Visvalingam J, Ells TC, Yang X. Impact of persistent and nonpersistent generic Escherichia coli and Salmonella sp. recovered from a beef packing plant on biofilm formation by
E. coli O157.
J Appl Microbiol 2017;
123:1512-1521. [PMID:
28944561 DOI:
10.1111/jam.13591]
[Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/09/2017] [Accepted: 09/20/2017] [Indexed: 01/12/2023]
Abstract
AIMS
To examine the influence of meat plant Escherichia coli and Salmonella sp. isolates on E. coli O157 biofilm formation.
METHODS AND RESULTS
Biofilm formation was quantified by crystal violet staining (A570 nm ) and viable cell numbers for up to 6 days at 15°C. All five persistent E. coli genotypes formed strong biofilms when cultured alone or co-cultured with E. coli O157, with A570 nm values reaching ≥4·8 at day 4, while only two of five nonpersistent genotypes formed such biofilms. For E. coli O157:H7 co-culture biofilms with E. coli genotypes 136 and 533, its numbers were ≥1·5 and ≥1 log CFU per peg lower than those observed for its mono-culture biofilm at days 2 and 4, respectively. The number of E. coli O157:NM in similar co-culture biofilms was 1 log CFU per peg lower than in its mono-culture biofilm at day 4 and 6, respectively. Salmonella sp. lowered the number of E. coli O157:NM by 0·5 log unit, once, at day 6.
CONCLUSION
Generic E. coli may outcompete E. coli O157 strains while establishing biofilms.
SIGNIFICANCE AND IMPACT OF THE STUDY
Findings advance knowledge regarding inter-strain competition for a similar ecological niche and may aid development of biocontrol strategies for E. coli O157 in food processing environments.
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