We studied the effects of Heterosigma akashiwo, a harmful algal species, in the diet of juvenile Manila clams (Ruditapes philippinarum), because it often blooms in coastal waters where aquaculture of the clams is carried out. Weight of soft tissue of clams increased when they were fed H. akashiwo added at 8,000 cells mL-1, with weight growth about 8% higher than that of clams fed only Chaetocer...

The growth characteristics of Heterosigma akashiwo virus clone 01 (HaV01) were examined by performing a one-step growth experiment. The virus had a latent period of 30 to 33 h and a burst size of 7.7 x 10(2) lysis-causing units in an infected cell. Transmission electron microscopy showed that the virus particles formed on the peripheries of viroplasms, as observed in a natural H. akashiwo cell....

The formation of toxic surface blooms of the motile raphidophyte Heterosigma akashiwo often occurs too quickly to be attributed to cell reproduction. Rapid appearance of surface blooms is more consistent with the hypothesis that a dispersed cell population aggregates at the surface due to a combination of physical factors and swimming behavior. Because of the frequent association of Heterosigma...

Heterosigma akashiwo is an excellent candidate for growth on industrial emissions since this alga has the ability to metabolize gaseous nitric oxide (NO) into cellular nitrogen via a novel chimeric protein (NR2-2/2HbN) and also tolerates wide fluctuations in temperature, salinity, and nutrient conditions. Here, we evaluated biomass productivity and composition, photosynthetic efficiency, and ex...

Six blooms of Heterosigma akashiwo (Raphidophyceae) were observed from March 2007 through March 2008 in the Rodrigo de Freitas Lagoon, a semi-confined eutrophic system located in Rio de Janeiro state, southeast Brazil. Vegetative cells of H. akashiwo analysed by optical and electron microscopy showed morphology as described in the literature. The blooms (2.8 × 10(4) to 4 × 10(8) cell.L(-1)) wer...

During a bacterial survey of the Huon Estuary in southern Tasmania, Australia, we isolated a yellow-pigmented Pseudoalteromonas strain (class Proteobacteria, gamma subdivision), designated strain Y, that had potent algicidal effects on harmful algal bloom species. This organism was identified by 16S rRNA sequencing as a strain with close affinities to Pseudoalteromonas peptidysin. This bacteriu...

We studied the possible role that marine microalgae may play during the outbreaks of WSS (white spot syndrome). In order to elucidate the possibility of marine microalgae carrying WSSV (white spot syndrome virus), six marine microalgae (Isochrysis galbana, Skeletonema costatum, Chlorella sp., Heterosigma akashiwo, Scrippsiella trochoidea, Dunaliella salina) were co-cultured with adult Marsupena...

" Bacterial chemotaxis towards the extracellular products of the toxic phytoplankton Heterosigma akashiwo. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters.

Cell motility may facilitate the formation of harmful algal blooms (HABs) by enabling algal cells to swim to favorable microenvironments that support explosive growth. Motility also augments the formation of algal cell aggregations that are often associated with ecological and economic consequence. In this study, we used computerized video analysis to quantify cell-level swimming characteristic...