Metabolic changes during development of Phytophthora palmivora examined by gas chromatography/mass spectrometry

Metabolic profiles from four stages of differentiation of the fungus Phytophthora palmivora were obtained by gas chromatography/mass spectrometry. The profiles showed the presence of sterols in the asexual reproduction stage of the organism, and confirmed their virtual absence from the mycelial stages. The zoospore stage was characterized by the presence of polyunsaturated fatty acids of C20 and C22 chain length. The transition from zoospore to cyst was also marked by the appearance of disaccharides and by a decrease in the amount of phosphate present. There were also distinctive shifts in the proportions and the total amounts of amino acids present, with gamma-aminobutyrate and alanine increasing as germination took place. These distinctive profiles identify some of the metabolic changes which accompany differentiation in this fungus.