Figure 1.

Winkler test with mutant strains producing low amounts of oxygen. Wild types CC-425 and CC-124 served as positive controls, the Rubisco-deficient strain CC-2803 as a negative control. A) Detail of a 48-well plate with 1 ml algal cultures before (left) and after MnCl₂, KI/NaOH, H₃PO₄ and starch addition (right). Four independent test wells are shown for each strain B) Titration volume needed for each strain to reach the titration point. Values represent means ± standard deviation (n = 8).