Polyphasic taxonomy of the heat resistant ascomycete genus <I>Byssochlamys</I> and its <I>Paecilomyces</I> anamorphs

Abstract

Byssochlamys and related Paecilomyces strains are often heat resistant and may produce mycotoxins in contaminated pasteurised foodstuffs. A comparative study of all Byssochlamys species was carried out using a polyphasic approach to find characters that differentiate species and to establish accurate data on potential mycotoxin production by each species. Phylogenetic analysis of the ITS region, parts of the β-tubulin and calmodulin genes, macro- and micromorphological examinations and analysis of extrolite profiles were applied. Phylogenetic analyses revealed that the genus Byssochlamys includes nine species, five of which form a teleomorph, i.e. B. fulva, B. lagunculariae, B. nivea, B. spectabilis and B. zollerniae, while four are asexual, namely P. brunneolus, P. divaricatus, P. formosus and P. saturatus. Among these, B. nivea produces the mycotoxins patulin and byssochlamic acid and the immunosuppressant mycophenolic acid. Byssochlamys lagunculariae produces byssochlamic acid and mycophenolic acid and thus chemically resembles B. nivea. Some strains of P. saturatus produce patulin and brefeldin A, while B. spectabilis (anamorph P. variotii s.s.) produces viriditoxin. Some micro- and macromorphological characters are valuable for identification purposes, including the shape and size of conidia and ascospores, presence and ornamentation of chlamydospores, growth rates on MEA and CYA and acid production on CREA. A dichotomous key is provided for species identification based on phenotypical characters.

Paecilomyces niveus Stolk & Samson, 1971 (Ascomycota: Thermoascaceae) as a pathogen of Nasonovia ribisnigri (Mosley, 1841) (Hemiptera, Aphididae) in Brazil

“…ITS sequencing and phylogenetic analysis indicated that the isolate (PaePR) obtained in this study was clustered with its teleomorph, B. nivea. Samson et al (2009) verified by phylogenetic analyses that the genus Byssochlamys includes nine species, five of which form teleomorphs, i.e., B. fulva, B. lagunculariae, B. nivea, B. spectabilis and B. zollerniae, whereas four are asexual, namely P. brunneolus, P. divaricatus, P. formosus, and P. saturatus. This is the first report of P. niveus as a parasite of N. ribisnigri in Brazil.…”

“…Hypocreales (Ascomycota) can be important for reducing aphid populations (Steinkraus, 2006). According to Samson et al (2009) the genus Byssochlamys is morphologically well defined and characterized by almost naked ascomata in which croziers and globose asci are formed with ellipsoidal ascospores. All Byssochlamys species have a Paecilomyces anamorph that belongs to the Paecilomyces sect.…”

Mycotoxins: Producing Fungi and Mechanisms of Phytotoxicity

“…It has been isolated from P. expansum [79] (P. leucopus [80], P. vulpinum [17] (P. claviforme [68]), P. griseofulvum [79] (P. patulum [69]), P. carneum, P. clavigerum, P. concentricum, P. coprobium, P. dipodomyicola, P. glandicola, P. gladioli, P. marinum, P. paneum, P. sclerotigenum [81], P. cyclopium [82], P. granulatum (P. divergens [83]), P. melinii, P. lapidosum [82], P. aurantiogriseum, P. canescens, P. chrysogenum, P. roqueforti, P. variabile [78], P. purpurogenum [84], Aspergillus clavatus, A. giganteus, A. longivesica [85], A. terreus [86], Byssochlamys fulva, B. nivea and Paecilomyces saturatus [87,88]. PAT has been detected in apples and apple products, and occasionally in other fruits such as pears, apricots, peaches and grapes [77].…”

A critical review of producers of small lactone mycotoxins: patulin, penicillic acid and moniliformin

“…The reports of patulin production by P. roqueforti (Cakmakci et al, 2015;Chunmei et al, 2013;Erdogan et al, 2003;Leistner and Pitt, 1977;Malekinejad et al, 2015;Müller and Amend, 1997;Olivigni and Bullerman, 1978;Paterson et al, 2003;Steiman et al, 1989;Vismer et al, 1996) appear to be caused by misidentifications, because the closely related species P. carneum and P. paneum both produce patulin (Boysen et al, 1996). Paecilomyces fulvus (formerly Byssochlamyes fulva), Puel et al, 2007), but these species all have heat resistant ascospores (Samson et al, 2009), and thus may survive in pasteurised fruit juices and produce patulin (Rice et al, 1977;Sant' Ana et al, 2010). Paecilomyces niveus and Penicillium paneum can grow in substrates with a high concentration of acetic acid and thus can also be found in silage, and may produce patulin there (Gallo et al, 2015;O'Brien et al, 2006;Scurti et al, 1973).…”