Designation of Phylum Cryptomycota Within Kingdom Fungi

Designation of phylum cryptomycota within dry land country Fungi Introduction The cryptomycota atomic number 18 considered to be to be an early branching clade of organisms, the only cognize members atomic number 18 species that belong in the genus Rozella (Lara et al 2010, Jones et al 2011, pack and Berbee 2012). It has been suggested due mostly to the amount of environmental sequences collected the phylum whitethorn be as divers(prenominal) as the whole kingdom kingdom Fungi (Jones et al 2011).While Rozella were originally located in the fungous phylum Chytridiomycota(Jones and agony 2012), a multi-gene molecular phylogeny of the Chytridiomycota name Rozella was in fact part of a separate linage considered to be the most basal lineage within the fungal kingdom (James et al 2006). Analysis of environmental DNA samples based on the analysis of SSU ribonucleic acid ( meek subunit ribosomal RNA genes)had revealed 26 sequences, previously unknown, which clustered closely to deuce species of Rozella included in the survey (Lara et al 2010).Lara et al tentatively named this clade Rozedilla (Lara et al 2010, Jones et al 2011). However this clade was expanded to include 40 sequences effect in marine and freshwater environments. This clade was renamed cryptomycota to reflect the position of the group relative to the kingdom Fungi and its mostly hidden nature, as a large number of the phylum ar only known from SSU RNA environmental surveys and their similarity in word structure and life-cycle to the Rozella is unknown (Jones et al 2011).Cryptomycota cells from freshwater samples, most notably from the Washington utterer pond (Exeter University, Devon, UK, 50. 7339uN, 3. 5375uW), were visualised with fluorescence in situ hybridization techniques. These target cells were lay downn to be small eukaryotes 3 to 5 ? meters in length (Jones et al 2011). Counter-staining with TAT1 tubulin revealed The target cells undetermined of forming a microtubule based flagellum (see fig 1)(Jones et al 2011). Chitin was not found in whatsoever of the morphs observed, this was tested by co-staining with cell circumvent markers (calcofluor whiten and lectin wheat germ agglutinin).Cellulose was also not present (Jones et al 2011). flesh 1 Micrographs showing flagella on cryptomycota cells, as detected by TAT1 tubulin antibody(Jones et al 2011) This study led Jones et al to the conclusion that the Cryptomycota were an intermediate group in the midst of fungus and protists. Others such as James and Berbee contend that they may have helpless their dinner jacket through convergence. Rather than evolutionary intermediates, the cryptomycota may be strange, divergent fungi (James and Berbee 2012).The term dinner jackets here refers to cell walls. rough such as Griffith, Voight and Kirk would not consider the phylum fungal, but a non fungal opisthkonta exchangeable the Microsporidia(2011). In this essay I intended to explore the inference both for and against the inclusion of the phylum Cryptomycota in the kingdom fungi. To do this it is important to infer the characteristics and life-cycle of Cryptomycota and what makes an organism part of the kingdom fungi. Characteristics of CryptomycotaThe known Cryptomycota Rozella is a genus of entirely bloodsucking species that infect the thalli and sporidia of Chytridiomycota , Blastocladiomycota and some species of Oomycota. Study of Rozella allomycis , the only cultured Rozella species has shown it does ,unlike Fungi, not shape cell walls at any time during there trophic phases like Fungi however they exhibit a zoosporic uniflagilate stage in which they propagate(Jones and Pang 2012) . James and Berbee demonstrated that chitin is present in the inner cell wall of immature spores via calcofluor white staining(2012).Zoospores attach to receptors on the egress of its host ,penetrating its surface with a germ tube in front developing a peeled multinucleate sporangium (Jones and Pan g 2012)It is theorised that the uptake of nutrients is via phagocytosis (Powell 1984), however this is not known to be unfeigned of all Rozella. Zoospores form inside the host before being explosive discharged from exit papillae(Jones and Pang 2012) . Jones et als observation of Cryptomycota cells show a certain similarity to the life-cycle of Rozella.Three life stage cycles were observed (fig 2), a zoosporic uniflagelate morph ,a non-flagellate cyst morph and a parasitic morph where the organism is attached to a host diatom . Jones et al admit, however, that stages in the life-cycle argon probably to have been missed in their study and due to the diversity of the Cryptomycota, the life-cycle is marvelous to represent the entirety of the group (2011). Chitin was not found in any of the stages observed (Jones et al 2011) FIG 2Putative Cryptomycota skeleton life-cycle (Jones et al 2011)Are Cryptomycota fungi? The penguin dictionary of biology defines Fungi as a kingdom of eukaryotic primarilary acellular organisms typically organised into cylindrical hypha . Their nutrition is osmotrophic and never phagotrophic . Hyphal walls are characterised by chitin and ? -glucans (2004). Cryptomycota differs greatly from this standard definition of a fungi by not processing a cell wall ,forming hyphae and is probably to be phagotrophic. There are other organisms that are included in the kingdom fungi that do not fit with these definitions .For example yeasts puke by budding and are not organised into hypha. Zoospores are a shared characteristic with zoosporic true fungi and in most phylogenies constructed Cryptomycota are basal to fungi. Information on the life cycle stages is incomplete , it is practical some examples of cryptomycota process a chitinous cell wall at some stage in their life-cycles (Jones et al 2011). As a parcel is uncertain about the cryptomycota it is hard to include or exclude them from the kingdom fungi and it seems premature to dub them the most basal fungi .As James and Berbee suggest the loss of a chitinous cell wall may be a secondary adaptation to parasitism not indication of a basal fungi (2012). Almost anything could be found and much take to be before they can be defined as true fungi such as observation of cell division and finis whether members of cryptomycota are phagotrophic or not. What is certain that if this phylum is included in the kingdom fungi , the definition for the whole group must change.