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:1980
卷号:77
期号:5
页码:2684-2687
DOI:10.1073/pnas.77.5.2684
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Three mutants of the crucifer Arabidopsis thaliana (Linnaeus) Heynhold were isolated that are completely lacking in activity catalyzed by serine-glyoxylate aminotransferase (EC 2.6.1.45 ), a peroxisomal enzyme involved in photorespiratory carbon metabolism. These mutants were viable and exhibited normal photosynthesis under conditions that suppressed photorespiration, but they were inviable and photosynthesized at greatly reduced rates under conditions that promoted photorespiration. Serine and glycine accumulated as end products of photosynthesis in the mutants, mostly at the expense of starch and sucrose. The mutants are allelic, and the segregation patterns of plant viability, photosynthetic activity, and enzyme activity in the F1 and F2 generations indicated that all the observed effects were caused by a single recessive nuclear mutation. This conclusion was confirmed by the isolation of seven revertants in which viability, photosynthetic capacity, and enzyme activity were simultaneously restored. Mutants of the type described here, in which photorespiration is changed from a merely wasteful process into one that is lethal, may permit the direct selection of secondary mutations that reduce photorespiration.