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Magnesium Hydroxide Nanoparticles Kill Exponentially Growing and Persister Escherichia coli Cells by Causing Physical Damage.

ABSTRACT: Magnesium hydroxide nanoparticles are widely used in medicinal and hygiene products because of their low toxicity, environment-friendliness, and low cost. Here, we studied the effects of three different sizes of magnesium hydroxide nanoparticles on antibacterial activity: NM80, NM300, and NM700. NM80 (D50 = 75.2 nm) showed a higher bactericidal effect against Escherichia coli than larger nanoparticles (D50 = 328 nm (NM300) or 726 nm (NM700)). Moreover, NM80 showed a high bactericidal effect against not only exponential cells but also persister cells, which are difficult to eliminate owing to their high tolerance to antibiotics. NM80 eliminated strains in which magnesium-transport genes were knocked out and exhibited a bactericidal effect similar to that observed in the wild-type strain. The bactericidal action involved physical cell damage, as confirmed using scanning electron microscopy, which showed that E. coli cells treated with NM80 were directly injured.

SUBMITTER: Nakamura Y

PROVIDER: S-EPMC8234494 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Magnesium Hydroxide Nanoparticles Kill Exponentially Growing and Persister Escherichia coli Cells by Causing Physical Damage.

Nakamura Yohei Y Okita Kaede K Kudo Daisuke D Phuong Dao Nguyen Duy DND Iwamoto Yoshihito Y Yoshioka Yoshie Y Ariyoshi Wataru W Yamasaki Ryota R

Nanomaterials (Basel, Switzerland) 20210616 6

Magnesium hydroxide nanoparticles are widely used in medicinal and hygiene products because of their low toxicity, environment-friendliness, and low cost. Here, we studied the effects of three different sizes of magnesium hydroxide nanoparticles on antibacterial activity: NM80, NM300, and NM700. NM80 (D50 = 75.2 nm) showed a higher bactericidal effect against Escherichia coli than larger nanoparticles (D50 = 328 nm (NM300) or 726 nm (NM700)). Moreover, NM80 showed a ...[more]

PMID: 34208716

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Dataset Information

Magnesium Hydroxide Nanoparticles Kill Exponentially Growing and Persister Escherichia coli Cells by Causing Physical Damage.

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Magnesium Hydroxide Nanoparticles Kill Exponentially Growing and Persister <i>Escherichia coli</i> Cells by Causing Physical Damage.

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