[3H]acetate labeling showed fatty acids are synthesized in the cytosol, with little incorporation in chloroplasts, consistent with a Type I FAS system. However, although 29 sequences

in a K. brevis expressed sequence tag database have similarity (BLASTx e-value <10−10) to PKSs, no transcripts for either Type I (cytosolic) or Type II (chloroplast) FAS are present. Further characterization of the FAS complexes may help to elucidate the functions of the Small molecule library PKS enzymes identified in dinoflagellates. “
“Prymnesium parvum blooms have become more frequent in the south-central United States, leading to significant ecological and economic impacts. Allelopathic effects from cyanobacteria were suggested as a mechanism that might limit the development of P. parvum blooms. This research focused on the effects of cultured cyanobacteria, Anabaena sp., on P. parvum. Over a 6-d period, daily additions of filtrate from the senescent Anabaena culture were made to P. parvum cultures growing in log phase. All treatments, including several types of controls, showed reductions in P. parvum biomass over the course of the experiment, but the treatments receiving Anabaena filtrate were reduced to a lesser degree, suggesting

that filtrate from the senescent cyanobacteria culture was beneficial to P. parvum in some way. This unexpected outcome may have resulted from stimulation of heterotrophic bacteria by the addition of Anabaena filtrate, which likely contained exudates rich in dissolved organic carbon compounds. P. parvum selleck kinase inhibitor was then able to supplement its nutritional requirements for growth by feeding on the elevated bacteria population. These findings coupled Methocarbamol to previous observations suggest that interactions between cyanobacteria and P. parvum in natural environments are complex, where both allelopathic and growth-stimulating interactions are possible. “
“The red seaweed Gracilariopsis is an important

crop extensively cultivated in China for high-quality raw agar. In the cultivation site at Nanao Island, Shantou, China, G. lemaneiformis experiences high variability in environmental conditions like seawater temperature. In this study, G. lemaneiformis was cultured at 12, 19, or 26°C for 3 weeks, to examine its photosynthetic acclimation to changing temperature. Growth rates were highest in G. lemaneiformis thalli grown at 19°C, and were reduced with either decreased or increased temperature. The irradiance-saturated rate of photosynthesis (Pmax) decreased with decreasing temperature, but increased significantly with prolonged cultivation at lower temperatures, indicating the potential for photosynthesis acclimation to lower temperature. Moreover, Pmax increased with increasing temperature (~30 μmol O2 · g−1FW · h−1 at 12°C to 70 μmol O2 · g−1FW · h−1 at 26°C).