scholarly journals Studies on Aerobacillus Polymyxa V. The Significance of the Michaelis Constants of the Hydrogeni.Yase Systems and Related Enzymes

1953 ◽  
Vol 6 (2) ◽  
pp. 198 ◽  
Author(s):  
WG Crewther
Keyword(s):  
Molecular Hydrogen ◽  
Cell Suspensions ◽  
Washed Cell ◽  
Enzyme Systems ◽  
Km Value ◽  
Michaelis Constants

Washed-cell suspensions of Aerobacillu8 polymyxa have been used to determine the Michaelis constants of the enzyme systems producing molecular hydrogen from formate, glucose, and pyruvate and of the dehydrogenases acting on these substrates. For each substrate the Km value of the dehydrogenase was considerably smaller than for the analogous hydrogenlyase.

scholarly journals The synthesis of indole by washed cell suspensions of Escherichia coli

1956 ◽  
Vol 64 (1) ◽  
pp. 132-137 ◽  
Author(s):  
F. Gibson ◽  
Marjorie J. Jones ◽  
H. Teltscher
Keyword(s):  
Escherichia Coli ◽  
Cell Suspensions ◽  
Washed Cell

scholarly journals Effect of Linoleic Acid Concentration on Conjugated Linoleic Acid Production by Butyrivibrio fibrisolvensA38

2000 ◽  
Vol 66 (12) ◽  
pp. 5226-5230 ◽  
Author(s):  
Young Jun Kim ◽  
Rui Hai Liu ◽  
Daniel R. Bond ◽  
James B. Russell
Keyword(s):  
Linoleic Acid ◽  
Conjugated Linoleic Acid ◽  
Cell Density ◽  
Cell Suspensions ◽  
Bacterial Inactivation ◽  
Butyrivibrio Fibrisolvens ◽  
Washed Cell ◽  
Initial Cell ◽  
Normal Enzyme ◽  
Linoleic Acid Concentration

ABSTRACT Butyrivibrio fibrisolvens A38 inocula were inhibited by as little as 15 μM linoleic acid (LA), but growing cultures tolerated 10-fold more LA before growth was inhibited. Growing cultures did not produce significant amounts of cis-9, trans-11 conjugated linoleic acid (CLA) until the LA concentration was high enough to inhibit biohydrogenation, growth was inhibited, and lysis was enhanced. Washed-cell suspensions that were incubated anaerobically with 350 μM LA converted most of the LA to hydrogenated products, and little CLA was detected. When the washed-cell suspensions were incubated aerobically, biohydrogenation was inhibited, CLA production was at least twofold greater, and CLA persisted. The LA isomerase reaction was very rapid, but the LA isomerase did not recycle like a normal enzyme to catalyze more substrate. Cells that were preincubated with CLA lost their ability to produce more CLA from LA, and the CLA accumulation was directly proportional (r 2= 0.98) to the initial cell density. Growing cells were as sensitive to CLA as LA, the LA isomerase and reductases of biohydrogenation were linked, and free CLA was not released. Because growing cultures ofB. fibrisolvens A38 did not produce significant amounts of CLA until the LA concentration was high, biohydrogenation was arrested, and the cell density had declined, the flow of CLA from the rumen may be due to LA-dependent bacterial inactivation, death, or lysis.

scholarly journals Peptocoagulase: clotting factor produced by bovine strains of Peptococcus indolicus

1978 ◽  
Vol 7 (4) ◽  
pp. 361-367
Author(s):  
L M Switalski ◽  
O Schwam ◽  
C J Smyth ◽  
T Wadström
Keyword(s):  
Proteolytic Activity ◽  
Culture Filtrate ◽  
Esterase Activity ◽  
Methyl Esters ◽  
Cell Suspensions ◽  
Clinical Isolates ◽  
Clotting Factor ◽  
Stable Complex ◽  
Washed Cell ◽  
Stoichiometric Reaction

The production of a clotting factor (peptocoagulase) by bovine clinical isolates of Peptococcus indolicus and its nature were investigated. Extracellular peptocoagulase was demonstrated in culture filtrates of 93% and cell associated with washed cell suspensions of 100% of the 75 isolates tested. Both citrated and heparinized plasma were clotted. Crude peptocoagulase was nondialyzable, precipitated with (NH4)2SO4 at 40% saturation, somewhat resistant to heating at both neutral and acid pH, and chloroform insoluble. Culture filtrate did not contain proteolytic activity with albumin and casein, as substrates and no esterase activity was detected with tosylarginine and benzoylarginine methyl esters as substrates. The clotting reaction required peptocoagulase, prothrombin, and fibrinogen. The activation of prothrombin appeared to involve a stoichiometric reaction with peptocoagulase, possibly by formation of a stable complex.

Bacterial degradation of nitrilotriacetic acid (NTA)

1971 ◽  
Vol 17 (12) ◽  
pp. 1553-1556 ◽  
Author(s):  
D. D. Focht ◽  
H. A. Joseph
Keyword(s):  
Nitrilotriacetic Acid ◽  
Cell Suspensions ◽  
Bacterial Degradation ◽  
Nitroso Compounds ◽  
Sewage Effluent ◽  
Pseudomonas Sp ◽  
Total Conversion ◽  
Washed Cell ◽  
Resting Cell ◽  
Lag Period

Pseudomonas sp. was isolated from sewage effluent by elective culture with nitrilotriacetic acid (NTA) as its sole nitrogen and carbon source for growth. NTA-nitrogen was converted to biomass and ammonium by growing cultures with small quantities of nitrite (< 1 ppm) being produced. Washed cell suspensions degraded all of the NTA-nitrogen to ammonium before total conversion of the NTA-carbon to carbon dioxide and water. Resting cell suspensions grown from NTA oxidized NTA, aminodiacetic acid, and glycine immediately, whereas methylaminodiacetic acid was oxidized only after an adaptive lag period, and sarcosine was not oxidized at all. Oxidation of aminodiacetic acid was always more rapid than NTA. Nitrosamines or other nitroso compounds were not found in culture or resting cell supernatants incubated with NTA.

scholarly journals The oxidation of aminoacetone by a species of Arthrobacter

1968 ◽  
Vol 106 (1) ◽  
pp. 267-270 ◽  
Author(s):  
Margaret L. Green ◽  
J. B. Lewis
Keyword(s):  
Amine Oxidase ◽  
Sole Source ◽  
Cell Suspensions ◽  
Complete Disappearance ◽  
Complete Oxidation ◽  
Arthrobacter Globiformis ◽  
Washed Cell ◽  
Carbon And Nitrogen

1. A micro-organism similar to Arthrobacter globiformis has been isolated from sewage by elective growth on a medium containing l-threonine as sole source of carbon and nitrogen. 2. Washed cell suspensions of the organism catalyse the complete disappearance of aminoacetone from the medium and its almost complete oxidation. 3. In the presence of iodoacetate, aminoacetone disappearance is accompanied by the accumulation of methylglyoxal, about 70% of the aminoacetone removed being accounted for in this way. 4. It is suggested that the conversion of aminoacetone into methylglyoxal is catalysed by an amine oxidase.

scholarly journals Precursors of the pyrimidine moiety of thiamine

1968 ◽  
Vol 106 (1) ◽  
pp. 271-277 ◽  
Author(s):  
P. C. Newell ◽  
R G Tucker
Keyword(s):  
Amino Acid ◽  
Salmonella Typhimurium ◽  
Specific Radioactivity ◽  
Cell Suspensions ◽  
Pure Form ◽  
Washed Cell ◽  
Pyrimidine Moiety

1. A method was devised for obtaining the pyrimidine moiety of thiamine in a pure form after its excretion into the medium by de-repressed washed-cell suspensions of mutants of Salmonella typhimurium LT2. 2. By using amino acid-requiring mutants, this excretion of pyrimidine moiety was shown to be dependent on the presence of both methionine and glycine. 3. In the presence of either [Me−14C]methionine or [G−14C]methionine, methionine-requiring mutants did not incorporate radioactivity into the pyrimidine moiety. 4. In contrast, both [1−14C]glycine and [2−14C]glycine were incorporated into the pyrimidine moiety excreted by glycine-requiring mutants, and this occurred with little or no dilution of specific radioactivity. 5. The possible requirement for methionine as a cofactor and the significance of the incorporation of both carbon atoms of glycine are discussed.

Effect of pH on Acid Production from Sorbitol in Washed Cell Suspensions of Oral Bacteria

1990 ◽  
Vol 24 (2) ◽  
pp. 107-112 ◽  
Author(s):  
S. Kalfas ◽  
Y. Maki ◽  
D. Birkhed ◽  
S. Edwardsson
Keyword(s):  
Acid Production ◽  
Oral Bacteria ◽  
Cell Suspensions ◽  
Effect Of Ph ◽  
Washed Cell
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