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Industrial Biotransformations

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Aspartase<br />

Escherichia coli<br />

1 = fumaric acid<br />

2 = aspartic acid<br />

Fig. 4.3.1.1 – 1<br />

1) Reaction conditions<br />

[1]: 2 M, 232.14 g · L –1 [116.07 g · mol –1 ]<br />

T: 37 °C<br />

medium: aqueous<br />

reaction type: C-N bond cleavage<br />

catalyst: immobilized enzyme<br />

enzyme: l-aspartate ammonia-lyase (fumaric aminase, aspartase)<br />

strain: Escherichia coli<br />

CAS (enzyme): [9027–30–9]<br />

2) Remarks<br />

● 4MNH4OH is added as the amine source.<br />

● Isolated enzyme is immobilized on Duolite A-7, a weakly basic anion-exchange resin.<br />

● The column reactor is operated for over 3 months at over 99 % conversion.<br />

● For the same syntheses, Tanabe Seiyaku has used an immobilized whole cell system since<br />

1973 (see page 500), instead of suspended whole cells used by Mitsubishi Petrochemical Co.<br />

Ltd. (see page 498). Biocatalytics, Inc. uses an immobilized enzyme (see page 494).<br />

3) Flow scheme<br />

Not published.<br />

4) Process parameters<br />

conversion: > 99 %<br />

ee: > 99.9 %<br />

reactor type: plug flow reactor<br />

residence time: 0.75 h<br />

enzyme consumption:<br />

start-up date:<br />

t½ =18d<br />

1974<br />

company: Kyowa Hakko Kogyo Co, Ltd., Japan<br />

496<br />

HOOC<br />

COOH<br />

E<br />

+ NH3<br />

HOOC<br />

NH2<br />

1 L-2<br />

COOH<br />

EC 4.3.1.1<br />

Kyowa Hakko Kogyo Co, Ltd.

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