Potential DNA binding and nuclease functions of ComEC domains characterized in silico.

Bacterial competence, which can be natural or induced, allows the uptake of exogenous double stranded DNA (dsDNA) into a competent bacterium. This process is known as transformation. A multiprotein assembly binds and processes the dsDNA to import one strand and degrade another yet the underlying molecular mechanisms are relatively poorly understood.

The malaria parasite cyclic GMP-dependent protein kinase plays a central role in blood-stage schizogony.

A role for the Plasmodium falciparum cyclic GMP (cGMP)-dependent protein kinase (PfPKG) in gametogenesis in the malaria parasite was elucidated previously. In the present study we examined the role of PfPKG in the asexual blood-stage of the parasite life cycle, the stage that causes malaria pathology. A specific PKG inhibitor (compound 1, a trisubstituted pyrrole) prevented the progression of P.

The motor complex of Plasmodium falciparum: phosphorylation by a calcium-dependent protein kinase.

Calcium-dependent protein kinases (CDPKs) of Apicomplexan parasites are crucial for the survival of the parasite throughout its life cycle. CDPK1 is expressed in the asexual blood stages of the parasite, particularly late stage schizonts. We have identified two substrates of Plasmodium falciparum CDPK1: myosin A tail domain-interacting protein (MTIP) and glideosome-associated protein 45 (GAP45), both of which are components of the motor complex that generates the force required by the parasite to actively invade host cells.

Extensive proteolytic processing of the malaria parasite merozoite surface protein 7 during biosynthesis and parasite release from erythrocytes.

In Plasmodium falciparum, merozoite surface protein 7 (MSP7) was originally identified as a 22kDa protein on the merozoite surface and associated with the MSP1 complex shed during erythrocyte invasion. MSP7 is synthesised in schizonts as a 351-amino acid precursor that undergoes proteolytic processing. During biosynthesis the MSP1 and MSP7 precursors form a complex that is targeted to the surface of developing merozoites.

Characterisation of the rhoph2 gene of Plasmodium falciparum and Plasmodium yoelii.

The high molecular mass protein complex (RhopH) in the rhoptries of the malaria parasite consists of three distinct polypeptides with estimated sizes in Plasmodium falciparum of 155kDa (PfRhopH1), 140kDa (PfRhopH2) and 110kDa (PfRhopH3). Using a number of reagents, including a new mAb 4E10 that is specific for the PfRhopH complex, it was shown that the RhopH complex is synthesised during schizogony and transferred intact to the ring stage in newly invaded erythrocytes. The genes encoding RhopH1 and RhopH3 have already been identified and characterised in both P.

Variation in the expression of a Plasmodium falciparum protein family implicated in erythrocyte invasion.

The PfRH protein family of Plasmodium falciparum is implicated in erythrocyte invasion. Here we report variations in the sequence, transcription, and protein expression of four different members of this family in three parasite lines, 3D7, T996, and FCB1. There are sequence polymorphisms in PfRH1, PfRH2a, PfRH2b, and PfRH3, ranging from variations across repeat regions to a 585-bp deletion in the 3' end of PfRH2b in T996.