Bio-enzymes for inhibition and elimination of Escherichia coli O157:H7 biofilm and their synergistic effect with sodium hypochlorite

• Published in: Scientific reports Vol. 9; no. 1; pp. 9920 - 10
• Main Authors: Lim, Eun Seob, Koo, Ok Kyung, Kim, Min-Jeong, Kim, Joo-Sung
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.07.2019; Nature Publishing Group
• Subjects: 14/19; 14/28; 14/34; 631/326/421; 631/326/46; Biodegradation; Biofilms; Biofilms - drug effects; Biofilms - growth & development; Cell number; Cellulase; Cellulase - metabolism; Cellulose; Deoxyribonuclease; Deoxyribonuclease I - metabolism; Drug Synergism; E coli; Endopeptidase K; Endopeptidase K - metabolism; Enzymes; Escherichia coli; Escherichia coli O157 - drug effects; Escherichia coli O157 - growth & development; Escherichia coli O157 - metabolism; Humanities and Social Sciences; Inactivation; multidisciplinary; Oxidants - pharmacology; Proteinase; Science; Science (multidisciplinary); Sodium; Sodium hypochlorite; Sodium Hypochlorite - pharmacology; Synergistic effect
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-46363-w

Escherichia coli O157:H7 is one of the most important pathogens worldwide. In this study, three different kinds of enzymes, DNase I, proteinase K and cellulase were evaluated for inhibitory or degrading activity against E. coli O157:H7 biofilm by targeting extracellular DNA, proteins, and cellulose, respectively. The cell number of biofilms formed under proteinase K resulted in a 2.43 log CFU/cm 2 reduction with an additional synergistic 3.72 log CFU/cm 2 reduction after NaClO post-treatment, while no significant reduction occurred with NaClO treatment alone. It suggests that protein degradation could be a good way to control the biofilm effectively. In preformed biofilms, all enzymes showed a significant reduction of 16.4–36.7% in biofilm matrix in 10-fold diluted media ( p  < 0.05). The sequential treatment with proteinase K, cellulase, and NaClO showed a significantly higher synergistic inactivation of 2.83 log CFU/cm 2 compared to 1.58 log CFU/cm 2 in the sequence of cellulase, proteinase K, and NaClO ( p  < 0.05). It suggests that the sequence of multiple enzymes can make a significant difference in the susceptibility of biofilms to NaClO. This study indicates that the combination of extracellular polymeric substance-degrading enzymes with NaClO could be useful for the efficient control of E. coli O157:H7 biofilms.