scholarly journals The separation of vanillate o-demethylase from protocatechuate 3,4-oxygenase by ultracentrifugation

1967 ◽  
Vol 105 (2) ◽  
pp. 767-770 ◽  
Author(s):  
N. J. Cartwright ◽  
J. A. Buswell
Keyword(s):  
Pseudomonas Fluorescens ◽  
Formaldehyde Dehydrogenase ◽  
Cell Free Extract ◽  
Methyl Group ◽  
Oxidative Demethylation ◽  
A Cell ◽  
Trapping Agent ◽  
Soluble Part

1. Protocatechuate 3,4-oxygenase in the soluble part of a cell-free extract of Pseudomonas fluorescens (strain T) sedimented more rapidly than vanillate O-demethylase under specified conditions in a preparative ultracentrifuge. 2. The supernatant from this process contained vanillate O-demethylase and formaldehyde dehydrogenase, and when supplemented with NADH oxidized vanillate with an uptake of 1 mole of oxygen/mole of substrate and accumulation of protocatechuate. 3. This uptake was decreased to 0·5mole/mole of substrate in the presence of semicarbazide as trapping agent for formaldehyde. 4. Reasons are presented for the process of methyl group removal from vanillate being oxidative demethylation.

scholarly journals Bacterial attack on phenolic ethers: An enzyme system demethylating vanillic acid

1967 ◽  
Vol 102 (3) ◽  
pp. 826-841 ◽  
Author(s):  
N. J. Cartwright ◽  
A. R. W. Smith
Keyword(s):  
Formate Dehydrogenase ◽  
Soluble Fraction ◽  
Enzyme System ◽  
Reduced Glutathione ◽  
Ring Cleavage ◽  
Formaldehyde Dehydrogenase ◽  
Free System ◽  
Methyl Group ◽  
Oxidative Demethylation ◽  
A Cell

1. A cell-free system from Pseudomonas fluorescens catalysed the oxidative demethylation and subsequent ring-cleavage of vanillate, with uptake of 2.5 moles of oxygen/mole of substrate. 2. Demethylation involved absorption of 0.5 mole of oxygen/mole, and required reduced glutathione (GSH) and nucleotide (probably NADPH) as cofactors, with further possible requirements, the natures of which are discussed. 3. Incomplete evidence suggested that the aromatic ring was opened via protocatechuate and the appropriate oxygenase, with absorption of 1 mole of oxygen/mole of substrate, eventually yielding beta-oxoadipate. 4. The methyl group was removed sequentially as formaldehyde, formate and carbon dioxide, the steps catalysed respectively by formaldehyde dehydrogenase, which required GSH and NAD(+), and formate dehydrogenase. Each enzyme was cytochrome-linked and accounted for absorption of 0.5mole of oxygen/mole of substrate. 5. All enzymes except formate dehydrogenase, which was a cell-wall enzyme, resided in the soluble fraction of the extract. The demethylase could not be resolved because of unknown cofactor requirements.

The translation of rabbit hemoglobin messenger RNA in a cell-free extract from chick embryo brain

1974 ◽  
Vol 36 (2) ◽  
pp. 299-310 ◽  
Author(s):  
Don Hendrick ◽  
Walter Knöchel ◽  
Walter Schwarz ◽  
Sabine Pitzel ◽  
Heinz Tiedemann
Keyword(s):  
Chick Embryo ◽  
Messenger Rna ◽  
Cell Free Extract ◽  
A Cell ◽  
Embryo Brain

Antioxidant activity of selenium nanoparticles biosynthesized using a cell-free extract of Geobacillus

2020 ◽  
Vol 102 (10) ◽  
pp. 556-567
Author(s):  
Awanish Kumar ◽  
Bablu Prasad ◽  
Jayanand Manjhi ◽  
Kumar Suranjit Prasad
Keyword(s):  
Antioxidant Activity ◽  
Selenium Nanoparticles ◽  
Cell Free Extract ◽  
A Cell

scholarly journals The enzymic conversion of squalene, 2(3),22(23)-diepoxide to α-onocerin by a cell-free extract of Ononis spinosa

FEBS Letters ◽  
1971 ◽  
Vol 12 (4) ◽  
pp. 229-232 ◽  
Author(s):  
M.G. Rowan ◽  
P.D.G. Dean ◽  
T.W. Goodwin
Keyword(s):  
Cell Free Extract ◽  
A Cell

Evidence for cellular control in the synthesis of acetoin or α-ketoisovaleric acid by microorganisms

1974 ◽  
Vol 20 (6) ◽  
pp. 805-811 ◽  
Author(s):  
E. B. Collins ◽  
R. A. Speckman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Steady State ◽  
Serratia Marcescens ◽  
Lactobacillus Casei ◽  
Optically Active ◽  
Cell Free Extract ◽  
Data Support ◽  
A Cell ◽  
Cellular Control ◽  
Spent Media

Commercial α-acetolactate at pH 4.5 decarboxylated nonenzymatically (5 to 8%/h) to acetoin (69%) and diacetyl (31%), and an extract of Streptococcus diacetilactis 18-16 produced α-acetolactate (in addition to acetoin and diacetyl) from pyruvate in the presence of TPP and MgSO4. Nevertheless, α-acetolactate was not dispersed into media by any of four microorganisms (S. diacetilactis, strains 18-16 and DRC1, Saccharomyces cerevisiae 299, and Lactobacillus casei 393) that produced diacetyl and acetoin or by one (Serratia marcescens) that produced only acetoin. Lactobacillus casei and S. diacetilactis 18-16 produced unknown compounds that falsely indicated the presence of α-acetolactate when tests were made without separating acetoin and diacetyl from other components of the spent media. The production of acetoin by S. diacetilactis 18-16 was not inhibited by valine, the acetoin produced by this organism was optically active (+101.0°), and a cell-free extract of S. marcescens did not produce diacetyl while producing a large amount of acetoin. Data support the conclusion that the conversion of pyruvate to acetoin by some microorganisms and to α-ketoisovaleric acid by others is enzymatic and under cellular control, resulting in the synthesis of only steady-state amounts of enzymatically bound α-acetolactate in each of the pathways.

Conversion of17O/18O-labelled δ-(L-α-aminoadipyl)–L-cycteinyl–D-valine into17O/18O-labelled isopenicillin N in a cell-free extract of C. acremonium

1982 ◽  
pp. 137-139 ◽  
Author(s):  
Robert M. Adlington ◽  
Robin T. Aplin ◽  
Jack E. Baldwin ◽  
Leslie D. Field ◽  
Eeva-M. M. John ◽  
...  
Keyword(s):  
Cell Free Extract ◽  
A Cell ◽  
Isopenicillin N
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