 As such, Chloroviruses are an important mechanism to the termination of algal blooms and play a vital role in the supply of nutrients to the water column (See "Ecology" section for more information).Chloroviruses are also able to change the wall structure of infected cells.Some chloroviruses contain chitin synthase (CHS) genes while some others contain hyaluronan synthase (HAS) genes, respectively triggering the formation of chitin sensitive fibres or hyaluronan sensitive fibres.