History
Trisporic acid was discovered in 1964 as a metabolite that caused enhanced carotene production in ''Functions in Mucorales
Recognition of compatible sexual partners in zygomycota is based on a cooperative biosynthesis pathway of trisporic acid. Early trisporoid derivatives and trisporic acid induce swelling of two potential hyphae, hence called zygophores, and a chemical gradient of these inducer molecules results in a growth towards each other. These progametangia come in contact with each other and build a strong connection. In the next stage, septae are established to limit the developing zygospore from the vegetative mycelium and in this way the zygophores become suspensor hyphae and gametangia are formed. After dissolving of the fusion wall, cytoplasm and a high number of nuclei from both gametangia are mixed. A selectional process (unstudied) results in a reduction of nuclei and meiosis takes place (also unstudied until today). Several cell wall modifications, as well as incorporation of sporopollenin (dark colour of spores) take place resulting in a mature zygospore. Triporic acid, as the endpoint of this recognition pathway, can solely be produced in presence of both compatible partners, which enzymatically produce trisporoid precursors to be further utilized by the potential sexual partner. Species specificity of these reactions is among others obtained by spatial segregation, physicochemical features of derivatives (volatility and light sensitivity), chemical modifications of trisporoids and transcriptional/posttranscriptional regulation.Biosynthesis
Parasexualism
Trisporoids are also used in the mediation of the recognition between parasite and host. An example is the host-parasite interaction of a parasexual nature observed between ''Parasitella parasitica'', a facultative mycoparasite of zygomycetes, and ''Absidia glauca''. This interaction is an example for biotrophic fusion parasitism, because genetic information is transferred into the host. Many morphological similarities in comparison to zygospore formation are seen, but the mature spore is called a sikyospore and is parasitic. During this process, gall-like structures are produced by the host ''Absidia glauca''. This coupled with further evidence has led to the assumption that trisporiods are not strictly species specific and that trisporiods represent the general principle of mating recognition in Mucorales.References
{{reflist, 35em Carotenoids Carboxylic acids