ANTIMICROBIAL ACTIVITY OF Yersinia spp. BACTERIOCINS PRODUCING STRAINS ON DIFFERENT BIOTYPES OF Y. enterocolitica

BRARDA, BRENDA S.; IRIARTE, HEBE J.; LUCERO ESTRADA, CECILIA; ESCUDERO, MARÍA ESTHER; FAVIER, GABRIELA

Mendoza

Congreso; XL REUNIÓN ANUAL DE LA SOCIEDAD DE BIOLOGÍA DE CUYO; 2022

Sociedad de Biología de Cuyo

ANTIMICROBIAL ACTIVITY OF Yersinia spp. BACTERIOCINS PRODUCING STRAINS ONDIFFERENT BIOTYPES OF Y. enterocoliticaBrarda BS1, Iriarte HJ1,2, Lucero Estrada CSM1,2, Escudero ME1, Favier GI11Área de Microbiología e Inmunología, FQBF, Universidad Nacional de San Luis, San Luis, Argentina. 2Instituto Multidisciplinario deInvestigaciones Biológicas del Consejo Nacional de Investigaciones Científicas y Técnicas (IMIBIO - CONICET), San Luis, Argentina.E-mail: brendabrarda@gmail.comBacteriocins are polypeptides that have the ability to be bactericidal or bacteriostatic against sensitive bacteria of the same or closely relatedspecies. The producing cells are immune to their bacteriocins. Non-pathogenic Yersinia species studied in our laboratories, such as Y.intermedia and Y. enterocolitica biotype (B) 1A, are bacteriocin producers and exhibited an inhibitory effect on pathogenic Y. enterocoliticastrains associated with gastrointestinal pathologies and immunological sequelae in humans. The aim of this work was to evaluate theantimicrobial activity of non-pathogenic Yersinia spp. bacteriocins producing strains (BPS) on pathogenic Y. enterocolitica biotypes. Forthis purpose, Y. intermedia B1 O:35-37-40 (MEE 019) and Y. enterocolitica B1A O:5 (LVF 010) were used as BPS. Y. enterocolitica B1B(WAP+), Y. enterocolitica B2 (W1024, GFB002, and GFO041), Y. enterocolitica B3 (GFO045), and Y. enterocolitica B4 (MHC700,29C/43, GFO64CH and GFO68CH), were used as indicator strains (IS). The “spot technique” was performed. Briefly, BPS and IS werecultured in trypticase soy broth at 25°C for 18 h and adjusted to a concentration corresponding to a DOʎ610 0.2. Aliquots of each BPS wereplaced in wells of culture media previously inoculated with IS and incubated at 20°C for 48 h, in duplicate. Halo diameters were measuredin millimeters with a digital caliper and the sensible or resistance ISs were determined by the presence or absence of this halos around theBPS. WAP+, GFO041, GFB002, MHC700, 29C/43, GFO64CH, and GFO68CH were sensitive to both BPS tested. Y. enterocolitica W1024was resistant to both BPS, and Y. enterocolitica GFO045 was sensitive to Y. enterocolitica LVFO10 but resistant to Y. intermedia MEE019.These results encourage the hypothesis that bacteriocins produced by Yersinia strains considered non-pathogenic have antagonistic capacityagainst pathogenic Y. enterocolitica strains and would suggest that antimicrobial effect of these bacteriocins is specific of the strain but ithas no relationship with the Y. enterocolitica biotype.