Microbial CRISPR–Cas System: From Bacterial Immunity to Next-Generation Antimicrobials

  • Alka Mehra


Microbes live in multi-microbial communities called microbiome. Discoveries that can help in the regulation of the composition of the microbiome are likely to impact diverse functions of microbes from health, environment, to biotechnology. Antimicrobials offer such regulatory potential and are slowly but surely evolving for the benefit of human health and biotechnology. Antibiotics are the first discovered antimicrobials which are low molecular weight natural microbial products that inhibit the growth of other microbes. However, emergence of microbial resistance to conventional antibiotics has presented an urgent need for novel antimicrobials. Here, we describe another native microbial machinery, CRISPR (“clustered regularly interspaced short palindromic repeats”)–Cas (“CRISPR associated”) system, that confers adaptive immunity to microbes by employing CRISPR RNAs to recognize and destroy complementary nucleic acids of invasive foreign genetic elements. Further, sequence-based targeting by CRISPR–Cas system has been leveraged for the development of sequence-specific novel antimicrobials, genome editing, and genome regulation tools.


Horizontal Gene Transfer Genome Editing CRISPR Locus CRISPR System Protospacer Adjacent Motif 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Alka Mehra thanks Dr. V. C. Kalia and Dr. Yogendra Singh of CSIR-Institute of Genomics and Integrative Biology (IGIB) for providing this opportunity.


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© Springer India 2015

Authors and Affiliations

  1. 1.Allergy and Infectious DiseasesCSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB)DelhiIndia

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