A comparative proteomic approach to better define Deinococcus nucleoid specificities

作者：Toueille Magali; Mirabella Boris; Guerin Philippe; de la Tour Claire Bouthier; Boisnard Stephanie; Hong Ha Nguyen; Blanchard Laurence; Servant Pascale; de Groot Arjan; Sommer Suzanne; Armengaud Jean^*

来源：Journal of Proteomics, 2012, 75(9): 2588-2600.

DOI：10.1016/j.jprot.2012.03.002

• Comparative proteomics
• Deinococcus
• DNA compaction
• Nucleoid
• Nucleoid associated proteins

Compared to radiation-sensitive bacteria, the nucleoids of radiation-resistant Deinococcus species show a higher degree of compaction. Such a condensed nucleoid may contribute to the extreme radiation resistance of Deinococcus by limiting dispersion of radiation-induced DNA fragments. Architectural proteins may play a role in this high degree of nucleoid compaction, but comparative genomics revealed only a limited number of Deinococcus homologs of known nucleoid-associated proteins (NAPs) from other species such as Escherichia coli. A comparative proteomic approach was used to identify potentially novel proteins from isolated nucleoids of Deinococcus radiodurans and Deinococcus deserti. Proteins in nucleoid enriched fractions were identified and semi-quantified by shotgun proteomics. Based on normalized spectral counts, the histone-like DNA-binding protein HU appeared to be the most abundant among candidate NAPs from both micro-organisms. By immunofluorescence microscopy, D. radiodurans HU and both DNA gyrase subunits were shown to be distributed throughout the nucleoid structure and absent from the cytoplasm. Taken together, our results suggest that D. radiodurans and D. deserti bacteria contain a very low diversity of NAPs, with HU and DNA gyrase being the main proteins involved in the organization of the Deinococcus nucleoids.

• 出版日期2012-5-17
• 单位中国地震局