''BY1'' is a taxonomically unidentified

basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basid ...

fungus A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

. ITS sequencing has placed it in the

Russulales The Russulales are an order of the Agaricomycetes, (which include the agaric genera '' Russula'' and ''Lactarius'' and their polyporoid and corticioid relatives). According to the ''Dictionary of the Fungi'' (10th edition, 2008), the order con ...

and is referred to as a stereaceous basidiomycete. Chemotaxonomically supporting its placement in this group, it produces fomannoxins and vibralactones. The fungus'

mycelia Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are fo ...

were isolated from dead

aspen Aspen is a common name for certain tree species in the Populus sect. Populus, of the ''Populus'' (poplar) genus. Species These species are called aspens: * ''Populus adenopoda'' – Chinese aspen (China, south of ''P. tremula'') * ''Populus da ...

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

, USA. It is presumed to decompose wood by

white rot A wood-decay or xylophagous fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as ''Serpula lacrymans'', and some, such as '' Armillaria'' (honey fungus), are par ...

. The mycelium can be grown on YMG agar at room temperature (4 g/L d-glucose, 4 g/L yeast extract, 10 g/L malt extract, 18 g/L agar). The culture can be obtained at the

Jena Microbial Resource Collection The Jena Microbial Resource Collection (JMRC) is a joint collection of the Leibniz Institute for Natural Product Research and Infection Biology – Hans-Knöll-Institute and the University of Jena. It was founded in October 2010 by merging two earli ...

registration number SF:011241. When the mycelia is wounded by

scalpel A scalpel or bistoury is a small and extremely sharp bladed instrument used for surgery, anatomical dissection, podiatry and various handicrafts. A lancet is a double-edged scalpel. Scalpel blades are usually made of hardened and tempered ...

damage, a yellow pigment appears. These pigments were identified as

polyene In organic chemistry, polyenes are polyunsaturated organic compounds that contain multiple carbon–carbon double bonds (). Some sources consider dienes to be polyenes, whereas others require polyenes to contain at least three carbon–carbon d ...

s by characteristic UV-Vis spectra. The structures of the polyenes were determined by

NMR Nuclear magnetic resonance (NMR) is a physical phenomenon in which atomic nucleus, nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near and far field, near field) and respond by producing ...

. They were identified as 1) (3Z,5E,7E,9E,11E,13Z,15E,17E)-18-methyl-19-oxoicosa-3,5,7,9,11,13,15,17-octaenoic acid; and 2) (3E,5Z,7E,9E,11E,13E,15Z,17E,19E)-20-methyl-21-oxodocosa-3,5,7,9,11,13,15,17,19-nonaenoic acid. The shorter polyene was found to be highly toxic against ''

Drosophila melanogaster ''Drosophila melanogaster'' is a species of fly (an insect of the Order (biology), order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly", "pomace fly" ...

'' larvae. Feeding experiments with -13Ccetate revealed a polyketidic origin, and feeding experiments with l- ethyl-13Cethionine revealed methyl branching likely via S-adenosyl-l-methionine-dependent methyltransferase(s). Additionally,

MALDI-TOF In mass spectrometry, matrix-assisted laser desorption/ionization (MALDI) is an ionization technique that uses a laser energy-absorbing matrix to create ions from large molecules with minimal fragmentation. It has been applied to the analysis of ...

imaging at the mycelial wounding site identified these poylenes as localized at the wounded area. Two putative

allele An allele is a variant of the sequence of nucleotides at a particular location, or Locus (genetics), locus, on a DNA molecule. Alleles can differ at a single position through Single-nucleotide polymorphism, single nucleotide polymorphisms (SNP), ...

s of

polyketide In organic chemistry, polyketides are a class of natural products derived from a Precursor (chemistry), precursor molecule consisting of a Polymer backbone, chain of alternating ketone (, or Carbonyl reduction, its reduced forms) and Methylene gro ...

genes were identified, referred to as ''PPS1'' and ''PPS2''. QRT-PCR monitoring of ''PPS1'' showed up-regulation of this gene after mycelial wounding. The domain architecture was the following for PPS1: KS, AT, DH, MT, KR, ACP, and thus was classified as a highly-reducing

polyketide synthase Polyketide synthases (PKSs) are a family of multi- domain enzymes or enzyme complexes that produce polyketides, a large class of secondary metabolites, in bacteria, fungi, plants, and a few animal lineages. The biosyntheses of polyketides share ...

(HR-PKS). This was the first characterized HR-PKS of basidiomycetic origin and forms its own

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

in comparison to

ascomycete Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...

HR-PKSs, bacterial

-forming PKSs, basidiomycete non-reducing PKSs, and ascomycete non-reducing PKSs. This research was highlighted in the media several times. The fungus also produces fomannoxins and vibralactones. The famonnixins were found to be

phytotoxic Phytotoxins are substances that are poisonous or toxic to the growth of plants. Phytotoxic substances may result from human activity, as with herbicides, or they may be produced by plants, by microorganisms, or by naturally occurring chemical react ...

and the vibralactones were found to be

antifungal An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as ...

.Schwenk et al. (2016) Unexpected Metabolic Versatility in a Combined Fungal Fomannoxin/Vibralactone Biosynthesis. Journal of Natural Products. Additionally, a new prenylphenol, termed cloquetin, was identified from the fungus by NMR.Braesel et al. (2016) Biochemical and genetic basis of orsellinic acid biosynthesis and prenylation in a stereaceous basidiomycete. Fungal Genetics and Biology. Overexpression of two annotated non-reducing polyketide synthases (''PKS1'' and ''PKS2'') in ''

Aspergillus niger ''Aspergillus niger'' is a mold classified within the ''Nigri'' section of the ''Aspergillus'' genus. The ''Aspergillus'' genus consists of common molds found throughout the environment within soil and water, on vegetation, in fecal matter, on de ...

'' and subsequent characterization of the proteins identified them as orsellinic acid synthases. A

prenyltransferase Prenyltransferases (PTs) are a class of enzymes that transfer allylic prenyl groups to acceptor molecules. Prenyl transferases commonly refer to isoprenyl diphosphate syntheses (IPPSs). Prenyltransferases are a functional category and include seve ...

gene, termed ''BYPB'', was overexpressed in ''

E. coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escherichia'' that is commonly foun ...

'' and the subsequent protein was confirmed to add a prenyl group to orsellinic acid.

References

{{Taxonbar, from=Q48996387 Undescribed species Stereaceae