Effect of a bacteriophage T5virus on growth of Shiga toxigenic Escherichia coli and Salmonella strains in individual and mixed cultures

Table 1 Effect of phage AKFV33 treated individual and mixture of STEC and Salmonella at different MOIs

Species/Serotypes	Bacterial	Source	Susceptibility¹	Bacterial individual or mixed culture	Mean OD_600nm at each MOI²
Species/Serotypes	strains #		(MOI value)		Phage-free Control	0.01	0.1	1	10	100	1000	Across MOIs
STEC O157:H7	R508N	Bovine	9 × 10⁻⁶	Individual	0.261	0.006a	0.004a	0.001a	0.001a	0.001a	0a	0.002
STEC O26:H11	EC19960464	Bovine	6 × 10⁻⁵	Individual	0.310	0.05a	0.011b	0.004b	0.002b	0b	0b	0.011
STEC O145:NM	EC19970355	Human	4 × 10⁻³	Individual	0.224	0.156a	0.067b	0.067b	0.02c	0.015c	0.003c	0.055
S. I 4, [5],12:i	20,104,603	Porcine	4	Individual	0.162	0.165	0.094a	0.097a	0.063a	0.063a	0.048b	0.088
S. Typhimurium	ATCC14028	Porcine	3	Individual	0.262	0.227	0.207	0.220	0.174	0.221	0.038a	0.181
				O26:H11 + O157:H7	0.315	0.013a^*	0.005a	0.006a	0a	0.001a	0a	0.004
				O145:NM + O157:H7	0.268	0.009a^(***)	0.005a^(**)	0.004a^(**)	0.003a	0.005a	0.003a	0.005
				O26:H11 + O145:NM + O157:H7	0.316	0.014a^(**)	0.004b^(**)	0.005b^(**)	0.001b	0.002b	0.002b	0.005
				S. I 4, [5],12:i + O157:H7	0.230	0.099a^**	0.002c^***	0.064b^**	0.004c^**	0.012c^**	0.003c^*	0.031
				S. Typhimurium + O157:H7	0.262	0.037a^(***)	0.015a^(***)	0.014a^(***)	0.008a^(***)	0.009a^(***)	0.007a	0.015
				S. I 4, [5],12:I + S. Typhimurium + O157:H7	0.228	0.004a^*(*)	0.004a^*(*)	0.011a^*(*)	0.008a^(*)	0.008a^(*)	0.008a^*	0.007

¹Susceptibility of strains to phages were determined by microplate phage virulence assay for each MOI (Multiplicity of infection) value
²The blank values were subtracted from absorbance measures at 600 nm, to give a final corrected optical density. Mean OD_600nm at each MOI were calculated by averaging OD_600nm from 2 h, 4 h, 6 h, 8 h and 10 h
Letters which differ after the mean values indicate differences (P < 0.05) among MOIs within each bacterial culture
Asterisks^*, ^** and ^*** indicate a statistical difference between phage-treated individual and mixed culture within same MOI at P < 0.05, P < 0.01 and P < 0.001, respectively

ISSN: 1743-422X