
A new mechanism of CRISPR-Cas-targeted plasmid persistence in subpopulations of bacterial cells
CRISPR-Cas systems are widely recognized as a genome editing tool. In nature, these systems play the role of bacterial adaptive immunity against bacteriophages and other mobile genetic elements. It is generally believed that mutations are responsible for overcoming such defenses. In a study led by Konstantin Severinov involving several groups from Russia, the United States and Chile, it was found that even with a fully functional CRISPR-Cas and an unmutated target sequence, the plasmid can persist for many generations in a small subpopulation of E. coli cells. A model system using fluorescent proteins made it possible to trace the activity of the CRISPR-Cas system at the level of single living bacterial cells. The work was published in the Proceedings of the National Academy of Sciences of USA.
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- Vadim Tikhonovich Ivanov has passed away
administration
IV.8 An outstanding scientist, director of the IBCh RAS, winner of many awards, professor, academician Vadim Tikhonovich Ivanov has passed away on Friday, 8 April 2022.
- IBCH RAS mourns passing of Sidney Altman
administration
IV.6 An outstanding scientist, a laureate of Rosenstiel Award (1988) and Nobel prize in chemistry (1989), Sterling Professor of Molecular, Cellular, and Developmental Biology at Yale University and a member of the International Advisory Board of the IBCh RAS, Sidney Altman passed away on April 5, 2022 at the age of 82. He made a fundamental contribution to the biological and medical sciences. The staff and administration of the IBCh RAS express their sincere condolences to the family, friends and colleagues of Sidney Altman.
- Genetically-encoded BRET-activated photodynamic therapy for the treatment of deep-seated tumors
science news
III.16 Being targeted to tumor cells, genetically-encoded NanoLuc-miniSOG construct generates internal light source and sensitizer pair, which makes possible PDT effect under BRET activation to treat tumors at virtually unlimited depth.