Wallemia ichthyophaga is one of the three species of fungi in the genus Wallemia, which in turn is the only genus of the class Wallemiomycetes.[1] The phylogenetic origin of the lineage was placed to various parts of Basidiomycota, but according to the analysis of larger datasets it is a (495-million-years-old) sister group of Agaricomycotina.[2][3] Although initially believed to be asexual, population genomics found evidence of recombination between strains and a mating type locus was identified in all sequenced genomes of the species.[3][4]
Wallemia ichthyophaga
Micrograph showing characteristic sarcina-like morphology of W. ichthyophaga and crystals of NaCl.
Only a limited number of strains of W. ichthyophaga have been isolated so far (from hypersaline water of solar salterns, bitterns (magnesium-rich residual solutions in salt production from sea water) and salted meat).[1]
W. ichthyophaga requires at least 1.5 M NaCl for in-vitro growth (or some other osmolyte for an equivalent water activity), and it thrives even in saturated NaCl solution. This makes it the most halophilic fungus known and distinguishes it from halotolerant (e.g. Aureobasidium pullulans) and extremely halotolerant fungi (e.g. Hortaea werneckii), which are able to grow well even in the absence of salt in the medium.[5] Inability to grow without salt is an exception in the fungal kingdom, but is common in halophilic Archaea.[6]
The fungus grows in the form of sarcina-like structures, or compact multicellular clumps.[1] These increase in size almost four-fold when exposed to high salinity, and the cell wall experiences a three-fold thickening. This results in a substantially decreased functional cell volume and is thought to be one of the halotolerance mechanisms of this species.[7]
The whole genome sequencing of W. ichthyophaga revealed that it has one of the smallest of all sequenced basidiomycetous genomes (9.6 Mbp, only 4884 predicted proteins).[3] Contrary to what was observed for the extremely halotolerant H. werneckii, in W. ichthyophaga there are almost no expansions in metal cation transporter genes and their expression is not salt-responsive. On the other hand, there is a vast enrichment of hydrophobins (proteins of cell wall with diverse functions and many biotechnological uses), which contain an unusually high proportion of acidic amino acids.[3] High proportion of acidic amino acids is thought to be an adaptation of proteins to high concentrations of salt.[8] After sequencing the genomes of nearly all known strains of W. ichthyophaga, population genomic analysis showed that the species forms a single recombining population.[4]
Referencesedit
^ abcZalar, P.; Sybren De Hoog, G.; Schroers, H. J.; Frank, J. M.; Gunde-Cimerman, N. (2005). "Taxonomy and phylogeny of the xerophilic genus Wallemia (Wallemiomycetes and Wallemiales, cl. Et ord. Nov.)". Antonie van Leeuwenhoek. 87 (4): 311–328. doi:10.1007/s10482-004-6783-x. PMID 15928984. S2CID 4821447.
^Padamsee, M.; Kumar, T. K. A.; Riley, R.; Binder, M.; Boyd, A.; Calvo, A. M.; Furukawa, K.; Hesse, C.; Hohmann, S.; James, T. Y.; Labutti, K.; Lapidus, A.; Lindquist, E.; Lucas, S.; Miller, K.; Shantappa, S.; Grigoriev, I. V.; Hibbett, D. S.; McLaughlin, D. J.; Spatafora, J. W.; Aime, M. C. (2012). "The genome of the xerotolerant mold Wallemia sebi reveals adaptations to osmotic stress and suggests cryptic sexual reproduction" (PDF). Fungal Genetics and Biology. 49 (3): 217–226. doi:10.1016/j.fgb.2012.01.007. PMID 22326418.
^ abcdZajc, J.; Liu, Y.; Dai, W.; Yang, Z.; Hu, J.; Gostin Ar, C.; Gunde-Cimerman, N. (2013). "Genome and transcriptome sequencing of the halophilic fungus Wallemia ichthyophaga: Haloadaptations present and absent". BMC Genomics. 14: 617. doi:10.1186/1471-2164-14-617. PMC3849046. PMID 24034603.
^Gostinčar, C.; Lenassi, M.; Gunde-Cimerman, N.; Plemenitaš, A. (2011). Fungal Adaptation to Extremely High Salt Concentrations. Advances in Applied Microbiology. Vol. 77. pp. 71–96. doi:10.1016/B978-0-12-387044-5.00003-0. ISBN9780123870445. PMID 22050822.
^Gostinčar, C.; Grube, M.; De Hoog, S.; Zalar, P.; Gunde-Cimerman, N. (2010). "Extremotolerance in fungi: Evolution on the edge". FEMS Microbiology Ecology. 71 (1): 2–11. Bibcode:2010FEMME..71....2G. doi:10.1111/j.1574-6941.2009.00794.x. PMID 19878320.
^Kralj Kuncic, M.; Kogej, T.; Drobne, D.; Gunde-Cimerman, N. (2009). "Morphological Response of the Halophilic Fungal Genus Wallemia to High Salinity". Applied and Environmental Microbiology. 76 (1): 329–337. doi:10.1128/AEM.02318-09. PMC2798636. PMID 19897760.
^Madern, D.; Ebel, C.; Zaccai, G. (2000). "Halophilic adaptation of enzymes". Extremophiles: Life Under Extreme Conditions. 4 (2): 91–98. doi:10.1007/s007920050142. PMID 10805563. S2CID 32590023.
March 21, 2024
wallemia, ichthyophaga, three, species, fungi, genus, wallemia, which, turn, only, genus, class, wallemiomycetes, phylogenetic, origin, lineage, placed, various, parts, basidiomycota, according, analysis, larger, datasets, million, years, sister, group, agaric. Wallemia ichthyophaga is one of the three species of fungi in the genus Wallemia which in turn is the only genus of the class Wallemiomycetes 1 The phylogenetic origin of the lineage was placed to various parts of Basidiomycota but according to the analysis of larger datasets it is a 495 million years old sister group of Agaricomycotina 2 3 Although initially believed to be asexual population genomics found evidence of recombination between strains and a mating type locus was identified in all sequenced genomes of the species 3 4 Wallemia ichthyophagaMicrograph showing characteristic sarcina like morphology of W ichthyophaga and crystals of NaCl Scientific classificationKingdom FungiDivision BasidiomycotaClass WallemiomycetesOrder WallemialesFamily WallemiaceaeGenus WallemiaSpecies W ichthyophagaBinomial nameWallemia ichthyophagaJohan Olsen 1887Only a limited number of strains of W ichthyophagahave been isolated so far from hypersaline water of solar salterns bitterns magnesium rich residual solutions in salt production from sea water and salted meat 1 W ichthyophaga requires at least 1 5 M NaCl for in vitro growth or some other osmolyte for an equivalent water activity and it thrives even in saturated NaCl solution This makes it the most halophilic fungus known and distinguishes it from halotolerant e g Aureobasidium pullulans and extremely halotolerant fungi e g Hortaea werneckii which are able to grow well even in the absence of salt in the medium 5 Inability to grow without salt is an exception in the fungal kingdom but is common in halophilic Archaea 6 The fungus grows in the form of sarcina like structures or compact multicellular clumps 1 These increase in size almost four fold when exposed to high salinity and the cell wall experiences a three fold thickening This results in a substantially decreased functional cell volume and is thought to be one of the halotolerance mechanisms of this species 7 The whole genome sequencing of W ichthyophaga revealed that it has one of the smallest of all sequenced basidiomycetous genomes 9 6 Mbp only 4884 predicted proteins 3 Contrary to what was observed for the extremely halotolerant H werneckii in W ichthyophaga there are almost no expansions in metal cation transporter genes and their expression is not salt responsive On the other hand there is a vast enrichment of hydrophobins proteins of cell wall with diverse functions and many biotechnological uses which contain an unusually high proportion of acidic amino acids 3 High proportion of acidic amino acids is thought to be an adaptation of proteins to high concentrations of salt 8 After sequencing the genomes of nearly all known strains of W ichthyophaga population genomic analysis showed that the species forms a single recombining population 4 References edit a b c Zalar P Sybren De Hoog G Schroers H J Frank J M Gunde Cimerman N 2005 Taxonomy and phylogeny of the xerophilic genus Wallemia Wallemiomycetes and Wallemiales cl Et ord Nov Antonie van Leeuwenhoek 87 4 311 328 doi 10 1007 s10482 004 6783 x PMID 15928984 S2CID 4821447 Padamsee M Kumar T K A Riley R Binder M Boyd A Calvo A M Furukawa K Hesse C Hohmann S James T Y Labutti K Lapidus A Lindquist E Lucas S Miller K Shantappa S Grigoriev I V Hibbett D S McLaughlin D J Spatafora J W Aime M C 2012 The genome of the xerotolerant mold Wallemia sebi reveals adaptations to osmotic stress and suggests cryptic sexual reproduction PDF Fungal Genetics and Biology 49 3 217 226 doi 10 1016 j fgb 2012 01 007 PMID 22326418 a b c d Zajc J Liu Y Dai W Yang Z Hu J Gostin Ar C Gunde Cimerman N 2013 Genome and transcriptome sequencing of the halophilic fungus Wallemia ichthyophaga Haloadaptations present and absent BMC Genomics 14 617 doi 10 1186 1471 2164 14 617 PMC 3849046 PMID 24034603 a b Gostincar Cene Sun Xiaohuan Zajc Janja Fang Chao Hou Yong Luo Yonglun Gunde Cimerman Nina Song Zewei 2019 Population Genomics of an Obligately Halophilic Basidiomycete Wallemia ichthyophaga Frontiers in Microbiology 10 2019 doi 10 3389 fmicb 2019 02019 ISSN 1664 302X PMC 6738226 PMID 31551960 Gostincar C Lenassi M Gunde Cimerman N Plemenitas A 2011 Fungal Adaptation to Extremely High Salt Concentrations Advances in Applied Microbiology Vol 77 pp 71 96 doi 10 1016 B978 0 12 387044 5 00003 0 ISBN 9780123870445 PMID 22050822 Gostincar C Grube M De Hoog S Zalar P Gunde Cimerman N 2010 Extremotolerance in fungi Evolution on the edge FEMS Microbiology Ecology 71 1 2 11 Bibcode 2010FEMME 71 2G doi 10 1111 j 1574 6941 2009 00794 x PMID 19878320 Kralj Kuncic M Kogej T Drobne D Gunde Cimerman N 2009 Morphological Response of the Halophilic Fungal Genus Wallemia to High Salinity Applied and Environmental Microbiology 76 1 329 337 doi 10 1128 AEM 02318 09 PMC 2798636 PMID 19897760 Madern D Ebel C Zaccai G 2000 Halophilic adaptation of enzymes Extremophiles Life Under Extreme Conditions 4 2 91 98 doi 10 1007 s007920050142 PMID 10805563 S2CID 32590023 Retrieved from https en wikipedia org w index php title Wallemia ichthyophaga amp oldid 1194774857, wikipedia, wiki, book, books, library,
