[Sick from algae?].

Microalgal photosynthesis can be predicted using empirical allometric or mechanistic bio-optic models. These two descriptions are usually considered independently. We compare the size scaling of photosynthesis predicted by these two models. Size scaling exponents for phytoplankton often deviate from the allometric 3/4 rule. This may be because the allometric model does not account for the size dependence of light absorption and its effect on the size scaling of photosynthesis. In contrast to the allometric model and experimental data, the bio-optic model predicts photosynthesis should be independent of cell size when intracellular pigment concentrations are low or inversely related to cell diameter. A composite of the allometric and bio-optic models is described and compared to laboratory data of light-limited nutrient-saturated diatom photosynthesis. The allo-bio-optic model provides a mechanistic explanation for the anomalous size scaling found in laboratory and field studies of microalgal photosynthesis and growth.

Eukaryota↗

PubMed2000

Microbial genomes--the untapped resource.

Although the 1990s have ushered in the genome, they have also exposed our limitations for deriving structural and functional information. In parallel, molecular phylogeny has demonstrated that the majority of microbial genomes are currently inaccessible. Key objectives for the next century are the development of techniques for accessing 'unculturable' genomes, exploiting their biotechnologically valuable genes and products, and linking genome-sequence data to molecular structure and function.

Eukaryota↗