Limits...
Heat-Denatured Lysozyme Inactivates Murine Norovirus as a Surrogate Human Norovirus.

Takahashi H, Nakazawa M, Ohshima C, Sato M, Tsuchiya T, Takeuchi A, Kunou M, Kuda T, Kimura B - Sci Rep (2015)

Bottom Line: Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent.We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus.The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4 -5-7, Konan, Minato-ku, Tokyo, 108-8477 Japan.

ABSTRACT
Human norovirus infects humans through the consumption of contaminated food, contact with the excrement or vomit of an infected person, and through airborne droplets that scatter the virus through the air. Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent. In this study, we have discovered the thermal denaturing capacity of a lysozyme with known antimicrobial activity against gram-positive bacteria, as well as its inactivating effect on murine norovirus. This study is the first report on the norovirus-inactivating effects of a thermally denatured lysozyme. We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus. Transmission electron microscope analysis showed that virus particles exposed to thermally denatured lysozymes were expanded, compared to the virus before exposure. The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect. These results suggest that thermal denaturation of the lysozyme changes the protein structure, activating the region responsible for imparting an inactivating effect against the virus.

No MeSH data available.


Related in: MedlinePlus

Relationship between the thermal denaturation temperature for lysozyme solution and the MNV-1 inactivation effect.Significant differences were observed between 100 °C for 40 min and 90 °C for 40 min(p < 0.01) and between 100 °C for 40 min and 100 °C for 30 min(p < 0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4488868&req=5

f1: Relationship between the thermal denaturation temperature for lysozyme solution and the MNV-1 inactivation effect.Significant differences were observed between 100 °C for 40 min and 90 °C for 40 min(p < 0.01) and between 100 °C for 40 min and 100 °C for 30 min(p < 0.05).

Mentions: We first studied the relationship between the thermal denaturation temperature for the lysozyme and the inactivating effect against MNV (Fig. 1). The lysozyme solution was observed to inactivate MNV by 2 log or more when heated for 15 min or longer at 80 °C and 90 °C. Lysozyme solutions denatured at 100 °C for 10 min or more were observed to inactivate at least 2 log of MNV. In lysozymes heated to 90 °C and higher, we observed a stronger inactivation effect with a longer heating time; MNV was reduced by 4.5 log by the lysozyme solution treated for 40 min at 100 °C.


Heat-Denatured Lysozyme Inactivates Murine Norovirus as a Surrogate Human Norovirus.

Takahashi H, Nakazawa M, Ohshima C, Sato M, Tsuchiya T, Takeuchi A, Kunou M, Kuda T, Kimura B - Sci Rep (2015)

Relationship between the thermal denaturation temperature for lysozyme solution and the MNV-1 inactivation effect.Significant differences were observed between 100 °C for 40 min and 90 °C for 40 min(p < 0.01) and between 100 °C for 40 min and 100 °C for 30 min(p < 0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4488868&req=5

f1: Relationship between the thermal denaturation temperature for lysozyme solution and the MNV-1 inactivation effect.Significant differences were observed between 100 °C for 40 min and 90 °C for 40 min(p < 0.01) and between 100 °C for 40 min and 100 °C for 30 min(p < 0.05).
Mentions: We first studied the relationship between the thermal denaturation temperature for the lysozyme and the inactivating effect against MNV (Fig. 1). The lysozyme solution was observed to inactivate MNV by 2 log or more when heated for 15 min or longer at 80 °C and 90 °C. Lysozyme solutions denatured at 100 °C for 10 min or more were observed to inactivate at least 2 log of MNV. In lysozymes heated to 90 °C and higher, we observed a stronger inactivation effect with a longer heating time; MNV was reduced by 4.5 log by the lysozyme solution treated for 40 min at 100 °C.

Bottom Line: Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent.We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus.The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4 -5-7, Konan, Minato-ku, Tokyo, 108-8477 Japan.

ABSTRACT
Human norovirus infects humans through the consumption of contaminated food, contact with the excrement or vomit of an infected person, and through airborne droplets that scatter the virus through the air. Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent. In this study, we have discovered the thermal denaturing capacity of a lysozyme with known antimicrobial activity against gram-positive bacteria, as well as its inactivating effect on murine norovirus. This study is the first report on the norovirus-inactivating effects of a thermally denatured lysozyme. We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus. Transmission electron microscope analysis showed that virus particles exposed to thermally denatured lysozymes were expanded, compared to the virus before exposure. The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect. These results suggest that thermal denaturation of the lysozyme changes the protein structure, activating the region responsible for imparting an inactivating effect against the virus.

No MeSH data available.


Related in: MedlinePlus