Description

A visible femtosecond laser is shown to be capable of selectively inactivating a wide spectrum of microorganisms in a wavelength and pulse width dependent manner. However, the mechanism of how a visible femtosecond laser affects the viability of different microorganisms

A visible femtosecond laser is shown to be capable of selectively inactivating a wide spectrum of microorganisms in a wavelength and pulse width dependent manner. However, the mechanism of how a visible femtosecond laser affects the viability of different microorganisms is still elusive. In this paper, the cellular surface properties, membrane integrity and metabolic rate of Escherichia coli (E. coli) irradiated by a visible femtosecond laser (λ = 415 nm, pulse width = 100 fs) with different exposure times were investigated. Our results showed that femtosecond laser treatment for 60 min led to cytoplasmic leakage, protein aggregation and alternation of the physical properties of the E. coli cell membrane. In comparison, a 10 min exposure of bacteria to femtosecond laser irradiation induced an immediate reduction of 75% in the glucose-dependent respiratory rate, while the cytoplasmic leakage was not detected. Results from enzymatic assays showed that oxidases and dehydrogenases involved in the E. coli respiratory chain exhibited divergent susceptibility after laser irradiation. This early commencement of respiratory inhibition after a short irradiation is presumed to have a dominant effect on the early stage of bacteria inactivation.

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Title
  • Inhibition of Escherichia Coli Respiratory Enzymes by Short Visible Femtosecond Laser Irradiation
Contributors
Date Created
2014-08-06
Resource Type
  • Text
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    Identifier
    • Digital object identifier: 10.1088/0022-3727/47/31/315402
    • Identifier Type
      International standard serial number
      Identifier Value
      0022-3727
    • Identifier Type
      International standard serial number
      Identifier Value
      1361-6463
    Note
    • Copyright IOP Publishing. This is the authors' final, peer-reviewed manuscript. The final version as published can be viewed online at http://dx.doi.org/10.1088/0022-3727/47/31/315402

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    This is a suggested citation. Consult the appropriate style guide for specific citation guidelines.

    Lu, Chieh-Han, Lin, Kung-Hsuan, Hsu, Yung-Yuan, Tsen, Kong-Thon, & Kuan, Yung-Shu (2014). Inhibition of Escherichia coli respiratory enzymes by short visible femtosecond laser irradiation. JOURNAL OF PHYSICS D-APPLIED PHYSICS, 47(31), 315402. http://dx.doi.org/10.1088/0022-3727/47/31/315402

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