Lysozyme from the gut of the soft tick Ornithodoros moubata: the sequence, phylogeny and post-feeding regulation

摘要: Sequence of a tick gut lysozyme (TGL) from the soft Ornithodoros moubata was determined by cloning and sequencing overlapping polymerase chain reaction (PCR) RACE PCR products. It is first sequence representing subphylum Chelicerata. The resulting open reading frame codes for putative signal peptide 22 amino-acid residues mature protein composed 124 amino-acids. Calculated mass 14037.75 Da theoretical isoelectric point 8.16. phylogenetic analysis revealed that TGL belongs to c-type lysozymes. forms distinct monophyletic group together with multiple lysozyme-like sequences found in gene products agCP6542 Anopheles gambiae strain PEST CG8492-PA Drosophila melanogaster. This referred as an H-branch due unique histidine residue at position 52 which replaces highly conserved tyrosine present vast majority seems be interesting case features lysozymes anti-bacterial digestive function are combined. Semi-quantitative RT-PCR Northern blotting demonstrated strongly up-regulated transcriptional level after bloodmeal. maximum mRNA detected 16 h post bloodmeal message remained stable 5 days then it slowly dropped down non-fed ticks within 2 weeks.