CO2 fixation by a high temperature high CO2 tolerant Chlorella sp.

A new type of Chlorella sp. with a high efficiency for fixing CO2 at a high temperature and in a high CO2 concentration was isolated after the large-s cale screening of microalgae in various natural environments. A low chlorop hyll- content mutant of the Chlorella sp. showed a high performance of ligh t-utilization efficiency in the high-cell-density cultures with high illumi nation. We also cloned a desaturase gene of the alga, as a first step in th e molecular breeding of green algae.