Message - 7th IAL Symposium

The 7 th International Association for Lichenology Symposium 2012
(1I-P5) Submission ID: IAL0196-00001
SYMBIOTIC CYANOBACTERIA PRODUCE A SERIES OF HEPATOTOXINS IN LICHENS
Kaasalainen U. 1 , Fewer D.P. 2 , Jokela J. 2 , Wahlsten M. 2 , Sivonen K. 2 , Rikkinen J. 1
1 Department of Biosciences, University of Helsinki, Helsinki, Finland
2 Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
Approximately ten percent of lichens have cyanobacteria as symbiotic partners. The most common
cyanobacterial genus in lichens is Nostoc, and recent work has shown that some symbiotic Nostoc strains can
produce microcystins in lichen symbiosis. Microcystins and nodularins are hepatotoxic peptides produced mainly
in aquatic environments by several lineages of cyanobacteria and they have been responsible for poisonings
of both humans and livestock. We have screened nearly 800 cyanolichen specimens from five continents for
microcystins and nodularins both by amplifying a part of the gene cluster encoding the enzyme complex responsible
for microcystin production (mcyE) and by detecting the toxins directly from lichen specimens with LC-MS.
98 out of the 797 specimens contained microcystin synthetase genes and/or microcystins, and over 50 chemical
variants of microcystins were detected. We also found nodularins in several lichens this being evidence of
nodularin production in Nostoc. Variation in toxin production between different geographical locations and lichen
species and genera was considerable, but the presence of mcyE gene and toxins clearly depended more on the
identity of the fungal partner than the geographic origins of lichen specimens. Interestingly, the mcyE genes of
lichen symbiotic Nostoc were highly diverse and the phylogenetic trees compiled from cyanobacterial mcyE and
16S rRNA gene sequences obtained from the same lichen samples were partly incongruent. As a whole, our
results demonstrate that microcystins in lichens are not a rare phenomenon, but occur in many different lichen
species all over the world.
(1I-P6) Submission ID: IAL0200-00001
CONTRIBUTION TO THE KNOWLEDGE OF LICHENICOLOUS FUNGI OF SPAIN
Fernández-Brime, S. 1 , Llop, E. 1 , Gaya, E. 2 , Navarro-Rosinés, P. 1 & Llimona, X. 1
1 Department of Plant Biology (Botany), Universitat de Barcelona, Barcelona, Spain
2 Department of Biology, Duke University, Durham, North Carolina 27708-0338, USA.
As part of a broader study on the lichen flora of the Cap de Creus Natural Park (covering an area of 10,780
hectares in the eastern part of the Pyrenees in north-east Spain), a survey was made of the diversity of the
lichenicolous fungal flora. Thirty two species of lichenicolous fungi belonging to 13 genera were identified,
including four species that were new to science: Cercidospora sp., growing on Caloplaca irrubescens (distinguished
from Cercidospora caudata s.s. by the number of spores per ascus and the host lichen species);
Lichenostigma sp., growing on Pertusaria monogona, (similar to L. rupicolae, but with different hyphal strands
structures, ascospores, and host lichen); Llimoniela sp. growing on Trapeliopsis wallrothii; and Zwackhiomyces
sp. growing on Endocarpon pusillum. In addition, several other lichenicolous species were reported for the first
time on the Iberian Peninsula: Endococcus buelliae, Polycoccum rinodinae, and P. teresum. 34 lichen taxa were
found to host lichenicolous fungi, with the genera Aspicila, Caloplaca, and Lecanora harboring the largest number
of lichenicolous species. A list for these lichen hosts is provided, with descriptions of novel associations with
lichenicolous species. By adding to our knowledge of the diversity of lichenicolous fungi, this study illustrates the
continuing need to investigate this little known group.
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