Terminal oxydation pattern of a soil Pseudomonad (PL-strain)

Summary The organism grown on ¹-p-menthene was found to grow without any lag on methyl isopropyl ketone, isobutyrate, succinate, malate, lactate and acetate. Isobutyrate or acetate grown cells grew on ¹-p-menthene after a lag and showed comparatively little growth on -isopropyl pimelic acid.¹-p-menthene grown cells oxidized readily isobutyrate, acetate, succinate, malate, -ketoglutarate and methacrylate. Methylmalonate, methyl isopropyl ketone and -isopropyl pimelic acid were rather oxidized at slow rates. Isobutyrate grown cells, on the other hand, showed from very good to very fair oxidation rates with succinate, isobutyrate, acetate, malate, methacrylate, -ketoglutarate. Methylmalonate was oxidized much better and methyl isopropyl ketone was oxidized slowly.¹-p-menthene and isobutyrate grown cells were used under resting conditions with different substrates in the presence of arsenite. Analysis of the reaction products indicated the accumulation of a keto acid. Qualitative analysis of the keto acid formed by TLC showed pyruvate as the major ketocarboxylic acid with one or two other minor components. The major component had been isolated and identified as pyruvic acid. Similar results had been obtained by working with crude cell-free enzyme preparations.Based on these results two possible mechanisms of degradation of isobutyrate have been suggested. A plausible pathway has been outlined for the terminal oxidation pattern in the Pseudomonad (PL-strain).Abbreviations NAD Nicotinamide adenine dinucleotide - FAD Flavine adenine dinucleotide - -KGA -keto-glutaric acid - CFE cell-free extract - CoA coenzyme A in its reduced state Communication number 1426 from the National Chemical Laboratory.     

The bacterial degradation of flavonoids. Hydroxylation of the A-ring of taxifolin by a soil pseudomonad

Cell-free extracts prepared from a Pseudomonas sp. grown on (+)-catechin oxidized taxifolin in the presence of NAD(P)H and molecular oxygen. The enzyme catalysing the reaction was partially purified and shown to be a flavoprotein. The product was identified as 3',4',5,7,8-pentahydroxyflavanonol (dihydrogossypetin).     

Direct measurement of poly(beta-hydroxybutyrate) in a pseudomonad by solid-state 13C NMR

Four narrow lines are observed in the high-resolution cross-polarization magic-angle spinning 13C NMR spectra of intact, lyophilized samples of Pseudomonas sp. LBr, in addition to the broader lines normally associated with bacterial cellular material. These narrow lines arise from poly(beta-hydroxybutyrate). The cellular carbon contained in this storage material can be measured quantitatively and nondestructively from the solid-state NMR spectra. We find that cells starved for phosphorus store up to 50% of their total carbon as poly(beta-hydroxybutyrate). When such cells are used to inoculate medium containing a source of phosphorus, all of the poly(beta-hydroxybutyrate) is metabolized by the time the culture has reached midlogarithmic growth phase.     

Microbiological transformations of nabilone, a synthetic cannabinoid.

A screening program was conducted to find microorganisms that modify the synthetic cannabinoid nabilone. After purification, the products from three cultures were analyzed by spectral methods to determine their chemical structures. An optically active 9S-hydroxy-6aR,10aR-trans cannabinoid was isolated from a culture of an unidentified soil bacterium designated A24007. From Bacillus cereus cultures were isolated a 9S,6'-dihydroxy-6aR,10aR-trans cannabinoid, a 9S-hydroxy-6'-keto-6aR,10aR-trans cannabinoid, a 9-keto-6'-hydroxy-6aS,10aS-trans cannabinoid, and a 6',9-diketo-6aS,10aS-trans cannabinoid. All of these products were optically active, as was a 9S-hydroxy-6aS,10AS-trans cannabinoid also isolated from B. cereus cultures. A series of acidic products were isolated from cultures of Nocardia salmonicolor. All of these products contained a carboxylic acid group at the terminal end of three-position alkyl side chains having varying numbers of carbon atoms. Two of the acidic products contained a 9-keto group, whereas all other carboxylic acid products were 9-hydroxy cannabinoids. The array of products obtained from incubation of nabilone indicates the usefulness of microbial transformations in the preparation of new cannabinoids.     

Microbiological transformations of delta6a10a-tetrahydrocannabinol.

A screening program was conducted to find microorganisms that catalyze transformation reactions with cannabinoids. Three hundred fifty-eight cultures, consisting of 97 bacteria, 175 actinomycetes, and 86 molds, were incubated in media containing 0.5 mg of Delta(6a,10a)-tetrahydrocannabinol (Delta(6a,10a)-THC) per ml. After 120 h of cultivation, ethyl acetate extracts of the cultures were examined by thin-layer chromatography (TLC) for transformation products. About 18% of the cultures modified Delta(6a,10a)-THC. The ability to modify the substrate did not predominate among any particular group of microorganisms. After purification, the products from three cultures were analyzed by high-resolution mass spectrometry, 100-mHz proton magnetic resonance spectrometry, ultraviolet spectrometry, and infrared spectrometry. These spectral data indicated that a Mycobacterium sp. oxidized Delta(6a,10a)-THC to cannabinol and a diastereomeric pair of 6a-hydroxy-Delta(10,10a)-THC isomers; a Streptomyces sp. and a Bacillus sp. oxidized Delta(6a,10a)-THC to 7-keto-Delta(6a,10a)-THC and 4'-hydroxy-Delta(6a,10a)-THC, respectively. The occurrence of these products and the presence of others that have not yet been isolated or identified indicate that microbial transformation may be a useful tool for the preparation of new cannabinoids that have desirable pharmacological properties.