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In the blood stream the merozoite is the invasive form of the malaria parasite that must enter a new erythrocyte. Merozoites lack structure for locomotion such as cilia and flagella, but use an actomyosin motor complex that provides the force to drive them into the cell. This molecular motor is located at the pellicle membrane of the parasite. The motor protein complex or glideosome includes a class XIV myosin heavy chain (MyoA), Myosin Tail Interacting Protein (MTIP) and two anchoring proteins known as Glideosome Associated Protein 45 (GAP45) and GAP50. A ternary complex of MyoA-MTIP-GAP45 is first formed and this later associates with GAP50. Using a GFP-tagged MyoA transgenic parasite line the expression of MyoA was examined in both Plasmodium falciparum and P. knowlesi. The protein was expressed at the periphery of the parasite and associates with MTIP, GAP45 and GAP50. In time course studies it was shown that recruitment of GAP50 to the complex occurs late relative to the onset of GAP50 synthesis, likely reflecting a role for GAP50 in cellular processes prior to host cell invasion. A second class XIV myosin, Myosin B (MyoB) was also tagged with GFP in a transgenic parasite line. Whilst the timing of MyoB expression followed that of MyoA, with clearly detectable protein in segmenting schizonts at 40 hours post invasion, MyoB did not associates with MyoA or any of the other invasion complex proteins. The localisation of MyoB-GFP in P. falciparum was at the apical end of the merozoite, in front of other apical organelle markers such as Rhoptry neck protein 4 (RON4). During erythrocyte invasion, MyoB -GFP remained in the same location, whilst RON4 moved out onto the parasite surface as part of the moving junction and migrated to the rear of the parasite. Although the exact role of MyoB is unknown, it is suggested that it may be involved in the invasion process but within its own protein complex that is distinct from the glideosome.

The physical and chemical nature of the soils that occur in the State of Hawaii are unique as compared to soils found in other parts of the world. The soils of the wet area of the Hilo-Hamakua coast on the Island of Hawaii, maintain a moisture level around 300% for the most part .of the year. These soils which developed from volcanic ash and under high rainfall are very active in ion fixation. Their mineral composition consists mainly of amorphous colloidal hydrated oxides of aluminum and iron. Allophane and gibbsite are found in considerable quantities (4,41), while magnetite, maghemite, and quartz are a minor portion of the constituents of these soils. The fixation of ammonium in these and other Hawaiian soils has been investigated very briefly, and all reported studies were quantitative in nature. Due to the developments in technology and the availability of modern equipment, like the X-ray diffractometer, qualitative studies of NH4 fixation in Hawaiian soils became possible. The major interest of this study was to determine the nature of NH4 fixation in Hawaiian soils, with emphasis on the soils that are predominantly amorphous in nature. The soils were kept under field conditions with the exception of the additions of NH4 carriers. No quantitative analysis was attempted due to the complexities and the unlimited sources of error that could result when tremendously large quantities of NH4 carriers were added to the soil. The very high concentration of NH4 carriers that were added to the soil was selected to simulate conditions that might prevail in the field when the fertilizer is applied in a band. When a solid NH4 fertilizer is added to the soil, the area surrounding the fertilizer granule will have a very high concentration of NH4 , and that is where any initial reaction between the NH4 carrier and the soil might occur.