Subtyping of Campylobacter jejuni by Using Capillary Electrophoresis

24 Campylobacter jejuni is a common cause of the frequently reported foodborne diseases in 25 the developed and developing nations. This manuscript describes the development of multiple26 locus variable number tandem repeat analysis (MLVA) using capillary electrophoresis as a novel 27 typing method for microbial source tracking and epidemiological investigation of C. jejuni. 28 Among 36 tandem repeat loci detected by Tandem Repeat Finder program, 7 variable number 29 tandem repeat (VNTR) loci were selected and used for characterizing 60 isolates recovered from 30 chicken meat samples from retail shops, samples from chicken meat processing factory, and 31 stool samples. The discrimination ability of MLVA was compared with that of multilocus 32 sequence typing (MLST). MLVA (diversity index of 0.97 with 31 MLVA types) provided 33 slightly higher discrimination than MLST (diversity index of 0.95 with 25 MLST types). The 34 overall concordance between MLVA and MLST was estimated at 63% by adjusted Rand 35 coefficient. MLVA predicted MLST type better than MLST predicted MLVA type, as reflected 36 by Wallace coefficient (Wallace coefficient for MLVA→MLST vs MLST→MLVA, 86% vs. 37 51%). MLVA is a useful tool and can be used for effective monitoring of C. jejuni and 38 investigation of epidemics caused by C. jejuni. 39