Identification of Vibrio parahemolyticus Isolated from Seafood via Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry

Vibrio parahaemolyticus is the most common cause of human infections of all members of the Vibrio genus, accounting for between 31 and 50% of the food poisoning cases. Consumption of food contaminated with V. parahaemolyticus can cause severe digestive infection with symptoms of watery or bloody diarrhoea, stomach pain, vomiting, fever, and dehydration. The objective of the study was to establish the reliability of Matrix-Assisted Laser Desorption/Ionization Time оf Flight Mass Spectrometry (MALDI-TOF MS) for identifying V. parahaemolyticus isolated from seafood marketed for human consumption.

A hundred and eighty seafood samples including mussels (Mytilus galloprovincialis), veined rapa whelks (Rapana venosа), bluefish (Pomatomus saltatrix), horse mackerel (Trachurus mediterraneus), gilthead seabream (Sparus aurata), sea bass (Dicentrarchus labrax), Atlantic salmon (Salmo salar), whiteleg shrimp (Litopenaeus vannamei), Argentine shortfin squid (Illex argentinus), and oysters (Ostreidae) were tested by Polymerase Chain Reaction (PCR) and MALDI-TOF MS for the presence of V. parahaemolyticus.

Of the tested 103 isolates, 44 (43%) samples were identified as V. parahaemolyticus by PCR, while 41 (40%) samples were confirmed as V. parahaemolyticus by MALDI-TOF MS. The PCR analysis using non-parametric t-test for comparison of the proportions confirmed 93% of the results obtained by MALDI-TOF MS.

MALDI-TOF MS showed high discriminative capacity and can be used for high reliability fast identification of V. parahaemolyticus in seafood samples.