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Candida albicans is a major cause of oropharyngeal, vulvovaginal and hematogenously disseminated candidiasis. Endocytosis of C. albicans hyphae by host cells is a prerequisite for tissue invasion. This internalization involves interactions between the fungal invasin Als3 and host E- or N-cadherin. Als3 shares some structural similarity with InlA, a major invasion protein of the bacterium Listeria monocytogenes. InlA mediates entry of L. monocytogenes into host cells through binding to E-cadherin. A role in internalization, for a non classical stimulation of the clathrin-dependent endocytosis machinery was recently highlighted. Based on the similarities between the C. albicans and L. monocytogenes invasion proteins, we studied the role of clathrin in the internalization of C. albicans. Using live-cell imaging and indirect immunofluorescence of epithelial cells infected with C. albicans, we observed that host E-cadherin, clathrin, dynamin and cortactin accumulated at sites of C. albicans internalization. Similarly, in endothelial cells, host N-cadherin, clathrin and cortactin accumulated at sites of fungal endocytosis. Furthermore, clathrin, dynamin or cortactin depletion strongly inhibited C. albicans internalization by epithelial cells. Finally, beads coated with Als3 were internalized in a clathrin-dependent manner. These data indicate that C. albicans, like L. monocytogenes, hijacks the clathrin-dependent endocytic machinery to invade host cells.

Purpose Version 3 of ecoinvent includes more data, new modeling principles, and, for the first time, several system models: the BAllocation, cut-off by classification^(Cut-off) system model, which replicates the modeling principles of version 2, and two newly introduced models called BAllocation at the point of substitution^(APOS) and BConsequential ( Wernet et al. 2016). The aim of this paper is to analyze and explain the differences in life cycle impact assessment (LCIA) results of the v3.1 Cut-off system model in comparison to v2.2 as well as the APOS and Consequential system models. Methods In order to do this, functionally equivalent datasets were matched across database versions and LCIA results compared to each other. In addition, the contribution of specific sectors was analyzed. The importance of new and updated data as well as new modeling principles is illustrated through examples.Results and discussion Differences were observed in between all database versions using the impact assessment methods Global Warming Potential (GWP100a), ReCiPe Endpoint (H/ A), and Ecological Scarcity 2006 (ES'06). The highest differences were found for the comparison of the v3.1 Cut-off and v2.2. At average, LCIA results increased by 6, 8, and 17 % and showed a median dataset deviation of 13, 13, and 21 % for GWP, ReCiPe, and ES'06, respectively. These changes are due to the simultaneous update and addition of new data as well as through the introduction of global coverage and spatially consistent linking of activities throughout the database. As a consequence, supply chains are now globally better represented than in version 2 and lead, e.g., in the electricity sector, to more realistic life cycle inventory (LCI) background data. LCIA results of the Cut-off and APOS models are similar and differ mainly for recycling materials and wastes. In contrast, LCIA results of the Consequential version differ notably from the attributional system models, which is to be expected due to fundamentally different modeling principles. The use of marginal instead of average suppliers in markets, i.e., consumption mixes, is the main driver for result differences. Conclusions LCIA results continue to change as LCI databases evolve, which is confirmed by a historical comparison of v1.3 and v2.2. Version 3 features more up-to-date background data as well as global supply chains and should, therefore, be used instead of previous versions. Continuous efforts will be required to decrease the contribution of Rest-of-theWorld (RoW) productions and thereby improve the global coverage of supply chains.

The fungal cell wall is essential in maintaining cellular integrity and plays key roles in the interplay between fungal pathogens and their hosts. The PGA59 and PGA62 genes encode two short and related glycosylphosphatidylinositol-anchored cell wall proteins and their expression has been previously shown to be strongly upregulated when the human pathogen Candida albicans grows as biofilms. Using GFP fusion proteins, we have shown that Pga59 and Pga62 are cell-walllocated, N-and O-glycosylated proteins. The characterization of C. albicans pga59D/pga59D, pga62D/pga62D and pga59D/pga59D pga62D/pga62D mutants suggested a minor role of these two proteins in hyphal morphogenesis and that they are not critical to biofilm formation. Importantly, the sensitivity to different cell-wall-perturbing agents was altered in these mutants. In particular, simultaneous inactivation of PGA59 and PGA62 resulted in high sensitivity to Calcofluor white, Congo red and nikkomicin Z and in resistance to caspofungin. Furthermore, cell wall composition and observation by transmission electron microscopy indicated an altered cell wall structure in the mutant strains. Collectively, these data suggest that the cell wall proteins Pga59 and Pga62 contribute to cell wall stability and structure. INTRODUCTIONThe cell wall is an essential component of fungal cells, preserving cellular integrity and playing a central role in the interaction of fungi with their environment. This is particularly the case for pathogenic fungi such as the opportunistic yeast pathogen Candida albicans, where the cell wall has been shown to play central roles in adhesion, virulence, biofilm formation, infection and immunomodulation (Albrecht et al., 2006;Douglas, 2003;Netea et al., 2006;Richard et al., 2002b;Sundstrom, 2002). Because of the essential role of the cell wall in cellular integrity and fungal specificity of some enzymes involved in its biogenesis, it is a recognized target for the development of novel antifungals (e.g. echinocandins that target the b-1,3-glucan synthase) (Latge, 2007).The organization of the fungal cell wall has been mainly characterized in the yeasts Saccharomyces cerevisiae and C. albicans and in the filamentous fungus Aspergillus fumigatus (Klis et al., 2006;Latge, 2007;Lesage & Bussey, 2006;Ruiz-Herrera et al., 2006). The yeast cell wall has a bilayered structure. The inner part is composed of a network of b-1,3-glucan molecules linked by hydrogen bonds. These chains can be bound covalently to b-1,6-glucan molecules and to chitin chains. The outer part of the cell wall is composed mainly of mannoproteins (Klis et al., 2006Lesage & Bussey, 2006). Most proteins in the cell wall of ascomycetous yeasts are glycosylphosphatidylinositolanchored proteins (GPI-modified proteins) that become covalently linked to b-1,6-glucan through a remnant of their GPI anchor. As the b-1,6-glucan moiety can be linked to b-1,3-glucan or chitin, the cell wall GPI-modified proteins are strongly linked to the cell wall Klis et al., 2001;Richard & Plaine, 2007).GPI-...