ShmR is essential for utilization of heme as a nutritional iron source in Sinorhizobium meliloti.
نویسندگان
چکیده
The bacterium Sinorhizobium meliloti is able to use heme as a nutritional iron source. Here, we show that the iron-regulated shmR gene encodes an outer membrane protein required for growth on heme. Furthermore, an shmR mutant is resistant to the toxic heme analog gallium protoporphyrin. Thus, the receptor protein of the heme transport system has been identified in S. meliloti.
منابع مشابه
A new small regulatory protein, HmuP, modulates haemin acquisition in Sinorhizobium meliloti
Sinorhizobium meliloti has multiple systems for iron acquisition, including the use of haem as an iron source. Haem internalization involves the ShmR haem outer membrane receptor and the hmuTUV locus, which participates in haem transport across the cytoplasmic membrane. Previous studies have demonstrated that expression of the shmR gene is negatively regulated by iron through RirA. Here, we ide...
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ورودعنوان ژورنال:
- Applied and environmental microbiology
دوره 74 20 شماره
صفحات -
تاریخ انتشار 2008