Rhizopus


Rhizopus is a genus of common saprophytic fungi on plants and specialized parasites on animals. They are found in a wide variety of organic substances, including "mature fruits and vegetables", jellies, syrups, leather, bread, peanuts, and tobacco. They are multicellular. Some Rhizopus species are opportunistic human pathogens that often cause fatal disease called mucormycosis. This widespread genus includes at least eight species.
Rhizopus species grow as filamentous, branching hyphae that generally lack cross-walls. They reproduce by forming asexual and sexual spores. In asexual reproduction, spores are produced inside a spherical structure, the sporangium. Sporangia are supported by a large apophysate columella atop a long stalk, the sporangiophore. Sporangiophores arise among distinctive, root-like rhizoids. In sexual reproduction, a dark zygospore is produced at the point where two compatible mycelia fuse. Upon germination, a zygospore produces colonies that are genetically different from either parent.
Various species, including R. stolonifer, may cause soft rot in sweet potatoes and Narcissus.
Rhizopus increases the nutrient content of soils, it does this by degrading certain toxins and inhibiting the growth of Aspergillus flavus, a toxigenic fungus. In addition to that, there is even a type of Rhizopus that has proven to reduce colon carcinogenesis in rats by elevating factors of mucins, immunoglobulin A, and organic acids and give protection to piglets from Escherichia coli-infection by inhibiting adhesion to the intestinal membranes.

Phylogeny

Rhizopus oryzae has heterothallic mating with a + and a - mating type. Rhizopus species have large genomes with evidence of full genome duplication.

Species