NtcA-dependent expression of the devBCA operon, encoding a heterocyst-specific ATP-binding cassette transporter in Anabaena spp.
نویسندگان
چکیده
The devBCA operon, encoding subunits of an ATP-binding cassette exporter, is essential for differentiation of N(2)-fixing heterocysts in Anabaena spp. Nitrogen deficiency-dependent transcription of the operon and the use of its transcriptional start point, located 762 (Anabaena variabilis strain ATCC 29413-FD) or 704 (Anabaena sp. strain PCC 7120) bp upstream of the translation start site, were found to require the global nitrogen transcriptional regulator NtcA. Furthermore, NtcA was shown to bind in vitro to the promoter of devBCA.
منابع مشابه
HetR-dependent and -independent expression of heterocyst-related genes in an Anabaena strain overproducing the NtcA transcription factor.
Heterocyst development in the cyanobacterium Anabaena sp. strain PCC 7120 depends on both the global nitrogen control transcription factor NtcA and the cell differentiation regulatory protein HetR, with expression of ntcA and hetR being dependent on each other. In this study we constructed strains that constitutively express the ntcA gene leading to high levels of NtcA protein irrespective of t...
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Anabaena sp. strain PCC 7120 is a filamentous cyanobacterium that fixes N(2) in specialized cells called heterocysts, which differentiate from vegetative cells in a process that requires the nitrogen control transcription factor NtcA. 2-Oxoglutarate-stimulated binding of purified NtcA to wild-type and modified versions of the ntcA gene promoter from Anabaena sp. was analyzed by mobility shift a...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 183 12 شماره
صفحات -
تاریخ انتشار 2001