Shiga toxin: Difference between revisions

Shiga Toxin acts as an N-glycosidase, removing an adenine from the 60S ribosomal rRNA of a target cell leading to reduced protein synthesis.<ref name=Di>PMID: 21184769</ref>  The B subunit is necessary for binding to globo series glycolipid globotriaosylceramide (Gb3), a eukaryotic membrane receptor, where it is then endocytosed and proteolytically cleaved into two active A subunits and a B subunit.<ref name=Lenz>PMID: 2170899</ref>  Once the A subunit is transported to the cytosol it acts by depurinating the 28S ribosomal RNA which leads to inhibition of protein elongation and ultimately cellular apoptosis.  On the A subunit <scene name='Shiga_toxin_1/Active_site_zoomed_in/1'>Tyr77, Tyr114, Glu167, Arg170, and Trp203</scene> are all essential in glycosidic activity.<ref name=Di>PMID: 21184769</ref>