Publications

• Isolation and Characterization of a Cyclohexane-Metabolizing Xanthobacter sp.

  Trower M.K., Buckland R.M., Higgins R., Griffin M.

  An unusual Xanthobacter sp., capable of independent growth on cyclohexane as the sole source of carbon and energy, has been isolated from soil by using classical enrichment techniques. The mean generation time for growth on cyclohexane was 6 h. The microorganism showed a limited ability to utilize ... >> More

  An unusual Xanthobacter sp., capable of independent growth on cyclohexane as the sole source of carbon and energy, has been isolated from soil by using classical enrichment techniques. The mean generation time for growth on cyclohexane was 6 h. The microorganism showed a limited ability to utilize hydrocarbons, with only alicyclic hydrocarbons closely related to cyclohexane supporting growth. Ultrastructural studies indicated the presence of electron-transparent vesicles in the cyclohexane-grown Xanthobacter sp., but the presence of complex intracytoplasmic membranes could not be identified. A soluble inducible enzyme capable of oxidizing cyclohexane was identified in cell extracts. This enzyme had a pH optimum of 6.5, an absolute specificity for NADPH, and a stoichiometric requirement for molecular O(2) which was consistent with the formation of cyclohexanol. The enzyme showed no activity towards straight chain alkanes and only a limited activity towards unsaturated ring compounds. Enzymatic studies with cell extracts have indicated the main route of metabolism of cyclohexane by this Xanthobacter sp. to proceed via cyclohexane --> cyclohexanol --> cyclohexanone --> 1-oxa-2-oxocycloheptane (epsilon-caprolactone) --> 6-hydroxyhexanoate (6-hydroxycaproate) --> --> adipic acid. Alternative routes involving initial double hydroxylation of the cyclohexane ring may operate fortuituously but are unlikely to represent major pathways for the dissimilation of cyclohexane by this microorganism. << Less

  Appl Environ Microbiol 49:1282-1289(1985) [PubMed] [EuropePMC]

• Enzyme reactions involved in anaerobic cyclohexanol metabolism by a denitrifying Pseudomonas species.

  Dangel W., Tschech A., Fuchs G.

  The enzymes involved in the anaerobic degradation of cyclohexanol were searched for in a denitrifying Pseudomonas species which metabolizes this alicyclic compound to CO2 anaerobically. All postulated enzyme activities were demonstrated in vitro with sufficient specific activities. Cyclohexanol de ... >> More

  The enzymes involved in the anaerobic degradation of cyclohexanol were searched for in a denitrifying Pseudomonas species which metabolizes this alicyclic compound to CO2 anaerobically. All postulated enzyme activities were demonstrated in vitro with sufficient specific activities. Cyclohexanol dehydrogenase catalyzes the oxidation of the substrate to cyclohexanone. Cyclohexanone dehydrogenase oxidizes cyclohexanone to 2-cyclohexenone. 2-Cyclohexenone hydratase and 3-hydroxycyclohexanone dehydrogenase convert 2-cyclohexenone via 3-hydroxycyclohexanone into 1,3-cyclohexanedione. Finally, the dione is cleaved by 1,3-cyclohexanedione hydrolase into 5-oxocaproic acid. Some kinetic and regulatory properties of these enzymes were studied. << Less

  Arch Microbiol 152:271-279(1989) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.

• The metabolism of cyclohexanol by Acinetobacter NCIB 9871.

  Donoghue N.A., Trudgill P.W.

  Acinetobacter NCIB 9871 was isolated by elective culture on cyclohexanol and grows with this compound as sole source of carbon. It displays a restricted growth spectrum, being unable to grow on a wide range of alternative alicyclic alcohols and ketones. Cyclohexanol-grown cells oxidize the growth ... >> More

  Acinetobacter NCIB 9871 was isolated by elective culture on cyclohexanol and grows with this compound as sole source of carbon. It displays a restricted growth spectrum, being unable to grow on a wide range of alternative alicyclic alcohols and ketones. Cyclohexanol-grown cells oxidize the growth substrate at a rate of 230 mul of O2/h per mg dry wt with the consumption of 5.65 mumol of O2/mumol substrate. Cyclohexanone is oxidized at a similar rate with the consumption of 4.85 mumol of O2/mumol. 1-Oxa-2-oxocycloheptane and 6-hydroxyhexanoate are both oxidized at the same slow rate of 44 mul of O2/h per mg dry wt and adipate is not oxidized. Studies with cell extracts reveal the presence of inducible dehydrogenases for cyclohexanol, 6-hydroxyhexanoate and 6-oxohexanoate and a monooxygenase, that in conjunction with a lactonase converts cyclohexanone to 6-hydroxyhexanoate. The monooxygenase is therefore presumed to be of the lactone-forming type and the pathway for conversion of cyclohexanol to adipate; cyclohexanol leads to cyclohexanone leads to 1-oxa-2-oxocycloheptane leads to 6-hydroxyhexanoate leads to 6-oxohexanoate leads to adipate; for which key intermediates have been identified chromatographically, is identical with the route for the oxidation of cyclohexanol by Nocardia globerula CL1. << Less

  Eur J Biochem 60:1-7(1975) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.