Prototheca

{{Automatic taxobox

| image = Prototheca wickerhamii.gif

| image_caption = Prototheca wickerhamii, with Gram stain

| taxon = Prototheca

| authority = Krüger, 1894Krüger, W. (1894). Kurze Charakteristik einiger niedrerer Organismen im Saftfluss der Laubbäume. Hedwigia 33: 241-266, [https://www.biodiversitylibrary.org/item/13876#page/300/mode/1up].

| subdivision_ranks = Species

| subdivision_ref = {{cite journal|title=The genus Prototheca (Trebouxiophyceae, Chlorophyta) revisited: Implications from molecular taxonomic studies|vauthors=

Jagielskia T, Bakułaa Z, Gaworb J, Maciszewskic K, Kusberd W, Dyląge M, Nowakowskaf J, Gromadkab R, Karnkowskac A

|journal=Algal Research|year=2019|volume=43|doi=10.1016/j.algal.2019.101639| bibcode=2019AlgRe..4301639J }}

| subdivision =

}}

Prototheca is a genus of algae in the family Chlorellaceae.See the NCBI [https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=3110 webpage on Prototheca]. Data extracted from the {{cite web | url=http://ftp.ncbi.nih.gov/pub/taxonomy/ | title=NCBI taxonomy resources | publisher=National Center for Biotechnology Information | accessdate=2007-03-19}} While this genus is a member of the green algae, all Prototheca no longer have chloroplasts and therefore their photosynthetic ability. Some species can cause protothecosis in humans and various vertebrates.

Etymology

From the Greek proto- (first) + thēkē (sheath), Prototheca is a genus of variably shaped spherical cells of achloric algae in the family Chlorellaceae. Wilhelm Krüger, a German expert in plant physiology and sugar production, reported Prototheca microorganisms in 1894, shortly after spending 7 years in Java studying sugarcane. He isolated Prototheca species from the sap of 3 tree species. Krüger named these organisms as P. moriformis and P. zopfii, the second name as a tribute to Friedrich Wilhelm Zopf, a renowned botanist, mycologist, and lichenologist.{{cite journal |last1=Ollhoff |first1=Rüdiger D. |last2=Sellera |first2=Fábio P. |last3=Pogliani |first3=Fabio C. |date=November 2021 |title= Early Release -Etymologia: Prototheca|journal=Emerg Infect Dis |volume=27 |issue=11 |page=2891 |doi=10.3201/eid2711.211554|quote= Citing public domain text from the CDC. |doi-access=free |pmc=8544978 }}

Biology

Prototheca consists of microscopic, single cells, which may sometimes be clustered to form irregular packets. The cell is generally spherical, ellipsoidal or reniform in shape, with a thin and delicate cell wall. Chloroplasts are absent.{{cite book | title= Gêneros de Algas de Águas Continentais do Brasil: chave para identificação e descrições | edition=2 | year=2006 | first1=Carlos E. M. |last1=Bicudo | first2=Mariângela | last2= Menezes | publisher= RiMa Editora | pages=508 | isbn= 857656064X }}

With the lack of chloroplasts and photosynthetic ability, Prototheca grow heterotrophically and some exhibit parasitism. Other groups of photosynthetic organisms have undergone similar functional losses in photosynthetic ability and shifted to a parasitic lifestyle, such as in apicomplexans.

Evolution and taxonomy

Although Prototheca lack chloroplasts, they were recognized early on as closely related to other Chlorellaceae based on other morphological and physiological traits similar to the group.{{Cite journal |last1=Lass-Flörl |first1=Cornelia |last2=Mayr |first2=Astrid |date=2007-04-01 |title=Human Protothecosis |journal=Clinical Microbiology Reviews |language=en |volume=20 |issue=2 |pages=230–242 |doi=10.1128/CMR.00032-06 |issn=0893-8512 |pmc=1865593 |pmid=17428884}}{{Cite journal |last1=Ueno |first1=Ryohei |last2=Urano |first2=Naoto |last3=Suzuki |first3=Motofumi |date=2003-06-01 |title=Phylogeny of the non-photosynthetic green micro-algal genus Prototheca (Trebouxiophyceae, Chlorophyta) and related taxa inferred from SSU and LSU ribosomal DNA partial sequence data |url=https://academic.oup.com/femsle/article/223/2/275/499272 |journal=FEMS Microbiology Letters |volume=223 |issue=2 |pages=275–280 |doi=10.1016/s0378-1097(03)00394-x |pmid=12829298 |issn=0378-1097}} Phylogenetics confirm that Prototheca species are closely related to Chlorella and other genera, although it is not yet clear whether Prototheca is a monophyletic group.{{Cite journal |last1=Plieger |first1=Tanja |last2=Wolf |first2=Matthias |date=2022-02-01 |title=18S and ITS2 rDNA sequence-structure phylogeny of Prototheca (Chlorophyta, Trebouxiophyceae) |journal=Biologia |language=en |volume=77 |issue=2 |pages=569–582 |doi=10.1007/s11756-021-00971-y |bibcode=2022Biolg..77..569P |issn=1336-9563|doi-access=free }}

Pathogenicity

Some species in the genus Prototheca are known to cause protothecosis, one of the few researched diseases caused by algae, which are categorized as Algaemia. P. wickerhamii is the main causing agent of protothecosis in humans, and was first identified as such in 1964. A strain of P. bovis (formerly classified under P. zopfii) is known to cause this disease in cattle, dogs, buffalo, and horses.{{cite journal|doi=10.1371/journal.ppat.1009362|doi-access=free |title=Now for something completely different: Prototheca, pathogenic algae |date=2021 |last1=Shave |first1=Christopher D. |last2=Millyard |first2=Linda |last3=May |first3=Robin C. |journal=PLOS Pathogens |volume=17 |issue=4 |pages=e1009362 |pmid=33793666 |pmc=8016101 }}

Symptoms include: Cutaneous lesions, Olecranon bursitis.

References

Category:Trebouxiophyceae genera

Category:Chlorellaceae

Category:Plants described in 1894