Xeromyces

{{Short description|Genus of fungi}} {{Speciesbox | genus = Xeromyces | parent_authority = L.R. Fraser 1954 | species = bisporus | authority = L.R. Fraser 1954 | synonyms = * ''Monascus bisporus'' <small>(L.R. Fraser) Arx 1970</small> | synonyms_ref = <ref>Arx (1970), In: Gen. Fungi Sporul. Cult. (Lehr):84</ref> }}

'''''Xeromyces''''' is a monotypic genus of fungus in the family Monascaceae.<ref name="COL">{{cite web |title=Species 2000 & ITIS Catalogue of Life: 2011 Annual Checklist. |veditors=Bisby FA, Roskov YR, Orrell TM, Nicolson D, Paglinawan LE, Bailly N, Kirk PM, Bourgoin T, Baillargeon G, Ouvrard D |date=2011 |publisher=Species 2000: Reading, UK. |url=http://www.catalogueoflife.org/annual-checklist/2011/search/all/key/xeromyces+bisporus/match/1 |access-date=6 October 2017}}</ref><ref>''Species Fungorum''. Kirk P.M., 2010-11-23</ref> Its only species, '''''Xeromyces bisporus''''', was first described by L.R. Fraser in 1954.<ref>L.R. Fraser (1954), In: Proc. Linn. Soc. N.S.W. 78:245</ref> No subspecies are listed in the Catalogue of Life.<ref name="COL"/>

It is a xerophile, being able to germinate at a water activity levels between 0.62 and 0.97,<ref name="Pitt">{{cite journal |vauthors=Pitt JI, ((Christian JMB)) |url=http://aem.asm.org/content/16/12/1853.full.pdf |title=Water relations of xerophilic fungi isolated from prunes |journal=Applied Microbiology |volume=16 |issue=12 |date=1968 |pages=1853–1858}}</ref> lower than any other known organism with the exception of ''Aspergillus penicillioides''.<ref name="Stevenson">{{cite journal |vauthors=Stevenson A, Hamill PG, O'kane CJ, Kminek G, Rummel JD, Voytek MA, Dijksterhuis J, Hallsworth JE |doi=10.1111/1462-2920.13597 |doi-access=free |title=''Aspergillus penicillioides'' differentiation and cell division at 0.585 water activity |date=2017 |journal=Environmental Microbiology |volume=19 |issue=2 |pages=687–697|hdl=20.500.11755/4094446b-493e-4d42-be20-f7318fdf92df |hdl-access=free }}</ref> However, it requires a higher water activity level to produce spores.<ref name="Pitt" /> It is a spoilage microbe in dry foods with high sugar contents, especially chocolate, honey, molasses, dried fruit or tobacco. Isolation of cultures requires media with 50% glucose.<ref name="Pettersson et al. 2011">{{cite journal |vauthors=Pettersson OV, Su-lin LL, Lantz H, Rice T, Dijksterhuis J, Houbraken J, Samson RA, Shnürer J |title=Phylogeny and intraspecific variation of the extreme xerophile, Xeromyces bisporus. |journal=Fungal Biology |date=2011 |volume=115 |issue=11 |pages=1100–1111 |doi=10.1016/j.funbio.2011.06.012 |pmid=22036289}}</ref>

The estimated genome size of ''X. bisporus'' is 24.8 Mb and the fungus lacks the genes normally associated with mycotoxin production.<ref name="Leong 2015">{{cite journal |last1=Leong |first1=Su-lin L. |last2=Lantz |first2=Henrik |last3=Pettersson |first3=Olga V. |last4=Frisvad |first4=Jens C. |last5=Thrane |first5=Ulf |last6=Helpleper |first6=Hermann J. |last7=Dijksterhuls |first7=Jan |last8=Grabherr |first8=Manfred |last9=Pettersson |first9=Mats |last10=Tellgren-Roth |first10=Christian |last11=Schnürer |first11=Johan |year=2015 |title=Genome and physiology of the ascomycete filamentous fungus ''Xeromyces bisporus'', the most xerophilic organism isolated to date |journal=Environmental Microbiology |volume=17 |issue=2 |pages=496–513 |doi=10.1111/1462-2920.12596 |pmid=25142400 |url=http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-249021 |doi-access=free |hdl=20.500.11755/0d27074b-eb76-4e61-9ee2-a4811f311bd5 |hdl-access=free }}</ref>

It has unstalked cleistothecia, and each of its asci has two ascospores. Its simple asexual state consists of one or two round terminal chlamydospores.<ref>{{cite book |last=Jay |first=James M. |title=Modern Food Microbiology |publisher=Aspen Publishers, Inc. |edition=Fifth |date=1998 |location=Gaithersburg, Maryland |pages=31 |isbn=978-0-8342-1230-5}}</ref>

==References== {{Reflist}}

Category:Aspergillaceae Category:Taxa described in 1954