P450 BM3 is a natural fusion protein containing a heme catalytic domain fused to a CPR-like domain that binds two flavin cofactors (FAD and FMN). This allows this enzyme to have one of the highest catalytic rates of any P450. Such characteristics make P450 BM3 an attractive enzy…
This thesis is focused on an investigation of the mechanisms of three enzymatically mediated carbon skeleton isomerisation reactions. Chapter 1 provides an overview of some representative examples of the carbon skeleton rearrangement reactions in enzymology. Chapter 2 describes …
Cytochrome P450 (P450) enzymes are found in all kingdoms of life, catalysing a wide range of biosynthetic and metabolic processes. They are, in fact, of particular interest in a variety of applications such as the design of agents for the inhibition of a particular P450 to comba…
Turkey muscle is more prone to lipid oxidation than chicken muscle, which can be partly attributed to decreased accumulations of alpha tocopherol (AT) in muscle of turkeys relative to chickens. Tocopherol metabolites were measured in turkey and chicken bile and the concentration…
Cytochrome P450 enzymes are involved in the metabolism of foreign substances that are present within living organisms. These P450s are classified as Phase I metabolizing enzymes that are found mainly in the liver, they belong to a superfamily of heme containing monoxygenases tha…
Smoking is a major preventable cause of death throughout the world and the need for cessation is unanimously supported by clinicians and scientists. Nicotine in cigarettes is believed to cause tobacco dependence and addiction and low doses of nicotine are found in nicotine repla…
AaeAPO, a novel extracellular heme-thiolate peroxygenase, from the agaric fungus Agrocybe aegerita was recently discovered to catalyze the cytochrome P450-like monooxygenation of diverse organic compounds, using hydrogen peroxide as a cosubstrate. In this dissertation, the funct…
1. Drug resistant strains of P. falciparum are becoming increasingly prevalent in most malaria endemic areas of the world, complicating treatment and prophylaxis. The prevalence of P. falciparum was assessed in six villages in the Punjab, Pakistan. The study was carried out duri…
Cytochrome P450 2D6 (CYP2D6) is the gene that encodes the drug metabolising enzyme (DME) that is responsible for the debrisoquine/sparteine oxidation polymorphism in humans. CYP2D6 has been characterised both genetically and phenotypically in a wide variety of ethnic groups and …
Aflatoxin B1 (AFB1) is a potent dietary hepatocarcinogen and may be a lung carcinogen when inhaled. To study the relative ability of lung and liver to metabolize AFB1, a susceptible (Swiss-Webster rat) and resistant species (Syrian golden hamster) were pretreated with inducing a…
Hydroquinone (HQ) is oxidized and conjugated with glutathione (GSH) to form HQ-GSH metabolites which play a major role in HQ nephrotoxicity. Species differences exist in HQ-GSH-induced nephrotoxicity. Rats and guinea pigs are sensitive while hamsters and mice are resistant to HQ…