Our findings provide more detailed answers to the question raised by Paton et al. in 1984 wondering by which mechanisms human serum intitates complement deposition on PLY in the absence of specific antibodies. We show that in human serum, PLY initiates LP-mediated complement activation via the specific binding of L-ficolin to PLY. CP activation in human serum depends either on the presence of specific antibodies or can be driven by the non-specific binding of PLY to non-immune IgG3 and/or IgM. Surprisingly, PLY does not induce LP activation in mouse serum since none of the murine LP recognition molecules bind to PLY, while both the classical and the alternative pathways can activate C3 on PLY in mouse serum. Previous in vivo studies have shown that PLY is naturally released by S. pneumoniae at relatively high concentrations shortly after infection and that PLY deficient S.pneumoniae strains are far less pathogenic then their PLY positive WT confounders. The in-vitro data presented here show that PLY induces a significant degree of complement activation, even when PLY was added at relatively low concentrations. Our findings are in strong support of the hypothesis that the ability of PLY to activate and consume complement may increase the pathogenicity of S.pneumoniae since it may protect the pneumococcus from opsonophagocytosis through host immune cells by directing complement deposition and opsonisation away from the bacterial surface. Increasing attention has been drawn to the wide occurrence of natural and man-made chemicals in the aquatic environment. Many chemicals can be bioaccumulated in the aquatic organisms and magnified in the food chains, thus threatening human health.Thus, pectin and hemicellulose are directly transported through the trans-Golgi network, while CESA proteins, involved in cellulose synthesis are cargoed to the plasma membrane, where cellulose synthesis occurs. Compartmentalisation in the cells of all organisms requires tight control and organisation. Spatial localisation of many macromolecules is controlled by RAB GTPases, which have been shown to regulate vesicle traffic to many compartments within the cell through their action as molecular AbMole Folic acid switches. In comparison with mammalian systems, Arabidopsis lacks some classes of RAB proteins, but others, most notably the RABA clade has expanded in number, diversity and perhaps roles and various members of the RABA clade have been implicated in trafficking to the cell wall. These genes are split into 8 clades which are further split into sub clades of varying size dependent on the clade. The RABA clade, in particular, shows a large expansion compared to the Rab11 genes of mammalian systems.