Frisvad Jens C, Andersen Birgitte, Thrane Ulf
Center for Microbial Biotechnology, BioCentrum-DTU, Søltofts Plads, Building 221, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Mycol Res. 2008 Feb;112(Pt 2):231-40. doi: 10.1016/j.mycres.2007.08.018. Epub 2007 Sep 1.
A secondary metabolite is a chemical compound produced by a limited number of fungal species in a genus, an order, or even phylum. A profile of secondary metabolites consists of all the different compounds a fungus can produce on a given substratum and includes toxins, antibiotics and other outward-directed compounds. Chemotaxonomy is traditionally restricted to comprise fatty acids, proteins, carbohydrates, or secondary metabolites, but has sometimes been defined so broadly that it also includes DNA sequences. It is not yet possible to use secondary metabolites in phylogeny, because of the inconsistent distribution throughout the fungal kingdom. However, this is the very quality that makes secondary metabolites so useful in classification and identification. Four groups of organisms are particularly good producers of secondary metabolites: plants, fungi, lichen fungi, and actinomycetes, whereas yeasts, protozoa, and animals are less efficient producers. Therefore, secondary metabolites have mostly been used in plant and fungal taxonomy, whereas chemotaxonomy has been neglected in bacteriology. Lichen chemotaxonomy has been based on few biosynthetic families (chemosyndromes), whereas filamentous fungi have been analysed for a wide array of terpenes, polyketides, non-ribosomal peptides, and combinations of these. Fungal chemotaxonomy based on secondary metabolites has been used successfully in large ascomycete genera such as Alternaria, Aspergillus, Fusarium, Hypoxylon, Penicillium, Stachybotrys, Xylaria and in few basidiomycete genera, but not in Zygomycota and Chytridiomycota.
次生代谢产物是由一个属、一个目甚至一个门中的少数真菌物种产生的化合物。次生代谢产物谱由真菌在给定基质上能够产生的所有不同化合物组成，包括毒素、抗生素和其他外向型化合物。传统上，化学分类学仅限于脂肪酸、蛋白质、碳水化合物或次生代谢产物，但有时定义得非常宽泛，甚至包括DNA序列。由于次生代谢产物在真菌界的分布不一致，因此尚无法将其用于系统发育研究。然而，正是这种特性使得次生代谢产物在分类和鉴定中非常有用。有四类生物是次生代谢产物的特别好的生产者：植物、真菌、地衣真菌和放线菌，而酵母、原生动物和动物则是效率较低的生产者。因此，次生代谢产物主要用于植物和真菌分类学，而化学分类学在细菌学中被忽视。地衣化学分类学基于少数生物合成家族（化学综合征），而丝状真菌则针对多种萜类、聚酮化合物、非核糖体肽及其组合进行了分析。基于次生代谢产物的真菌化学分类学已成功应用于大型子囊菌属，如链格孢属、曲霉属、镰刀菌属、炭团菌属、青霉属、葡萄穗霉属、炭角菌属，但在接合菌门和壶菌门中尚未应用。
