Immunochemistry of bacterial ornithine carbamoyltransferase and bacterial arginase

1970 ◽  
Vol 7 (10) ◽  
pp. 873
Author(s):  
E. Soru ◽  
O. Zaharia
2004 ◽  
Vol 186 (11) ◽  
pp. 3653-3655 ◽  
Author(s):  
José Luis Hernández-Flores ◽  
Karina López-López ◽  
Rogelio Garcidueñas-Piña ◽  
Alba E. Jofre-Garfias ◽  
Ariel Alvarez-Morales

ABSTRACT In Pseudomonas syringae pv. phaseolicola the enzyme ornithine carbamoyltransferase (OCTase), encoded by argF, is negatively regulated by argR, similar to what has been reported for Pseudomonas aeruginosa. However, production of the phaseolotoxin-resistant OCTase encoded by argK, synthesis of phaseolotoxin, and infectivity for bean pods occur independently of the ArgR protein.


1995 ◽  
Vol 306 (3) ◽  
pp. 717-721 ◽  
Author(s):  
G Wu ◽  
N E Flynn ◽  
W Yan ◽  
D G Barstow

This study was designed to determine whether pyrroline-5-carboxylate (P-5-C) synthase is deficient in chick enterocytes therefore resulting in the lack of synthesis of ornithine and citrulline from glutamine. Post-weaning pig enterocytes, which are known to contain P-5-C synthase and to synthesize both ornithine and citrulline from glutamine, were used as positive controls. Enterocytes were incubated at 37 degrees C for 0-30 min in the presence of 2 mM [U-14C]glutamine or 2 mM ornithine plus 2 mM NH4Cl. In chick enterocytes, glutamine was metabolized to NH3, CO2, glutamate, alanine and aspartate, but not to ornithine, citrulline, arginine or proline. Likewise, there was no formation of citrulline, arginine, alanine or aspartate from ornithine in chick enterocytes. Furthermore, the rate of conversion of ornithine into proline in chick enterocytes was only about 4% of that in cells from pigs. To elucidate the reason for the inability of chick enterocytes to synthesize ornithine and citrulline from glutamine, the activities of the enzymes involved were measured. No activity of P-5-C synthase or ornithine carbamoyltransferase was found in chick enterocytes, in contrast with cells from post-weaning pigs. It was also demonstrated that the activity of ornithine aminotransferase in chick enterocytes was only 3% of that in cells from pigs. Thus the present findings elucidate the biochemical reason for the lack of endogenous synthesis of ornithine and citrulline in chicks. Our results also explain previous observations that ornithine cannot replace arginine or proline in the diet of chicks. We suggest that the absence of P-5-C synthase and ornithine carbamoyltransferase in enterocytes is the metabolic basis for the nutritional requirement of arginine in the chick.


2005 ◽  
Vol 122 (3) ◽  
pp. 501-509 ◽  
Author(s):  
Tetsuo MORITA ◽  
Satoshi MIURA ◽  
Masataka MORI ◽  
Masamiti TATIBANA

1974 ◽  
Vol 46 (1) ◽  
pp. 105-112
Author(s):  
J. E. Buttery ◽  
S. P. Parbhoo ◽  
D. N. Baron

1. Changes in the perfusate activities of aspartate transaminase, lactate dehydrogenase, its ‘LD-5’ component, sorbitol dehydrogenase, ornithine carbamoyltransferase, and the isoenzyme patterns of lactate dehydrogenase and aspartate transaminase, were investigated in eleven perfusions of pig liver with human blood in order to assess liver cell damage during perfusion. 2. The aspartate transaminase values were a sensitive indicator of liver damage provided that, as was usually the case, the degree of haemolysis was small. Appearance on electrophoresis of the mitochondrial isoenzyme of aspartate transaminase indicated severe liver damage. 3. Measurement of sorbitol dehydrogenase activity was also shown to be a sensitive index of liver cell damage, and had the advantage that haemolysis did not interfere. 4. Measurement of total lactate dehydrogenase activity was unreliable as this largely reflected the degree of haemolysis rather than liver cell damage. However, the isoenzyme pattern of lactate dehydrogenase on electrophoresis distinguished liver cell damage from haemolysis. The chemical determination of ‘LD-5’ was not a sensitive index of pig liver damage as this fraction is found only in low concentration in pig liver. 5. Ornithine carbamoyltransferase was also found not to be a sensitive marker of liver cell damage.


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