Protein O-Fucosyltransferase 2 Is Not Essential for Plasmodium berghei Development

Thrombospondin type I repeat (TSR) domains are commonly O-fucosylated by protein O-fucosyltransferase 2 (PoFUT2), and this modification is required for optimal folding and secretion of TSR-containing proteins. The human malaria parasite Plasmodium falciparum expresses proteins containing TSR domains, such as the thrombospondin-related anonymous protein (TRAP) and circumsporozoite surface protein (CSP), which are O-fucosylated. TRAP and CSP are present on the surface of sporozoites and play essential roles in mosquito and human host invasion processes during the transmission stages. Here, we have generated PoFUT2 null-mutant P. falciparum and Plasmodium berghei (rodent) malaria parasites and, by phenotyping them throughout their complete life cycle, we show that PoFUT2 disruption does not affect the growth through the mosquito stages for both species. However, contrary to what has been described previously by others, P. berghei PoFUT2 null mutant sporozoites showed no deleterious motility phenotypes and successfully established blood stage infection in mice. This unexpected result indicates that the importance of O-fucosylation of TSR domains may differ between human and RODENT malaria parasites; complicating our understanding of glycosylation modifications in malaria biology

Overview of the FTU results

Since the 2018 IAEA FEC Conference, FTU operations have been devoted to several experiments covering a large range of topics, from the investigation of the behaviour of a liquid tin limiter to the runaway electrons mitigation and control and to the stabilization of tearing modes by electron cyclotron heating and by pellet injection. Other experiments have involved the spectroscopy of heavy metal ions, the electron density peaking in helium doped plasmas, the electron cyclotron assisted start-up and the electron temperature measurements in high temperature plasmas. The effectiveness of the laser induced breakdown spectroscopy system has been demonstrated and the new capabilities of the runaway electron imaging spectrometry system for in-flight runaways studies have been explored. Finally, a high resolution saddle coil array for MHD analysis and UV and SXR diamond detectors have been successfully tested on different plasma scenarios

Overview of the FTU results

Since the 2016 IAEA Fusion Energy Conference, FTU operations have been mainly devoted to experiments on runaway electrons and investigations into a tin liquid limiter; other experiments have involved studies of elongated plasmas and dust. The tearing mode onset in the high density regime has been studied by means of the linear resistive code MARS, and the highly collisional regimes have been investigated. New diagnostics, such as a runaway electron imaging spectroscopy system for in-flight runaway studies and a triple Cherenkov probe for the measurement of escaping electrons, have been successfully installed and tested, and new capabilities of the collective Thomson scattering and the laser induced breakdown spectroscopy diagnostics have been explored

Reactivity of Cationic Molybdenum(II) Complexes. Part 1. Hydride Reduction of the 18 Electron Complexes [Mo(CO)3(eta-C5Me5)] + [L=PPh3 or P(OMe)3] and Isolation of the Thermally Stable Formil Complex cis-[Mo(CO)2(eta-C5Me5){P(OMe)3}(CHO)] Crystal Structure of [Mo(CO)(eta-C5Me5)(PPh3)]BF4.0.5MeOH

The compound [Mo(CO)3(η-C5Me5)]BF4 reacts with π acids, L [L = PPh3, P(OMe)3, CO, or p-MeC6H4NC], giving the 18 electron cations [Mo(CO)3(η-C5Me5)L]+. The complex [Mo(CO)3(η-C5Me5)(PPh3)]BF4 (1) has been characterized by a single-crystal X-ray diffraction study. The reaction of (1) with one equivalent of Na[BH4] gives the neutral metal formyl complex [Mo(CO)2(η-C5Me5)(PPh3)(CHO)], (2), which, in solution, converts to [MoH(CO)3(η-C5Me5)] above –40 °C. If [Mo(CO)3(η-C5Me5){P(OMe)3}]BF4, (3), is used instead of (1), the reduction in methanol solution with Na[BH4] allows isolation of the thermally stable cis-[Mo(CO)2(η-C5Me5){P(OMe)3}(CHO)], (4). Thermal decomposition of (4) in methanol solution at room temperature is slow and gives cis-[MoH(CO)2(η-C5Me5){P(OMe)3}]. This result emphasizes that the great difference observed in the thermal stability of complexes (2) and (4) is attributable to different decomposition pathways