The Clustered Regularly Interspaced Short Palindromic Repeats-Associated System and Its Relationship With Mobile Genetic Elements in Klebsiella

Abstract

Microorganisms have developed many strategies in the process of long-term defense against external attacks, one of which is the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas) bacterial immunological system. In this study, the whole genome of 300 strains of Klebsiella was collected, the CRISPR-Cas system in the strains was statistically analyzed, and the types and structures of CRISPR system in Klebsiella were explored, as well as the correlation between CRISPR and mobile genetic elements (MGEs). Through principal component analysis (PCA), we found that Cas gene, plasmids, integron, IS1, IS609, and enzymes of DNA metabolism were closely related to CRISPR-Cas. Compared the structural characteristics of plasmids, the DinG family helicases, Cas6, Csf2, and IS5 were observed near the CRISPR loci in plasmid, which is also confirmed by the results of PCA that they may be important factors affecting the plasmid with CRISPR.

Inverse Association between the Existence of CRISPR/Cas Systems with Antibiotic Resistance, Extended Spectrum β-Lactamase and Carbapenemase Production in Multidrug, Extensive Drug and Pandrug-Resistant Klebsiella pneumoniae

“…In the work carried out by Wang and colleagues [ 42 ], CRISPR/Cas was detected in 21.32% (29/136) of K. pneumoniae isolates, 14 of which were positive for both CRISPR2 and CRISPR3, whilst other strains were positive for either CRISPR2 ( n = 13) or CRISPR3 ( n = 2). Zhou and colleagues [ 43 ] demonstrated that about one third of all 300 isolates of K. pneumoniae contained this system. By comparison, Lin et al’s [ 44 ] recent study found that only 6 out of 52 isolates of K. pneumoniae had this system and, accordingly, it appears that the CRISPR/Cas system is not widely distributed in K. pneumoniae.…”

Molecular and bacteriological investigations for the co-existence CRISPR/Cas system and β-lactamases of types extended-spectrum and carbapenemases in Multidrug, extensive drug and Pandrug-Resistant Klebsiella pneumoniae

“…Zhou and colleagues ( Zhou et al, 2022 ) focus on the Klebsiella CRISPR-Cas system to investigate the interaction between mobile genetic components and CRISPR as well as the different factors influencing CRISPR. According to the investigation, CRISPR both hinders and defends against foreign mobile devices.…”

“…The remaining isolates tested positive for either CRISPR2 (n = 13) or CRISPR3 (n = 2), with 14 isolates testing positive for both genes. Zhou and colleagues ( Zhou et al, 2022 ) reported that approximately one-third of 300 K. pneumoniae isolates exhibited this mechanism. Comparatively, according to a recent study by Lin et al, only 6 out of 52 K. pneumoniae isolates have this system ( Lin et al, 2016 ).…”