Oxygen-regulated steps in the Rhodobacter capsulatus tetrapyrrole biosynthetic pathway.
نویسنده
چکیده
The effect of exogenous aminolevulinate and porphobilinogen on protoporphyrin accumulation in Rhodobacter capsulatus was measured. Oxygen inhibited protoporphyrin accumulation in strain AJB456, a bchH mutant, even in the presence of exogenous aminolevulinate, suggesting that some step in the formation of protoporphyrin from aminolevulinate is regulated by oxygen. In contrast, in the presence of exogenous porphobilinogen, oxygen did not inhibit protoporphyrin accumulation. The results presented in this study indicate that oxygen regulates the formation of porphobilinogen from aminolevulinate.
منابع مشابه
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عنوان ژورنال:
- Journal of bacteriology
دوره 174 16 شماره
صفحات -
تاریخ انتشار 1992