Exploration of the Binding Site of Arachidonic Acid in gp63 of and in Orthologous Proteins in Clinically Important Parasites.

Recently, we published that the monoclonal antibody (D12 mAb) recognizes gp63 of , and it is responsible for COX activity. This D12 mAb exhibited cross-reactivity with , , , and . COX activity assays performed in these parasites suggested the potential presence of such enzymatic activity.

Transcriptional analysis in bacteriophage Fc02 of revealed two overlapping genes with exclusion activity.

Little is known about the gene expression program during the transition from lysogenic to lytic cycles of temperate bacteriophages in . To investigate this issue, we developed a thermo-sensitive repressor mutant in a lysogen and analyzed the phage transcriptional program by strand-specific RNA-Seq before and after thermo-induction. As expected, the repressor gene located on the phage DNA forward strand is transcribed in the lysogen at the permissive temperature of 30°C.

Efficient expression of gene variants that harbour AGA codons next to the initiation codon.

In an effort to improve the knowledge about the rules which direct the effect of the early ORF sequences on translation efficiency, we have analyzed the effect of pairs of the six arginine codons at the second and third positions on the expression of lacZ variants. Whereas the pairs of identical AGA or AGG codons were favorable for the gene expression, identical pairs of each of the four CGN codons were very inefficient. This result was unexpected because tandems of AGA or AGG codons located in more internal gene positions provoke deficient expression whilst internally located CGU and CGC are the most abundant and efficiently translated arginine codons.

Ribosome stalling and peptidyl-tRNA drop-off during translational delay at AGA codons.

Minigenes encoding the peptide Met-Arg-Arg have been used to study the mechanism of toxicity of AGA codons proximal to the start codon or prior to the termination codon in bacteria. The codon sequences of the 'mini-ORFs' employed were initiator, combinations of AGA and CGA, and terminator. Both, AGA and CGA are low-usage Arg codons in ORFs of Escherichia coli but, whilst AGA is translated by the scarce tRNA(Arg4), CGA is recognized by the abundant tRNA(Arg2).