title: Synthesis of chloroplast membrane lipids and chlorophyll in synchronous cultures of Chlamydomonas reinhardi.
abstract: Chloroplast membrane lipid synthesis has been studied in synchronously growing cultures of Chlamydomonas reinhardi. The synthesis of sulfolipid and phospholipid were measured by incorporation of 35SO4(2-) and 32PO4(3-) during a 1-h pulse. Galactolipid synthesis was measured by H14CO3- incorporation into lipid fractions separated by thin layer chromatography. Lipid synthesis occurs principally during the light portion of the synchronous cycle. Phosphatidylglycerol is synthesized between 3-4 h in the light and sulfolipid is labeled between 7-9 h in the light. Galactolipid synthesis appears to reach maximal rates shortly after the lights go on and again at 7 h. Chlorophyll reaches maximal rates of synthesis after 7 h. These lipids are made and inserted into the chloroplast membrane prior to major increases in photosynthetic capacity. Our results also show that chloroplast membrane lipids are synthesized in a sequential or multistep process.
mesh_terms: D002455:Cell Division; D002462:Cell Membrane / Q000378:metabolism; D002696:Chlamydomonas / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism*; D006017:Glycolipids / Q000096:biosynthesis; D007700:Kinetics; D008563:Membrane Lipids / Q000096:biosynthesis*; D010743:Phospholipids / Q000096:biosynthesis
chemical_list: D006017:Glycolipids; D008563:Membrane Lipids; D010743:Phospholipids; D002734:Chlorophyll