Sulfate uptake by the green alga Chlamydomonas reinhardtii is a light-
dependent saturable process with maximal rate at 0.3 mM sulfate. Kinet
ically, the transport appears to be multifasic with at least two Km va
lues about 10 and 40 muM. It can be efficiently inhibited by sulfite a
nd chromate. Sulfate uptake was significantly enhanced in S-starved ce
lls, the initial uptake rate being doubled after 30 min under S-depriv
ed conditions.