𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Acetohydroxyacid synthase from Claviceps purpurea: Partial purification and characterization

✍ Scribed by Dr. Walter Maier; Rajesh Luthra; Detlef Gröger

Publisher
John Wiley and Sons
Year
1989
Tongue
English
Weight
466 KB
Volume
29
Category
Article
ISSN
0233-111X

No coin nor oath required. For personal study only.

✦ Synopsis

An acetohydroxyacid synthase (EC 4.1.3.18) which synthesizes a-acetolactate from pyruvate has been isolated from two different CIaviceps purpurea strains. A purification of about 142-fold was achieved by ammonium sulfate fractionation and the use of Sepharose 6B and DEAE-Sepharose CL-6B columns. The purified enzyme requires thiamine pyrophosphate and a divalent metal ion (Mn2+ or Mg2 ') for maximum activity but no FAD. The optimum pH is about 6.0 and the optimum temperature is 40 "C. The enzyme is not inhibited by branched-chain amino acids neither singly nor in combination. AHAS is strongly inhibited by p-chloromercuribenzoate and N-ethylmaleimide. The apparent K , values for pyruvate and TPP are 1.7 x lo-' M and 1.2 x lo-' M, respectively.

📜 SIMILAR VOLUMES

Purification and partial characterizatio
Purification and partial characterization of external and internal invertases from two strains of trichosporon adeninovorans
✍ R. Büttner; U. Schubert; R. Bode; D. Birnbaum 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 435 KB

We investigated the extracellular and intracellular invertase activity of two Trichosporon adeninovorans strains. Both strains (SBUG 724 and CBS 2844) secrete one invertase into the medium. The external enzymes were purified by chromatography on hydroxylapatite. The molecular weight of the external

Ethanolic extraction, purification, and
Ethanolic extraction, purification, and partial characterization of a fluorescent toxin from the coral reef crab, Lophozozymus pictor
✍ C. O. Lau; C. H. Tan; H. E. Khoo; Q. T. Li; R. Yuen 📂 Article 📅 1995 🏛 John Wiley and Sons 🌐 English ⚖ 359 KB

A purification procedure for Lophozozymus pictortoxin (IPTX) following ethanolic extraction of whole crab homogenate is described. The ethanol-extracted toxin (LPTX-E) had higher yield and specific activity than the hot aqueous-extracted one (LPTX-H). It was found that LPTX-E was fluorescent and coc