Chemo- and stereoselective reductions are important reactions in chemistry biology, reductases from biological sources increasingly applied organic synthesis. In contrast, carboxylases used only sporadically. We recently described crotonyl-CoA carboxylase/reductase, which catalyzes the reduction of (E)-crotonyl-CoA to butyryl-CoA but also reductive carboxylation ethylmalonyl-CoA. this study, complete stereochemical course both was investigated detail. The pro-(4R) hydrogen NADPH is...

ABSTRACT The anaerobic metabolism of phenol in the beta-proteobacterium Thauera aromatica proceeds via carboxylation to 4-hydroxybenzoate and is initiated by ATP-dependent conversion phenylphosphate. subsequent para phenylphosphate catalyzed carboxylase, which was purified studied. This enzyme consists four proteins with molecular masses 54, 53, 18, 10 kDa, whose genes are located adjacent each other gene cluster codes for phenol-induced proteins. Three subunits (54, kDa) were sufficient...

A new pathway for aerobic benzoate oxidation has been postulated Azoarcus evansii and a Bacillus stearothermophilus-like strain. Benzoate is first transformed into benzoyl coenzyme (benzoyl-CoA), which subsequently oxidized to 3-hydroxyadipyl-CoA then 3-ketoadipyl-CoA; all intermediates are CoA thioesters. The genes coding this benzoate-induced were investigated in the beta-proteobacterium A. evansii. They identified on basis of N-terminal amino acid sequences purified metabolic enzymes...

Benzoyl‐coenzyme A is the most common central intermediate of anaerobic aromatic metabolism. Studies with whole cells different bacteria and in vitro had shown that benzoyl‐CoA reduced to alicyclic compounds, possibly via cyclohexadiene intermediates. This reaction considered a ‘biological Birch reduction’. We have elucidated by NMR techniques structures six products [ ring ‐ 13 C 6 ]benzoate reduction. The catalyzed extracts from denitrifying Pseudomonas strain K172 anaerobically grown...

Many aromatic compounds are anaerobically oxidized to CO 2 via benzoyl‐CoA as the common intermediate. In Thauera aromatica , central pathway comprises ATP‐driven two‐electron reduction of benzene ring; this reaction uses a ferredoxin electron donor and is catalyzed by reductase. The first intermediate, cyclohex‐1,5‐diene‐1‐carboxyl‐CoA, subsequently hydrated dienoyl‐CoA hydratase 6‐hydroxycyclohex‐1‐ene‐1‐carboxyl‐CoA. Formation main product produced cell extracts, 3‐hydroxypimelyl‐CoA,...

ABSTRACT Genes involved in the anaerobic metabolism of phenol denitrifying bacterium Thauera aromatica have been studied. The first two committed steps this appear to be phosphorylation phenylphosphate by an unknown phosphoryl donor (“phenylphosphate synthase”) and subsequent carboxylation 4-hydroxybenzoate under release phosphate carboxylase”). Both enzyme activities are strictly induced. Two-dimensional gel electrophoresis allowed identification several phenol-induced proteins. Based on...

4-Hydroxybenzoyl-CoA reductase catalyzes an important reaction in the anaerobic metabolism of phenolic compounds, i.e. reductive removal aromatic hydroxyl group. The prosthetic groups and natural electron donor enzyme were investigated genes cloned sequenced. is a molybdenum-flavin-iron-sulfur protein subunit composition alpha2beta2gamma2. It contains approximately 1.3 flavin nucleotide, probably FAD, 1.9 Mo, 15 Fe, 12.5 acid-labile sulfur. Sequence interpretation suggests that native two...

The initial step of anaerobic 4‐hydroxybenzoate and 3‐hydroxybenzoate degradation was studied in a denitrifying Pseudomonas sp. 4‐Hydroxybenzoate are converted into their coenzyme A (CoA) thioesters by two different specific ligases. 4‐Hydroxybenzoate‐CoA ligase (AMP‐forming) purified 350‐fold. is active as monomer molecular mass 48 kDa, determined gel filtration SDS/PAGE. At pH optimum 8.5, the apparent K m values for 4‐hydroxybenzoate, ATP, 37 μM, 77 125 respectively. enzyme reacts...

The initial reactions in anaerobic degradation of phenol to CO 2 have been studied vitro with a denitrifying Pseudomonas strain grown and nitrate the absence molecular oxygen. Phenol has proposed be carboxylated 4‐hydroxybenzoate [(1987) Arch. Microbiol. 148, 213–217]. 4‐Hydroxybenzoate was activated 4‐hydroxybenzoyl‐CoA by coenzyme A ligase. Cell extracts also catalyzed reductive dehydroxylation benzoyl‐CoA reduced benzyl viologen as electron donor. This enzyme, benzoyl‐CoA:(acceptor)...

In the aerobic metabolism of aromatic substrates, oxygenases use molecular oxygen to hydroxylate and finally cleave ring. case common intermediate benzoate, ring cleavage substrates are either catechol (in bacteria) or 3,4-dihydroxybenzoate (protocatechuate, mainly in fungi). We have shown before that many bacteria, e.g. Azoarcus evansii, organism studied here, a completely different mechanism. This elaborate pathway requires formation benzoyl-CoA, followed by an oxygenase reaction...

Under anoxic conditions most aromatic compounds are metabolized via benzoyl-CoA which becomes reduced by reductase (dearomatizing); this enzyme was recently described in the bacterium Thauera aromatica [Boll, M. & Fuchs, G. (1995) Eur. J. Biochem. 234, 921-933]. It catalyzes reaction + 2 e- H+ MgATP H2O --> cyclohexa-1,5-diene-1-carboxyl-CoA MgADP Pi. The iron-sulfur protein has a native molecular mass of 160-170 kDa and consists four different subunits. In addition flavin may be present....

ABSTRACT In the β-proteobacterium Azoarcus evansii , aerobic metabolism of 2-aminobenzoate (anthranilate), phenylacetate, and benzoate proceeds via three unprecedented pathways. The pathways have in common that all substrates are initially activated to coenzyme A (CoA) thioesters further processed this form. two initial steps catalyzed by a 2-aminobenzoate-CoA ligase forming 2-aminobenzoyl-CoA monooxygenase/reductase (ACMR) 2-amino-5-oxo-cyclohex-1-ene-1-carbonyl-CoA. Eight genes possibly...

Summary A new principle of aerobic aromatic metabolism has been postulated, which is in contrast to the known pathways. In various bacteria substrate benzoate first converted its coenzyme (CoA) thioester, benzoyl‐CoA, subsequently attacked by an oxygenase, followed a non‐oxygenolytic fission ring. We provide evidence for this hypothesis and show that benzoyl‐CoA conversion bacterium Azoarcus evansii requires NADPH, O 2 two protein components, BoxA BoxB. homodimeric 46 kDa...

Phenol is metabolized in a denitrifying bacterium the absence of molecular oxygen via para ‐carboxylation to 4‐hydroxybenzoate (biological Kolbe‐Schmitt synthesis). The enzyme system catalyzing presumptive carboxylation phenol, tentatively named ‘phenol carboxylase’, catalyzes an isotope exchange between 14 CO 2 and carboxyl group (specific activity 0.1 μmol incorporated into × min −1 mg cell protein) which considered partial reaction overall catalysis; C from [ C]phenol was not exchanged...

The aerobic catabolism of benzoate was studied in the Gram-negative proteobacterium Azoarcus evansii and Gram-positive bacterium Bacillus stearothermophilus. In contrast to earlier proposals, not converted into hydroxybenzoate or gentisate. Rather, benzoyl-CoA a product both microbial species under conditionsin vivo. Benzoyl-CoA various CoA thioesters by cell extracts oxygen- NADPH-dependent reactions. Using [ring-13C6]benzoyl-CoA as...

ABSTRACT The aerobic metabolism of benzoate in the proteobacterium Azoarcus evansii was reinvestigated. known pathways leading to catechol or protocatechuate do not operate this bacterium. presumed degradation via 3-hydroxybenzoyl-coenzyme A (CoA) and gentisate could be confirmed. first committed step is activation benzoyl-CoA by a specifically induced benzoate-CoA ligase (AMP forming). This enzyme purified shown differ from an isoenzyme catalyzing same reaction under anaerobic conditions....

Abstract Numeric time series is a class of data consisting chronologically ordered observations represented by numeric values. Much the in various domains, such as financial, medical and scientific, are form series. To cope with increasing sizes datasets, numerous approaches for abstracting large temporal developed area mining. Many them proved to be useful visualization. However, despite existence surveys on mining visualization, there no comprehensive classification existing methods based...

The cytoplasmic membrane of the methanogenic archaebacterium Methanobacterium thermoautotrophicum does not contain cytochromes, but did a corrinoid protein molecular mass about 33 kDa which, after treatment with 10 mg Triton X‐100/mg protein, was contained in complex 500 kDa. Washed membranes from 1 g dry cells 70 nmol cobamide factor III (5‐hydroxybenzimidazolyl cobamide) as sole corrinoid. corrinoid‐containing purified and some its properties were studied. According to several criteria it...

In a previous report we have described some properties of novel flavoenzyme from denitrifying Pseudomonas species which catalyzes the oxygen‐ and NAD(P)H‐dependent conversion 2‐aminobenzoyl‐CoA [Buder, R., Ziegler, K., Fuchs, G., Langkau, B. & Ghisla, S. (1989) Eur. J. Biochem. 185, 637–634]. this paper, on identification three products formed in reaction. The spectroscopic data chemical these compounds those their degradation are compatible with structures 2‐amino‐5‐hydroxybenzoyl‐CoA,...