Propionylation has been identified recently as a new type of protein post-translational modification. Bacterial propionyl-CoA synthetase and human histone H4 are propionylated at specific lysine residues that have been known previously to be acetylated. However, other proteins subject to this modification remain to ...

Propionyl-CoA is an intermediate metabolite produced through a variety of pathways including thioesterification of propionate and catabolism of odd chain fatty acids and select amino acids. Previously, we found that disruption of the methylcitrate synthase gene, mcsA, which blocks propionyl-CoA utilization, as well as growth on propionate impaired ...

The pathway of autotrophic CO₂ fixation was studied in the phototrophic bacterium Chloroflexus aurantiacus and in the aerobic thermoacidophilic archaeon Metallosphaera sedula. In both organisms, none of the key enzymes of the reductive pentose phosphate cycle, the reductive citric acid cycle, and the reductive acetyl coenzyme A ...

The invention relates to the discovery of a class of neutral acetylated ether-linked glycerolipids having the capacity to lower blood pressure in warm-blooded animals. This physiological effect is structure sensitive requiring a long chain alkyl group at the sn-1 position and a short carbon chain acyl group (acetyl or propionyl) at the ...

From the flowers of ARNICA CHAMISSONIS L ESS, sub-sp. FOLIOSA (N UTT.) M AGUIRE and its variety INCANA (G RAY) H ULTEN two new naturally occuring pseudoguaianolides were isolated and their structures established by spectroscopic methods. They are shown to be 4-O-acetyl-6-desoxychamissonolide ( 3) and the propionylic ester of 11,13-dihydrohelenalin which ...

A single local injection of 2.5 umoles of N-hydroxy-N-formyl-2-aminofluorene (N-hydroxy-FAF), N-hydroxy-N-acetyl-2-aminofluorene (N-hydroxy-AAF), or N-hydroxy-N-propionyl-2-aminofluorene (N-hydroxy-PAF) to each of the six left mammary glands of female Spr...

The phototrophic bacterium Chloroflexus aurantiacus uses a yet unsolved 3-hydroxypropionate cycle for autotrophic CO(2) fixation. It starts from acetyl-CoA, with acetyl-CoA and propionyl-CoA carboxylases acting as carboxylating enzymes. In a first cycle, (S)-malyl-CoA is formed from acetyl-CoA and 2 molecules of ...

The phototrophic bacterium Chloroflexus aurantiacus uses a yet unsolved 3-hydroxypropionate cycle for autotrophic CO₂ fixation. It starts from acetyl-CoA, with acetyl-CoA and propionyl-CoA carboxylases acting as carboxylating enzymes. In a first cycle, (S)-malyl-CoA is formed from acetyl-CoA ...

The first committed step of fatty acid and polyketides biosynthesis, the biotin-dependent carboxylation of an acyl-CoA, is catalyzed by acyl-CoA carboxylases (ACCases) such as acetyl-CoA carboxylase (ACC) and propionyl-CoA carboxylase (PCC). ACC and PCC in Streptomyces coelicolor are homologues multisubunit complexes that can carboxylate different short ...

N-Acetyl-D-neuraminic acid (NeuNAc) aldolase is an important enzyme for the metabolic engineering of cell-surface NeuNAc using chemically modified D-mannosamines. To explore the optimal substrates for this application, eight N-acyl derivatives of D-mannosamine were prepared, and their accessibility to NeuNAc aldolase was quantitatively investigated. The ...

The dissociative photoionization onsets for the formation of the propionyl ion (C(2)H(5)CO(+)) and the acetyl ion (CH(3)CO(+)) were measured from energy selected butanone and 2,3-pentanedione ions using the technique of threshold photoelectron photoion coincidence (TPEPICO) spectroscopy. Ion time-of-flight (TOF) mass spectra recorded as a function of the ...

Biotin has a profound effect on the metabolism of rhizobia. It is reported here that the activities of the biotin-dependent enzymes acetyl-coenzyme A carboxylase (ACC; EC 6.4.1.2) and propionyl-coenzyme A carboxylase (PCC; EC 6.4.1.3) are present in all species of the five genera comprising the Rhizobiaceae which were examined. Evidence is presented that ...

We investigated the interrelations between C(4) ketogenesis (production of beta-hydroxybutyrate + acetoacetate), C(5) ketogenesis (production of beta-hydroxypentanoate + beta-ketopentanoate), and anaplerosis in isolated rat livers perfused with (13)C-labeled octanoate, heptanoate, or propionate. Mass isotopomer analysis of C(4) and C(5) ketone bodies and of related acyl-CoA esters reveal that C(4) ...

The activities of four biotin enzymes, acetyl-coenzyme A (CoA) carboxylase, 3-methylcrotonyl-CoA carboxylase, pyruvate carboxylase, and propionyl-CoA carboxylase, and the accumulation of six biotin-containing polypeptides were determined during development of somatic embryos of carrot (Daucus carota). Acetyl-CoA carboxylase activity ...

The carbon monoxide dehydrogenase (CODH) complex from Methanosarcina thermophila catalyzed the synthesis of acetyl coenzyme A (acetyl-CoA) from CH3I, CO, and coenzyme A (CoA) at a rate of 65 nmol/min/mg at 55 degrees C. The reaction ended after 5 min with the synthesis of 52 nmol of acetyl-CoA per nmol of CODH complex. The optimum ...

The carbon monoxide dehydrogenase (CODH) complex from Methanosarcina thermophila catalyzed the synthesis of acetyl coenzyme A (acetyl-CoA) from CH3I, CO, and coenzyme A (CoA) at a rate of 65 nmol/min/mg at 55 degrees C. The reaction ended after 5 min with the synthesis of 52 nmol of acetyl-CoA per nmol of CODH complex. The optimum ...

and acetylcholinesterase (AChE) in central nerve endings, a high affinity choline uptake, and cytoplasmic choline activities [acetyl- (AChE), butyryl- (BChE), and propionyl- (PChE) cholinesterase] were assayed in parallel.70 PO 82.27 � 12.94 92.40 � 10.23 93.83 � 18.33 AChE OL 131.46 � 16.24 141.74 � 11.00 117.82 � 22

The autotrophic CO2 fixation pathway in Acidianus brierleyi, a facultatively anaerobic thermoacidophilic archaebacterium, was investigated by measuring enzymatic activities from autotrophic, mixotrophic, and heterotrophic cultures. Contrary to the published report that the reductive tricarboxylic acid cycle operates in A. brierleyi, the enzymatic activity of ATP:citrate lyase, the key enzyme of ...

The Streptomyces mycarofaciens mdmB gene encodes a 3-O-acyltransferase that catalyzes the addition of acetyl and propionyl groups to position 3 of the lactone ring in 16-member macrolide antibiotics like midecamycin and spiramycin. A putative O-methyltransferase gene (mdmC) is immediately downstream of mdmB, and both of these genes are closely linked to ...

The activation of pyruvate dehydrogenasea kinase activity by CoA esters has been further characterized. Half-maximal activation of kinase activity was achieved with about 1.0 microM acetyl-CoA after a 20-s preincubation in the presence of NADH. More than 80% of the acetyl-CoA was consumed during this period in acetylating sites in the ...

The enzymic hydrolysis of S-acyl glutathione has been observed in extracts of various plant tissues. The richest source found in this study was avocado mesocarp. No enzymic activity was observed with acetyl coenzyme A or acetylthiocholine as substrates. Hydrolytic activity was essentially constant in the pH range 7 to 9. There was a break in the activation energy plot at 25 C ...

A method is described for treating a warm-blooded animal comprising administering to the animal a neutral glycerolipid with a 12 to 20 carbon alkyl group at the sn-1 position, a short carbon chain acyl group at the sn-2 position and a hydroxyl group at the sn-3 position in an amount sufficient to lower the arterial blood pressure of the animal. A method is also described for treating a ...

The metabolic pathway for 1-alkyl-2-acetyl-sn-glycerols, a recently discovered biologically active neutral lipid class, was elucidated in experiments conducted with rabbit platelets. The total lipid extract obtained from platelets incubated with 1-(1-,2-/sup 3/H)alkyl-2-acetyl-sn-glycerols or 1-alkyl-2-(/sup 3/H)acetyl-sn-glycerols ...

Murine mAbs that were produced by immunization with a vaccine containing the N-propionyl derivative of Neisseria meningitidis group B (MenB) capsular polysaccharide (NPr MBPS) mediate protective responses against MenB but were not reactive with unmodified MBPS or chemically identical human polysialic acid (PSA). Recently, we showed that some of the mAbs were reactive with MBPS ...

Murine monoclonal antibodies (mAbs) that were produced by immunization with a vaccine containing the N-propionyl derivative of Neisseria meningitidis group B (MenB) capsular polysaccharide (NPr MBPS) mediate protective responses against MenB but were not reactive with unmodified MBPS or chemically identical human polysialic acid (PSA). Recently, we showed that some of the mAbs ...

The 3-hydroxypropionate cycle, a pathway for autotrophic carbon dioxide fixation, is reviewed with special emphasis on the biochemistry of CO2 fixing enzymes in Acidianus brierleyi, a thermophilic and acidophilic archeon. In the 3-hydroxypropionate cycle, two enzymes, acetyl-CoA carboxylase and propionyl-CoA carboxylase, catalyze CO2 fixation. It has been ...

We identified the first prokaryotic urea carboxylase (UCA) from a member of the alpha subclass of the class Proteobacteria, Oleomonas sagaranensis. This enzyme (O. sagaranensis Uca) was composed of 1,171 amino acids, and its N-terminal region resembled the biotin carboxylase domains of various biotin-dependent carboxylases. The C-terminal region of the enzyme harbored the Met-Lys-Met motif found ...

We identified the first prokaryotic urea carboxylase (UCA) from a member of the alpha subclass of the class Proteobacteria, Oleomonas sagaranensis. This enzyme (O. sagaranensis Uca) was composed of 1,171 amino acids, and its N-terminal region resembled the biotin carboxylase domains of various biotin-dependent carboxylases. The C-terminal region of the enzyme harbored the Met-Lys-Met motif found ...

We previously identified the prpBCDE operon, which encodes catabolic functions required for propionate catabolism in Salmonella typhimurium. Results from ¹³C-labeling experiments have identified the route of propionate breakdown and determined the biochemical role of each Prp enzyme in this pathway. The identification of catabolites accumulating in wild-type and mutant ...

A 3-hydroxypropionate/4-hydroxybutyrate cycle operates in autotrophic CO₂ fixation in various Crenarchaea, as studied in some detail in Metallosphaera sedula. This cycle and the autotrophic 3-hydroxypropionate cycle in Chloroflexus aurantiacus have in common the conversion of acetyl-coenzyme A (CoA) and two bicarbonates via 3-hydroxypropionate to ...

Several experimental studies have shown that levocarnitine reduces myocardial injury after ischemia and reperfusion by counteracting the toxic effect of high levels of free fatty acids, which occur in ischemia, and by improving carbohydrate metabolism. In addition to increasing the rate of fatty acid transport into mitochondria, levocarnitine reduces the intramitochondrial ratio of ...

The autotrophic CO₂ fixation pathway (3-hydroxypropionate cycle) in Chloroflexus aurantiacus results in the fixation of two molecules of bicarbonate into one molecule of glyoxylate. Glyoxylate conversion to the CO₂ acceptor molecule acetyl-coenzyme A (CoA) requires condensation with propionyl-CoA (derived from ...

In vivo ¹³C and ³¹P nuclear magnetic resonance techniques were used to study propionate metabolism by activated sludge in enhanced biological phosphorus removal systems. The fate of label supplied in [3-¹³C]propionate was monitored in living cells subjected to anaerobic/aerobic cycles. During the anaerobic phase, propionate was ...

The genetic operon for propionic acid degradation in Salmonella enterica serovar Typhimurium contains an open reading frame designated prpE which encodes a propionyl coenzyme A (propionyl-CoA) synthetase (A. R. Horswill and J. C. Escalante-Semerena, Microbiology 145:1381�1388, 1999). In this paper we report the cloning of prpE by PCR, its overexpression ...

Acyl peroxy nitrates (APNs) are an important class of reactive nitrogen species formed as a result of photochemical processing of hydrocarbons in the presence of NOx (NOx = NO+NO2). Measurements of speciated acyl peroxy nitrates (APNs) were made from August-October 2007 on a ponderosa pine plantation in the Sierra Nevada Mountains of California during the Biosphere Effects on AeRosols and ...

The present work illustrated an accurate GC/MS measurement for the low isotopomer enrichment assay of formic acid, acetic acid, propionic aicd, butyric acid, and pentanoic acid. The pentafluorobenzyl bromide derivatives of these very short chain fatty acids have high sensitivity of isotopoic enrichment due to their low natural isotopomer distribution in negative chemical ionization mass ...

We investigated the interrelations between C₄ ketogenesis (production of ?-hydroxybutyrate + acetoacetate), C₅ ketogenesis (production of ?-hydroxypentanoate + ?-ketopentanoate), and anaplerosis in isolated rat livers perfused with ¹³C-labeled octanoate, heptanoate, or propionate. Mass isotopomer analysis of ...

In this study, the product of the CIT3 gene has been identified as a dual specificity mitochondrial citrate and methylcitrate synthase and that of the CIT1 gene as a specific citrate synthase. Recombinant Cit1p had catalytic activity only with acetyl-CoA whereas Cit3p had similar catalytic efficiency with both acetyl-CoA and ...

The essential oil from mature leaves of flowering peppermint (Mentha piperita L.) contains up to 15% (�)-menthyl acetate, and leaf discs converted exogenous (�)-[G-³H]menthol into this ester in approximately 15% yield of the incorporated precursor. Leaf extracts catalyzed the acetyl coenzyme A-dependent acetylation of ...