This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Sagers, R. D. Articles by Gunsalus, I. C. Search for Related Content PubMed PubMed Citation Articles by Sagers, R. D. Articles by Gunsalus, I. C.

 Previous Article  |  Next Article 

J Bacteriol. 1961 August; 82(2): 233-238
Copyright ©, 1961, The Williams & Wilkins Company. All Rights Reserved.

ACETATE FORMATION IN CLOSTRIDIUM ACIDI-URICI: ACETOKINASE

^a Department of Chemistry and Chemical Engineering, University of Illinois, Urbana, Illinois

ABSTRACT

SAGERS, RICHARD D. (University of Illinois, Urbana), MOSHE BENZIMAN, AND I. C. GUNSALUS. Acetate formation in Clostridium acidiurici: Acetokinase. J. Bacteriol. 82:233–238. 1961.—To define the energy-yielding reaction(s) during fermentation of purines by Clostridium acidi-urici, an eightfold purified acetokinase was obtained by protamine and ammonium sulfate fractionation of crude extracts. Enzyme activity was determined by measuring the disappearance of acetyl phosphate using adenosine diphosphate (ADP) as phosphate acceptor or by following the generation of acetyl phosphate from adenosine triphosphate (ATP) + acetate. The optimal pH for the reaction was observed to be 7.4. K_m values for acetyl phosphate, ADP, and magnesium ions were shown to be 2.1 x 10^–3M, 3.2 x 10^–3M, and 2.4 x 10^–3M, respectively. Acetyl phosphate disappearance is dependent upon ADP and is stoichiometric with addition of the latter. The acetokinase reaction probably represents the major energy-yielding reaction during purine fermentation by this organism. A pathway for acetate generation from formiminoglycine is proposed, and evidence for a number of enzyme activities intermediate between formiminoglycine degradation and acetate formation is given. The enzyme activities demonstrated are compatible with the over-all purine fermentation rate by whole cells.

¹ Present address: Department of Bacteriology, Brigham Young University, Provo, Utah.

² Present address: Department of Biological Chemistry, Hebrew University, Jerusalem, Israel.