Alkane metabolism

Callaghan AV, LM Gieg, KG Kropp, JM Suflita, LY Young (2006) Comparison of mechanisms of alkane metabolism under sulfate-reducing conditions among two bacterial isolates and a bacterial consortium. Appl Environ Microbiol 72 4274-4282. 

Cravo-Laureau C, V Grossi, D Raphel, R Matherton, A Hirschler-Rea (2005) Anaerobic -alkane metabolism by a sulfate-reducing bacterium Desulfatibacillum aliphaticivorans strain CV2803. Appl Environ Microbiol 71 3458-3467. 

Davidova lA, LM Gieg, M Nanny, KG Kropp, JM Suflita (2005) Stable isotopic studies on -alkane metabolism by a sulfate-reducing bacterial enrichment culture. Appl Environ Microbiol. 71 8174-8182. 

Many bacteria are able grow on medium chain-length alkanes. Of these strains, only P. oleovorans TF4-1L (GPol) has been studied in detail with respect to both the genetics and enzymology of alkane metabolism (Fig. 1) (1), also because this strain has proven to be a versatile biocatalyst (2, and references therein). 

Previously, we have screened the literature for relevant biochemical studies on enzyme systems that oxidize medium chain-length alkanes (1). The Pseudomonas strains mentioned in this paper have been studied in varying detail with respect to the enzymology of medium chain-length alkane metabolism. The alkane hydroxylase systems in these strains show a number of differences, such as the apparent absence of rubredoxin in P. aeruginosa 196 Aa (12). On the whole, however, they resemble each other, and the system of P. oleovorans GPol. As an example, we found that the described substrate range of the paraffin hydroxylase of... 

Huang FC, Peter A, Schwab W (2014) Expression and characterization of CYP52 genes involved in the biosynthesis of sophorolipid and alkane metabolism from Starmerella bombicola. Appl Environ Microbiol 80 766-776... 

Yin H, Anders MW, Korzekwa KR, Higgins L, Thummel KE, Kharasch ED, et al. Designing safer chemicals predicting the rates of metabolism of halogenated alkanes. Proc Natl Acad Sci USA 1995 92 11076-80. 

Aeckersberg F, FA Rainey, F Widdel (1998) Growth, natural relationships, cellular fatty acids and metabolic adaptation of sulfate-reducing bacteria that utilize long-chain alkanes under anoxic conditions. Arch Microbiol 170 361-369. 

The fumarate pathway for the metabolism of alkanes under sulfate-reducing conditions was examined using fully deuterated hexadecane (Callaghan et al. 2006). Identification of the metabolites including labeled methylpentadecylsuccinate and 4-methyloctadecanoate... 

McKenna EJ, RE Kallio (1971) Microbial metabolism of the isoprenoid alkane pristane. Proc Natl Acad Sci USA 68 1552-1554. 

Pirnik MP, RM Atlas, R Bartha (1974) Hydrocarbon metabolism by Brevibacterium erythrogenes normal and branched alkanes. J Bacterial 119 868-878. 

Rabus R, H Wilkes, A Behrends, A Armstroff, T Fischer, AJ Pierik, F Widdel (2001) Anaerobic initial reaction of -alkanes in a denitrifying bacterium evidence for (1-methylpentyl) succinate as initial product and for involvement of an organic radical in -hexane metabolism. J Bacteriol 183 1707-1715. 

Reviews on the microbial metabolism of hydrocarbons with biochemical aspects are available, and inclnde those of Britton (1984) on alkanes, and of Morgan and Watkinson (1994) that also includes cycloalkanes and some aromatic compounds. Virtually all the issues that are discussed in these recur in the examples that are used as illustration. Some broad generalizations are summarized ... 

Further work at EniTecnologies was conducted with Rhodococcus strains. Rhodococ-cus was selected for its metabolical versatility, easy availability in soils and water, and remarkable solvent tolerance. Its capabilities for catalyzing diverse transformation reactions of crude oils, such as sulfur removal, alkanes and aromatics oxidation and catabolism caught their attention. Hence, genetic tools for the engineering of Rhodococcus strains have been applied to improve its biotransformation performance and its tolerance to certain common contaminants of the crude oil, such as cadmium. The development of active biomolecules led to the isolation and characterization of plasmid vectors and promoters. Strains have been constructed in which the careful over-expression of selected components of the desulfurization pathway leads to the enhancement of the sulfur removal activity in model systems. Rhodococcus, Gordona, and Nocardia were transformed in this way trying to improve their catalytic performance in BDS. In a... 

The answer is d. (Hardman, pp 308-313.) Halothane is a substituted alkane general anesthetic. It undergoes significant metabolism in humans with about 20% of the absorbed dose recovered as metabolites. Halothane can cause postoperative jaundice and hepatic necrosis with repeated administration in rare instances. 

Nastainczyk W, Ahr HJ, Ullrich V. 1982b. The reductive metabolism of halogenated alkanes by liver microsomal cytochrome P450. Biochem Pharmacol 31 391-396. 

Miller, R. M. and Bartha, R. (1989). Evidence from liposome encapsulation for transport-limited microbial metabolism of solid alkanes, Appl. Environ. Microbiol., 55, 269-274. 

Perry, J. T., 1984, Microbial Metabolism of Cyclic Alkanes In Petroleum Microbiology (edited by R. M. Atlas), MacMillan Publishing Co., New York, pp. 61-98. 

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