Terricolous Lichens in the Glacier Forefield of the Pasterze (Eastern Alps, Carinthia, Austria).

The investigation of lichens on soil, plant debris and terricolous mosses in the glacier forefield of the Pasterze yielded 35 lichen species. Placidiopsis oreades Breuss (Verrucariales) is new to Austria. Three sampling sites were established at increasing distance from the glacier, in order to compare species diversity, abundance and composition within the forefield and with four other glacier forefields of the Eastern Alps.

Terricolous Lichens in the Glacier Forefield of the Rötkees (Eastern Alps, South Tyrol, Italy).

The investigation of lichens on soil, plant debris and terricolous mosses in the glacier forefield of the Rötkees yielded 31 lichen taxa (29 species and 2 varieties) and one lichenicolous fungus. Micarea incrassata Hedl. (Lecanorales) is new to Italy. Three sampling sites were established at increasing distance from the glacier, in order to compare species diversity, abundance and composition.

Terricolous Lichens in the Glacier Forefield of the Gaisbergferner (Eastern Alps, Tyrol, Austria).

The investigation of lichens on soil, plant debris and terricolous mosses in the glacier forefield of the Gaisbergferner yielded 41 lichen taxa (39 species and 2 varieties) and one lichenicolous fungus. Three sampling sites were established at increasing distance from the glacier, in order to compare species diversity, abundance and composition.

Distinct roles for intra- and extracellular siderophores during Aspergillus fumigatus infection.

Siderophore biosynthesis by the highly lethal mould Aspergillus fumigatus is essential for virulence, but non-existent in humans, presenting a rare opportunity to strategize therapeutically against this pathogen. We have previously demonstrated that A. fumigatus excretes fusarinine C and triacetylfusarinine C to capture extracellular iron, and uses ferricrocin for hyphal iron storage. Here, we delineate pathways of intra- and extracellular siderophore biosynthesis and show that A. fumigatus synthesizes a developmentally regulated fourth siderophore, termed hydroxyferricrocin, employed for conidial iron storage. By inactivation of the nonribosomal peptide synthetase SidC, we demonstrate that the intracellular siderophores are required for germ tube formation, asexual sporulation, resistance to oxidative stress, catalase A activity, and virulence. Restoration of the conidial hydroxyferricrocin content partially rescues the virulence of the apathogenic siderophore null mutant Delta sidA, demonstrating an important role for the conidial siderophore during initiation of infection. Abrogation of extracellular siderophore biosynthesis following inactivation of the acyl transferase SidF or the nonribosomal peptide synthetase SidD leads to complete dependence upon reductive iron assimilation for growth under iron-limiting conditions, partial sensitivity to oxidative stress, and significantly reduced virulence, despite normal germ tube formation. Our findings reveal distinct cellular and disease-related roles for intra- and extracellular siderophores during mammalian Aspergillus infection.

Ferricrocin, a siderophore involved in intra- and transcellular iron distribution in Aspergillus fumigatus.

Iron is an essential metal for virtually all organisms. Iron acquisition is well characterized for various organisms, whereas intracellular iron distribution is poorly understood. In contrast to bacteria, plants, and animals, most fungi lack ferritin-mediated iron storage but possess an intracellular siderophore shown to be involved in iron storage. Here we demonstrate that deficiency in the intracellular siderophore ferricrocin causes iron starvation in conidia of Aspergillus fumigatus, demonstrating that ferricrocin is also involved in intra- and transcellular iron distribution. Thus, ferricrocin represents the first intracellular iron transporter identified in any organism.

Terricolous lichens in the glacier forefield of the Matscherferner (Eastern Alps, South Tyrol, Italy).

Two sampling sites were established at increasing distance from the glacier to investigate lichen communities on soil, plant debris and terricolous mosses in the glacier forefield of the Matscherferner. The survey yielded 34 lichen species and one lichenicolous fungus. In addition, 19 lichen species and one lichenicolous fungus were found by collecting at random, outside the two sampling sites.