The high affinity phosphate transport system (pst) is crucial for phosphate uptake in oligotrophic environments. Cuatro Cienegas Basin (CCB) has extremely low P levels and its endemic Bacillus are closely related to oligotrophic marine Firmicutes. Thus, we expected the pst operon of CCB to share the same evolutionary history and protein similarity to marine Firmicutes. Orthologs of the pst oper...

The present water quality conditions in the Seto Inland Sea of Japan are described along with an historical background before and after the measures taken to reduce eutrophication. The directive to reduce phosphorus discharge into this area was very effective, reducing the number of red tides from about 300 cases per year at their peak in 1976 to the recent level of about 100 cases per year, in...

Introduction Conclusions References

Introduction Conclusions References

Here we investigate the allocation of resources between growth and reproduction by surveying the dynamics of natural populations of the aquatic detritivorous mudsnail Potamopyrgus antipodarum from two interconnected lakes that differ in trophic state. The size distributions and reproductive output of the snail populations was analyzed monthly by field surveys spanning 3 years, and in a controll...

Molecular evidence for proteorhodopsin- and bacteriochlorophyll-based photoheterotrophy is widespread in oligotrophic marine microbial community metagenomes, and has been implicated in light-enhanced growth rates, substrate uptake rates, and anapleurotic carbon fixation, thus complicating the web of interactions within the 'microbial loop.' We quantified photoheterotrophic metabolism of the oxi...

The North Atlantic Subtropical Gyre (NASTG) has experienced the fastest expansion of oligotrophic waters worldwide in response to ocean warming. We study trophic regime changes NASTG by using 21 years (1998–2018) satellite chlorophyll-a (CHL) data, complemented with other variables such as Sea Surface Temperature, optical backscatter coefficients (bbp), Secchi disk (zSD), and Mixed Layer Depth....

The diel rate of microbial nucleic acid synthesis and the concentration of particulate DNA were measured at various locations in the oligotrophic Pacific Ocean. Net synthesis of RNA and DNA was observed over 24-h periods at all locations investigated, but the actual rate sometimes varied with time of day. It is concluded that whenever possible, daily rates of synthesis should be determined from...