Pathways of Degradation

Don RH, AJ Wightman, HH Knackmuss, KN Timmis (1985) Transposon mutagenesis and cloning analysis of the pathways of degradation of 2,4-dichlorophenoxyacetic acid and 3-chlorobenzoate in Alcaligenes eutrophus JMP134 (pJP4). J Bacterial 161 85-90. 

Strains may be able to regulate the pathway of degradation of toluene to the availability of oxygen aerobic degradation by dioxygenation and under denitrifying conditions in the absence of oxygen by the benzylsuccinate pathway. 

Combined use of and NMR in a powerful combination to deduce the pathways of degradation of chloroethene (vinyl chloride) (Castro et al. 1992a,b)... 

The simplest alkane is methane, but the pathways for its degradation and assimilation do not reflect this structural simplicity. In outline, the pathway of degradation is straightforward and involves three stages ... 

Firestone MK, JM Tiedje (1978) Pathway of degradation of nitrilotriacetate by a Pseudomonas sp. Appl Environ Microbiol 35 955-961. 

He Z, JC Spain (1997) Studies of the catabolic pathway of degradation of nitrobenzene by Pseudomonas pseudoalcaligenes JS45 removal of the amino group from 2-aminomuconic semialdehyde. Appl Environ Microbiol 63 4839-4843. 

Although sulfate is formed by hydrolysis of both alkyl and aryl sulfates, the pathway of degradation for aryl sulfates is controlled by the source of sulfur (Cook et al. 1999). The complex issues surrounding the hydrolysis of sulfate esters have been discussed (Kertesz 1999), and are illustrated by the number and substrate specificity of alkyl sulfatases for the surfactant 2-butyloctyl sulfate in Pseudomonas sp. strain AE-A (Ellis et al. 2002). 

T. J. Ahern, M. C Manning, eds., Stability of protein pharmaceuticals, Part B. In Vivo Pathways of Degradation and Strategies for Protein Stabilization, Plenum Press, New York, 1992. 

C. Oliyai, R. T. Borchardt, Chemical Pathways of Peptide Degradation. VI. Effect of the Primary Sequence on the Pathways of Degradation of Aspartyl Residues in Model Hexapeptides , Pharm. Res. 1994, 11, 751 -758. 

Arrhenius plots permit the determination of activation energies (Ea) associated with a particular pathway of degradation that allows one to estimate reaction rates as a function of temperature. Such information, if demonstrated to accurately model... 

Rajagopal et al. (1984) used numerous compounds to develop a proposed pathway of degradation of aldicarb in soil. These compounds included aldicarb oxime, A-hydroxymethyl aldicarb, A-hydroxymethyl aldicarb sulfoxide, A-demethyl aldicarb sulfoxide, A-demethyl aldicarb sulfone, aldicarb sulfoxide, aldicarb sulfone, A-hydroxymethyl aldicarb sulfone, aldicarb oxime sulfone, aldicarb sulfone aldehyde, aldicarb sulfone alcohol, aldicarb nitrile sulfone, aldicarb sulfone amide, aldicarb sulfone acid, aldicarb oxime sulfoxide, aldicarb sulfoxide aldehyde, aldicarb sulfoxide alcohol, aldicarb nitrile sulfoxide, aldicarb sulfoxide amide, aldicarb sulfoxide acid, elemental sulfur, carbon dioxide, and water. Mineralization was more rapid in aerobic surface soils than in either aerobic or anaerobic subsurface soils. In surface soils (30 cm depth) under aerobic conditions, half-lives ranged from 20 to 361 d. In subsurface soils (20 and 183 cm depths), half-lives under aerobic and anaerobic conditions were 131-233 and 223-1,130 d, respectively (Ou et al, 1985). The reported half-lives in soil ranged from approximately 70 d (Jury et ah, 1987) to several months (Jones et al, 1986). Bromilow et al. (1980) reported the half-life for aldicarb in soil to be 9.9 d at 15 °C and pH 6.34-7.0. 

Tlie knowledge of the chemical pathways of degradation is also of interest for forecasting die intermediate products, their time evolution, the treatment times, and the eventual toxicity of the effluent, because changing the process conditions could form different species at dissimilar concentrations. This problem would address die environmental compatibility of the process. 

Finally, the chemical pathways of degradation are of fundamental chemical interest because die reaction mechanism proceeds predominantly through radicals in the presence of aqueous systems, a field largely open to investigation. 

Oliyai C, Borchardt RT. Chemical pathways of peptide degradation. VI. Effect of the primary sequence on the pathways of degradation of aspartyl residues in model hexapep-tides. Pharm Res 1994 11(5) 751-758. 

Another enzyme of the mandelate pathway of degradation of aromatic rings (Fig. 25-8) is the cis,cis-muconate lactonizing enzyme which catalyzes the reaction of Eq. 13-23. It has a three-dimensional struc-... 

Threonine is cleaved to acetaldehyde by the same enzyme. A related reaction is indicated in Fig. 24-27 (top). In a more important pathway of degradation of threonine the hydroxyl group of its side chain is dehydrogenated to form 2-amino-3-oxobutyrate which is cleaved by a PLP-dependent enzyme to glycine and acetyl-CoA (Eq. 14-31).214 215... 

The attention of biochemists has been drawn to the importance of pathways of degradation of complex polysaccharides through the existence of at least 35 inherited lysosomal storage diseases 347-351 In many of these diseases one of the 40-odd lysosomal hydrolases is defective or absent. 

Fig. (7). Pathways of degradation of geraniol by Pseudomonas incognita (after [32])...

Numerous bacterial and fungal genera have species able lo degrade hydrocarbons aerobically and the pathways of degradation of representative aliphatic, naphthenic and aromatic, molecules have, been well characterized in at least some species. It is a truism that the hallmark of an oil-degrading organism is its ability to insert oxygen atoms into the hydrocarbon, and... 

Both the decay channels are realized independently. The decay in which the excited quencher Q would be formed is usually largely endoergonic and, therefore, such a pathway of degrading the electronic energy is implausible. 

Pure culture studies are helpful in identifying possible pathways of degradation, but organism(s) isolated by enrichment are not necessarily active in the environment. The organism isolated under high nutrient conditions with the chemical as the only carbon source may not be the organism(s) responsible for the chemical s biodegradation in the environment. 

Montgomery and Freed (1964) reviewed the early research metabolism of triazine herbicides by plants and concluded that there was a good correlation between resistance in plants and the extent of their metabolism. A common pathway of degradation for these chemicals was indicated by the presence of 2-hydroxy analogs. 

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