Linked expressions of nap and nos genes in a Bradyrhizobium japonicum mutant with increased N(2)O reductase activity.
نویسندگان
چکیده
To understand the mechanisms underlying the increased N2O reductase activity in the Bradyrhizobium japonicum 5M09 mutant from enrichment culture under N2O respiration, we analyzed the expression of genes encoding denitrification reductases and regulators. Our results suggest a common regulation of nap (encoding periplasmic nitrate reductase) and nos (encoding N2O reductase).
منابع مشابه
Linked expression of nap and nos genes in a Bradyrhizobium japonicum 1 mutant with increased N 2 O reductase activity
13 To understand the mechanisms underlying the increased N2O reductase activity in the 14 Bradyrhizobium japonicum 5M09 mutant from enrichment culture under N2O respiration, we 15 analyzed the expression of genes encoding denitrification reductases and regulators. Our 16 results suggest a common regulation of nap (encoding periplasmic nitrate reductase) and nos 17 (encoding N2O reductase). 18
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Denitrification is an alternative form of respiration in which bacteria sequentially reduce nitrate or nitrite to nitrogen gas by the intermediates nitric oxide and nitrous oxide when oxygen concentrations are limiting. In Bradyrhizobium japonicum, the N(2)-fixing microsymbiont of soya beans, denitrification depends on the napEDABC, nirK, norCBQD, and nosRZDFYLX gene clusters encoding nitrate-,...
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ورودعنوان ژورنال:
- Applied and environmental microbiology
دوره 79 13 شماره
صفحات -
تاریخ انتشار 2013