A wide range of Bacteria and Archaea sense cellular 2-oxoglutarate (2OG) as an indicator of nitrogen limitation. 2OG sensor proteins are varied, but most of those studied belong to the PII superfamily. Within the PII superfamily, GlnB and GlnK represent a widespread family of homotrimeric proteins (GlnB-K) that bind and respond to 2OG and ATP. In some bacterial phyla, GlnB-K proteins are covalently modified, depending on enzymes that sense cellular glutamine as an indicator of nitrogen sufficiency. GlnB-K proteins are central clearing houses of nitrogen information and bind and modulate a variety of nitrogen assimilation regulators and enzymes. NifI(1) and NifI(2) comprise a second widespread family of PII proteins (NifI) that are heteromultimeric, respond to 2OG and ATP, and bind and regulate dinitrogenase in Euryarchaeota and many Bacteria.

中文翻译：

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细菌和古细菌中的氮调节。

广泛的细菌和古细菌将细胞2-氧戊二酸酯（2OG）视为氮限制的指标。2OG传感器蛋白是多种多样的，但是研究的大多数蛋白都属于PII超家族。在PII超家族中，GlnB和GlnK代表了广泛的同源三聚体蛋白（GlnB-K）家族，它们结合并响应2OG和ATP。在某些细菌门中，GlnB-K蛋白被共价修饰，这取决于将细胞谷氨酰胺感知为氮充足指标的酶。GlnB-K蛋白是氮信息的中心交换所，它们结合并调节各种氮同化调节剂和酶。NifI（1）和NifI（2）包含PII蛋白（NifI）的第二个广泛家族，这些蛋白是异源多聚体，对2OG和ATP有反应，并结合并调节Euryarchaeota和许多细菌中的二氮酶。