Phylogenetic Distribution of CMP-Neu5Ac Hydroxylase (CMAH), the Enzyme Synthetizing the Proinflammatory Human Xenoantigen Neu5Gc

Peri, Sateesh; Kulkarni, Asmita; Feyertag, Felix; Berninsone, Patricia M; Alvarez-Ponce, David

We found putatively functional copies in all ten echinoderm species studied. Acanthaster planci (crown-of-thorns starfish) has two copies: one putatively functional and another putatively inactivated due to a premature stop codon in coding exon 10 (table 2). Our observations are consistent with prior works that have reported the presence of the CMAH enzyme, its encoding gene, or Neu5Gc in all echinoderms studied so far. The enzyme was purified from gonads of Asterias rubens (common star fish), Ctenodiscus crispatus (mud star), Strongylocentrotus pallidus (pale sea urchin), and a species of Holothuria (a sea cucumber) (Gollub and Shaw 2003) . The Asterias rubens CMAH cDNA was subsequently cloned and sequenced (Martensen et al. 2001) , revealing a highly conserved CMAH coding sequence. Neu5Gc was detected in whole body extracts of Ophioderma brevispina (a brittle star), Nemaster rubiginosa (sea lily), and Sclerodactyla briareus (a sea cucumber) (Warren 1963; Sumi et al. 2001 ) and in the egg jelly coat of Paracentrotus lividus (a sea urchin) (Yes¸ilyurt et al. 2015) .