Acetate formation from CO and CO2 by cell extracts of Peptostreptococcus productus (strain Marburg)

1991 ◽  
Vol 156 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Kesen Ma ◽  
Gert Wohlfarth ◽  
Gabriele Diekert
Keyword(s):  
Cell Extracts ◽  
Acetate Formation ◽  
Peptostreptococcus Productus

scholarly journals Metabolic Analysis of Escherichia coliin the Presence and Absence of the Carboxylating Enzymes Phosphoenolpyruvate Carboxylase and Pyruvate Carboxylase

2000 ◽  
Vol 66 (5) ◽  
pp. 1844-1850 ◽  
Author(s):  
R. R. Gokarn ◽  
M. A. Eiteman ◽  
E. Altman
Keyword(s):  
Phosphoenolpyruvate Carboxylase ◽  
Pyruvate Carboxylase ◽  
Glucose Consumption ◽  
Molar Ratio ◽  
Specific Rate ◽  
Glucose Consumption Rate ◽  
E Coli ◽  
Cell Extracts ◽  
Acetate Formation ◽  
Important Position

ABSTRACT Fermentation patterns of Escherichia coli with and without the phosphoenolpyruvate carboxylase (PPC) and pyruvate carboxylase (PYC) enzymes were compared under anaerobic conditions with glucose as a carbon source. Time profiles of glucose and fermentation product concentrations were determined and used to calculate metabolic fluxes through central carbon pathways during exponential cell growth. The presence of the Rhizobium etli pyc gene in E. coli (JCL1242/pTrc99A-pyc) restored the succinate producing ability of E. coli ppc null mutants (JCL1242), with PYC competing favorably with both pyruvate formate lyase and lactate dehydrogenase. Succinate formation was slightly greater by JCL1242/pTrc99A-pyc than by cells which overproduced PPC (JCL1242/pPC201, ppc +), even though PPC activity in cell extracts of JCL1242/pPC201 (ppc +) was 40-fold greater than PYC activity in extracts of JCL1242/pTrc99a-pyc. Flux calculations indicate that during anaerobic metabolism the pyc +strain had a 34% greater specific glucose consumption rate, a 37% greater specific rate of ATP formation, and a 6% greater specific growth rate compared to the ppc + strain. In light of the important position of pyruvate at the juncture of NADH-generating pathways and NADH-dissimilating branches, the results show that when PPC or PYC is expressed, the metabolic network adapts by altering the flux to lactate and the molar ratio of ethanol to acetate formation.

scholarly journals Sodium dependent acetate formation from CO2 in Peptostreptococcus productus (strain Marburg)

1989 ◽  
Vol 57 (3) ◽  
pp. 353-357 ◽  
Author(s):  
Gabriele Geerligs ◽  
Peter Schönheit ◽  
Gabriele Diekert
Keyword(s):  
Sodium Dependent ◽  
Acetate Formation ◽  
Peptostreptococcus Productus

scholarly journals Inhibition of Anaerobic Phosphate Release by Nitric Oxide in Activated Sludge

1998 ◽  
Vol 64 (8) ◽  
pp. 2925-2930 ◽  
Author(s):  
E. W. J. Van Niel ◽  
K. J. Appeldoorn ◽  
A. J. B. Zehnder ◽  
G. J. J. Kortstee
Keyword(s):  
Nitric Oxide ◽  
Activated Sludge ◽  
Adenylate Kinase ◽  
Dry Weight ◽  
Inhibitory Effect ◽  
Phosphate Removal ◽  
Phosphate Release ◽  
Cell Extracts ◽  
Acetate Formation ◽  
Nitrate And Nitrite

ABSTRACT Activated sludge not containing significant numbers of denitrifying, polyphosphate [poly(P)]-accumulating bacteria was grown in a fill-and-draw system and exposed to alternating anaerobic and aerobic periods. During the aerobic period, poly(P) accumulated up to 100 mg of P · g of (dry) weight. When portions of the sludge were incubated anaerobically in the presence of acetate, 80 to 90% of the intracellular poly(P) was degraded and released as orthophosphate. Degradation of poly(P) was mainly catalyzed by the concerted action of polyphosphate:AMP phosphotransferase and adenylate kinase, resulting in ATP formation. In the presence of 0.3 mM nitric oxide (NO) in the liquid-phase release of phosphate, uptake of acetate, formation of poly-β-hydroxybutyrate, utilization of glycogen, and formation of ATP were severely inhibited or completely abolished. In cell extracts of the sludge, adenylate kinase activity was completely inhibited by 0.15 mM NO. The nature of this inhibition was probably noncompetitive, similar to that with hog adenylate kinase. Activated sludge polyphosphate glucokinase was also completely inhibited by 0.15 mM NO. It is concluded that the inhibitory effect of NO on acetate-mediated phosphate release by the sludge used in this study is due to the inhibition of adenylate kinase in the phosphate-releasing organisms. The inhibitory effect of nitrate and nitrite on phosphate release is probably due to their conversion to NO. The lack of any inhibitory effect of NO on adenylate kinase of the poly(P)-accumulatingAcinetobacter johnsonii 210A suggests that this type of organism is not involved in the enhanced biological phosphate removal by the sludges used.

In vivo Production of Soluble Inorganic Pyrophosphatases in Two Strains of Vibrio cholerae

1970 ◽  
Vol 24 (1) ◽  
pp. 38-41
Author(s):  
Taslima Taher Lina ◽  
Mohammad Ilias
Keyword(s):  
Vibrio Cholerae ◽  
Specific Activity ◽  
Experimental Conditions ◽  
Environmental Strain ◽  
Cell Extracts ◽  
Atcc Strain ◽  
The Family ◽  
Effects Of Ph ◽  
Vibrio Cholerae O1

The in vivo production of soluble inorganic pyrophosphatases (PPases) was investigated in two strains, namely, Vibrio cholerae EM 004 (environmental strain) and Vibrio cholerae O1 757 (ATCC strain). V. cholerae is known to contain both family I and family II PPase coding sequences. The production of family I and family II PPases were determined by measuring the enzyme activity in cell extracts. The effects of pH, temperature, salinity of the growth medium on the production of soluble PPases were studied. In case of family I PPase, V. cholerae EM 004 gave the highest specific activity at pH 9.0, with 2% NaCl + 0.011% NaF and at 37°C. The strain V. cholerae O1 757 gave the highest specific activity at pH 9.0, with media containing 0% NaCl and at 37°C. On the other hand, under all the conditions family II PPase did not give any significant specific activity, suggesting that the family II PPase was not produced in vivo in either strains of V. cholerae under different experimental conditions. Keywords: Vibrio cholerae, Pyrophosphatases (PPases), Specific activityDOI: http://dx.doi.org/10.3329/bjm.v24i1.1235 Bangladesh J Microbiol, Volume 24, Number 1, June 2007, pp 38-41

Enzymatic Activity Assays in Yeast Cell Extracts

BIO-PROTOCOL ◽  
2014 ◽  
Vol 4 (23) ◽  
Author(s):  
Melike Çağlayan ◽  
Samuel Wilson
Keyword(s):  
Enzymatic Activity ◽  
Yeast Cell ◽  
Cell Extracts

scholarly journals Isolation of a Gene Responsible for the Oxidation oftrans-Anethole topara-Anisaldehyde by Pseudomonas putida JYR-1 and Its Expression in Escherichia coli

2012 ◽  
Vol 78 (15) ◽  
pp. 5238-5246 ◽  
Author(s):  
Dongfei Han ◽  
Ji-Young Ryu ◽  
Robert A. Kanaly ◽  
Hor-Gil Hur
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Putida ◽  
Hypothetical Protein ◽  
Aldehyde Group ◽  
Agrobacterium Vitis ◽  
T7 Promoter ◽  
Content Type ◽  
E Coli ◽  
Cell Extracts ◽  
Isoeugenol Monooxygenase

ABSTRACTA plasmid, pTA163, inEscherichia colicontained an approximately 34-kb gene fragment fromPseudomonas putidaJYR-1 that included the genes responsible for the metabolism oftrans-anethole to protocatechuic acid. Three Tn5-disrupted open reading frame 10 (ORF 10) mutants of plasmid pTA163 lost their abilities to catalyzetrans-anethole. Heterologously expressed ORF 10 (1,047 nucleotides [nt]) under a T7 promoter inE. colicatalyzed oxidative cleavage of a propenyl group oftrans-anethole to an aldehyde group, resulting in the production ofpara-anisaldehyde, and this gene was designatedtao(trans-anetholeoxygenase). The deduced amino acid sequence of TAO had the highest identity (34%) to a hypothetical protein ofAgrobacterium vitisS4 and likely contained a flavin-binding site. Preferred incorporation of an oxygen molecule from water intop-anisaldehyde using18O-labeling experiments indicated stereo preference of TAO for hydrolysis of the epoxide group. Interestingly, unlike the narrow substrate range of isoeugenol monooxygenase fromPseudomonas putidaIE27 andPseudomonas nitroreducensJin1, TAO fromP. putidaJYR-1 catalyzed isoeugenol,O-methyl isoeugenol, and isosafrole, all of which contain the 2-propenyl functional group on the aromatic ring structure. Addition of NAD(P)H to the ultrafiltered cell extracts ofE. coli(pTA163) increased the activity of TAO. Due to the relaxed substrate range of TAO, it may be utilized for the production of various fragrance compounds from plant phenylpropanoids in the future.

scholarly journals Localization of DNA repair synthesis by human cell extracts to a short region at the site of a lesion

1989 ◽  
Vol 264 (36) ◽  
pp. 21788-21792
Author(s):  
J Hansson ◽  
M Munn ◽  
W D Rupp ◽  
R Kahn ◽  
R D Wood
Keyword(s):  
Dna Repair ◽  
Human Cell ◽  
Repair Synthesis ◽  
Short Region ◽  
Cell Extracts ◽  
Dna Repair Synthesis
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