The V-ATPase A subunit gene (vma-1) from Giardia lamblia.

The sequence of the gene encoding the A subunit of the vacuolar type ATPase from Giardia lamblia is reported. Comparison of the encoded protein with the homologous subunits of eukaryotic and archaebacterial ATPases reveals high levels of similarity throughout the sequence (e.g., overall 49.1 and 44.6% identity to the homologous subunit from carrot and Halobacterium, respectively). An exception are three regions which are unique to the Giardia subunit. The largest of these regions contains motifs characteristic for eukaryotic spliceosomal introns; however, comparison to the cDNA shows that this region is also present in the mRNA.