Formation and emission of monohalomethanes from marine algae

Methyl bromide (5.9 ng g wet algae −1 hr −1 ) and methyl iodide (6.9 ng g wet algae −1 hr −1 ) were produced by the microalga Pavlova gyrans , and methyl iodide (21.4 ng g wet algae hr −1 for Papenfusiella kuromo and 4 ng g wet algae hr −1 for Sargassum horneri ) and a trace amount of methyl bromide by macroalgae. Methyl halides were synthesized from S- adenosyl- l -methionine (SAM) in cell-free extracts of P. gyrans, P. Kuromo and S. horneri . This mechanism corresponded to the emission of methyl halides from the three algae in vivo . We have studied the optimal pH, and halide ion and methyl donor specificities of the novel enzyme from P. gyrans .