naa a22 4500 510746780 CHVBK 20180411092755.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s13199-012-0219-6 doi (NATIONALLICENCE)springer-10.1007/s13199-012-0219-6 Recognition mechanisms during the pre-contact state of lichens: II. Influence of algal exudates and ribitol on the response of the mycobiont of Fulgensia bracteata [Elektronische Daten] [Joachim Meeßen, Sandra Eppenstein, Sieglinde Ott] Successful re-lichenization between the two bionts of the lichen symbiosis, the fungal mycobiont and its specific photobiont, is a process that is not well understood yet. To assess potential signalling between the two bionts during initial pre-contact, exudates of the Trebouxia photobionts of Fulgensia bracteata, Fulgensia fulgens, and Xanthoria elegans, of the Asterochloris photobiont of Lecidea lurida, and of the non-lichenizing green alga Myrmecia bisecta were investigated. The compounds identified in these exudates were tested with respect to their influence on germination and early development of the Fulgensia bracteata mycobiont. Additionally, carbohydrates (glucose, sucrose, ribitol) were tested to appraise their effect on the mycobiont growth patterns. Three hypotheses were confirmed: (i) photobionts exude various substances, (ii) the photobiont exudation pattern varies with the identity of the photobiont, and (iii) a pre-contact influence induces changes in the early development of the mycobiont of F. bracteata. This study gives comparative insight to exudates of lichen photobionts. In vitro photobionts differentially release compounds belonging to several substance classes which include indole-3-carbaldehyde, two cyclic dipeptides, and rhamnose. Two compounds had inhibitory effects on germination and germ-tube growth of the mycobiont and one other enhanced spore germination. Additionally, ribitol was found to elicit a strong effect on the mycobiont's growth. In general, photobiont-exudation, its effect on the mycobiont, and the response to ribitol suggest that complex pre-contact signalling has a crucial role in lichen biont recognition. Springer Science+Business Media Dordrecht, 2013 Fulgensia bracteata nationallicence Trebouxia sp nationallicence Asterochloris sp nationallicence Photobiont exudates nationallicence Biont recognition nationallicence Lichenization nationallicence CLT : Cyclo-(L-leucyl-L-tyrosyl) nationallicence CTT : Cyclo-(L-tryptophyl-L-tryptophyl) nationallicence EIMS : Electron impact mass spectrometry nationallicence HPLC : High performance liquid chromatography nationallicence IAA : Indole-3-acetic acid nationallicence ICA : Indole-3-carbaldehyde nationallicence ITS rDNA : Internal transcribed spacer ribosomal DNA nationallicence LCMS : Liquid chromatography-mass spectrometry nationallicence MeOH : Methanol nationallicence PPFD : Photosynthetic photon flux density nationallicence R f : Retardation factor nationallicence TLC : Thin layer chromatography nationallicence TOM : Trebouxia Organic Medium nationallicence UV/VIS : Ultraviolet/visible light nationallicence Meeßen Joachim Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut Eppenstein Sandra Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut Ott Sieglinde Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut Symbiosis Springer Netherlands 59/3(2013-03-01), 131-143 0334-5114 59:3<131 2013 59 13199 https://doi.org/10.1007/s13199-012-0219-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s13199-012-0219-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Meeßen Joachim Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut NATIONALLICENCE 700 1- Eppenstein Sandra Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut NATIONALLICENCE 700 1- Ott Sieglinde Institute of Botany, Heinrich-Heine-University, Universitaetsstr.1, 40225, Duesseldorf, Germany aut NATIONALLICENCE 773 0- Symbiosis Springer Netherlands 59/3(2013-03-01), 131-143 0334-5114 59:3<131 2013 59 13199 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 510746756 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer