Purification and characterization of the pyruvate-ferredoxin oxidoreductase from Clostridium acetobutylicum

1989 ◽  
Vol 152 (3) ◽  
pp. 244-250 ◽  
Author(s):  
B. Meinecke ◽  
J. Bertram ◽  
G. Gottschalk
Keyword(s):  
Clostridium Acetobutylicum ◽  
Purification And Characterization ◽  
Ferredoxin Oxidoreductase ◽  
Pyruvate Ferredoxin Oxidoreductase

scholarly journals Purification and characterization of pyruvate: ferredoxin oxidoreductase from the anaerobic protozoon Trichomonas vaginalis

1987 ◽  
Vol 246 (2) ◽  
pp. 529-536 ◽  
Author(s):  
K Williams ◽  
P N Lowe ◽  
P F Leadlay
Keyword(s):  
Trichomonas Vaginalis ◽  
Salting Out ◽  
Iron Protein ◽  
Ferredoxin Oxidoreductase ◽  
Membrane Bound ◽  
Pyruvate Ferredoxin Oxidoreductase ◽  
Bacterial Sources ◽  
Sepharose 4B ◽  
Thiamin Pyrophosphate

The pyruvate: ferredoxin oxidoreductase from the anaerobic protozoon Trichomonas vaginalis is an extrinsic protein bound to the hydrogenosomal membrane. It has been solubilized and purified to homogeneity, principally by salting-out chromatography on Sepharose 4B. Low recoveries of active enzyme were caused by inactivation by O2 and the irreversible loss of thiamin pyrophosphate. It is a dimeric enzyme of overall Mr 240,000 and subunit Mr 120,000. The enzyme contains, per mol of dimer, 7.3 +/- 0.3 mol of iron and 5.9 +/- 0.9 mol of acid-labile sulphur, suggesting the presence of two [4Fe-4S] centres, and 0.47 mol of thiamin pyrophosphate. The absorption spectrum of the enzyme is characteristic of a non-haem iron protein. The pyruvate: ferredoxin oxidoreductase from T. vaginalis is therefore broadly similar to the 2-oxo acid: ferredoxin (flavodoxin) oxidoreductases purified from bacterial sources, except that it is membrane-bound.

Purification and characterization of an α-L-arabinofuranosidase from Clostridium acetobutylicum ATCC 824

1987 ◽  
Vol 33 (11) ◽  
pp. 1011-1016 ◽  
Author(s):  
S. F. Lee ◽  
C. W. Forsberg
Keyword(s):  
Clostridium Acetobutylicum ◽  
Culture Fluid ◽  
Purification And Characterization ◽  
Ph Optimum ◽  
Rate Of Hydrolysis ◽  
Single Polypeptide ◽  
Hydrolysis Of ◽  
Clostridium Acetobutylicum Atcc 824 ◽  
Oat Spelt

An α-L-arabinofuranosidase (EC 3.2.1.55) has been purified from the extracellular culture fluid of Clostridium acetobutylicum ATCC 824 and characterized. The enzyme was a single polypeptide with a molecular weight of 94 000, an isoelectric point of 8.15, and a pH optimum between pH 5.0 and 5.5. The Km and Vmax values for p-nitrophenyl-α-L-arabinofuranoside were 4.0 mM and 36.4 μmol∙min−1·mg protein−1, respectively. The enzyme had practically no activity against other p-nitrophenylglycosides with the exception of p-nitrophenyl-α-D-glucoside which it hydrolysed at 9% of the rate exhibited on p-nitrophenyl-α-L-arabinofuranoside. It degraded arabinan in an exo-manner, but exhibited no activity on carboxymethylcellulose, arabinogalactan, arabinoxylan, or oat spelt xylan. However, when it was incubated with the purified xylanase B, also obtained from C. acetobutylicum, it acted cooperatively to increase the rate of hydrolysis of oat spelt xylan. Arabinose was detected as one of the hydrolysis products.

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