018 (0.042) pyrC 489 bp 163 aa 55; 14.8% (219; 15.4%) 14; 35.9% (41; 28.9%) 20; 38.2% 3; 21.4% 48; 9.8% (107; 21.8%) 11; 6.8% (31; 19.0%) 0.986 (0.981) 0.791 BB-94 supplier (0.753) 0.045 (0.049) tnaA 423 bp 141 aa 44; 11.8% (152; 10.7%) 8; 20.5% (25; 17.6%) 15; 34.1% 4; 50.0% 41; 9.7% (89; 21.0%)

6; 4.3% (22; 15.6%) 0.974 (0.97) 0.355 (0.440) 0.019 (0.023) total 3669 bp 1223 aa 372; 100% (1424; 100%) 39; 100% (142; 100%) 125; 33.6% 15; 29.9% 348; 9.5% (812; 22.1%) 28; 2.3% (131; 10.7%)       Ain-frame fragment size. BValues in parentheses are computed based on the data of the entire pubMLST dataset. C d N /d S ratio, ratio of non-synonymous to synonymous mutations, value <1 indicates purifying selection of loci. *For the one occurring allele no variable sites could be determined. Diversity of sequence types By applying MLST analysis, the 130 strains analyzed in JQEZ5 molecular weight our study resulted in 82 unique STs of which 68 (82.9%) were new in comparison to pubMLST database entries. Even after dividing the total collection into geographical subsets, the number of different and new STs remained high (Table 2). Individual STs were mostly recovered once, but (especially for the Sri Lankan strains) specific STs (e.g. STs 394, 395, 397) were more frequently isolated, thereby the most frequently identified ST was ST394 (7.7%) and the 64 least frequent STs occurred only once (each 0.8%) (Additional file

1: Table S1). Table 2 Properties of the analyzed V . parahaemolyticus populations   Number of isolates Number of STs (new STs) Number of pSTs (new pSTs) Sri Lanka 43 16 (15) 9 (4)  -Chillaw 11 6 (6) 6 (1)  -Puttalam 21 12 (11) 7 (3)

 -Madurankuliya 11 6 (5) 4 (1) Ecuador 27 21 (19) 13 (8)  -market 9 8 (8) 6 (4)  -Machala 10 8 (6) 6 (2)  -Balao 2 2 (2) 2 (1)  -Guayaquil 6 5 (5) 3 (1) NB-Seas 26 19 (16) 13 (6)  -North Sea 8 4 (4) 4 (2)  -Baltic Sea 14 11 (8) 8 (2)  -Kattegat and Skagerrak 4 4 (4) 4 (2) German retail 34 29 (21) 10 (3) All isolates 130 82 (68) 31 (19) The individual loci possessed 41 (pntA) to 65 (gyrB) unique alleles of which 23.6% (dnaE) to 43.1% (gyrB) were new, leading to a total of 125 (33.6%) alleles new to the database. Up to 40.9% of the individual alleles at a single locus were present in more than one distinct ST. The distinct alleles were characterized by different numbers of variable sites with gyrB as the most diverse locus possessing only 47 Thiamet G (8%) variable sites. The higher number of combinations of different SNPs led to the high number of distinct alleles. The d N /d S value indicates the kind of selection in a chosen gene and population: a d N /d S  < 1 is indicative of purifying selection, d N /d S  = 1 of neutral selection and d N /d S  > 1 of positive selection. The Simpsons Index of diversity (D) measures the Bucladesine chemical structure ability of a typing scheme to distinguish between unrelated strains [38].