Corrigendum to “Inhibition of in vitro growth of Shiga toxin-producing Escherichia coli O157:H7 by probiotic Lactobacillus strains due to production of lactic acid”[Int. J. Food Microbiol. 68 (2001) 135–140]

Escherichia coli O157:H7 is the predominant cause of diarrhea-associated hemolytic uremic syndrome (HUS) worldwide. Its cardinal virulence traits are Shiga toxins, which are encoded by stx genes, the most common of which are stx1a, stx2a, and stx2c. The toxins these genes encode differ in their in vitro and experimental phenotypes, but the human population-level impact of these differences is poorly understood. Using Shiga toxin-encoding bacteriophage insertion typing and real-time polymerase chain reaction, we genotyped isolates from 936 E. coli O157:H7 cases and verified HUS status via chart review. We compared the HUS risk between isolates with stx2a and those with stx2a and another gene and estimated additive interaction of the stx genes. Adjusted for age and symptoms, the HUS incidence of E. coli O157:H7 containing stx2a alone was 4.4% greater (95% confidence interval (CI) −0.3%, 9.1%) than when it occurred with stx1a. When stx1a and stx2a occur together, the risk of HUS was 27.1% lower (95% CI −87.8%, −2.3%) than would be expected if interaction were not present. At the population level, temporal or geographic shifts toward these genotypes should be monitored, and stx genotype may be an important consideration in clinically predicting HUS among E. coli O157:H7 cases.

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Comparison of effects of mild heat combined with lactic acid on Shiga toxin producing Escherichia coli O157:H7, O103, O111, O145 and O26 inoculated to spinach and soybean sprout

Food Control ◽

10.1016/j.foodcont.2014.08.038 ◽

2015 ◽

Vol 50 ◽

pp. 184-189 ◽

Cited By ~ 13

Author(s):

Abdullah Dikici ◽

Ahmet Koluman ◽

Mehmet Calicioglu

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Shiga Toxin ◽

Escherichia Coli O157 ◽

Mild Heat

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Control of Escherichia coli O157:H7 with Sodium Metasilicate

Journal of Food Protection ◽

10.4315/0362-028x-67.7.1501 ◽

2004 ◽

Vol 67 (7) ◽

pp. 1501-1506 ◽

Cited By ~ 20

Author(s):

GEORGE H. WEBER ◽

JUDY K. O'BRIEN ◽

FREDRIC G. BENDER

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Room Temperature ◽

Sodium Metasilicate ◽

Antimicrobial Activities ◽

Intervention Strategies ◽

Trisodium Phosphate ◽

Escherichia Coli O157 ◽

E Coli

Three intervention strategies—trisodium phosphate, lactic acid, and sodium metasilicate—were examined for their in vitro antimicrobial activities in water at room temperature against a three-strain cocktail of Escherichia coli O157:H7 and a three-strain cocktail of “generic” E. coli. Both initial inhibition and recovery of injured cells were monitored. When 3.0% (wt/wt) lactic acid, pH 2.4, was inoculated with E. coli O157:H7 (approximately 6 log CFU/ml), viable microorganisms were recovered after a 20-min exposure to the acid. After 20 min in 1.0% (wt/wt) trisodium phosphate, pH 12.0, no viable E. coli O157:H7 microorganisms were detected. Exposure of E. coli O157:H7 to sodium metasilicate (5 to 10 s) at concentrations as low as 0.6%, pH 12.1, resulted in 100% inhibition with no recoverable E. coli O157:H7. No difference in inhibition profiles was detected between the E. coli O157:H7 and generic strains, suggesting that nonpathogenic strains may be used for in-plant sodium metasilicate studies.

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A comparison of Shiga-toxin negative Escherichia coli O157 aflagellate and intimin deficient mutants in porcine in vitro and in vivo models of infection

Veterinary Microbiology ◽

10.1016/j.vetmic.2005.10.033 ◽

2006 ◽

Vol 113 (1-2) ◽

pp. 63-72 ◽

Cited By ~ 13

Author(s):

Angus Best ◽

Roberto M. La Ragione ◽

Derek Clifford ◽

William A. Cooley ◽

A. Robin Sayers ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Escherichia Coli O157 ◽

In Vivo Models

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Evaluation of Lactic Acid as an Initial and Secondary Subprimal Intervention for Escherichia coli O157:H7, Non-O157 Shiga Toxin–Producing E. coli, and a Nonpathogenic E. coli Surrogate for E. coli O157:H7

Journal of Food Protection ◽

10.4315/0362-028x.jfp-11-520 ◽

2012 ◽

Vol 75 (9) ◽

pp. 1701-1708 ◽

Cited By ~ 15

Author(s):

C. I. PITTMAN ◽

I. GEORNARAS ◽

D. R. WOERNER ◽

K. K. NIGHTINGALE ◽

J. N. SOFOS ◽

...

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Shiga Toxin ◽

Hazard Analysis ◽

Control Point ◽

Escherichia Coli O157 ◽

Meat Industry ◽

Bacterial Reduction ◽

E Coli ◽

Critical Control Point

Lactic acid can reduce microbial contamination on beef carcass surfaces when used as a food safety intervention, but effectiveness when applied to the surface of chilled beef subprimal sections is not well documented. Studies characterizing bacterial reduction on subprimals after lactic acid treatment would be useful for validations of hazard analysis critical control point (HACCP) systems. The objective of this study was to validate initial use of lactic acid as a subprimal intervention during beef fabrication followed by a secondary application to vacuum-packaged product that was applied at industry operating parameters. Chilled beef subprimal sections (100 cm2) were either left uninoculated or were inoculated with 6 log CFU/cm2 of a 5-strain mixture of Escherichia coli O157:H7, a 12-strain mixture of non-O157 Shiga toxin–producing E. coli (STEC), or a 5-strain mixture of nonpathogenic (biotype I) E. coli that are considered surrogates for E. coli O157:H7. Uninoculated and inoculated subprimal sections received only an initial or an initial and a second “rework” application of lactic acid in a custom-built spray cabinet at 1 of 16 application parameters. After the initial spray, total inoculum counts were reduced from 6.0 log CFU/cm2 to 3.6, 4.4, and 4.4 log CFU/cm2 for the E. coli surrogates, E. coli O157:H7, and non-O157 STEC inoculation groups, respectively. After the second (rework) application, total inoculum counts were 2.6, 3.2, and 3.6 log CFU/cm2 for the E. coli surrogates, E. coli O157:H7, and non-O157 STEC inoculation groups, respectively. Both the initial and secondary lactic acid treatments effectively reduced counts of pathogenic and nonpathogenic strains of E. coli and natural microflora on beef subprimals. These data will be useful to the meat industry as part of the HACCP validation process.

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Shiga Toxin Stx2 Production Is Promoted by Enrofloxacin in Experimental In Vitro–Selected Mutants of Escherichia coli O157:H7 Resistant to Fluoroquinolones

Foodborne Pathogens and Disease ◽

10.1089/fpd.2008.0165 ◽

2009 ◽

Vol 6 (2) ◽

pp. 257-259 ◽

Cited By ~ 1

Author(s):

Claire Maurer ◽

Daniele Meunier ◽

Jean-Yves Madec

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Escherichia Coli O157

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Escherichia coli O157:H7 Strain Origin, Lineage, and Shiga Toxin 2 Expression Affect Colonization of Cattle

Applied and Environmental Microbiology ◽

10.1128/aem.00391-09 ◽

2009 ◽

Vol 75 (15) ◽

pp. 5074-5081 ◽

Cited By ~ 30

Author(s):

Ross M. S. Lowe ◽

Danica Baines ◽

L. Brent Selinger ◽

James E. Thomas ◽

Tim A. McAllister ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Escherichia Coli O157 ◽

Human Origin ◽

E Coli ◽

Unknown Factor ◽

Shiga Toxin 2 ◽

The Impact ◽

Dose Dependent

ABSTRACT Enterohemorrhagic Escherichia coli O157:H7 has evolved into an important human pathogen with cattle as the main reservoir. The recent discovery of E. coli O157:H7-induced pathologies in challenged cattle has suggested that previously discounted bacterial virulence factors may contribute to the colonization of cattle. The objective of the present study was to examine the impact of lineage type, cytotoxin activity, and cytotoxin expression on the amount of E. coli O157:H7 colonization of cattle tissue and cells in vitro. Using selected bovine- and human-origin strains, we determined that lineage type predicted the amount of E. coli O157:H7 strain colonization: lineage I > intermediate lineages > lineage II. All E. coli O157:H7 strain colonization was dose dependent, with threshold colonization at 103 to 105 CFU and maximum colonization at 107 CFU. We also determined that an as-yet-unknown factor of strain origin was the most dominant predictor of the amount of strain colonization in vitro. The amount of E. coli O157:H7 colonization was also influenced by strain cytotoxin activity and the inclusion of cytotoxins from lineage I or intermediate lineage strains increased colonization of a lineage II strain. There was a higher level of expression of the Shiga toxin 1 gene (stx 1) in human-origin strains than in bovine-origin strains. In addition, lineage I strains expressed higher levels of the Shiga toxin 2 gene (stx 2). The present study supports a role for strain origin, lineage type, cytotoxin activity, and stx 2 expression in modulating the amount of E. coli O157:H7 colonization of cattle.

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Sensitivity of Shiga Toxin–Producing Escherichia coli, Multidrug-Resistant Salmonella, and Antibiotic-Susceptible Salmonella to Lactic Acid on Inoculated Beef Trimmings

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-128 ◽

2012 ◽

Vol 75 (10) ◽

pp. 1751-1758 ◽

Cited By ~ 11

Author(s):

ALIYAR FOULADKHAH ◽

IFIGENIA GEORNARAS ◽

HUA YANG ◽

KEITH E. BELK ◽

KENDRA K. NIGHTINGALE ◽

...

Keyword(s):

Escherichia Coli ◽

Lactic Acid ◽

Salmonella Typhimurium ◽

Shiga Toxin ◽

Multidrug Resistant ◽

Escherichia Coli O157 ◽

Acid Solutions ◽

E Coli ◽

Salmonella Newport ◽

Acid Treatments

Studies were performed to determine whether lactic acid treatments used to reduce Escherichia coli O157:H7 on beef trimmings are also effective in controlling non-O157 Shiga toxin–producing E. coli (nSTEC), and multidrug-resistant and antibiotic-susceptible Salmonella. Beef trimming pieces (10 by 5 by 1 cm) were inoculated (3 log CFU/cm2) separately with four-strain mixtures of rifampin-resistant E. coli O157:H7, O26, O45, O103, O111, O121, and O145. Similarly, in a second study, trimmings were separately inoculated with rifampin-resistant E. coli O157:H7, and antibiotic-susceptible or multidrug-resistant (MDR and/or MDR-AmpC) Salmonella Newport and Salmonella Typhimurium. Inoculated trimmings were left untreated (control) or were immersed for 30 s in 5% lactic acid solutions (25 or 55°C). No differences (P ≥ 0.05) were obtained among surviving counts of E. coli O157:H7 and those of the tested nSTEC serogroups on lactic acid–treated (25 or 55°C) samples. Counts (3.1 to 3.3 log CFU/cm2) of E. coli O157:H7 and nSTEC were reduced (P < 0.05) by 0.5 to 0.9 (25°C lactic acid) and 1.0 to 1.4 (55°C lactic acid) log CFU/cm2. Surviving counts of Salmonella on treated trimmings were not influenced by serotype or antibiotic resistance phenotype and were similar (P ≥ 0.05) or lower (P < 0.05) than surviving counts of E. coli O157:H7. Counts (3.0 to 3.3 log CFU/cm2) were reduced (P < 0.05) by 0.5 to 0.8 (E. coli O157:H7) and 1.3 to 1.5 (Salmonella) log CFU/cm2 after treatment of samples with 25°C lactic acid. Corresponding reductions following treatment with lactic acid at 55°C were 1.2 to 1.5 (E. coli O157:H7) and 1.6 to 1.9 (Salmonella) log CFU/cm2. Overall, the results indicated that lactic acid treatments used against E. coli O157:H7 on beef trimmings should be similarly or more effective against the six nSTEC serogroups and against multidrug-resistant and antibiotic-susceptible Salmonella Newport and Salmonella Typhimurium.

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