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A total of 39 phenol- and p-cresol-degraders isolated from the river water continuously polluted with phenolic compounds of oil shale leachate were studied. Species identification by BIOLOG GN analysis revealed 21 strains of Pseudomonas fluorescens (4, 8 and 9 of biotypes A, C and G, respectively), 12 of Pseudomonas mendocina, four of Pseudomonas putida biotype A1, one of Pseudomonas corrugata and one of Acinetobacter genospecies 15. Computer-assisted analysis of rep-PCR fingerprints clustered the strains into groups with good concordance with the BIOLOG GN data. Three main catabolic types of degradation of phenol and p-cresol were revealed. Type I, or meta-meta type (15 strains), was characterized by meta cleavage of catechol by catechol 2,3-dioxygenase (C23O) during the growth on phenol and p-cresol. These strains carried C23O genes which gave PCR products with specific xylE-gene primers. Type II, or ortho-ortho type (13 strains), was characterized by the degradation of phenol through ortho fission of catechol by catechol 1,2-dioxygenase (C12O) and p-cresol via ortho cleavage of protocatechuic acid by protocatechuate 3,4-dioxygenase (PC34O). These strains carried phenol monooxygenase gene which gave PCR products with pheA-gene primers. Type III, or meta-ortho type (11 strains), was characterized by the degradation of phenol by C23O and p-cresol via the protocatechuate ortho pathway by the induction of PC34O and this carried C23O genes which gave PCR products with C23O-gene primers, but not with specific xylE-gene primers. In type III strains phenol also induced the p-cresol protocatechuate pathway, as revealed by the induction of p-cresol methylhydroxylase. These results demonstrate multiplicity of catabolic types of degradation of phenol and p-cresol and the existence of characteristic assemblages of species and specific genotypes among the strains isolated from the polluted river water.

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Aims:  To investigate the effect of various single nutrient deficiencies on poly‐β‐hydroxybutyrate (PHB) biosynthesis in a methane‐utilizing mixed culture (dominant species Methylocystis sp. GB 25 DSM 7674). Methods and Results:  Poly‐β‐hydroxybutyrate accumulation experiments were performed in 7 and 70 l bioreactors and initiated by potassium, sulfur or iron deficiency. After 24 h the PHB content reached levels of 33·6%, 32·6% and 10·4% respectively. Interestingly a polymer with an ultra‐high average‐weight molecular weight (Mw) of 3·1 MDa was accumulated under potassium‐limited conditions. When sulfur and iron were lacking Mw were lower by 20·6 and 41·6%. Potassium‐deficiency experiments were furthermore characterized by a maximum specific PHB formation rate 0·08 g g−1residual biomass (R) h−1 and a yield coefficient of 0·45 g PHB g−1 CH4. Conclusions:  Biosynthesis of an ultra‐high Mw PHB in a methane‐utilizing mixed culture can be induced by potassium deficiency. Significance and Impact of the Study:  This study greatly extends the knowledge in the field of bacterial biopolymer formation with gaseous substrates. The special system used here combines the use of methane a low‐cost substrate available from natural and renewable sources with the possibility of employing a mixed‐culture in an open system for the synthesis of a high‐value product.

A methylphenazonium-zeolite-modified enzyme sensor based on a planar, screen-printed, two-electrode arrangement is described for the subnanomolar detection of phenols. Using tyrosinase (EC 1.14.18.1), a novel polyurethane hydrogel was applied for immobilization and stabilization of the enzyme, which forms a self-adhering layer on the active surface of the strip sensor. Performance and characteristics of the sensor were evaluated with regard to response time, detection limit, selectivity, and dependences on temperature and pH as well as operating and storage stabilities. The sensor shows marked sensitivity to eight phenolic compounds usually present in industrial waste waters. The detection limit for phenol was obtained with 0.25 nM. Comparing sensor responses with DIN and EPA standard methods for the chemical analyses of both synthetic and real sample matrices, the results indicate the feasibility of the strip sensor for sensitive determination of phenols in field analysis.Phenolic compounds are important but toxic starting materials in a broad range of chemical manufacturing processes. Especially in coal conversion industry, phenolic residues are considered an acute enviromental problem. Often soil and surface waters of areas around former production and processing plants are contaminated by phenolic compounds with risk to ground water resources. Therefore, screening, monitoring, and control of these pollutants are of great importance.Photometric analyses by DIN and EPA standard methods12 are now commonly used for the determination of phenols. These procedures usually require sample pretreatment by filtration and distillation. Consequently, a simple and fast alternative method for the determination of phenols is desirable. For this purpose, biosensors based on phenol-oxidizing oxygenases appear promising; tyrosinase (EC 1.14.18.1) and as laccase (EC 1.10.3.2) are suitable receptor compounds, although the catalyzed reactions are different.* 123 Basic studies of physicochemical properties and catalyzed pathways of tyrosinase have shown that the tetrameric enzyme, + Umweltforschungszentrum Leipzig-Halle. * Institut ftir Chemo-und Biosensorik. § Bundesforschungsanstalt fur Landwirtschaft. (1) Deutsche Einheitsverfahren zur Wasser-, Abwasser-, und Schlammuntersuchung Band III; Summarische Wirkungs und Stoffkenngrdssen (Gruppe H); DIN 38409-H16; Bestimmung des Phenolindex; VCH: Weinheim, Germany; Jun 1984.(2) Methods for chemical analysis of water and wastes; EPA manual 600/4-79-020, Method 420.1:

Functionalized compounds, which are difficult to produce by classical chemical synthesis, are of special interest as biotechnologically available targets. They represent useful building blocks for subsequent organic syntheses, wherein they can undergo stereoselective or regioselective reactions. "White Biotechnology" (as defined by the European Chemical Industry [ http://www.europabio.org/white_biotech.htm ], as part of a sustainable "Green Chemistry,") supports new applications of chemicals produced via biotechnology. Environmental aspects of this interdisciplinary combination include: Use of renewable feedstock Optimization of biotechnological processes by means of: New "high performance" microorganisms On-line measurement of substrates and products in bioreactors Alternative product isolation, resulting in higher yields, and lower energy demand In this overview we describe biotechnologically produced pyruvic, 2-oxopentaric and 2-oxohexaric acids as promising new building blocks for synthetic chemistry. In the first part, the microbial formation of 2-oxocarboxylic acids (2-OCAs) in general, and optimization of the fermentation steps required to form pyruvic acid, 2-oxoglutaric acid, and 2-oxo-D-gluconic acid are described, highlighting the fundamental advantages in comparison to chemical syntheses. In the second part, a set of chemical formula schemes demonstrate that 2-OCAs are applicable as building blocks in the chemical synthesis of, e.g., hydrophilic triazines, spiro-connected heterocycles, benzotriazines, and pyranoic amino acids. Finally, some perspectives are discussed.