Excretion of nitrite during nitrate assimilation by phytoplankton is examined in relation to estimates of new production. Evidence from the literature indicates that nitrite excretion is exhibited by a wide variety of phytoplankton species in cultures and can represent up to 25, 45 and 50"0 of nitrate uptake in Thalassiosira pseudonana, Prorocentrum minimum and Skeletonema costa turn respective...

Maintaining cell volume is critical for cellular function yet shift in cell volume is a prerequisite for mitosis and apoptosis. The ubiquitously and evolutionary conserved serine/threonine kinase CK2 promotes cell survival and suppresses apoptosis. The present review describes how mammalian cells regulate the cellular content of the major cellular organic osmolyte, taurine with emphasis on CK2 ...