Revealing the CRISPR array in bacteria living in our organism

Abstract

CRISPR (clustered regularly interspaced short palindromic repeats) is an immune system used by bacteria to defend themselves from different types of pathogens. It was discovered that this immune system can modify itself in specific regions called spacers due to previous interaction with foreign genetic material from phages and plasmids. Through our research, we have identified in different bacterial isolates CRISPR arrays belonging to the subtypes I-E (present in 42 samples) and I-F (present in 9 samples). The number of spacers in CRISPR arrays was also estimated based on the array length as a possible connection with the systems activity. Our results yielded arrays as small as 200 bp and as large as 1400 bp.