Lichtheimia ramosa
{{Short description|Species of fungus}}
{{Speciesbox
| genus = Lichtheimia
| species = ramosa
| authority = (Zopf) Vuill. (1903)
| synonyms =
- Absidia ramosa
- Mycocladus ramosus
}}
Lichtheimia ramosa is a saprotrophic zygomycete, typically found in soil or dead plant material.{{cite journal | vauthors = Alastruey-Izquierdo A, Hoffmann K, de Hoog GS, Rodriguez-Tudela JL, Voigt K, Bibashi E, Walther G | title = Species recognition and clinical relevance of the zygomycetous genus Lichtheimia (syn. Absidia pro parte, Mycocladus) | journal = Journal of Clinical Microbiology | volume = 48 | issue = 6 | pages = 2154–2170 | date = June 2010 | pmid = 20357218 | doi = 10.1128/JCM.01744-09 | pmc = 2884488 }} It is a thermotolerant fungus that has also been known to act as an opportunistic pathogen–infecting both humans and animals.{{cite journal | vauthors = Schwartze VU, Santiago AL, Jacobsen ID, Voigt K | title = The pathogenic potential of the Lichtheimia genus revisited: Lichtheimia brasiliensis is a novel, non-pathogenic species | journal = Mycoses | volume = 57 | pages = 128–131 | date = December 2014 | issue = Suppl 3 | pmid = 25267009 | doi = 10.1111/myc.12230 | s2cid = 2582054 | doi-access = free }}{{cite journal | vauthors = Schwartze VU, Hoffmann K, Nyilasi I, Papp T, Vágvölgyi C, de Hoog S, Voigt K, Jacobsen ID | display-authors = 6 | title = Lichtheimia species exhibit differences in virulence potential | journal = PLOS ONE | volume = 7 | issue = 7 | pages = e40908 | date = 2012-07-20 | pmid = 22911715 | doi = 10.1371/journal.pone.0040908 | pmc = 3401187 | veditors = Spellberg B | doi-access = free }}
Taxonomy
It was previously known as Absidia ramosa,{{cite journal | vauthors = Garcia-Hermoso D, Hoinard D, Gantier JC, Grenouillet F, Dromer F, Dannaoui E | title = Molecular and phenotypic evaluation of Lichtheimia corymbifera (formerly Absidia corymbifera) complex isolates associated with human mucormycosis: rehabilitation of L. ramosa | journal = Journal of Clinical Microbiology | volume = 47 | issue = 12 | pages = 3862–3870 | date = December 2009 | pmid = 19759217 | pmc = 2786664 | doi = 10.1128/JCM.02094-08 }} but has been known by its current name since the Absidia and Lichtheimia genera were differentiated from each other.{{cite journal | vauthors = Hoffmann K, Discher S, Voigt K | title = Revision of the genus Absidia (Mucorales, Zygomycetes) based on physiological, phylogenetic, and morphological characters; thermotolerant Absidia spp. form a coherent group, Mycocladiaceae fam. nov | journal = Mycological Research | volume = 111 | issue = Pt 10 | pages = 1169–1183 | date = October 2007 | pmid = 17997297 | doi = 10.1016/j.mycres.2007.07.002 }} There has also previously been some disagreement in the scientific community over whether L. ramosa and L. corymbifera were distinct species.{{cite journal | vauthors = Nottebrock H, Scholer HJ, Wall M | title = Taxonomy and identification of mucormycosis-causing fungi. I. Synonymity of Absidia ramosa with A. corymbifera | journal = Sabouraudia | volume = 12 | issue = 1 | pages = 64–74 | date = March 1974 | doi = 10.1080/00362177485380091 | pmid = 4838239 }}{{cite journal | vauthors = Ellis JJ, Hesseltine CW | title = Species of Absidia with ovoid sporangiospores. II | journal = Sabouraudia | volume = 5 | issue = 1 | pages = 59–77 | date = June 1966 | doi = 10.1080/00362176785190111 | pmid = 5963263 }} But L. ramosa was recently established as a distinct species based on genome sequence analysis.
Description
Asexual reproduction of L. ramosa is done by use of sporangiospore-producing sporangia. The sporangiospores are smooth, lightly colored, and bear a long ellipsoid shape. The sporangia are pear shaped and often sport branched sporangiophores. Sexual reproduction in L. ramosa is achieved through zygospores. These zygospores have been found to have equatorial rings with suspensors and bear no appendages.
Distribution and habitat
It is saprotrophic, most commonly found within dead plant material or in the soil. As this species is thermotolerant, with an optimal growth temperature of around 37 °C, {{cite journal | vauthors = Alvarez-Zúñiga MT, Santiago-Hernández A, Rodríguez-Mendoza J, Campos JE, Pavón-Orozco P, Trejo-Estrada S, Hidalgo-Lara ME | title = Taxonomic identification of the thermotolerant and fast-growing fungus Lichtheimia ramosa H71D and biochemical characterization of the thermophilic xylanase LrXynA | journal = AMB Express | volume = 7 | issue = 1 | pages = 194 | date = November 2017 | pmid = 29098440 | pmc = 5668220 | doi = 10.1186/s13568-017-0494-y | doi-access = free }} it has now been found in a wide range of habitats around the world–including North America, South America, Central Europe, Africa, and India.
Epidemiology
It is an opportunistic pathogen that has been associated with mucormycosis in both humans and animals. Mucormycosis due to L. ramosa typically only presents in severely immunocompromised patients{{cite journal | vauthors = Rüping MJ, Heinz WJ, Kindo AJ, Rickerts V, Lass-Flörl C, Beisel C, Herbrecht R, Roth Y, Silling G, Ullmann AJ, Borchert K, Egerer G, Maertens J, Maschmeyer G, Simon A, Wattad M, Fischer G, Vehreschild JJ, Cornely OA | display-authors = 6 | title = Forty-one recent cases of invasive zygomycosis from a global clinical registry | journal = The Journal of Antimicrobial Chemotherapy | volume = 65 | issue = 2 | pages = 296–302 | date = February 2010 | pmid = 20008047 | doi = 10.1093/jac/dkp430 | doi-access = free }} with a wide range of infections being described; including rhinal, cutaneous, rhinocerebral, pulmonary, renal, and disseminated infections. However, there have been some cases of infection among immunocompetent patients, due to soil contamination of a traumatic injury.{{cite journal | vauthors = Bibashi E, de Hoog GS, Pavlidis TE, Symeonidis N, Sakantamis A, Walther G | title = Wound infection caused by Lichtheimia ramosa due to a car accident | journal = Medical Mycology Case Reports | volume = 2 | pages = 7–10 | date = December 2012 | pmid = 24432204 | pmc = 3885937 | doi = 10.1016/j.mmcr.2012.12.001 }} Amphotericin B. is the typical course of treatment for an infection by L. ramosa.{{cite journal | vauthors = Alastruey-Izquierdo A, Cuesta I, Walther G, Cuenca-Estrella M, Rodriguez-Tudela JL | title = Antifungal susceptibility profile of human-pathogenic species of Lichtheimia | journal = Antimicrobial Agents and Chemotherapy | volume = 54 | issue = 7 | pages = 3058–3060 | date = July 2010 | pmid = 20421405 | pmc = 2897292 | doi = 10.1128/AAC.01270-09 }} But if not identified and treated quickly enough, the infection can be fatal.{{cite journal | vauthors = Mouronte-Roibás C, Leiro-Fernández V, Botana-Rial M, Ramos-Hernández C, Lago-Preciado G, Fiaño-Valverde C, Fernández-Villar A | title = Lichtheimia ramosa: A Fatal Case of Mucormycosis | journal = Canadian Respiratory Journal | volume = 2016 | pages = 2178218 | date = 2016 | pmid = 27445521 | pmc = 4904553 | doi = 10.1155/2016/2178218 | doi-access = free }}