The tryptophanase-tryptophan reaction; the nature of the enzyme-coenzyme-substrate complex.
نویسندگان
چکیده
منابع مشابه
The tryptophanase-tryptophan reaction. 9. The nature, characteristics and partial purification of the tryptophanase complex.
The name tryptophanase was given by Happold & Hoyle (1935) to the enzyme complex of Escherichia coli which induces and catalyzes the production of indole from tryptophan by non-viable bacterial preparations with the consumption of five atoms of oxygen (Woods, 1935). The present communication describes the preparation of this complex in the cell-free state, and subsequent investigation of the co...
متن کاملThe relation of spectral changes and tritium exchange reactions to the mechanism of tryptophanase-catalyzed reactions.
Holotryptophanase in the presence of K+ undergoes a pHdependent change (pK 7.2) from a protonated, enzymatically inactive form (EH), X,,, 420 rnp, to a deprotonated, active form (S), X,,, 337 mp. Only the inactive form appears when K+, which is required for activity, is replaced by Na+ or imidazole. Both forms of the enzyme are completely inactivated by borohydride reduction, indicating that ea...
متن کاملReversibility of the tryptophanase reaction: synthesis of tryptophan from indole, pyruvate, and ammonia.
Degradation of tryptophan to indole, pyruvate, and ammonia by tryptophanase (EC 4....) from Escherichia coli, previously thought to be an irreversible reaction, is readily reversible at high concentrations of pyruvate and ammonia. Tryptophan and certain of its analogues, e.g., 5-hydroxytryptophan, can be synthesized by this reaction from pyruvate, ammonia, and indole or an appropriate derivativ...
متن کاملThe degradation of some Bz-substituted tryptophans by Escherichia coli tryptophanase.
The present paper is the second in a series designed to correlate substrate structure with the kinetic constants of enzyme-catalysed reactions and thus throw light on the nature of the attachment of the substrate to the enzyme. Since the preparation of the first paper (Nath & Rydon, 1954), which describes the influence of structure on the hydrolysis of substituted phenylf-D-glucosides by emulsi...
متن کاملReaction pathway of tryptophanase-catalyzed L-tryptophan synthesis from D-serine.
Tryptophanase, L-tryptophan indole-lyase with extremely absolute stereospecificity, can change the stereospecificity in concentrated diammonium hydrogenphosphate solution. While tryptophanase is not inert to D-serine in the absence of diammonium hydrogenphosphate, it can undergo L-tryptophan synthesis from D-serine along with indole in the presence of it. It has been well known that tryptophana...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Biochemical journal
دوره 57 3 شماره
صفحات -
تاریخ انتشار 1954