Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1007/s00792-017-0984-5
Titel (primär) Corrosive extracellular polysaccharides of the rock-inhabiting model fungus Knufia petricola
Autor Breitenbach, R.; Silbernagl, D.; Toepel, J.; Sturm, H.; Broughton, W.J.; Sassaki, G.L.; Gorbushina, A.A.
Quelle Extremophiles
Erscheinungsjahr 2018
Department SOMA
Band/Volume 22
Heft 2
Seite von 165
Seite bis 175
Sprache englisch
Keywords EPS Corrosion α-1,4- and α-1,6-glucans Pullulan Melanised microcolonial fungi (MCF) Sub-aerial biofilms (SAB)
UFZ Querschnittsthemen RU4;
Abstract Melanised cell walls and extracellular polymeric matrices protect rock-inhabiting microcolonial fungi from hostile environmental conditions. How extracellular polymeric substances (EPS) perform this protective role was investigated by following development of the model microcolonial black fungus Knufia petricola A95 grown as a sub-aerial biofilm. Extracellular substances were extracted with NaOH/formaldehyde and the structures of two excreted polymers studied by methylation as well as NMR analyses. The main polysaccharide (~ 80%) was pullulan, also known as α-1,4-; α-1,6-glucan, with different degrees of polymerisation. Αlpha-(1,4)-linked-Glcp and α-(1,6)-linked-Glcp were present in the molar ratios of 2:1. A branched galactofuromannan with an α-(1,2)-linked Manp main chain and a β-(1,6)-linked Galf side chain formed a minor fraction (~ 20%). To further understand the roles of EPS in the weathering of minerals and rocks, viscosity along with corrosive properties were studied using atomic force microscopy (AFM). The kinetic viscosity of extracellular K. petricola A95 polysaccharides (≈ 0.97 × 10−6 m2 s−1) ranged from the equivalent of 2% (w/v) to 5% glycerine, and could thus profoundly affect diffusion-dominated processes. The corrosive nature of rock-inhabiting fungal EPS was also demonstrated by its effects on the aluminium coating of the AFM cantilever and the silicon layer below.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=20068
Breitenbach, R., Silbernagl, D., Toepel, J., Sturm, H., Broughton, W.J., Sassaki, G.L., Gorbushina, A.A. (2018):
Corrosive extracellular polysaccharides of the rock-inhabiting model fungus Knufia petricola
Extremophiles 22 (2), 165 - 175 10.1007/s00792-017-0984-5