18 research outputs found
Expression of a malarial Hsp70 improves defects in chaperone-dependent activities in ssa1 mutant yeast
Plasmodium falciparum causes the most virulent form of malaria and encodes a large number of molecular chaperones. Because the parasite encounters radically different environments during its lifecycle, many members of this chaperone ensemble may be essential for P. falciparum survival. Therefore, Plasmodium chaperones represent novel therapeutic targets, but to establish the mechanism of action of any developed therapeutics, it is critical to ascertain the functions of these chaperones. To this end, we report the development of a yeast expression system for PfHsp70-1, a P. falciparum cytoplasmic chaperone. We found that PfHsp70-1 repairs mutant growth phenotypes in yeast strains lacking the two primary cytosolic Hsp70s, SSA1 and SSA2, and in strains harboring a temperature sensitive SSA1 allele. PfHsp70-1 also supported chaperone-dependent processes such as protein translocation and ER associated degradation, and ameliorated the toxic effects of oxidative stress. By introducing engineered forms of PfHsp70-1 into the mutant strains, we discovered that rescue requires PfHsp70-1 ATPase activity. Together, we conclude that yeast can be co-opted to rapidly uncover specific cellular activities mediated by malarial chaperones. © 2011 Bell et al
Bioprospecting of strains of Streptococcus thermophilus from Indian fermented milk products for folate production
Henoch scholein purpura presenting as distal ileitis in a postmenopausal woman: A rare case report
Henoch Schonlein purpura (HSP) is a small vessel vasculitis leading to deposition of immune IgA complexes. It presents with a tetrad of symptoms, including a purpuric rash occurring on the lower extremities, gastro intestinal involvement, renal involvement and arthritis. HSP is self limited and primarily affects children .The etiology is unknown. Treatment is mainly supportive therapy with analgesics and in severe cases, steroids are used. Here we report a rare case of Henoch Scholein purpura in a postmenopausal woman presenting as acute distal ileitis
Harden up: metal acquisition in the weaponized ovipositors of aculeate hymenoptera
The use of metal ions to harden the tips and edges of ovipositors is known to occur in many hymenopteran species. However, species using the ovipositor for delivery of venom, which occurs in the aculeate hymenoptera (stinging wasps, ants, and bees) remains uninvestigated. In this study, scanning electron microscopy coupled with energy-dispersive X-ray analysis was used to investigate the morphology and metal compositional differences among aculeate aculei. We show that aculeate aculei have a wide diversity of morphological adaptations relating to their lifestyle. We also demonstrate that metals are present in the aculei of all families of aculeate studied. The presence of metals is non-uniform and concentrated in the distal region of the stinger, especially along the longitudinal edges. This study is the first comparative investigation to document metal accumulation in aculeate aculei