Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

CRISPR and crRNAs02:53

CRISPR and crRNAs

19.5K
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
19.5K
Mutations in Microorganisms01:18

Mutations in Microorganisms

999
Mutations are heritable changes in an organism’s genome involving alterations in the base sequence of DNA or RNA. These changes can influence cellular processes and phenotypic traits, potentially transforming the unaltered wild type into a mutant form. Such changes, termed forward mutations, are pivotal in shaping the genetic diversity of organisms.RNA viruses exhibit the highest mutation rates due to the absence of robust proofreading mechanisms during genome replication. In contrast,...
999
CRISPR/Cas9 Genome Editing01:28

CRISPR/Cas9 Genome Editing

2.4K
The CRISPR-Cas system serves as a bacterial defense mechanism against invading genetic elements such as viruses and plasmids, forming the foundation for its adaptation as a powerful genome-editing tool. Originally discovered in prokaryotes, this system has been repurposed to revolutionize genetic engineering across a wide range of organisms, including plants, animals, and humans. The core component, Cas9, is an endonuclease derived from Streptococcus pyogenes, capable of introducing...
2.4K
The Antiviral System of Bacteria and Archaea: CRISPR01:23

The Antiviral System of Bacteria and Archaea: CRISPR

899
CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats is a adaptive immune system found in bacteria and archaea that protects against viral infections. This system enables prokaryotic cells to identify, remember, and neutralize foreign genetic elements, primarily bacteriophages, by storing fragments of the invader’s DNA as a genetic memory.The CRISPR immune response begins during an initial infection. Cas (CRISPR-associated) proteins play a central role in this...
899
Homologous Recombination02:31

Homologous Recombination

65.0K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
65.0K
CRISPR01:59

CRISPR

58.7K
Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced...
58.7K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Are We Making Genetically Modified Humans?

The CRISPR journal·2026
Same author

Reply to Z Yu and F Qin.

The American journal of clinical nutrition·2026
Same author

CRISPR-based technologies for large DNA insertions.

Trends in biotechnology·2026
Same author

Pan-Continental Genomic Analysis of Eurasian Perch Uncovers Global Diversity Hotspots and Postglacial Recolonization Patterns.

Ecology and evolution·2026
Same author

Under Pressure: Can CRISPR Deliver Despite Contextual Headwinds?

The CRISPR journal·2026
Same author

<i>Clostridium septicum</i> Alpha Toxin-Based Recombinant Subunit Vaccine Protects Broiler Chickens Against Clostridial Dermatitis.

Avian diseases·2026
Same journal

Genomic evidence for natural selection underlying high-altitude adaptive hemoglobin levels among Peruvian Andeans.

Genome biology and evolution·2026
Same journal

Host Range Breadth Correlates with Genic Diversity in Honeybee Phages.

Genome biology and evolution·2026
Same journal

Genome-wide analysis of an endangered axolotl endemic to Mexico reveals genomic variation associated with body condition, environment and infection by a pathogenic fungus.

Genome biology and evolution·2026
Same journal

Conservation of IAMT preference for indole acetic acid methylation across 250 million years of seed plant divergence, with only one recent evolutionary switch in Ocimum.

Genome biology and evolution·2026
Same journal

Regulatory logic and transposable element dynamics in Caenorhabditis genomes.

Genome biology and evolution·2026
Same journal

Interchromosomal translocations and large deletions drive the evolution of the outlier chromosome in the smallest photosynthetic eukaryote.

Genome biology and evolution·2026
See all related articles

Related Experiment Video

Updated: Mar 15, 2026

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291
06:51

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291

Published on: December 10, 2016

13.4K

CRISPR Diversity and Microevolution in Clostridium difficile.

Joakim M Andersen1, Madelyn Shoup2, Cathy Robinson2

  • 1Department of Food, Processing and Nutritional Sciences, North Carolina State University, NC.

Genome Biology and Evolution
|September 1, 2016
PubMed
Summary
This summary is machine-generated.

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated genes (cas) offer a powerful new method for high-resolution genotyping of Clostridium difficile. This approach enhances our ability to track outbreaks and understand the evolution of this global health threat.

Keywords:
BI/NAP1/RT027/ST1Type-IBCRISPR phylogenyCRISPR typingCRISPR-Cas

More Related Videos

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
09:00

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance

Published on: May 2, 2018

12.5K
CRISPR-mediated Genome Editing of the Human Fungal Pathogen Candida albicans
09:56

CRISPR-mediated Genome Editing of the Human Fungal Pathogen Candida albicans

Published on: November 14, 2018

12.8K

Related Experiment Videos

Last Updated: Mar 15, 2026

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291
06:51

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291

Published on: December 10, 2016

13.4K
Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
09:00

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance

Published on: May 2, 2018

12.5K
CRISPR-mediated Genome Editing of the Human Fungal Pathogen Candida albicans
09:56

CRISPR-mediated Genome Editing of the Human Fungal Pathogen Candida albicans

Published on: November 14, 2018

12.8K

Area of Science:

  • Microbiology
  • Genomics
  • Bacterial Evolution

Background:

  • Virulent Clostridium difficile strains pose a significant global health challenge, causing substantial morbidity and mortality.
  • Traditional typing methods lack the resolution needed for accurate tracking of outbreak strains, genetic diversity assessment, and global phylogenetic monitoring of C. difficile.

Purpose of the Study:

  • To investigate the occurrence and diversity of CRISPR-Cas systems in C. difficile.
  • To evaluate the potential of CRISPR-based phylogeny and high-resolution genotyping for C. difficile isolates.

Main Methods:

  • Analysis of 217 C. difficile genomes to identify and characterize CRISPR-Cas systems.
  • Assessment of CRISPR array occurrence, location, and spacer polymorphism across different strains.
  • Correlation of CRISPR array composition with established typing methods like Sequence Type (ST) analysis.

Main Results:

  • A single Type-IB CRISPR-Cas system was found in all analyzed genomes, with cas gene clusters at conserved locations, indicating vertical evolution.
  • An enrichment of CRISPR arrays (8.5 arrays/genome) was observed in C. difficile compared to other species.
  • CRISPR array composition and spacer polymorphism provided high-resolution genotyping, differentiating closely related strains and correlating with ST analysis.
  • Spacer sequences showed similarity to phage sequences, supporting the role of CRISPR-Cas as a bacterial adaptive immune system.

Conclusions:

  • CRISPR-Cas sequences provide a robust basis for genotyping C. difficile isolates.
  • This method offers insights into micro-evolutionary events and the evolutionary trajectory of C. difficile genomes.
  • CRISPR-based typing significantly enhances the ability to monitor and control C. difficile outbreaks.