phosphoric acid, by which the production efficiency of the 5'-guanylic acid is improved. SOLUTION: This method for producing 5'-guanylic acid, comprising reacting guanosine with polymerized phosphoric acid in the presence of an enzyme catalyst such as acidic phosphatase to phosphorylate the guanosine, thus producing the 5'-guanylic acid, is characterized by performing an enzyme activity-lowering treatment such as the lowering of reaction temperature, the addition of an enzyme reaction inhibitor, the bubbling of a gas, or the like.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【発明の属する技術分野】本発明は、5’−グアニル酸
の製造法に関する。5’−グアニル酸は、調味料、医薬
並びにそれらの原料等として有用である。
TECHNICAL FIELD The present invention relates to a method for producing 5'-guanylic acid. 5'-guanylic acid is useful as a seasoning, a medicine, a raw material thereof, and the like.

【0002】[0002]

【従来の技術】グアノシンを酵素的にリン酸化して5’
−グアニル酸を製造する方法として、種々の方法が知ら
れている。中でも、副産物が少なく、かつ、効率のよい
5’−グアニル酸の製造法として、酸性フォスファター
ゼをpH3.0〜5.5の条件下でグアノシン等のヌクレオチ
ド、並びにポリリン酸(塩)、フェニルリン酸(塩)及
びカルバミルリン酸(塩)から成る群より選択されるリ
ン酸供与体に作用させて5’−グアニル酸等のヌクレオ
シド−5’−リン酸エステルを製造する方法が開発され
ている(WO96/37603、特開平10-201481)。また、これ
らの方法において、好ましい酸性フォスファターゼとし
て、リン酸エステル加水分解活性が低下した変異型酸性
フォスファターゼ(WO96/37603)、あるいは、ヌクレオ
シドに対する親和性が上昇し及び/又は温度安定性が向
上した変異型フォスファターゼ(特開平10-201481)が
提案されている。
2. Description of the Related Art 5'by enzymatically phosphorylating guanosine
-Various methods are known as methods for producing guanylic acid. Among them, as a method for efficiently producing 5'-guanylic acid with less by-products, acid phosphatase is used under conditions of pH 3.0 to 5.5, nucleotides such as guanosine, and polyphosphoric acid (salt) and phenylphosphoric acid (salt). ) And carbamyl phosphoric acid (salt), a method for producing a nucleoside-5′-phosphoric acid ester such as 5′-guanylic acid has been developed (WO96 / 37603). , JP-A-10-201481). Further, in these methods, as a preferred acid phosphatase, a mutant acid phosphatase with reduced phosphoric acid ester hydrolysis activity (WO96 / 37603), or a mutation with increased affinity for nucleoside and / or improved temperature stability A type phosphatase (Japanese Patent Laid-Open No. 10-201481) has been proposed.

【0003】上記の方法においては、グアノシンのよう
な難溶性のヌクレオシドを基質とする際、易溶性のヌク
レオシドに比べて反応収率が低下するという問題があっ
た。一方、難溶性のヌクレオシドであっても、有機溶
剤、硼酸あるいはジメチルスルホキシドのような界面活
性剤を反応系に添加することによって、ヌクレオシド−
5’−リン酸エステルの生成収率を向上させることがで
きる場合がある(WO96/37603, 特開平10-201481)。し
かし、一般的に有機溶剤や界面活性剤などにより極度の
酵素の失活が誘発される恐れがあり、好ましくない場合
も少なくないと考えられる。
In the above-mentioned method, when a poorly soluble nucleoside such as guanosine is used as a substrate, the reaction yield is lower than that of the easily soluble nucleoside. On the other hand, even with a sparingly soluble nucleoside, the addition of a surfactant such as an organic solvent, boric acid or dimethylsulfoxide to the reaction system can
In some cases, the production yield of 5'-phosphate ester can be improved (WO96 / 37603, JP-A-10-201481). However, in general, there is a possibility that an extreme inactivation of the enzyme may be induced by an organic solvent or a surfactant, and it is considered that there are many cases where this is not preferable.

【0004】[0004]

【発明が解決しようとする課題】本発明は、グアノシン
及び重合リン酸を用いて5’−グアニル酸を製造する方
法を改良し、5’−グアニル酸の生成効率を向上させる
手段を提供することを課題とする。
DISCLOSURE OF THE INVENTION The present invention provides a means for improving the method for producing 5'-guanylic acid using guanosine and polymerized phosphoric acid, thereby improving the production efficiency of 5'-guanylic acid. Is an issue.

【0005】[0005]

【課題を解決するための手段】本発明者は、上記課題を
解決するために鋭意研究を行った結果、グアノシン及び
重合リン酸を用いて酵素反応により5’−グアニル酸を
製造する際に、反応の進行に伴って難溶性であるグアノ
シンの表面積が低下し、前記酵素による重合リン酸の分
解反応が進行するために、反応速度が低下するのではな
いかと考えた。そして、グアノシンの表面積の低下に合
わせて酵素活性を低下させることによって、生成効率を
向上させることができると考え、反応中の酵素活性を低
下させたところ、5’−グアニル酸の生成効率が向上す
ることを見い出し、本発明を完成させるに至った。すな
わち本発明は、以下のとおりである。
Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that when guanosine and polymerized phosphoric acid are used to produce 5′-guanylic acid by an enzymatic reaction, It was considered that the surface area of the poorly soluble guanosine decreases with the progress of the reaction and the decomposition reaction of the polymerized phosphoric acid by the enzyme proceeds, so that the reaction rate may decrease. Then, it is thought that the production efficiency can be improved by reducing the enzyme activity in accordance with the reduction of the surface area of guanosine, and when the enzyme activity during the reaction was reduced, the production efficiency of 5′-guanylic acid was improved. The present invention has been completed and the present invention has been completed. That is, the present invention is as follows.

【0006】(1)グアノシンを酵素触媒下で重合リン
酸と反応させ、グアノシンをリン酸化して5’−グアニ
ル酸を生成させる、5’−グアニル酸の製造法におい
て、反応中に前記酵素の活性を低下させる処理を行うこ
とを特徴とする5’−グアニル酸の製造法である。 (2)前記酵素が酸性フォスファターゼである(1)の
5’−グアニル酸の製造法。 (3)前記酵素の活性を低下させる処理を、反応温度の
低下、酵素反応阻害剤の添加、気体バブリングから選ば
れる手段によって行うことを特徴とする(1)又は
(2)の5’−グアニル酸の製造法。
(1) In the method for producing 5'-guanylic acid, which comprises reacting guanosine with polymerized phosphoric acid under an enzyme catalyst to phosphorylate guanosine to produce 5'-guanylic acid, the reaction of the enzyme A method for producing 5'-guanylic acid, which comprises performing a treatment for reducing the activity. (2) The method for producing 5′-guanylic acid according to (1), wherein the enzyme is acid phosphatase. (3) The 5'-guanyl of (1) or (2), wherein the treatment for reducing the activity of the enzyme is performed by a means selected from reduction of reaction temperature, addition of an enzyme reaction inhibitor, and gas bubbling. Acid manufacturing method.

【0007】[0007]

【発明の実施の形態】以下、本発明を詳細に説明する。
本発明の5’−グアニル酸の製造法においては、グアノ
シンを酵素触媒下で重合リン酸と反応させ、グアノシン
をリン酸化して5’−グアニル酸を生成させる際に、反
応中に前記酵素の活性を低下させる処理を行う。
BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
In the method for producing 5′-guanylic acid of the present invention, when guanosine is reacted with polymerized phosphoric acid under an enzyme catalyst to phosphorylate guanosine to produce 5′-guanylic acid, the enzyme Perform processing to reduce activity.

【0008】本発明に用いる酵素としては、グアノシン
への、重合リン酸からのリン酸基の転移により5’−グ
アニル酸を生成する反応を触媒するものであれば制限は
ない。酵素の由来は特に制限されず、微生物、植物又は
動物等に由来する酵素を用いることができるが、微生物
に由来するものが好ましい。また、酵素は、微生物の野
生株又は変異株から調製したものであってもよく、遺伝
子工学的手法を用いて作製された形質転換株から調製し
たものであってもよい。さらに、酵素を産生する微生物
の菌体を含む培養物、該培養物から分離・回収した菌
体、該菌体を固定化処理、アセトン処理、凍結乾燥処理
等した菌体処理物を使用することもできる。
The enzyme used in the present invention is not limited as long as it catalyzes the reaction of producing 5'-guanylic acid by transfer of the phosphate group from the polymerized phosphate to guanosine. The origin of the enzyme is not particularly limited, and enzymes derived from microorganisms, plants or animals can be used, but those derived from microorganisms are preferable. In addition, the enzyme may be one prepared from a wild strain or mutant strain of the microorganism, or one prepared from a transformant strain prepared by using a genetic engineering technique. Further, use of a culture containing bacterial cells of an enzyme-producing microorganism, bacterial cells separated / collected from the culture, and treated bacterial cells obtained by subjecting the bacterial cells to an immobilization treatment, an acetone treatment, a freeze-drying treatment, or the like. You can also

【0009】本発明に用いる好ましい酵素として、酸性
フォスファターゼ(EC 3.1.3.2)が挙げられる。酸性ホ
スファターゼとしては、微生物に由来するものが好まし
く、特に好適な例として、モルガネラ属、エシェリヒア
属、プロビデンシア属、エンテロバクター属、クレブシ
エラ属又はセラチア属に属する細菌が、当該酵素活性を
有しており、これら細菌に由来する酵素がある。そのよ
うな細菌の代表例として以下のような菌株を挙げること
ができる。
Acid phosphatase (EC 3.1.3.2) is mentioned as a preferred enzyme used in the present invention. As the acid phosphatase, those derived from microorganisms are preferable, and as particularly preferable examples, bacteria belonging to the genera Morganella, Escherichia, Providencia, Enterobacter, Klebsiella or Serratia have the enzyme activity. , There are enzymes derived from these bacteria. Representative examples of such bacteria include the following strains.

【0010】モルガネラ・モルガニ(Morganella morg
anii) NCIMB 10466 モルガネラ・モルガニ(Morganella morganii) IFO 3
168 モルガネラ・モルガニ(Morganella morganii) IFO 3
848 エシェリヒア・ブラッタエ(Escherichia blattae) JC
M 1650 エシェリヒア・ブラッタエ(Escherichia blattae) AT
CC 33429 エシェリヒア・ブラッタエ(Escherichia blattae) AT
CC 33430 プロビデンシア・スチュアルティ(Providencia stuart
ii) ATCC 29851 プロビデンシア・スチュアルティ(Providencia stuart
ii) ATCC 33672 エンテロバクター・アエロゲネス(Enterobacter aerog
enes) IFO 12010 エンテロバクター・アエロゲネス(Enterobacter aerog
enes) IFO 13534 クレブシエラ・プランティコラ(Klebsiella planticol
a) IFO 14939 クレブシエラ・プランティコラ(Klebsiella planticol
a) IAM 1133 セラチア・フィカリア(Serratia ficaria) IAM 13540 セラチア・ マルセセンス(Serratia marcescens) IAM
12143 より好ましくは、ヌクレオシドに対する親和性が上昇し
た酸性フォスファターゼ(特開平10-201481参照)が挙
げられる。このような酸性フォスファターゼとして具体
的には、後記参考例1記載のエシェリヒア・ブラッタエ
由来変異型酸性フォスファターゼ、エンテロバクター・
アエロゲネス由来新規変異型酸性フォスファターゼ、及
び、特開平10-201481号公報記載の各種変異型酸性フォ
スファターゼが挙げられる。
Morganella morg
anii) NCIMB 10466 Morganella morganii IFO 3
168 Morganella morganii IFO 3
848 Escherichia blattae JC
M 1650 Escherichia blattae AT
CC 33429 Escherichia blattae AT
CC 33430 Providencia stuart
ii) ATCC 29851 Providencia stuart
ii) ATCC 33672 Enterobacter aeroges
enes) IFO 12010 Enterobacter aerog
enes) IFO 13534 Klebsiella planticol
a) IFO 14939 Klebsiella planticol
a) IAM 1133 Serratia ficaria IAM 13540 Serratia marcescens IAM
More preferred is 12143, and acid phosphatase with increased affinity for nucleosides (see JP-A-10-201481). Specific examples of such an acid phosphatase include Escherichia brattae-derived mutant acid phosphatase and Enterobacter described in Reference Example 1 described below.
Examples include novel mutant acid phosphatase derived from Aerogenes, and various mutant acid phosphatases described in JP-A-10-201481.

【0011】また、酸性フォスファターゼは、本来、リ
ン酸エステルを酸性条件下で加水分解する反応を触媒す
る酵素であり、リン酸転移反応により生成するヌクレオ
シド−5’−リン酸エステルを分解するヌクレオチダー
ゼ活性を有しているが、ヌクレオチダーゼ活性(リン酸
エステル加水分解活性)が低下した変異型酸性フォスフ
ァターゼ(WO96/37603参照)も、本発明に好適に使用す
ることができる。
Acid phosphatase is originally an enzyme that catalyzes a reaction of hydrolyzing a phosphate ester under acidic conditions, and a nucleotidase that decomposes a nucleoside-5'-phosphate ester produced by a phosphoryl transfer reaction. A mutant acid phosphatase (see WO96 / 37603) that has activity but has reduced nucleotidase activity (phosphate ester hydrolysis activity) can also be preferably used in the present invention.

【0012】さらに、温度安定性の向上した酸性フォス
ファターゼ、又は、ヌクレオシドに対する親和性が上昇
し、かつ、温度安定性の向上した酸性フォスファターゼ
(特開平10-201481)も、本発明に好適に用いることが
できる。
Further, acid phosphatase with improved temperature stability, or acid phosphatase with increased affinity for nucleoside and improved temperature stability (Japanese Patent Laid-Open No. 10-201481) is also preferably used in the present invention. You can

【0013】本発明において用いるグアノシンは特に制
限されないが、グアノシン結晶を物理的処理により粉砕
し、粉砕したグアノシン結晶を用いることが好ましい。
グアノシンの結晶の物理的処理による粉砕は、例えば、
グアノシンの結晶を水中でスラリーとし、一般的に用い
られている粉砕機(例えばスイスWAB社製DYNO-MILL等)
を用いて粉砕することによって行うことができる。この
ような処理によって、微細化された結晶のスラリーが得
られる。
The guanosine used in the present invention is not particularly limited, but it is preferable to use guanosine crystals obtained by pulverizing guanosine crystals by physical treatment and pulverizing.
Grinding of the crystals of guanosine by physical treatment is, for example,
A crusher commonly used as a slurry of guanosine crystals in water (for example, DYNO-MILL manufactured by WAB, Switzerland)
It can be carried out by pulverizing with. By such treatment, a slurry of finely divided crystals is obtained.

【0014】本発明においては、グアノシンの結晶を粉
砕することによって、5’−グアニル酸を生成する反応
の効率を高めることができる。したがって、前記反応効
率が向上する限り、粉砕の程度は特に問わないが、好ま
しくは、粉砕後の結晶の比表面積が0.4m2/g以
上、より好ましくは0.8m2/g以上となるように粉
砕することが望ましい。比表面積の上限は特に制限され
ないが、5’−グアニル酸の生成効率の向上は結晶の比
表面積が一定以上になると頭打ちになるので、通常は1
2/g程度で十分であると考えられる。しかし、グア
ノシンの結晶の粉砕は本発明に必須ではなく、5’−グ
アニル酸を生成する反応の効率が高まるという効果は、
反応中に酵素の活性を低下させる処理を行うことによっ
て得られる。
In the present invention, the efficiency of the reaction for producing 5'-guanylic acid can be increased by grinding the guanosine crystals. Therefore, the degree of pulverization is not particularly limited as long as the reaction efficiency is improved, but the specific surface area of the crystal after pulverization is preferably 0.4 m 2 / g or more, more preferably 0.8 m 2 / g or more. It is desirable to pulverize it. The upper limit of the specific surface area is not particularly limited, but the improvement in the production efficiency of 5'-guanylic acid reaches a ceiling when the specific surface area of the crystal becomes a certain value or more, and therefore it is usually 1
It is considered that about m 2 / g is sufficient. However, the crushing of guanosine crystals is not essential to the present invention, and the effect of increasing the efficiency of the reaction for producing 5'-guanylic acid is
It is obtained by performing a treatment for reducing the activity of the enzyme during the reaction.

【0015】粉砕によって微細化された結晶の平均粒径
は、例えば、stokesの抵抗則に基づく沈降法に従い、沈
降式粒度分布測定装置(例えば、島津製作所(株)遠心沈
降式粒度分布測定装置SA-CP3)を用いて測定することが
できる。また、こうして測定される平均粒径に基づい
て、微結晶の比表面積を計算することができる。
The average particle size of the crystal fined by pulverization is determined by, for example, a sedimentation type particle size distribution measuring device (for example, a centrifugal sedimentation type particle size distribution measuring device SA manufactured by Shimadzu Corporation) in accordance with a sedimentation method based on the Stokes resistance law. -CP3) can be used for measurement. Further, the specific surface area of the microcrystals can be calculated based on the average particle size thus measured.

【0016】粉砕するグアノシンの結晶は、精製された
ものであってもよく、グアノシンを産生する微生物の培
養液中に蓄積する結晶スラリーをそのまま用いてもよ
い。グアノシンは、例えば特公昭57−14160号公
報記載の方法によって取得することができる。また、メ
ルカプトグアノシンのような前駆体を用いることもでき
る。
The guanosine crystals to be crushed may be purified ones, or the crystal slurry accumulated in the culture solution of the guanosine-producing microorganism may be used as it is. Guanosine can be obtained, for example, by the method described in JP-B-57-14160. It is also possible to use a precursor such as mercaptoguanosine.

【0017】反応液に添加するグアノシンの濃度は1〜
20g/dlが望ましい。グアノシンの結晶を粉砕して微細化
することに加えて、硼酸あるいはジメチルスルホキシド
のような界面活性剤を反応液に添加すると、さらに反応
収率が向上する場合がある。
The concentration of guanosine added to the reaction solution is 1 to
20g / dl is desirable. In addition to pulverizing the guanosine crystals to make them finer, the addition of a surfactant such as boric acid or dimethylsulfoxide to the reaction solution may further improve the reaction yield.

【0018】また、本発明に用いる重合リン酸として
は、酵素反応によりグアノシンへリン酸基を転移して
5’−グアニル酸を生成し得るものであれば特に制限さ
れないが、具体的には、ピロリン酸、トリポリリン酸、
テトラポリリン酸、ペンタポリリン酸、もしくはこれら
の塩、又はこれらの任意の混合物が挙げられる。重合リ
ン酸の使用濃度は、リン酸受容体であるグアノシンの濃
度によって決定される。通常、グアノシンの1〜5倍量
が望ましい。
The polymerized phosphoric acid used in the present invention is not particularly limited as long as it can transfer a phosphoric acid group to guanosine by an enzymatic reaction to produce 5'-guanylic acid. Pyrophosphate, tripolyphosphate,
Examples include tetrapolyphosphoric acid, pentapolyphosphoric acid, or salts thereof, or any mixture thereof. The concentration of polymerized phosphate used is determined by the concentration of guanosine, which is a phosphate receptor. Usually, 1 to 5 times the amount of guanosine is desirable.

【0019】本発明においては、上記のような酵素を用
いてグアノシンに重合リン酸からリン酸基を転移させ、
グアノシンをリン酸化する反応において、反応中に酵素
活性を低下させる処理を行うことを特徴とする。反応中
に酵素活性を低下させる処理を行う以外は、グアノシン
を酵素的にリン酸化して5’−グアニル酸を生成せしめ
る通常の方法と同様にしてリン酸化反応を行うことがで
きる。
In the present invention, a phosphate group is transferred from polymerized phosphate to guanosine using the above-mentioned enzyme,
In the reaction of phosphorylating guanosine, it is characterized in that a treatment for reducing the enzyme activity is carried out during the reaction. The phosphorylation reaction can be carried out in the same manner as the usual method for enzymatically phosphorylating guanosine to produce 5′-guanylic acid, except that the treatment for reducing the enzyme activity is carried out during the reaction.

【0020】反応は通常、温度20〜60℃、好ましくは30
〜40℃で、pH3.0〜9.0、好ましくはpH3.5〜6.5、さらに
好ましくはpH3.5〜5.5の弱酸性側が好結果を与える。反
応には静置又は撹はんのいずれの方法も採用し得る。反
応時間は、使用する酵素の活性、基質濃度などの条件に
よって異なるが、1〜100時間である。
The reaction is usually carried out at a temperature of 20 to 60 ° C., preferably 30
At -40 ° C, pH 3.0-9.0, preferably pH 3.5-6.5, more preferably pH 3.5-5.5, the weakly acidic side gives good results. Either a static method or a stirring method can be adopted for the reaction. The reaction time varies depending on conditions such as the activity of the enzyme used and the substrate concentration, but is 1 to 100 hours.

【0021】酵素として酸性フォスファターゼを用いる
場合は、リン酸化反応をpH3.0から5.5の範囲の弱酸性に
調整することが好ましい。反応中の酵素活性を低下させ
る処理を行うことによって、グアノシンの生成速度を向
上させることができる。その結果、反応時間を減縮させ
ることができ、グアノシンの生成収率を高めることがで
きる。この理由は、次のように推定される。反応の初期
には、グアノシンから5’−グアニル酸が生成する反応
が進行するが、5’−グアニル酸の生成に伴って、基質
となるグアノシンの表面積が減少する一方、重合リン酸
が酵素により分解されるため、5’−グアニル酸の生成
効率が低下する。反応中に、グアノシンの表面積の低下
に合わせて酵素活性を低下させることによって、重合リ
ン酸の酵素による分解が抑えら、その結果5’−グアニ
ル酸の生成速度の減少が抑制される。酵素活性の低下
は、段階的に行ってもよく、連続的に行ってもよい。
When acid phosphatase is used as the enzyme, it is preferable to adjust the phosphorylation reaction to a weak acidity in the range of pH 3.0 to 5.5. By performing the treatment for reducing the enzyme activity during the reaction, the production rate of guanosine can be improved. As a result, the reaction time can be shortened and the production yield of guanosine can be increased. The reason for this is presumed as follows. In the initial stage of the reaction, the reaction of producing 5'-guanylic acid from guanosine proceeds, but the surface area of guanosine as a substrate decreases with the production of 5'-guanylic acid, while the polymerized phosphoric acid is produced by the enzyme. Since it is decomposed, the production efficiency of 5′-guanylic acid is reduced. During the reaction, the enzymatic activity is reduced in accordance with the decrease in the surface area of guanosine, so that the enzymatic decomposition of polymerized phosphoric acid is suppressed, and as a result, the decrease in the production rate of 5′-guanylic acid is suppressed. The enzyme activity may be reduced stepwise or continuously.

【0022】酵素活性の低下の程度、酵素活性を低下さ
せるタイミングは、用いる酵素の種類及び初発酵素活
性、グアノシンの比表面積、グアノシン及び重合リン酸
の濃度等によって、適宜設定することができる。具体的
には、酵素活性の低下の程度は、反応開始時の酵素活性
に対する活性低下処理後の酵素活性として、20〜80%、
より好ましくは20〜60%、さらに好ましくは30〜40%が
挙げられる。
The degree of reduction in enzyme activity and the timing of enzyme activity reduction can be appropriately set depending on the type of enzyme used, initial enzyme activity, specific surface area of guanosine, concentration of guanosine and polymerized phosphoric acid, and the like. Specifically, the degree of decrease in the enzyme activity is 20 to 80% as the enzyme activity after the activity decreasing treatment with respect to the enzyme activity at the start of the reaction.
More preferably, it is 20 to 60%, further preferably 30 to 40%.

【0023】酵素活性を低下させる方法としては、例え
ば、反応温度の低下、酵素反応阻害剤の添加、気
体バブリング、反応液のpHを至適反応pHから遠ざける
こと、等の手段が挙げられる。これらの手段を組み合わ
せることによって、酵素活性を低下させてもよい。これ
らの手段の中では、反応温度の低下、又は気体バブリン
グが、反応液中の5’−グアニル酸以外の成分を増加さ
せない点で好ましい。気体バブリングに用いる気体に特
に制限はなく、空気又は窒素ガス等を好適に用いること
ができる。
Examples of the method for lowering the enzyme activity include means such as lowering the reaction temperature, adding an enzyme reaction inhibitor, bubbling gas, and keeping the pH of the reaction solution away from the optimum reaction pH. The enzyme activity may be reduced by combining these means. Among these means, lowering the reaction temperature or gas bubbling is preferable in that it does not increase the components other than 5′-guanylic acid in the reaction solution. There is no particular limitation on the gas used for gas bubbling, and air, nitrogen gas, or the like can be preferably used.

【0024】尚、反応系に添加する酵素量を減らすこと
により、5’−グアニル酸の生成収率を上げることがで
きる場合がある(図2参照)。しかし、酵素量を減らす
と反応時間が遅延し、好ましくない場合もある。一方、
反応系に適当な量の酵素を加え、その後酵素活性を低下
させると、反応時間の遅延が抑制され、生成収率を向上
させることができる。
In some cases, the production yield of 5'-guanylic acid can be increased by reducing the amount of enzyme added to the reaction system (see FIG. 2). However, if the amount of enzyme is reduced, the reaction time may be delayed, which may not be preferable. on the other hand,
When an appropriate amount of enzyme is added to the reaction system and then the enzyme activity is reduced, the delay of reaction time is suppressed and the production yield can be improved.

【0025】上記のようにして生成した5’−グアニル
酸を反応終了混合物より採取分離するには、合成吸着樹
脂を用いる方法や沈殿剤を用いる方法、その他通常の採
取分離方法が採用できる。
In order to collect and separate the 5'-guanylic acid produced as described above from the reaction-terminated mixture, a method using a synthetic adsorption resin, a method using a precipitating agent, and other usual collecting and separating methods can be employed.

【0026】[0026]

【実施例】以下、本発明を実施例によりさらに具体的に
説明する。
EXAMPLES The present invention will be described in more detail below with reference to examples.

【0027】[0027]

【参考例1】エシェリヒア・ブラッタエ由来変異型酸性
フォスファターゼの取得 エシェリヒア・ブラッタエJCM1650由来野生型酸性フォ
スファターゼをコードする遺伝子を含むプラスミドpEPI
305(WO96/37603参照)を用い、このプラスミドDNAに遺
伝子工学的手法により部位特異的変異を導入し、変異型
酸性フォスファターゼをコードする遺伝子を作製した
(特開平10-201481参照)。
[Reference Example 1] Acquisition of mutant acid phosphatase derived from Escherichia blattae Plasmid pEPI containing a gene encoding wild-type acid phosphatase derived from Escherichia blattae JCM1650
Using 305 (see WO96 / 37603), a site-specific mutation was introduced into this plasmid DNA by a genetic engineering method to prepare a gene encoding a mutant acid phosphatase (see Japanese Patent Laid-Open No. 10-201481).

【0028】pEPI305はエシェリヒア・ブラッタエJCM16
50に由来する野生型酸性フォスファターゼをコードする
遺伝子を含む、制限酵素ClaIと制限酵素BamHIで切り出
される2.4Kbpの大きさのDNA断片を、ClaI及びBamHIで切
断したpBluescript KS(+)(ストラタジーン社製)に結
合したプラスミドDNAである。pEPI305をエシェリヒア・
コリ JM109に保持させた株は、AJ13144と命名され、平
成8年2月23日付で工業技術院生命工学工業技術研究所
(現 独立行政法人 産業技術総合研究所 特許生物寄託
センター、郵便番号305-5466 日本国茨城県つくば市東
1丁目1番地1中央第6)にブタペスト条約に基づき国
際寄託され、受託番号FERM BP-5423が付与されている。
PEPI305 is Escherichia blattae JCM16
A DNA fragment having a size of 2.4 Kbp, which is cleaved by restriction enzymes ClaI and BamHI, containing a gene encoding wild-type acid phosphatase derived from 50, and cleaved with ClaI and BamHI pBluescript KS (+) (Stratagene) Manufactured by the company). pEPI305 to Escherichia
The strain retained in Kori JM109 was named AJ13144, and was dated February 23, 1996, Institute of Biotechnology, Institute of Industrial Science and Technology (now National Institute of Advanced Industrial Science and Technology, Patent Biological Deposit Center, ZIP code 305- 5466 It has been internationally deposited under the Budapest Treaty at 1-chome, 1-chome, 1-chome, 1-chome, Tsukuba, Ibaraki, Japan, and has been given the deposit number FERM BP-5423.

【0029】DNA合成装置(アプライドバイオシステム
社製モデル394)を用いてホスホアミダイト法にて配列
番号1及び配列番号2に示すオリゴヌクレオチドMUT300
及びMUT370をそれぞれ合成した。
Oligonucleotide MUT300 shown in SEQ ID NO: 1 and SEQ ID NO: 2 by the phosphoramidite method using a DNA synthesizer (Model 394 manufactured by Applied Biosystems)
And MUT370 were synthesized respectively.

【0030】鋳型としてpEPI305 1ng、プライマーとし
てM13プライマーRV(宝酒造社製)およびMUT370オリゴ
ヌクレオチド各2.5μmolおよびタックDNAポリメラーゼ
(宝酒造社製)2.5ユニットをdATP、dCTP、dGTP、dTTP
各200μM、塩化カリウム50mMおよび塩化マグネシウム
1.5mMを含む100mM トリス−塩酸緩衝液(pH8.3)100μl
に添加し、94℃を30秒、55℃を2分、72℃を3分のサイク
ルを25回繰り返すPCR反応を行った。PCR反応はサ
ーマルサイクラーPJ2000型(宝酒造社製)を用いて行っ
た。また別に、鋳型としてプラスミドDNA pEPI305 1n
g、プライマーとしてM13プライマーM3(宝酒造社製)お
よびMUT300オリゴヌクレオチド各2.5μmolを用いて同様
にPCR反応を行った。それぞれの反応液をマイクロス
ピンカラムS-400(ファルマシア社製)を用いてゲル濾
過により精製し、プライマーを除去した。
PEPI305 1 ng as a template, M13 primer RV (manufactured by Takara Shuzo) and 2.5 μmol of MUT370 oligonucleotide each as a primer and 2.5 units of tack DNA polymerase (manufactured by Takara Shuzo) were dATP, dCTP, dGTP and dTTP.
200 μM each, potassium chloride 50 mM and magnesium chloride
100 mM Tris-HCl buffer (pH 8.3) containing 1.5 mM 100 μl
Then, a PCR reaction was carried out in which the cycle of 94 ° C. for 30 seconds, 55 ° C. for 2 minutes, and 72 ° C. for 3 minutes was repeated 25 times. The PCR reaction was performed using a thermal cycler PJ2000 type (manufactured by Takara Shuzo). Separately, plasmid DNA pEPI305 1n was used as a template.
Similarly, PCR was performed using M13 primer M3 (manufactured by Takara Shuzo Co., Ltd.) and 2.5 μmol of MUT300 oligonucleotide as primers. Each reaction solution was purified by gel filtration using Micro Spin Column S-400 (Pharmacia) to remove the primer.

【0031】それぞれのPCR反応液1μlをdATP、dCT
P、dGTP、dTTP各200μM、塩化カリウム 50mMおよび塩化
マグネシウム 1.5mMを含む100mM トリス−塩酸緩衝液
(pH8.3)95μlに添加し、94℃で10分加熱後、60分間か
けて37℃まで冷却した後、37℃で15分保温しヘテロ二本
鎖を形成させた。これにタックDNAポリメラーゼ2.5ユニ
ットを添加して72℃で3分反応を行い、ヘテロ二本鎖を
完成させた。次に、この反応液にM13プライマーRVおよ
びM13プライマーM3各2.5μmolを添加して、94℃を30
秒、55℃を2分、72℃を3分のサイクルを10回繰り返すP
CR反応を行った。
1 μl of each PCR reaction solution was dATP, dCT
Add 95 μl of 100 mM Tris-HCl buffer (pH 8.3) containing P, dGTP, dTTP 200 μM each, potassium chloride 50 mM and magnesium chloride 1.5 mM, heat at 94 ° C. for 10 minutes, then cool to 37 ° C. over 60 minutes. After that, the mixture was incubated at 37 ° C for 15 minutes to form a heteroduplex. To this, 2.5 units of Tack DNA Polymerase was added and reacted at 72 ° C for 3 minutes to complete the heteroduplex. Next, add 2.5 μmol of each of M13 primer RV and M13 primer M3 to this reaction mixture,
Seconds, 55 ℃ 2 minutes, 72 ℃ 3 minutes cycle 10 times P
A CR reaction was performed.

【0032】2回目のPCR反応の生成物をClaIとBamHI
で切断後フェノール/クロロホルム抽出し、エタノール
沈殿した。このDNA断片をClaIとBamHIで切断したpBlues
cript KS(+)に結合し、得られたプラスミドDNAを用いて
常法によりエシェリヒア・コリJM109(宝酒造製)を形
質転換した。これを100μg/mlのアンピシリンを含むL
寒天培地上にプレーティングし、形質転換体を得た。
形質転換体よりアルカリ溶菌法によりプラスミドを調製
し、塩基配列の決定を行い、目的の塩基が置換されてい
ることを確認した。塩基配列の決定は Taq DyeDeoxy Te
rminator Cycle Sequencing Kit (アプライドバイオケ
ミカル社製)を用い、サンガーらの方法(J. Mol. Bio
l., 143, 161(1980))に従って行った。
The product of the second PCR reaction was digested with ClaI and BamHI.
After cutting with, the mixture was extracted with phenol / chloroform and precipitated with ethanol. PBlues obtained by cutting this DNA fragment with ClaI and BamHI
Escherichia coli JM109 (Takara Shuzo Co., Ltd.) was transformed with the obtained plasmid DNA by binding to cript KS (+) by a conventional method. L containing 100 μg / ml ampicillin
A transformant was obtained by plating on an agar medium.
A plasmid was prepared from the transformant by the alkaline lysis method, the base sequence was determined, and it was confirmed that the target base was replaced. The nucleotide sequence can be determined by Taq DyeDeoxy Te
Using the rminator Cycle Sequencing Kit (manufactured by Applied Biochemicals), the method of Sanger et al. (J. Mol. Bio
l., 143, 161 (1980)).

【0033】このようにして、成熟蛋白質の63番目の
ロイシン残基(CTG)がグルタミン残基(C*AG)に、6
5番目のアラニン残基(GCG)がグルタミン残基(*C*A
G)に、66番目のグルタミン酸残基(GAA)がアラニン
残基(G*CA)に、69番目のアスパラギン残基(AAC)
がアスパラギン酸残基(*GAC)に、71番目のセリン残
基(AGC)がアラニン残基(*G*CC)に、72番目のセリ
ン残基(AGT)がアラニン残基(*G*CT)に、74番目の
グリシン残基(GGG)がアスパラギン酸残基( *G*A*T)
に、135番目のスレオニン残基(ACC)がリジン残基
*A*A*A)に、136番目のグルタミン酸残基(GAG)
がアスパラギン酸残基(GA*C)に、153番目のイソロ
イシン残基(ATC)がスレオニン残基(A*CC)にそれぞ
れ置換した、変異型フォスファターゼをコードする変異
型遺伝子を作製した。この変異型遺伝子を含むプラスミ
ドをpEPI370と命名した。
Thus, the 63rd position of the mature protein
Leucine residue (CTG) is replaced with glutamine residue (C*AG), 6
The fifth alanine residue (GCG) is the glutamine residue (*C*A
G), the 66th glutamic acid residue (GAA) is alanine
Residue (G*CA) to the 69th asparagine residue (AAC)
Is an aspartic acid residue (*GAC), the 71st serine left
The group (AGC) is an alanine residue (*G*CC), the 72nd auction
Residue (AGT) is an alanine residue (*G*CT), the 74th
Glycine residue (GGG) is an aspartic acid residue ( *G*A*T)
And the 135th threonine residue (ACC) is a lysine residue
(*A*A*A), the 136th glutamic acid residue (GAG)
Is an aspartic acid residue (GA*C), the 153rd isoro
Isine residue (ATC) is threonine residue (A*CC)
Mutation that encodes the mutated phosphatase
A type gene was created. A plasmid containing this mutant gene
This is named pEPI370.

【0034】上記プラスミドpEPI370を保持するエシェ
リヒア・コリJM109/pEPI370をL培地50mlに接種し、37
℃で16時間培養後、培養液から遠心分離により集菌し、
酸性フォスファターゼを含む菌体を取得した。
Escherichia coli JM109 / pEPI370 harboring the above plasmid pEPI370 was inoculated into 50 ml of L medium to give 37
After culturing for 16 hours at ℃, collect from the culture solution by centrifugation,
Bacteria containing acid phosphatase were obtained.

【0035】[0035]

【参考例2】グアノシン結晶の粉砕 グアノシン結晶を水中でスラリーとし、粉砕機(スイス
WAB社製DYNO-MILL)により結晶の粉砕処理を行った。こ
の際、粉砕時間などの条件を変更して様々な粒経の結晶
を取得した。グアノシン結晶は単位重量あたりの比表面
積は0.2m2/gであったものが、粉砕後0.4〜0.8m2/g以上
に増加し、結晶の微細化が可能であった。なお、グアノ
シン結晶の比表面積はstokesの抵抗則に基づく沈降法に
従い、沈降式粒度分布測定装置(島津製作所(株)遠心沈
降式粒度分布測定装置SA-CP3)で測
[Reference Example 2] Grinding guanosine crystals A guanosine crystal was slurried in water and a crusher (Swiss
The crystals were pulverized by WAB DYNO-MILL). At this time, conditions such as crushing time were changed to obtain crystals with various grain sizes. The specific surface area per unit weight of guanosine crystals was 0.2 m 2 / g, but after pulverization, it increased to 0.4 to 0.8 m 2 / g or more, and the crystals could be refined. Note that the specific surface area of guanosine crystals was measured by a sedimentation-type particle size distribution analyzer (Shimadzu Corporation centrifugal sedimentation-type particle size distribution analyzer SA-CP3) according to the sedimentation method based on the Stokes resistance law.

【参考例3】温度変化による酵素活性の変化 参考例2と同様にして粉砕したグアノシン粉砕結晶(比
表面積0.8m2/g)0.5g/dl、酸性ピロリン酸100mM、酢酸1
00mMを含む溶液(苛性ソーダにてpH5.0に調整)1mlを、
恒温槽にて各種温度(25〜50℃)で10分間、加温した。
これらの溶液に、参考例1で得た酸性フォスファターゼ
を含む菌体(100mg/dl)を100μl添加し、各温度で5分
間反応させた。その後、2N 塩酸200μlを添加し、反応
を停止させた。各反応液中の5’−グアニル酸の量を測
定した。その結果、反応温度を上げるに従い、5’−グ
アニル酸の生成量が上昇し(図1)、酸性フォスファタ
ーゼの比活性が上昇することが示された。
[Reference Example 3] Change in enzyme activity due to temperature change Guanosine ground crystals (specific surface area 0.8 m 2 / g) 0.5 g / dl ground in the same manner as in Reference Example 2, acidic pyrophosphate 100 mM, acetic acid 1
1 ml of a solution containing 00 mM (adjusted to pH 5.0 with caustic soda)
It was heated in a constant temperature bath at various temperatures (25 to 50 ° C) for 10 minutes.
To these solutions, 100 μl of the bacterial cells (100 mg / dl) containing the acid phosphatase obtained in Reference Example 1 was added and reacted at each temperature for 5 minutes. Then, 200 μl of 2N hydrochloric acid was added to stop the reaction. The amount of 5'-guanylic acid in each reaction solution was measured. As a result, it was shown that as the reaction temperature was increased, the amount of 5′-guanylic acid produced increased (FIG. 1) and the specific activity of acid phosphatase increased.

【0036】[0036]

【実施例1】 5’−グアニル酸の製造(I)(反応温
度低下による酸性フォスファターゼ活性の低下) 酸性ピロリン酸29.3g、グアノシンの粉砕結晶(比表面
積0.6m2/g)のスラリー12.5g(グアノシン含量として)
を水溶液中で混合して苛性ソーダでpH4.5付近に調整
後、前記菌体を400mg又は300mg添加して最終液量が100m
lになるように調整し、表1に示す反応温度で14時間反
応を行い、0.5時間毎に生成した5’−グアニル酸の量
を測定した。反応は水浴中で行い、反応温度のコントロ
ールは水浴の温度をコントロールすることにより行い、
反応温度は直接反応液の温度を測定することにより確認
した。表中、「→」は反応温度の変化を表し、温度変更
時間は反応開始から反応温度をシフトさせるまでの時間
を表す。
Example 1 Production of 5′-guanylic acid (I) (reduction of acid phosphatase activity by lowering reaction temperature) 29.3 g of acidic pyrophosphate, 12.5 g of slurry of pulverized guanosine crystals (specific surface area 0.6 m 2 / g) ( As guanosine content)
Was mixed in an aqueous solution and adjusted to around pH 4.5 with caustic soda, and the final volume was 100 m by adding 400 mg or 300 mg of the cells.
The amount of 5'-guanylic acid produced was measured every 0.5 hours by adjusting the reaction time to 1 and reacting for 14 hours at the reaction temperature shown in Table 1. The reaction is carried out in a water bath, the reaction temperature is controlled by controlling the temperature of the water bath,
The reaction temperature was confirmed by directly measuring the temperature of the reaction solution. In the table, “→” represents a change in the reaction temperature, and the temperature change time represents a time from the start of the reaction to the shift of the reaction temperature.

【0037】反応条件(酵素量、反応温度、温度変更時
間)と、5’−グアニル酸最大蓄積時点での反応時間、
蓄積、収率を表1に、経時的な収率変化を図2に示し
た。その結果、反応途中で温度を低下させた条件(実験
区1-2、1-3)では、反応温度一定の条件(実験区1-1)
に比較して、最大蓄積時点までの反応時間の遅延が少な
く、5’−グアニル酸生成収率で2〜3%、対リン酸収
率で0.3〜0.5%、生成効率が向上した。
Reaction conditions (enzyme amount, reaction temperature, temperature change time) and reaction time at the time of maximum accumulation of 5'-guanylic acid,
The accumulation and yield are shown in Table 1, and the change in yield over time is shown in FIG. As a result, under the conditions where the temperature was lowered during the reaction (Experimental Zones 1-2 and 1-3), the reaction temperature was constant (Experimental Zone 1-1).
Compared with the above, the reaction time to the maximum accumulation time was less delayed, the yield of 5'-guanylic acid was 2-3%, the yield of phosphoric acid was 0.3-0.5%, and the production efficiency was improved.

【0038】[0038]

【表1】 [Table 1]

【0039】[0039]

【実施例2】 5’−グアニル酸の製造(II)(反応温
度低下による酸性フォスファターゼ活性の低下) 酸性ピロリン酸29.3g、及びグアノシン結晶の7.5g(グ
アノシン含量として)を水溶液中で混合して苛性ソーダ
でpH4.5付近に調整後、上記菌体を100〜1500mg添加して
最終液量が100mlになるように調整し、表2に示す反応
温度で30時間反応を行い、適宜サンプリングし、生成し
た5’−グアニル酸の量を測定した。反応は水浴中で行
った。反応温度の測定及びコントロールは、実施例1と
同様にして行った。
Example 2 Production of 5′-guanylic acid (II) (reduction of acid phosphatase activity by lowering reaction temperature) 29.3 g of acid pyrophosphate and 7.5 g (as guanosine content) of guanosine crystals were mixed in an aqueous solution. After adjusting the pH to around 4.5 with caustic soda, 100 to 1500 mg of the above-mentioned bacterial cells was added to adjust the final liquid volume to 100 ml, and the reaction was carried out at the reaction temperature shown in Table 2 for 30 hours, and sampling was performed as appropriate. The amount of 5'-guanylic acid was measured. The reaction was carried out in a water bath. The reaction temperature was measured and controlled in the same manner as in Example 1.

【0040】反応条件(酵素量、反応温度、温度変更時
間)と、5’−グアニル酸最大蓄積時点での反応時間、
蓄積、収率を表2及び図3に示した。その結果、温度変
更を実施した実験区では、温度変更を実施しない実験区
に比べて、反応時間の増加が少なく、生成収率の向上が
認められた。
Reaction conditions (enzyme amount, reaction temperature, temperature change time) and reaction time at the time of maximum accumulation of 5'-guanylic acid,
The accumulation and yield are shown in Table 2 and FIG. As a result, in the experimental group where the temperature was changed, the reaction time was less increased and the production yield was improved compared to the experimental group where the temperature was not changed.

【0041】[0041]

【表2】 [Table 2]

【0042】[0042]

【実施例3】 5’−グアニル酸の製造(III)(バブリ
ングによる酸性フォスファターゼ活性の低下) 酸性ピロリン酸29.3g、及びグアノシン結晶の7.5g(グ
アノシン含量として)を水溶液中で混合して苛性ソーダ
でpH4.5付近に調整後、上記菌体を100〜1500mg添加して
最終液量が100mlになるように調整し、反応温度35℃で3
0時間反応を行った。反応中、反応液はマグネチックス
ターラーにて攪拌した。実験区5,6,7に関しては、
表3に示した通り反応中に1hr、空気をバブリング(口
径2mmのチューブから100ml/分)し、酵素を一部失活
させた。適宜サンプリングし、生成した5’−グアニル
酸の量を測定した。表3中、「〜」はバブリングを実施
した時間帯を表し、例えば「6〜7」は、反応開始後6
時間〜7時間の間にバブリングを行ったことを表す。
Example 3 Production of 5′-guanylic acid (III) (reduction of acid phosphatase activity by bubbling) 29.3 g of acid pyrophosphate and 7.5 g (as guanosine content) of guanosine crystals were mixed in an aqueous solution, and caustic soda was added. After adjusting the pH to around 4.5, add 100 to 1500 mg of the above-mentioned cells to adjust the final liquid volume to 100 ml, and react at a reaction temperature of 35 ° C for 3
Reaction was carried out for 0 hours. During the reaction, the reaction solution was stirred with a magnetic stirrer. Regarding Experiment Zones 5, 6 and 7,
As shown in Table 3, air was bubbled (100 ml / min from a tube having a diameter of 2 mm) for 1 hr during the reaction to partially inactivate the enzyme. The sample was appropriately sampled, and the amount of 5'-guanylic acid produced was measured. In Table 3, "~" represents the time period when the bubbling was carried out, and for example, "6-7" was 6 after the start of the reaction.
It indicates that bubbling was performed during the time from 7 hours.

【0043】反応条件(酵素量、反応温度、バブリング
時間)と、最大蓄積時点での反応時間、蓄積、収率を表
3及び図4に示した。その結果、バブリングにより酵素
失活を実施した実験区では、酵素失活を実施しない実験
区に比べ、反応時間の増加が少なく、生成収率の向上が
認められた。
Table 3 and FIG. 4 show the reaction conditions (enzyme amount, reaction temperature, bubbling time) and the reaction time at the maximum accumulation time, accumulation and yield. As a result, in the experimental section in which the enzyme was inactivated by bubbling, the reaction time was less increased and the production yield was improved compared with the experimental section in which the enzyme was not inactivated.

【0044】[0044]

【表3】 [Table 3]

【0045】[0045]

【参考例4】実施例3の実験区1と同様の組成の反応液
を2反応分、作製し、35℃で反応させた。それらの一方
については、反応開始時から空気をバブリング(口径2m
mのチューブから100ml/分)した。反応液を適宜サンプ
リングし、下記に示す方法で反応液中の酵素活性を測定
した。
[Reference Example 4] Two reaction solutions each having the same composition as in Experiment Group 1 of Example 3 were prepared and reacted at 35 ° C. For one of them, bubbling air from the beginning of the reaction (caliber 2m
(100 ml / min from the m tube). The reaction solution was appropriately sampled, and the enzyme activity in the reaction solution was measured by the method described below.

【0046】100mM MES、5mM PNPP(p-nitrophenyl pho
sphate)を含む測定液(苛性ソーダにてpH6.0に調整)1
mlを、恒温槽にて30℃で10分間、加温した。この測定液
に、前記のリン酸化反応液サンプルの10倍希釈液を80μ
l添加し、30℃で1分間、反応させた後、10N 苛性ソー
ダ80μl添加し、反応を停止した。各サンプルの410nmの
吸光度を測定し、以下の式に従ってリン酸化反応中の酵
素活性の経時変化を算出した。
100 mM MES, 5 mM PNPP (p-nitrophenyl pho
Measurement solution containing sphate (adjusted to pH 6.0 with caustic soda) 1
ml was heated in a constant temperature bath at 30 ° C. for 10 minutes. Add 80 μl of the 10-fold diluted solution of the phosphorylation reaction solution sample described above to this measurement solution.
After adding 1 l and reacting at 30 ° C. for 1 minute, 80 μl of 10N caustic soda was added to stop the reaction. The absorbance at 410 nm of each sample was measured, and the change with time of the enzyme activity during the phosphorylation reaction was calculated according to the following formula.

【0047】その結果、図5に示す通り、バブリングを
行うことにより、酵素活性が低下した。空気の代わりに
窒素ガスをバブリングした場合も、同様に酵素活性が低
下した。
As a result, as shown in FIG. 5, the enzyme activity was lowered by bubbling. Similarly, when bubbling nitrogen gas instead of air, the enzyme activity also decreased.

【0048】[0048]

【数1】各反応時間における相対酵素活性=(反応時間
経過後の酵素活性)/(反応開始時の酵素活性)
[Equation 1] Relative enzyme activity at each reaction time = (enzyme activity after reaction time) / (enzyme activity at the start of reaction)

【数2】反応開始時の酵素活性=(反応開始時の吸光
度)−(ブランクの吸光度) ブランク:反応液の代わりに水を加えたもの)の吸光度
[Equation 2] Enzyme activity at the start of reaction = (absorbance at the start of reaction)-(absorbance of blank) Blank: Absorbance of water added in place of reaction solution)

【数3】反応時間経過後の酵素活性=(反応時間経過後
の酵素活性)−(ブランクの吸光度)
[Equation 3] Enzyme activity after reaction time = (Enzyme activity after reaction time)-(Blank absorbance)

【0049】[0049]

【発明の効果】本発明により、難溶性のグアノシン、及
び重合リン酸を用いて、酵素反応により効率よく5’−
グアニル酸を製造することができる。
INDUSTRIAL APPLICABILITY According to the present invention, a poorly soluble guanosine and polymerized phosphoric acid are used to efficiently perform 5'- reaction by an enzymatic reaction.
Guanilic acid can be produced.

【0050】[0050]

【配列表】 SEQUENCE LISTING <110> 味の素株式会社(Ajinomoto Co., Inc.) <120> 5’−グアニル酸の製造法(Method for Producing 5'-Ganylic Acid) <130> P-8855 <140> <141> 2001-07-10 <160> 2 <170> PatentIn Ver. 2.0 <210> 1 <211> 20 <212> DNA <213> Artificial Sequence <220> <223> Description of Artificial Sequence: primer for PCR <400> 1 cctcgaggtc gacggtatcg 20 <210> 2 <211> 21 <212> DNA <213> Artificial Sequence <220> <223> Description of Artificial Sequence: primer for PCR <400> 2 gcatatagtg ttctttcgcg c 21[Sequence list]                                SEQUENCE LISTING <110> Ajinomoto Co., Inc. <120> Method for Producing 5'-Ganylic Acid <130> P-8855 <140> <141> 2001-07-10 <160> 2 <170> PatentIn Ver. 2.0 <210> 1 <211> 20 <212> DNA <213> Artificial Sequence <220> <223> Description of Artificial Sequence: primer for PCR <400> 1 cctcgaggtc gacggtatcg 20 <210> 2 <211> 21 <212> DNA <213> Artificial Sequence <220> <223> Description of Artificial Sequence: primer for PCR <400> 2 gcatatagtg ttctttcgcg c 21

【図面の簡単な説明】[Brief description of drawings]

【図1】 グアノシンと酸性ピロリン酸から酸性フォス
ファターゼによる反応によって5’−グアニル酸を生成
させる反応において、反応温度と5’−グアニル酸の生
成量との関係を示す図。
FIG. 1 is a diagram showing the relationship between the reaction temperature and the amount of 5′-guanylic acid produced in a reaction in which guanosine and acidic pyrophosphate are reacted with acid phosphatase to produce 5′-guanylic acid.

【図2】 5’−グアニル酸収率の経時的変化を示す
図。
FIG. 2 is a graph showing changes with time in 5′-guanylic acid yield.

【図3】 5’−グアニル酸収率の経時的変化を示す
図。
FIG. 3 is a graph showing changes in 5′-guanylic acid yield over time.

【図4】 5’−グアニル酸収率の経時的変化を示す
図。
FIG. 4 is a graph showing changes over time in 5′-guanylic acid yield.

【図5】 反応液のバブリング実施下、不実施下におけ
る、反応液中の酵素活性の経時的変化を示す図。
FIG. 5 is a diagram showing changes over time in enzyme activity in a reaction solution with and without bubbling of the reaction solution.

フロントページの続き (72)発明者 飯田 巌 神奈川県川崎市川崎区鈴木町1−1味の素 株式会社国際生産推進センター内 Fターム(参考) 4B024 AA01 AA05 BA11 EA04 HA03 4B064 AF23 CA21 CB27 CC06 CC12 DA01 DA10 Continued front page    (72) Iwa Iwa, the inventor             Ajinomoto 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa             International Production Promotion Center Co., Ltd. F-term (reference) 4B024 AA01 AA05 BA11 EA04 HA03                 4B064 AF23 CA21 CB27 CC06 CC12                       DA01 DA10

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 グアノシンを酵素触媒下で重合リン酸と
反応させ、グアノシンをリン酸化して5’−グアニル酸
を生成させる、5’−グアニル酸の製造法において、反
応中に前記酵素の活性を低下させる処理を行うことを特
徴とする5’−グアニル酸の製造法。
1. A method for producing 5'-guanylic acid, which comprises reacting guanosine with polymerized phosphoric acid under an enzyme catalyst to phosphorylate guanosine to produce 5'-guanylic acid, wherein the activity of the enzyme is increased during the reaction. The method for producing 5′-guanylic acid is characterized by carrying out a treatment for decreasing
【請求項2】 前記酵素が酸性フォスファターゼである
請求項1に記載の5’−グアニル酸の製造法。
2. The method for producing 5′-guanylic acid according to claim 1, wherein the enzyme is acid phosphatase.
【請求項3】 前記酵素の活性を低下させる処理を、反
応温度の低下、酵素反応阻害剤の添加、気体バブリング
から選ばれる手段によって行うことを特徴とする請求項
1又は2に記載の5’−グアニル酸の製造法。
3. The 5 ′ according to claim 1 or 2, wherein the treatment for reducing the activity of the enzyme is performed by a means selected from reduction of reaction temperature, addition of an enzyme reaction inhibitor, and gas bubbling. -A method for producing guanylic acid.
JP2001209468A 2001-07-10 2001-07-10 Process for producing 5'-guanylic acid Expired - Fee Related JP4649787B2 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100721868B1 (en) 2006-07-20 2007-05-28 케이엔디티앤아이 주식회사 THE SYSTEM OF OPERATION ON CRYSTALLIZATION USING Couette-Taylor REACTORS OVER GMP

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996037603A1 (en) * 1995-05-25 1996-11-28 Ajinomoto Co., Inc. Process for producing nucleoside-5'-phosphate
JPH10201481A (en) * 1996-11-21 1998-08-04 Ajinomoto Co Inc Production of nucleoside 5'-phosphate

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996037603A1 (en) * 1995-05-25 1996-11-28 Ajinomoto Co., Inc. Process for producing nucleoside-5'-phosphate
JPH10201481A (en) * 1996-11-21 1998-08-04 Ajinomoto Co Inc Production of nucleoside 5'-phosphate

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100721868B1 (en) 2006-07-20 2007-05-28 케이엔디티앤아이 주식회사 THE SYSTEM OF OPERATION ON CRYSTALLIZATION USING Couette-Taylor REACTORS OVER GMP

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