Frontiers in Biotransformation: Microbial and Plant Cytochromes P-450 - Biochemical Characteristics, Genetic Engineering and Practical Implications v.4

This volume starts with a substantial overview of the occurrence of cytochrome P-450 in bacterial species, considering historical aspects and especially describes the properties, distribution and diversity of bacterial cytochromes P-450. The book underlines our very different levels of knowledge of several bacterial cytochromes P-450, including specific cytalytic activities and spectral evidence on the one hand and detailed data on molecular structure and function of other species on the other. The first chapter describes the hydrocarbon inducible cytochrome P-450 from acinetobacter calcoaceticus. This microganism has been intensively studied in the past as a model for the assimilation of long chain n-alkanes by bacteria. The catalytic activity of yeast cytochrome P-450 exceeds those of mammalian cytochromes P-450 by 2-3 orders of magnitude. Up to now the reasons for this large difference are not known. But detailed knowledge of the alkane hydroxylating cytochrome P-450 as it is summarized in chapter 3 by Muller, Schunck and Kabgel could be useful for solving this question as it is important for the use of cytochromes P-450 in biotechnology.
In chapter 4, Yoshida and Aoyama deal with details of the molecular mechanism of cytochrome P-450 which was isolated and purified from saccharomyces cerevisiae and identified as lanosterol 14x-demethylase. By means of reconstitution experiments, the authors prove that the fungicidal activity of azole antifungal agents originates from its interaction with cytochrome P-450. This form is the only cytochrome P-450 which is widely distributed in eukaryotes with essentially the same function, that is, 14x-demethylation of lanosterol and cholesterol. Therefore, knowledge about the properties of this monoxygenase is not only of practical interest because of its target function for antifungal agents, but it may also be an important object for studying the evolution of cytochrome P-450. The review by Hudnik-Plevnik and Breskvar contains data about cytochrome P-450 in rhizopus nigricans, one of the biotechnologically important micro-organisms.