Identification of the oosporein biosynthesis gene cluster in an entomopathogenic fungus <i>Blackwellomyces cardinalis</i>

Abstract

Entomopathogenic fungi are group of fungi which infect and kill insects. Some of them infect specific host, but others invade a wide variety of insect species (Zhao et al., 2016). For example, Metarhizium acridum (Driver & Milner) J.F. Bisch., Rehner & Humber infects locusts in a specific manner (Bateman et al., 1996), while Beauveria bassiana (Bals.-Criv.) Vuill. can infect more than 200 insect species including Lepidopteran larvae, mosquitoes, and beetles (Clark et al., 1968;Feng et al., 1994;Masuda, 2000). There are some fungal species that are used as pest control agents. They are considered to have the lowest environmental impact and can be used near agricultural fields and conservation areas, satisfying the demand for more environmentally sustainable technologies. On the other hand, the utility of insecticides is being undermined by problems of insecticide resistance, environmental contamination, and risks to human health (Federici et al., 2008;Thomas & Read, 2007).Blackwellomyces cardinalis (G.H. Sung & Spatafora) Spatafora & Luangsa-ard is a member of Cordycipitaceae, described in 2004 in the southern Appalachians and southeastern Japan that hosts small moth larvae (Sung & Spatafora, 2004). Originally known as Cordyceps cardinalis, a new genus, Blackwellomyces, was proposed due to its morphogenetic novelty (Kepler, et al., 2017). Although there have been reports of transformation of Bl. cardinalis strain C033 by introducing foreign genes, there have been no reports of manipulation of specific genes of Bl. cardinalis itself by homologous recombination (Guo et al., 2013). If the genes of Bl. cardinalis itself can be disrupted and examined, it will be easier to understand the molecular mechanism of pathogenicity of this fungus and to improve its function as a microbial control agent (Zhao et al., 2016).It is also known that fungi produce an abundance of low-molecular-weight organic compounds called secondary metabolites (SMs), which are not indispensable for the maintenance of life (Lim et al., 2012). Some of these compounds are harmful to humans, known as mycotoxins, and some are beneficial to humans, such as antibiotics and substances relevant to human health, and

Bioactive Bioxanthracene and Cyclodepsipeptides from the Entomopathogenic Fungus Blackwellomyces roseostromatus BCC56290

“…Among the other genera of the family Cordycipitaceae is the genus Blackwellomyces whose species were reported to infect the larvae of coleopteran and lepidopteran insects in particular B. calendulinus and B. minutus [6][7][8]. To the best of our knowledge, few SMs were reported from the genus Blackwellomyces cardinalis including the antitrypanosomal cyclohexadepsipeptides, cardinalisamides A-C [9], and oosporein, a bibenzoquinone derivative with potent antimicrobial, antifungal and insecticidal activities [10] whose biosynthetic gene cluster was recently described [11].…”