CRISPR–Cas systems exploit viral DNA injection to establish and maintain adaptive immunity

Joshua W. Modell; Wenyan Jiang; Luciano A. Marraffini

doi:10.1038/nature21719

CRISPR–Cas systems exploit viral DNA injection to establish and maintain adaptive immunity

Nature ◽

10.1038/nature21719 ◽

2017 ◽

Vol 544 (7648) ◽

pp. 101-104 ◽

Cited By ~ 67

Author(s):

Joshua W. Modell ◽

Wenyan Jiang ◽

Luciano A. Marraffini

Keyword(s):

Adaptive Immunity ◽

Viral Dna ◽

Dna Injection

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2P063 Expression and purification of bacteriophage T5 A1 and A2 proteins are related with viral DNA injection(30. Protein function (II),Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)

Seibutsu Butsuri ◽

10.2142/biophys.46.s311_3 ◽

2006 ◽

Vol 46 (supplement2) ◽

pp. S311

Author(s):

Tomoko Nakao ◽

Laure Plancon ◽

Lucienne Letellier

Keyword(s):

Protein Function ◽

Poster Session ◽

Expression And Purification ◽

Viral Dna ◽

Meeting Program ◽

Dna Injection ◽

Bacteriophage T5

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The size of the immune repertoire of bacteria

10.1101/565366 ◽

2019 ◽

Author(s):

Serena Bradde ◽

Armita Nourmohammad ◽

Sidhartha Goyal ◽

Vijay Balasubramanian

Keyword(s):

Immune System ◽

Adaptive Immunity ◽

Adaptive Immune System ◽

Optimal Size ◽

Immune Repertoire ◽

Viral Dna ◽

Trade Off ◽

Adaptive Immune ◽

Dna Elements ◽

Large Genomes

Some bacteria and archaea possess an immune system, based on the CRISPR-Cas mechanism, that confers adaptive immunity against phage. In such species, individual bacteria maintain a “cassette” of viral DNA elements called spacers as a memory of past infections. The typical cassette contains a few dozen spacers. Given that bacteria can have very large genomes, and since having more spacers should confer a better memory, it is puzzling that so little genetic space would be devoted by bacteria to their adaptive immune system. Here, we identify a fundamental trade-off between the size of the bacterial immune repertoire and effectiveness of response to a given threat, and show how this tradeoff imposes a limit on the optimal size of the CRISPR cassette.

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Use of Antibody to aid Visualization of Protein at the Termini of Bacteriophage Ø29 DNA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002385 ◽

1980 ◽

Vol 38 ◽

pp. 540-541

Author(s):

Dwight Anderson ◽

Charlene Peterson ◽

Gursaran Notani ◽

Bernard Reilly

Keyword(s):

Electron Microscopy ◽

Bacillus Subtilis ◽

Dna Synthesis ◽

Restriction Endonuclease ◽

Protein Complex ◽

Protein Product ◽

Viral Dna ◽

Small Proteins ◽

Antibody Labeling ◽

Subtilis Bacteriophage

The protein product of cistron 3 of Bacillus subtilis bacteriophage Ø29 is essential for viral DNA synthesis and is covalently bound to the 5’-termini of the Ø29 DNA. When the DNA-protein complex is cleaved with a restriction endonuclease, the protein is bound to the two terminal fragments. The 28,000 dalton protein can be visualized by electron microscopy as a small dot and often is seen only when two ends are in apposition as in multimers or in glutaraldehyde-fixed aggregates. We sought to improve the visibility of these small proteins by use of antibody labeling.

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