Details

Autor(en) / Beteiligte

• Anderson, L.W.J
• Sweeney, B.M

Titel

Diel changes in sedimentation characteristics of Ditylum brightwelli: changes in cellular lipid and effects of respiratory inhibitors and ion transport modifiers

Ist Teil von

• Limnology and oceanography, 1977-01, Vol.22 (3), p.539-552

Ort / Verlag

American Society of Limnology and Oceanography

Erscheinungsjahr

1977

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Temperature-controlled seawater columns were used to investigate settling rates of Ditylum brightwelli grown on light-dark schedules. Ficoll density gradient centrifugation was used to examine the effects of KCN, DNP, and the ion-transport modifiers valinomycin, nigericin, and gramicidin on sedimentation characteristics in the gradients. Sedimentation rates were minimal at the end of the dark period (L8:D16; L12:D12) and maximal during the latter half of the light period. The presence of maximum lipid per cell during the period of maximum settling rate argues against a fat-mediated buoyancy mechanism. Cells exposed to respiratory inhibitors, valinomycin, or nigericin sedimented more rapidly than did control cells; gramicidin appeared to decrease sedimentation rate. The effectiveness of these agents suggests that settling rate in this diatom is controlled through ion regulation.