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A strategy for elucidating sequence determinants of function in the class of cytochrome P450 (CYP) enzymes that catalyze the first steps of terpene metabolism in wild microbiomes is described. Wild organisms that can use camphor, terpineol, pinene and limonene were isolated from soils rich in coniferous waste. Cell free extracts and growth beers were analyzed by gas chromatography/mass spectrometry to identify primary oxidative metabolites. For one organism, Pseudomonas nitroreducens TPJM, a cytochrome P450 (CYP108B1) isolated from cell free extracts was demonstrated to catalyze the oxidation of α-terpineol in assays combining the native ferredoxin and putidaredoxin reductase, and the resulting oxidation products identified by gas chromatography/mass spectrometry. Shotgun sequencing of PnTPJM identified four candidate P450 genes, including an apparently fragmentary gene with a high degree of homology with the known enzyme CYP108 (P450 terp )., (Copyright © 2018. Published by Elsevier Inc.)

The existence of a substrate-sensitive equilibrium between high spin (S=5/2) and low spin (S=1/2) ferric iron is a well-established phenomenon in the cytochrome P450 (CYP) superfamily, although its origins are still a subject of discussion. A series of mutations that strongly perturb the spin state equilibrium in the camphor hydroxylase CYP101A1 were recently described (Colthart et al., Sci. Rep. 6, 22035 (2016)). Wild type CYP101A1 as well as some CYP101A1 mutants are herein shown to be capable of catalyzing the reduction of nitroacetophenones by NADH to the corresponding anilino compounds (nitroreductase or NRase activity). The distinguishing characteristic between those mutants that catalyze the reduction and those that cannot appears to be the extent to which residual high spin form exists in the absence of the native substrate d-camphor, with those showing the largest spin state shifts upon camphor binding also exhibiting NRase activity. Optical and EPR spectroscopy was used to further examine these phenomena. These results suggest that reduction of nitroaromatics may provide a useful probe of residual high spin states in the CYP superfamily. This article is part of a Special Issue entitled: Cytochrome P450 biodiversity and biotechnology, edited by Erika Plettner, Gianfranco Gilardi, Luet Wong, Vlada Urlacher, Jared Goldstone., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Abstract This is Chapter Thirteen of Leaving Liza, a novel about life, death, love, friendship, jealousy and lesbian ex-lovers. In the novel, six women are spending the weekend at a beach house in Long Island's Hamptons, where they have gathered to be with their friend Liza, who is battling terminal ovarian cancer. Liza's lover, Jill, has agreed to the house party and helped plan the guest list. But, as she smolders with resentment at the attention Liza is getting and the depth of the women's friendships, she begins to come unraveled. After a severe asthma attack that requires an emergency room visit the day before, Jill conducts a seance, purporting to have contacted another of Liza's ex-lovers, who died a few months earlier. Now, on this last night of the house party, she lets Liza and her friends know what she's really feeling. The editors have asked me to add some "commentary" on the questions this story raises about the roles of ex-lovers. I would hope the scene reflects some of the tensions that can occur when ex-lovers choose to remain friends, particularly when those bonds provoke profound jealousy in both current and ex-lovers. For many of us, the job of assuaging and reassuring the current lover while maintaining intimate friendships with an ex-lover is simply too exhausting and prickly to endure. For others, it is worth the struggle. Liza and her friends clearly think it is. But at what point, they all wonder at this house party, does their hunger for honesty and their anger at being insulted and manipulated become more important than keeping the peace, and possibly their friendship with Liza? Perhaps only Liza's death will free them from this compromising coexistence.