2023年7月23日 · The Gabija complex is a prokaryotic antiviral system consisting of the GajA and GajB proteins. GajA was identified as a DNA nicking endonuclease but the functions of GajB and the complex remain unknown. Here, we show that synergy between GajA-mediated DNA cleavage and nucleotide hydrolysis by GajB i …

2023年11月22日 · Gabija protein A (GajA) is a DNA endonuclease that tetramerizes to form the core of the anti-phage defence complex. Two sets of Gabija protein B (GajB) dimers dock at opposite...

2024年3月12日 · Here, to explore how the Gabija system is activated for anti-phage defence, we report its cryo-electron microscopy structures in five states, including apo GajA, GajA in complex with DNA,...

2024年1月29日 · GajA is a sequence-specific DNA-cleaving enzyme in the presence of Mg 2+, its activity is completely inhibited by the high concentration of NTP and dNTP 9. Prior research indicates that GajA...

2021年5月21日 · The GajA protein is revealed as a sequence-specific DNA nicking endonuclease unique in that its activity is strictly regulated by nucleotide concentration. NTP and dNTP at physiological concentrations can fully inhibit the robust DNA cleavage activity of GajA.

研究发现Gabija系统通过流产感染方式表现出广泛而有效的噬菌体抗性，并且GajA和GajB对其功能至关重要。GajA表现出特异性的寡聚化和DNA结合特性，后者被NTP强烈抑制。出乎意料的是，GajB表现出很强的(d)A/(d)GTP水解活性，但没有解旋酶活性。

Cheng et al. reveal the molecular mechanism of the widespread Gabija prokaryotic immune system, in which the synergy between GajA, an NTP-sensing DNA nickase, and GajB, a DNA-terminus-dependent (d)A/(d)GTPase, causes a cascade suicide effect to …

2023年8月7日 · Here, we present the cryo-EM structures of GajA alone and the GajAB complex. GajA assembles into a tetramer via interactions mediated by both the ATPase domain and the nuclease domain. We also revealed that the GajA and GajB assemble into a heteromeric octamer with four molecules of GajA and four molecules of GajB, which is

2024年4月16日 · As one of the most prevalent anti-phage defense systems in prokaryotes, Gabija consists of a Gabija protein A (GajA) and a Gabija protein B (GajB). The assembly and function of the Gabija system...

Here, to explore how the Gabija system is activated for anti-phage defence, we report its cryo-electron microscopy structures in five states, including apo GajA, GajA in complex with DNA, GajA bound by ATP, apo GajA-GajB, and GajA-GajB in complex with ATP and Mg 2+. GajA is a rhombus-shaped tetramer with its ATPase domain clustered at the ...