The microorganism strains studied were from both Streptomyces bacteria and filamentary fungi, providing a broad overviews for understanding the biosynthesis of natural products in microorganisms. The book also includes reviews for secondary products, antibiotics and various types of natural product biosynthetic pathways. The book describes in detail useful techniques in modern natural product studies, including cloning and knock-out of biosynthetic genes, expression and purification of biosynthetic enzymes, extraction and analysis of chemical compounds. The book introduces the cloning of natural product biosynthetic genes responsible for biosynthesis of griseusin, fusarin C and trichothecene! These compounds are related to three main types of natural products-polyketides, non-ribosomal peptides and terpenes.