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Pseudomonas sp. clone A appears to perform two different initial reductive reactions in the metabolism of 2,4,6-trinitrotoluene. One process eliminates a nitro group from the aromatic ring and allows it to be utilized as an N-source while the other generates side products. Specifically, it uses 2,4,6-trinitrotoluene, 2,4-dinitrotoluene and 2,6-dinitrotoluene as an N-source following the enzymatic removal of nitro groups from the aromatic ring.

The Pseudomonas putida strain DOT-T1, isolated with toluene as the only carbon source, uses toluene-4-monooxygenase as the pathway to grow on toluene, unlike the strain P. putida Idaho which uses the benzyl alcohol pathway. These results indicate that the ability to grow on organic solvents is specific to strains rather than dependent on particular paths. Transfer of the TOL plasmid pWW0-Km results in expansion of the strain's catabolic potential to cover m- and p-xylene and related aromatic solvents.

The isolation and characterization of a bacterium, Pseudomonas sp. strain C1S1, that utilizes 2,4,6-trinitrotoluene (TNT) as an N source, were reported. A derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium was isolated. Transfer of a Pseudomonas putida TOL plasmid to Pseudomonas sp. clone A allowed the transconjugants to use TNT as the sole C and N source. The bacteria that mineralized TNT still had the ability to reduce nitro groups on the aromatic rings and accumulated azoxy dimers.

The gram-negative and oxidase-negative Klebsiella oxytoca isolate 15 exhibited high tolerance to high nitrate concentrations. Klebsiella oxytoca isolate 15 cells grown on enrichment cultures with high nitrate content exhibited unaltered phospholipid patterns compared to other bacteria during prolonged incubations. However, the growth patterns of the gram-negative bacterium was altered by nitrate in a concentration-dependent manner.

A stable 4-nitrotoluene degrader strain named Pseudomonas fluorescence strain 410PR was constructed based on the introduction of the PWW0 plasmid via conjugation with Pseudomonas putida. The novel 4-nitrotoluene degrader strain was produced by combining the ability of Pseudomonas fluorescens 410P to degrade 4-nitrobenzoate and the TOL pWWO upper pathway for oxidation of 4-nitrotoluene. Furthermore, the bioengineered Pseudomonas fluorescence 410PR exhibited stable 4-nitrotoluene degrading characteristics in the absence of selective pressure.

Introduction: L‐Dopa, a key neurotransmitter used to treat neural disorders such as Parkinson's disease, is found in the seeds of the genus Mucuna at a sufficient concentration for possible commercial use. Objective: To develop a simple and reliable method to extract L‐Dopa from M. pruriens seeds in an aqueous medium and then quantitate this compound using a 1H qNMR method (internal standard); and also to evaluate the accuracy and reproducibility of this method with an NMR calibration curve. Methodology: The extraction method of L‐Dopa from M. pruriens was optimized. The quantitation with single point quantitative NMR (qNMR) and NMR calibration curve was based on the resonance properties of the main functional groups of the L‐Dopa molecule, in particular the signals of the three aromatic protons, which were compared with the signal of an internal standard such as syringic acid. The accuracy (precision and trueness) and reproducibility of both NMR techniques were evaluated. Results: The methods of single point qNMR and NMR calibration curve, applied to the seeds of two M. pruriens varieties, gave very similar L‐Dopa contents: 3.0–3.2% and 3.0–3.1%, respectively. Conclusion: The statistical analysis confirmed the accuracy and reproducibility of this single point qNMR method (internal standard) for determining L‐Dopa, as well as other commercial preparations of this species, without performing an NMR calibration curve. The L‐Dopa content was determined in Mucuna pruriens seeds by means of a qNMR method, also optimizing the extraction process. The accuracy (precision and trueness) and the reproducibility of this NMR technique were evaluated. The results showed a content of L‐Dopa in Mucuna pruriens seeds of approximately 3.0−3.2%, similar to the percentages published for other methods of quantitation of this compound. [ABSTRACT FROM AUTHOR]

A quasi-defined medium has been developed to support Streptococcus agalactiae growth as a pigmented colony. The medium is made up of salts, starch, a peptic digest of albumin, nucleosides, amino acids and vitamins.

The first route towards taiwaniaquinoid terpenes bearing an A/B trans-configuration has been developed through a sequence which includes a thermal 6p electrocyclization. [ABSTRACT FROM AUTHOR]

Aromatic carboxylic acids substituted with methoxylated groups are among the most abundant products in 'alpechin', the wastes resulting from pressing olives to obtain olive oil. Degradation of o-methoxybenzoate by an stable consortium made of a gram positive bacterium, Arthrobacter oxydans, and gram negative one, Pantotea agglomerans, was shown to mineralize this compound efficiently. he concerted action of both microorganisms was needed for the two first steps n the process, namely, the conversion of o-methoxybenzoate into salycilate, and the hydroxylation of the latter to gentisate. Gentisate was further degraded by the Arthrobacter strain. [ABSTRACT FROM AUTHOR]