Generally, fungi are considered as the most common microbes encountered by mammalian hosts due to its ubiquity in nature. Among the fungi, the Zygomycetes represent the most basal terrestrial lineage which can cause infections in humans. They comprise two orders, the Mucorales and the Entomophthorales, which contain human pathogenic species. Members of the Mucorales are responsible GDC 0449 for mucormycosis; the second most common mould fungi infection in the world and infection with members of the Entomophthorales can result in basidiobolomycosis

and conidiobolomycosis. However, the infection does not occur frequently as we have efficient barriers from immune system against the fungal invasion. In this review, a summary is provided on the current literature available on innate immune cells such as polymorphonuclear leucocytes, macrophages, etc. and their interaction with zygomycetes. Zygomycetes are saprobic fungi found ubiquitously in nature. The Zygomycetes is one of the two classes of the phylum Zygomycota, which is traditionally known Selleckchem INK-128 as the most basal terrestrial phylum of the fungal kingdom. The Zygomycetes differs from the Trichomycetes, the second class of the Zygomycota, by the ecological niches they inhabit. Whilst Zygomycetes

mainly occur as saprobionts in soil or parasites and pathogens of plants, animals or other fungi, the Trichomycetes encompass phylogenetically diverse and unrelated groups of heterotrophic microorganisms which are united based on their ecological

habitat and life style. They are typically endocommensals, particularly found in the digestive tract of the aquatic larvae of a number of insects or other arthropod host groups, including crustaceans and diplopods. During extensive phylogenetic studies, the Zygomycota was eliminated as a coherent phylum because molecular phylogenetic analyses revealed its dispersal into five subphyla (Fig. 1a) which comprise a total of 1148 species distributed over nine orders (Fig. 1b).[1-4] All members of the five subphyla have the ability or the potential to produce zygospores during conjugation of two yoke-shaped gametangia. Because the phylogenetic relationship between these subphyla and their orders is not well-understood so far but share morphological features, the term however ‘zygomycetes’ is used in a colloquial sense meaning that it is treated as a coherent group of zygospore-forming fungi. Out of a total of nine orders of the zygomycetes, two, the Mucorales and the Entomophthorales, contain human pathogenic species (Fig. 2).[4] The order Mucorales encompasses various genera, which are potentially human pathogenic. These are Rhizopus, Lichtheimia, Mucor, Rhizomucor, Apophysomyces, Saksenaea, Syncephalastrum and Cunninghamella (Fig. 2).[5] They are saprobic fungi with characteristic morphology of columella which rejuvenates in a funnel-like manner into the apophysis giving the sporangium the appearance of a pear shape (piriform).