Alkane hydroxylases

Some of the major enzyme groups that facilitate this transformation are heme-containing MOs of the cytochrome P450 type [111], alkane hydroxylases, xylene monooxygenases, styrene monooxygenases [105], and haloperoxidases [112],... 

The alkane hydroxylase from Pseudomonas oleovorans is particularly suitable for the epoxidation of terminal aliphatic double bonds and enables rapid access to the (3-blocker metoprolol (Scheme 9.14) [113,116]. Complementing this regioselectivity, chloroperoxidases are particularly suitable biocatalysts for the epoxidation of (ds substituted) subterminal olefins [112,117]. This enzyme also accepts terminal olefins and is utilized for the effident synthesis of P-mevalono-ladone [118]. 

The alkane hydroxylase belongs to a family of nonheme iron oxygenases. There is some structural similarity between the nucleotide sequence of the integral membrane alkane hydroxylase and... 

Ratajczak A, W Geipdorfer, W Hillen (1998) Alkane hydroxylase from Acinetobacter sp. strain ADPl is encoded by alkM and belongs to a new family of bacterial integral-membrane hydrocarbon hydroxylases. A /Environ Mcrofcio/ 64 1175-1179. 

Smits THM, SB Balada, B Witholt, JB van Beilen (2002) Eunctional analysis of alkane hydroxylases from Gram-negative and Gram-positive bacteria. J Bacterial 184 1733-1742. 

The alkane hydroxylase belongs to a family of nonheme iron oxygenases. There is some structural similarity between the nucleotide sequence of the integral-membrane alkane hydroxylase and the subunits of the monooxygenase encoded by xylA and xylM in the TOL plasmid that are involved in hydrox-ylation of the methyl groups in toluene and xylene in Pseudomonas putida PaWl (Suzuki et al. 1991). 

The operation of cytochrome P450 in alkane oxidation has been reported both in bacteria and in yeasts. It has been shown that alkane hydroxylases of CHYP 153 are widespread both in Gram-negative and Gram-positive bacteria that lack the integral membrane alkane hydroxylase (van Beilin et al. 2006). 

Smith CA, MR Flyman (2004) Oxidation of methyl tcrt-butyl ether by alkane hydroxylase in dicyclopro-pyUcetone-induced and n-octane-grown Pseudomonas putida Gpol. Appl Environ Microbiol 70 4544-4550. 

ATP GTP DEPLETION ALKANE HYDROXYLASE 1-Alkenylglycerophosphocholine acyltrans-ferase,... 

ACYL-CoA DESATURASE ALKANE HYDROXYLASE AMINE OXIDASES... 

In other bacteria, such as Acinetobacter, alkane oxidation genes are chromosomal (Singer Finnerty, 1984b). Moreover, some of the genes that participate in alkane oxidation probably comprise indispensable constituents of the bacterial cell. For example, in P. oleovorans, one of the gene products that catalyzes the initial oxidation of aliphatic substrates, the alkane hydroxylase, is an integral cytoplasmic membrane protein, and constitutes after induction 1.5-2% of the total cell protein (Nieboer et al. 1993). 

Nieboer, M., Kingma, J. Witholt, B. (1993). The alkane oxidation system of Pseudomonas oleovorans induction of the alk genes in Escherichia colt W3110 (pGEc47) affects membrane biogenesis and results in overexpression of alkane hydroxylase in a distant cytoplasmic membrane subfraction. Molecular Microbiology, 8, 1039-51. 

Nieder, M. Shapiro, J. (1975). Physiological function of Pseudomonas putida PpG6 (Pseudomonas oleovarans) alkane hydroxylase monoterminal oxidation of alkanes and fatty acids. Journal of Bacteriology, 122, 93-8. 

Shanklin J., Whittle E. and Fox B. G. (1994) Eight histidine residues are catalytically essential in a membrane associated iron enzyme, stearoyl-CoA desaturase and are conserved in alkane hydroxylase and xylene monooxygenase. Biochem. 33, 12787-12794. 

Such transformations can also use 1-hydroxy-1/7-ben-zotriazole in place of the benzothiazoline.159 An alkane hydroxylase has been used to convert alkanes to alcohols.160 Cholesterol can be oxidized to the ketone, cholestenone, with cholesterol oxidase in reversed micelles of water in isooctane in 100% conversion.161... 

The possible involvement of an alkane hydroxylase was recently shown in MTBE oxidation by Methylibium petroleiphilum PMl [30] and in TBA oxidation by Mycobacterium austroafricanum lEP 2012 able to grow on... 

MTBE [39]. The involvement of the alkane hydroxylase in MTBE oxidation... 

Glieder, A., E.T. Farinas, and F.H. Arnold (2002). Laboratory evolution of a soluble, self-sufficient, highly active alkane hydroxylase. Nat. Biotechnol. 20, 1135-1139. 

In contrast to the large amount of the three-dimensional structural data available in the literature, little is known about the physiological fimction of Rd. Typically, Rds exhibit redox potentials in the range of —60 to OmV [24], and are commonly assmned to be involved in electron transfer processes. It has bear demonstrated that Rd can replace ferredoxin as an electron carrier in certain electron transfer reactions [3]. Furthermore, Rd from the aerobe P. oleovorans was proposed to participate in the ctj-hydroxylation of fatty acids and hydrocarbons by transferring electrons to an alkane hydroxylase [7, 25]. Rd isolated from D. gigas was also shown to be involved in the formation of ATP from the degradation of polyglucose in the presence of... 

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