期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1973
卷号：70
期号：10
页码：2727-2731
DOI：10.1073/pnas.70.10.2727
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Cellular differentiation can be observed in certain filamentous blue-green algae after transfer of the cells from medium containing NH4+ or NO3- to nitrogen-free medium. The appearance of differentiated cells (heterocysts) is accompanied by an increase in the activity of nitrogenase, an enzyme complex that reduces N2 to NH3. We have separated vegetative cells from heterocysts in differentiated filaments of Nostoc muscorum, and analyzed their proteins by polyacrylamide-gel electrophoresis. The pattern of incorporation of 35SO4- into proteins of the two cell types during differentiation indicates that the increase in nitrogenase activity is due to the de novo synthesis of nitrogenase proteins predominantly, if not exclusively, in heterocysts.
