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：8
页码：2340-2344
DOI：10.1073/pnas.70.8.2340
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Saccharomyces cerevisiae can degrade allantoin in five steps to glyoxylate, ammonia, and "CO2." We previously demonstrated that synthesis of the urea carboxylase-allophanate hydrolase multienzyme complex is contingent upon the presence of allophanic acid, the product of the urea carboxylase reaction. Since these enzymes catalyze the last two reactions of allantoin degradation, experiments were performed to establish whether or not the presence of allophanic acid was required for synthesis of any other enzymes participating in this degradative pathway. The data presented here indicate that allophanic acid is required for synthesis of all enzymes participating in allantoin degradation. This conclusion is based upon the observation that: (i) wild-type strains produced a large amount of allantoinase upon addition of allantoin, allantoate, ureidoglycolate, or urea to the medium, (ii) no increase in activity was observed unless the added compound could be metabolized to allophanate, (iii) strains lacking allophanate hydrolase contained large amounts of allantoinase even in the absence of added urea, and (iv) the urea analogue, formamide, was capable of inducing allantoinase synthesis in wild-type strains but would not serve this function in a strain lacking urea carboxylase.
