Enzymes and genes involved in aerobic alkane degradation

Abstract

Alkanes are major constituents of crude oil. They are also present at low concentrations in diverse non-contaminated because many living organisms produce them as chemo-attractants or as protecting agents against water loss. Alkane degradation is a widespread phenomenon in nature. The numerous microorganisms, both prokaryotic and eukaryotic, capable of utilizing alkanes as a carbon and energy source, have been isolated and characterized. This review summarizes the current knowledge of how bacteria metabolize alkanes aerobically, with a particular emphasis on the oxidation of long-chain alkanes, including factors that are responsible for chemotaxis to alkanes, transport across cell membrane of alkanes, the regulation of alkane degradation gene and initial oxidation.

Responses of Microbial Communities to Hydrocarbon Exposures

“…The aerobic degradation of alkanes, particularly n-alkanes, is well documented (Wang and Shao, 2013;Figure 2a). Alkanes are distributed ubiquitously, and a number of mechanisms activate them by breaking strong C-H bonds, an energetically demanding process.…”

Regulation of the Alkane Hydroxylase CYP153 Gene in a Gram-Positive Alkane-Degrading Bacterium, Dietzia sp. Strain DQ12-45-1b

“…AlkS, a member of the LuxR family regulators, and members of the TetR family repressors were reported to be regulators of AlkB-type AHs (4,12,26). In strains expressing two or more AHs, the AHs are differentially regulated.…”

“…For aerobic alkane degradation, alkane hydroxylases (AHs) are considered to be the essential rate-limiting enzymes (4). Depending on the chain lengths of n-alkanes, we divide the AHs into three categories: methane monooxygenase-like enzymes are responsible for C 1 to C 4 n-alkane hydroxylation, which includes soluble di-iron monooxygenase (SDIMO) (5,6) and membrane-bound particulate copper enzyme (CuMMO) (6,7); the integral membrane nonheme iron AlkB-related monooxygenase (8) and cytochrome P450 enzyme, belonging to the CYP153 family (CYP153) (9), mainly catalyze the hydroxylation of medium-and long-chain alkanes (C 5 to C 16 ); longer alkanes (C 17 plus) are oxidized by the monooxygenases LadA (10) and AlmA (11).…”

Bioprospecting for Genes Encoding Hydrocarbon-Degrading Enzymes from Metagenomic Samples Isolated from Northern Adriatic Sea Sediments

“…AlkB. Long chain length (> C18) n-alkanes are hydroxylated by unrelated enzymes including AlmA and LadA (3). Anaerobic biodegradation of hydrocarbons also occurs, with the most widely reported mechanism for activation of the substrate being enzymatic addition of the hydrocarbon across the double bond of fumarate.…”

“…The published version will differ from this one as a result of linguistic and technical corrections and layout editing. 3 xylene and 2-methylnaphthylsuccinate synthase (Nms) activates 2-methylnaphthalene (4)(5).…”