Project description:To examine Alr3614 influence on the expression of Anabaena sp. PCC 7120, we have used customized microarrays to identify genes potentially regulated by this short DNA-binding protein. We compared the expression of an Alr3614-deletion strain with an Alr3614-complementation strain.
Project description:Here, we report the comparison of transcriptomes of Anabaena sp. PCC7120 and the FurB(Zur) deletion derivative strain (MN38). Anabaena sp PCC7120 is a cyanobacterium that differentiates specialized nitrogen-fixing cells called heterocysts and that is capable of forming biofilms. Our data showed that the deletion of FurB negativily affected the heterocyst development and the biofilm formation. In addition, the RNA-seq data together with gel retardation assays unveiled that FurB is directly involved in the regulation of several genes related to heterocyst development and biofilm formation and other novel functions different from the ones related to the canonical Zur regulon.
Project description:In order to examine the response of Anabaena sp. PCC 7120 to an infection of the Cyanophage A1, we have used customized microarrays to identify genes potentially up- or downregulated by the infection. For this we compared cell culture before and after infection.
Project description:Here, we report the comparison of transcriptomes of Anabaena sp. PCC7120 and a FurC-overexpressing derivative strain grown under standard conditions (BG11) and after 48 hours of nitrogen step-down (BG110). Anabaena sp PCC7120 is a cyanobacterium that differentiates specialized nitrogen-fixing cells called heterocysts. Our data suggests that FurC directly controls the regulation of heterocyst differentiation and nitrogen fixation in this cyanobacterium. In addition, we found that FurC is also clearly involved in the regulation of several genes belonging to different functional categories, such as iron metabolism, photosynthesis and regulatory functions.
Project description:Deletion of the global transcription factor PacR in Anabaena triggers heterocyst formation even in NO3- containing medium, likely due to impaired NO3- uptake and disrupted NH4+ assimilation in the GOGAT cycle. This phenotype may be exacerbated by reduced PSI-yield and reduced expression of ferredoxin, which may lead to less reducing equivalents for nitrogen uptake and fixation. These results highlight PacR’s role as a global regulator of carbon metabolism and photosynthesis while also establishing its involvement in regulating nitrogen metabolism.
Project description:Advances in biotechnology generated wide range of microbial genome and their related protein database. Freshwater cyanobacterium Anabaena PCC7120 sensory rhodopsin, ASR in contrast to classical haloarchaeal sensory rhodopsins interacts with putative soluble transducer, ASRT. The 125 amino acid transducer exists as a soluble protein and is involved in photoreceptor binding. Recombinant DNA tools in biotechnology conventionally support the use of affinity tags for ease of protein purification and subsequent studies. The ASRT exists as a stable tetramer. Both X-ray crystal structure and solution NMR results with ASRT utilizing hexa-histidine affinity tag reveal it as a primarily β-stranded protein We have observed that the affinity tagged ASRT exhibits altered oligomeric stability. In this communication we outlined the effect of commonly used denaturant, Sodium Dodecyl Sulfate (SDS) on the tetrameric packing of ASRT. Our results support that N-terminus hexa-histidine tagged ASRT displayed unusual SDS-resistant structure. The unusual stability of ASRT and its homologues present in other microbial population could provide further insight towards their role in receptor, other ligand binding and signaling.
Project description:A comparative proteomics study to investigate a saxitoxin producing and non-toxic strains of Anabaena circinalis. Anabaena circinalis is a freshwater and bloom-forming cyanbacterium