Lactobacillus helveticusis a homofermentative thermophilic lactic acid bacteriathat is mainly used in the manufacture of Swiss type and long-ripened Italianhard cheeses. In this study, the presence of Clustered Regularly InterspacedShort Palindromic Repeats (CRISPR) were analysed in 25L. helveticusgenomesand identified in 23 of these genomes. A total of 40 CRISPR loci wereidentified and classified into five main families based on CRISPR repeats:Ldbu1, Lsal1, Lhel1, Lhel2 and a new repeat family named Lhel3. Spacers hada size between 30 and 40 bp whereas repeats have an average size of 30 bp,with three longer repeats. The analysis displayed the presence of conservedspacers in 23 of the 40 CRISPR loci. A geographical distribution ofL.helveticusisolates with similar CRISPR spacer array profiles were not observed.Based on the presence of the signature protein Cas3, all CRISPR loci belongedto Type I. This analysis demonstrated a great CRISPR array variability withinL. helveticus, which could be a useful tool for genotypic strain differentiation.A next step will be to understand the possible role of CRISPR/Cas system forthe resistance ofL. helveticusto phage infection.
Survey on the CRISPR Arrays in Lactobacillus Helveticus Genomes / Scaltriti, E.; Carminati, D.; Cortimiglia, C.; Ramoni, R.; Sørensen, K. I.; Giraffa, G.; Zago, M.. - In: LETTERS IN APPLIED MICROBIOLOGY. - ISSN 0266-8254. - 68:(2019), pp. 394-402. [10.1111/lam.13128]
Survey on the CRISPR Arrays in Lactobacillus Helveticus Genomes
R. Ramoni;
2019-01-01
Abstract
Lactobacillus helveticusis a homofermentative thermophilic lactic acid bacteriathat is mainly used in the manufacture of Swiss type and long-ripened Italianhard cheeses. In this study, the presence of Clustered Regularly InterspacedShort Palindromic Repeats (CRISPR) were analysed in 25L. helveticusgenomesand identified in 23 of these genomes. A total of 40 CRISPR loci wereidentified and classified into five main families based on CRISPR repeats:Ldbu1, Lsal1, Lhel1, Lhel2 and a new repeat family named Lhel3. Spacers hada size between 30 and 40 bp whereas repeats have an average size of 30 bp,with three longer repeats. The analysis displayed the presence of conservedspacers in 23 of the 40 CRISPR loci. A geographical distribution ofL.helveticusisolates with similar CRISPR spacer array profiles were not observed.Based on the presence of the signature protein Cas3, all CRISPR loci belongedto Type I. This analysis demonstrated a great CRISPR array variability withinL. helveticus, which could be a useful tool for genotypic strain differentiation.A next step will be to understand the possible role of CRISPR/Cas system forthe resistance ofL. helveticusto phage infection.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
