The CRISPR–Cas system evolved to provide adaptive immunity in bacteria and archaea against invading genetic elements, such as viruses and plasmids. The mechanism of interference is based on CRISPR RNAs, which are derived from foreign DNA and mediate the detection of invading nucleic acids, followed by degradation by the Cas proteins.
Pseudomonas aeruginosa is an opportunistic pathogen that infects humans with compromised natural defences.
It is estimated that 170 million people globally are infected with the hepatitis C virus (HCV).
Metagenomics is a powerful tool that can be used to analyse microbial communities regardless of the ability of member organisms to be cultured in the laboratory. Metagenomics is based on the genomic analysis of microbial DNA that is extracted directly from communities present in samples such as soil, water or faeces.
The type IV secretion systems of Gram-negative bacteria are evolutionarily related to bacterial conjugation systems. Gram-negatives use type IV secretion systems for a variety of biological functions including the exchange of genetic material with other bacteria and the translocation of oncogenic DNA and effector proteins into eukaryotic host cells.