Talaromyces Species Research Articles

Delimitation and characterisation of <I>Talaromyces purpurogenus </I> and related species

Taxa of the Talaromyces purpurogenus complex were studied using a polyphasic approach. ITS barcodes were used to show relationships between species of the T. purpurogenus complex and other Talaromyces species. RPB1, RPB2, β-tubulin and calmodulin sequences were used to delimit phylogenetic species in the complex. These data, combined with phenotypic characters, showed that the complex contains four species: T. purpurogenus, T. ruber comb. nov. and two new species T. amestolkiae sp. nov. and T. stollii sp. nov. The latter three species belong to the same clade and T. purpurogenus is located in a phylogenetic distant clade. The four species all share similar conidiophore morphologies, but can be distinguished by macromorphological characters. Talaromyces ruber has a very distinct colony texture on malt extract agar (MEA), produces bright yellow and red mycelium on yeast extract sucrose agar (YES) and does not produce acid on creatine sucrose agar (CREA). In contrast, T. amestolkiae and T. stollii produce acid on CREA. These two species can be differentiated by the slower growth rate of T. amestolkiae on CYA incubated at 36 °C. Furthermore, T. stollii produces soft synnemata-like structures in the centre of colonies on most media. Extrolite analysis confirms the distinction of four species in the T. purpurogenus complex. The red diffusing pigment in T. purpurogenus is a mixture of the azaphilone extrolites also found in Monascus species, including N-glutarylrubropunctamine and rubropunctatin. Talaromyces purpurogenus produced four different kinds of mycotoxins: rubratoxins, luteoskyrin, spiculisporic acid and rugulovasins and these mycotoxins were not detected in the other three species.

Three new additions to the genus Talaromyces isolated from Atlantis sandveld fynbos soils.

During a survey of Penicillium spp. in soils from the diverse fynbos region in the Western Cape, South Africa, a number of previously undescribed species were isolated. Three of these belong to subg. Biverticillium sensu Pitt, recently incorporated into its previously associated teleomorph genus, Talaromyces s.str. These species displayed symmetrical biverticillate penicilli, acerose phialides and poor growth at reduced water activity, typical of this group. Morphological characters of the new species were compared to known Talaromyces species. The ITS and β-tubulin gene regions were used for phylogenetic comparisons, which confirmed the distinct nature of the three fynbos soil species described here as Talaromyces chloroloma sp. nov., T. ptychoconidium sp. nov. and T. solicola sp. nov., respectively. Talaromyces chloroloma is typically recognised by its strongly funiculose colony texture and after prolonged incubation, synnemata can be observed on CYA. Talaromyces ptychoconidium is characterised by closely appressed conidiophores that produce spirally rough-walled conidia, while T. solicola typically struggle to grow on CYA and is distinguished from similar species by its prominently rough-walled, spheroid conidia.

Genus Hamigera, six new species and multilocus DNA sequence based phylogeny

Genus Hamigera was erected for Talaromyces species that make asci singly instead of in chains. Initially it contained two species, H. avellanea and H. striata. We describe six new species in the genus, H. fusca, H. inflata, H. insecticola, H. pallida, H. paravellanea and H. terricola. Merimbla ingelheimensis is a distinct anamorphic species in the Hamigera clade. None of our DNA sequence data (BT2, calmodulin, ITS, lsu rDNA, RPB2, Tsr1 and Mcm7) supported the placement of H. striata in the same clade as H. avellanea, thus we accepted Talaromyces striatus. In addition to Hamigera species we examined the phylogenetic disposition of Warcupiella spinulosa, Penicillium megasporum, Penicillium arenicola and Merimbla humicoloides. Despite nominal similarity of some of these species to Merimbla, none of these species are part of the Hamigera clade and M. humicoloides is placed in Penicillium to have a monophyletic genus Hamigera.

Bioconversion of Straw into Improved Fodder: Fungal Flora Decomposing Rice Straw

The fungal flora decomposing rice straw were investigated all over the soil of Sharkia Province, east of Nile Delta, Egypt, using the nylon net bag technique. Sixty-four straw-decomposing species belonging to 30 genera were isolated by the dilution plate method in ground rice straw-Czapek’s agar medium at pH 6. The plates were incubated separately at 5°C, 25°C and 45°C, respectively. Twenty nine species belonging to 14 genera were isolated at 5°C. The most frequent genus was Penicillium (seven species), and the next frequent genera were Acremonium (three species), Fusarium (three species), Alternaría, Chaetomium, Oadosporium, Mucor, Stachybotrys (two species) and Rhizopus stolonifer. At 25°C, 47 species belonging to 24 genera were isolated. The most frequent genus was Aspergillus (nine species), and the next frequent genera were ranked by Penicillium (five species), Chaetomium (three species), Fusarium (three species). Each of Alternaria, Cladosporium, Mucor, Myrotlt- ecium and Trichoderma was represented by two species. At 45°C, 15 species belonging to seven genera were isolated. These were seven species of Aspergillus, two species of Chaetomium and two species of Emericella, while Humicola, Malbranchea, Rhizomucor and Talaromyces were represented by one species respectively. The total counts of fungi the genera, and species per gram of dry straw were significantly affected by incubation temperature and soil analysis (P<0.05).

Talaromyces ocotl sp. nov. and Observations on T. rotundus from Conifer Forest Soils of Veracruz State, Mexico

Two unusual Talaromyces species were encountered by using heat and chemical pasteurization techniques to survey soil fungi in Pinus hartwegii and Pinus patula forests of the Volcanic Cordillera of Veracruz state, Mexico. Talaromyces ocotl is described as a new species based on morphological analyses and phylogenetic inferences made from ITS and 28S rDNA sequence alignments. The geographic range of Talaromyces rotundus is extended to Mexico and its relationship to other Talaromyces species is investigated based on ITS sequence alignments.

Talaromyces ocotl sp. nov. and observations on T. rotundus from conifer forest soils of Veracruz State, Mexico

Two unusual Talaromyces species were encountered by using heat and chemical pasteurization techniques to survey soil fungi in Pinus hartwegii and Pinus patula forests of the Volcanic Cordillera of Veracruz state, Mexico. Talaromyces ocotl is described as a new species based on morphological analyses and phylogenetic inferences made from ITS and 28S rDNA sequence alignments. The geographic range of Talaromyces rotundus is extended to Mexico and its relationship to other Talaromyces species is investigated based on ITS sequence alignments.

Galactomannans from the cell walls of species of Paecilomyces sect. Paecilomyces and their teleomorphs as immunotaxonomic markers.

An alkali-extractable and water-soluble fraction (F1S) was obtained from cell walls of Paecilomyces variotii and species of the related genera Talaromyces, Byssochlamys and Thermoascus. The structure of the main polysaccharide of these fractions was studied and found to consist of a core of (1 --> 6)-alpha-mannopyranose partially substituted at 0.2 by chains of galactofuranose and shorter chains of mannopyranose. The differences in the regularity of the branching points and the length of the galactofuranose side chains are useful to distinguish between species. These differences were detected by immunological methods, since highly specific polyclonal antibodies were raised against these polysaccharides. Mycelium of P. variotii CBS 990.73A was stained by indirect immunofluorescence. The polysaccharides studied in this work differ from the one described for species from section Isarioidea, and this is another indication of the heterogeneity of the genus Paecilomyces.

Talaromyces euchlorocarpius, a new species from soil

A new species ofTalaromyces, characterized by development of unusual deep green ascomata on common media, is described and given the nameTalaromyces euchlorocarpius. This species, isolated from soil, also produces ellipsoidal, spinose ascospores, typically biverticillate penicilli, large ellipsoidal, smooth-walled conidia, and is assigned to the seriesLutei of the sectionTalaromyces.

Polyphyletic origins of species of the anamorphic genus Geosmithia and the relationships of the cleistothecial genera: Evidence from 18S, 5S and 28S rDNA sequence analyses

The anamorphic genus Geosmithia, with the type species G. lavendula, includes species strictly lacking a teleomorph as well as species associated with the teleomorphs Talaromyces and Chromocleista. Our 18S rDNA sequence-based tree, inferred from 1586 alignable sites from 57 selected taxa within the Ascomycota and using two basidiomycetes as out-groups, clearly demonstrates that Geosmithia is a polyphyletic taxon with evolutionary affinities to at least three groups of the euascomycete lineage within the Ascomycota: (1) Geosmithia lavendula, the type of the genus, G. putterilli, and the hypocrealean fungi, Gliodadium-producing Hypocrea lutea and Verticillium/Sepedonium-producing Hypomyces chrysogenum within the pyrenomycete lineage, appear as a monophyletic group with 100% bootstrap support; (2) G. cylindrospora and the Geosmithia-producing Talaromyces species (i.e., T. bacillisporus, T. ebruneus, and T. emerson- ii) group with the Penicillium-producing T. flavus var. macrosporus of the Trichocomaceae within the plectomycete lineage in 57% of bootstrap replicates; (3) G. namyslowskii, the Geosmithia-producing Chromocleista malachitea, the Penicillium-producing Eupenicillium crustaceum and the Merimbla-producing Talaromyces avellaneus (≡ Hamigera avellanea) of the same higher categories appear to be a monophyletic group in 74% of bootstrap replicates. The bootstrapped NJ and MP analyses, using 1706 sites of the same gene only from plectomycetes and pyrenomycetes, demonstrate similar phylogenetic relationships. The bootstrapped NJ and MP analyses, based on 70 alignable sites of 5S rDNA, support the results from 18S rDNA sequence analyses. Within the Hypocreales, G. lavendula and G. putterillii group with the hypocrealean fungi, cleistothecial, Acremonium-producing Mycoarachis inversa and Emericellopsis terricola, and the strictly anamorph species of Acremonium-in 66% or greater of the bootstrapped NJ and MP trees derived from 28S rDNA partial (580 sites) sequences. Phylogenetic considerations are also presented for several cleistothecial taxa.

Isolation and identification of Neosartorya species from house dust as hazardous indoor pollutants

Isolation of ascomycetous microfungi from 58 house dust samples from detached and apartment dwellings around Kobe City revealed that species ofTalaromyces, Eurotium andNeosartorya were common ascomycetous propagules in the house dust.Neosartorya species accounted for 8.3% of the total identified isolates, of whichN. pseudofischeri was the main constituent, indicating that it may be a common potential fungal pathogen in the dwelling environment. Based on the specimens collected,N. pseudofischeri is described and illustrated as new to Japan.

New and rare microfungi from the island of Hachijo-jima

Two striking fungi, isolated from soils from the island of Hachijo-jima in Japan, are described and illustrated. One of these represents a new species ofTalaromyces (Ascomycetes), for which the nameTalaromyces hachijoensis is proposed. The new species is distinctive among all other recognized species in its restricted growth on common media, yellow ascomata characterized by asci developing in chains, striate ascospores, and the absence of an anamorph. The other isHeterocephalum taiense, a rare hyphomycete which has only previously been recorded from lvory Coast soil and probably from Panama soil.

Phylogeny and PCR identification of the human pathogenic fungus Penicillium marneffei

The phylogenetic position of the human pathogenic fungus Penicillium marneffei was assessed from the nucleotide sequences of the nuclear and mitochondrial ribosomal DNA regions. Phylogenetic analysis determined that P. marneffei is closely related to species of Penicillium subgenus Biverticillium and sexual Talaromyces species with asexual biverticillate Penicillium states. Knowledge of the phylogenetic position of P. marneffei facilitated the design of unique oligonucleotide primers, from the nuclear ribosomal DNA internal transcribed spacer region, for the specific amplification of P. marneffei DNA. These primers were successful at selectively amplifying DNA from six isolates of P. marneffei and excluding the other species tested, which included Penicillium subgenus Biverticillium and Talaromyces species and several well-known fungal pathogens, namely, Aspergillus fumigatus, Coccidioides immitis, Histoplasma capsulatum, and Pneumocystis carinii. The primers that we have developed for the specific amplification of P. marneffei have the potential to be incorporated in a PCR identification system which could be used for the identification of this pathogenic agent from clinical material.

Isolation, purification and chemical characterization of alkali-extractable polysaccharides from the cell walls of Talaromyces species

From the alkali-extractable material from cell walls of some species of Talaromyces a water-extractable (F1S) and a water-unextractable (F1I) fraction were obtained. Fraction F1S (representing 2·5–12·5% of the cell wall) was filtered through Sepharose CL-6B in order to purify polysaccharides that were individually studied for chemical composition and structure. According to the structure of these polysaccharides, the species investigated could be grouped as follows: T. stipitatus, T. bacillisporus and T. macrosporus had as their main component a heteropolysaccharide containing β-(1 → 2) and β-(1 → 5) galactofuranosyl residues; in T. wortmannii and T. rotundus the most abundant component was a polysaccharide with β-(1 → 2) and β-(1 → 3)-linked galactofuranose; T. luteus contained in fraction F1S a single polysaccharide, identified as a highly branched galacto-gluco-mannan. Fraction F1I was identified as an α-glucan in most of the species. These results reflect the complexity of the genus and could have chemotaxonomic value.

Talaromyces lagunensis, a new species from Philippine soil

A new species ofTalaromyces (Ascomycetes; Trichocomaceae) with aPenicillium anamorph,T. lagunensis, is described and illustrated. This fungus is characterized by its extremely restricted growh on Czapek-yeast extract agar, light yellow to light orange ascomata with a telaperidium, catenate, pyriform or ellipsoidal asci, ellipsoidal or subglobose ascospores with a microtuberculate wall, short conidiophores with an irregular, mostly monoverticillate to biverticillate penicillus, and subglobose to ovoid conidia. The holotype was isolated from forest soil in the Philippines.

Two new species of Talaromyces from Taiwan and Japan

Two new species ofTalaromyces, isolated from soils in Taiwan and Japan, are described and illustrated.Talaromyces eburneus, associated with aGeosmithia anamorph, is characterized by off-white colony on oatmeal agar, small pale yellow ascomata, and subglobose to ovoid ascospores with a smooth wall.Talaromyces muroii is characterized by restricted growth on Czapek agar, luteous ascomata, which are initiated by paired gametangia like those seen in members of the seriesFlavi, ellipsoidal and nearly smooth ascospores, and the absence of an anamorph.

Phylogenetic Analysis of Two Ribosomal DNA Regions Indicates Multiple Independent Losses of a Sexual Talaromyces State among Asexual Penicillium Species in Subgenus Biverticillium

Nucleotide sequences were obtained from the mitochondrial small subunit ribosomal DNA, and the nuclear ribosomal DNA region containing the internal transcribed spacers and 5.8S ribosomal RNA gene for 10 Talaromyces species and six Penicillium species in subgenus Biverticillium. Phylogenetic analysis of the Talaromyces species shows that the majority of the species examined formed a major Talaromyces clade, but that sections and series proposed for these species may not reflect their phylogenetic relationships. Incorporating the strictly mitotic Penicillium species with the meiotic Talaromyces in the phylogenetic analysis demonstrated that the majority of mitotic species have meiotic species as their closest relatives. Thus, multiple independent losses of a meiotic Talaromyces state have occurred among Penicillium species in subgenus Biverticillium. Examination of base substitution patterns for each ribosomal DNA region indicated that the mitochondrial small subunit ribosomal DNA is adenine-thymine rich and biased towards adenine-guanine transitions. The internal transcribed spacers and 5.8S ribosomal RNA gene is guanine-cytosine rich and biased towards cytosine-thymine and thymine-cytosine base transitions. Although these molecules vary in their tempo and mode of evolution, trees generated independently for each ribosomal DNA region from bootstrap analysis had identical topologies in all statistically significant branches.

Chemotaxonomy of the genus Talaromyces

Species of the ascomycetous genus Talaromyces have been examined for profiles of secondary metabolites on TLC. The greatest number of specific metabolites were produced on oatmeal-, malt extract- and yeast-extract sucrose agars. Profiles of intracellular secondary metabolites produced on oatmeal agar were specific for each species and provided a means of simple differentiation of the taxa. Examination of the most important species using high performence liquid chromatography (HPLC) allowed to solve some taxonomic problems. Known mycotoxins are produced by T. stipitatus (duclauxin, talaromycins, botryodiploidin), T. stipitatus chemotype II (emodin), T. panasenkoi (spiculisporic acid), T. trachyspermus (spiculisporic acid), T. macrosporus (duclauxin) and T. wortmannii (rugulosin). Wortmannin is produced by an atypical strain of T. flavus but not T. wortmannii. Several other secondary metabolites were discovered for the first time in the following species: Glauconic acid is produced by T. panasenkoi, T. ohiensis and T. trachyspermus; vermiculine by T. ohiensis; duclauxin by T. flavus var. macrosporus and the mitorubrins by T. flavus and T. udagawae. The profiles of secondary metabolites support the established taxonomy of the species based on morphology, showing the genetic stability of profiles of secondary metabolites in Talaromyces. Two new taxa are proposed: T. macrosporus comb. nov. (stat. anam. Penicillium macrosporum stat. nov.), and Penicillium vonarxii, sp. nov. for the anamorph of T. luteus.

The use of high-performance liquid chromatography and diode array detection in fungal chemotaxonomy based on profiles of secondary metabolites

FRISVAD, J. C, 1989. The use of high-performance liquid chromatography and diode array detection in fungal chemotaxonomy based on profiles of secondary metabolites. Fungal chemotaxonomy (that part dealing with secondary metabolites) has often been based on thin layer chromatography (TLC) and visual or UV inspection of separated spots, before and after different chemical treatments. The identity of a small proportion of the spots can be suggested based on known internal and external standards. In most chemotaxonomical studies it is impossible to isolate, purify and identify all secondary metabolites produced, due to restraints of time and resources. High performance liquid chromatography (HPLC) of fungal extracts may have some advantages over TLC, but the problems mentioned above remain. These problems have been approached by using an alkylphenone retention time index in a reversed phase HPLC system combined with the use of a diode array UV-VIS detector. High performance thin layer chromatography is used for further confirmation of identity of the secondary metabolites. A particular advantage of this method is that the number of biosynthetic families or groups (‘chemosyndromes’) can be detected, as biosynthetically related metabolites usually have the same chromophores and UV-VIS spectra. Results obtained from Penicillium, Aspergillus and Fusanum species have shown that each species produces 5 to 15 different biosynthetic families of secondaiy metabolites, indicating that good chromatography data may be sufficient to identify species in the three genera. The use of the technique is exemplified by data on Aspergillus and Talaromyces species.

Differences in the cell wall composition in the type species of Eupenicillium and Talaromyces

The polysaccharide fractions extracted with 1 M NaOH from cell walls of Eupenicillum crustaceum (13–18%) and Talaromyces flavus (4–12%), type species of the teleomorphic states of Penicillium, show differences in composition and structure. The material extracted from three isolates of E. crustaceum was characterized as an α-glucan with absorption bands at 850 and 820 cm −1 in the infrared spectrum. Glucose (87–99%) and mannose (1–11%) were detected in 4 N H 2SO 4 hydrolysates by gas-liquid chromatography. This polysaccharide was resistant to periodate oxidation and after complete Smith degradation, the recovery of glucose indicated that the linkage type was predominantly 1–3. The spectrum of the alkali-soluble fraction from three isolates of T. flavus showed an absorption band at 890 cm −1 characteristic of β-linked polysaccharides. The monosaccharides released by 4 N H 2SO 4 hydrolysis were galactose (25–60%), glucose (31–69%), and mannose (6–9%). All the galactose was released by hydrolysis with 0.1 N H 2SO 4, characteristic of a furanose configuration. This polysaccharide consumes 0.73 mol of periodate per hexose residue. The products detected after complete Smith degradation were identified as glycerol, erythritol, threitol, arabinitol, mannitol, galactitol, and glucitol.

Cell wall polysaccharides from Talaromyces species

The neutral sugars and amino sugars, released by acid hydrolysis of walls and polysaccharidic fractions, of six species of Talaromyces and the infrared spectra have been used to study their interspecific relationships. In whole cell walls neutral sugars ranged from 23 to 39.6% dry weight and were identified as glucose, galactose and mannose. Glucosamine varied from 8 to 19.8% in the samples. Galactosamine (2% or less) was found in T. emersonii and T. rotundus and no galactosamine in the other species. Sequential fractionation of the cell walls with alkali and acid gave several polysaccharidic fractions. The main differences among species were found in the alkali-soluble fraction at 20° (F1). This fraction represented 8 to 33.2% of the whole cell wall and was characterized as an α-glucan in T. bacillisporus, T. emersonii, T. luteus and T. rotundus (Group A) and as a β-galactofuranosyl containing glucan in T. ohiensis and T. stipitatus (Group B). The alkali-insoluble residue (F4) represented the bulk of the cell wall in all species tested (33.2% to 57.3%) and was characterized as a β-glucan/chitin complex. The results may indicate degrees of interspecific relationship in the genus Talaromyces.