Complete Genome Sequence and Lytic Phase Transcription Profile of a Coccolithovirus

Abstract

The genus Coccolithovirus is a recently discovered group of viruses that infect the globally important marine calcifying microalga Emiliania huxleyi . Among the 472 predicted genes of the 407,339–base pair genome are a variety of unexpected genes, most notably those involved in biosynthesis of ceramide, a sphingolipid known to induce apoptosis. Uniquely for algal viruses, it also contains six RNA polymerase subunits and a novel promoter, suggesting this virus encodes its own transcription machinery. Microarray transcriptomic analysis reveals that 65% of the predicted virus-encoded genes are expressed during lytic infection of E. huxleyi .