A De Cesare1, A Parisi2, F Giacometti3, A Serraino3, S Piva3, M Caruso2, E P L De Santis4, G Manfreda1. 1. Department of Agricultural and Food Sciences, University of Bologna, Ozzano dell'Emilia, Italy. 2. Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Putignano, Italy. 3. Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Italy. 4. Department of Veterinary Medicine, University of Sassari, Sassari, Italy.
Abstract
AIMS: The present study aimed to determine, by multilocus sequence type (MLST), the heterogeneity level of Arcobacter butzleri isolates and to compare MLST and pulsed-field gel electrophoresis (PFGE) in terms of discriminatory power (DI) as well as unidirectional and bi-directional concordance. METHODS AND RESULTS: Arcobacter butzleri isolates (N = 133) from dairy products and environmental samples, collected from dairy plants, were characterized by MLST and PFGE with SacII and classified in 29 sequence types (STs), 47 PFGE and 62 type strains (TS). Among the 119 alleles, 19 were previously unreported and the same for all the STs but two. A significant linkage disequilibrium was detected when the complete ST data set was analysed The DIs of MLST, PFGE and their combination were 0·937, 0·953 and 0·965 respectively. The adjusted Wallace coefficients between MLST and PFGE as well as PFGE and MLST were 0·535 and 0·720 respectively; the adjusted Rand coefficient was 0·612. CONCLUSIONS: The A. butzleri studied population showed recombination to some degree. PFGE showed a DI higher than MLST. Both methods presented good concordance. The TS analysis seems to show persistence of the same strain on time and possible cross-contaminations between food and environmental sites. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights in the A. butzleri population found in raw milk, cheese, and dairy production plants. The data suggest that MLST and PFGE genotypes correlate reasonably well, although their combination results in optimal resolution.
AIMS: The present study aimed to determine, by multilocus sequence type (MLST), the heterogeneity level of Arcobacter butzleri isolates and to compare MLST and pulsed-field gel electrophoresis (PFGE) in terms of discriminatory power (DI) as well as unidirectional and bi-directional concordance. METHODS AND RESULTS:Arcobacter butzleri isolates (N = 133) from dairy products and environmental samples, collected from dairy plants, were characterized by MLST and PFGE with SacII and classified in 29 sequence types (STs), 47 PFGE and 62 type strains (TS). Among the 119 alleles, 19 were previously unreported and the same for all the STs but two. A significant linkage disequilibrium was detected when the complete ST data set was analysed The DIs of MLST, PFGE and their combination were 0·937, 0·953 and 0·965 respectively. The adjusted Wallace coefficients between MLST and PFGE as well as PFGE and MLST were 0·535 and 0·720 respectively; the adjusted Rand coefficient was 0·612. CONCLUSIONS: The A. butzleri studied population showed recombination to some degree. PFGE showed a DI higher than MLST. Both methods presented good concordance. The TS analysis seems to show persistence of the same strain on time and possible cross-contaminations between food and environmental sites. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights in the A. butzleri population found in raw milk, cheese, and dairy production plants. The data suggest that MLST and PFGE genotypes correlate reasonably well, although their combination results in optimal resolution.
Keywords:
Arcobacter butzleri; concordance between genotyping methods; dairy products and dairy plants; multi locus sequence typing; pulsed-field gel electrophoresis
Authors: Marta Caruso; Laura Latorre; Gianfranco Santagada; Rosa Fraccalvieri; Laura Maria Difato; Angela Miccolupo; Loredana Capozzi; Elisabetta Bonerba; Anna Mottola; Antonio Parisi Journal: Ital J Food Saf Date: 2019-02-08
Authors: Paksathorn Kietsiri; Chonchanok Muangnapoh; Woradee Lurchachaiwong; Paphavee Lertsethtakarn; Ladaporn Bodhidatta; Orasa Suthienkul; Norman C Waters; Samandra T Demons; Brian A Vesely Journal: PLoS One Date: 2021-02-05 Impact factor: 3.240