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Profiling of Permethylated Mucin O-glycans Using Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry
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Formation of methyl mercaptan from L-methionine by Porphyromonas gingivalis

M Yoshimura1, Y Nakano, Y Yamashita

  • 1Department of Preventive Dentistry, Kyushu University Faculty of Dental Science, Fukuoka 812-8582, Japan.

Infection and Immunity
|November 18, 2000
PubMed

Insights

Oral bacteria like Porphyromonas gingivalis produce methyl mercaptan, a cause of bad breath. This study shows methyl mercaptan also contributes to P. gingivalis pathogenicity, impacting virulence.

Area of Science:

  • Microbiology
  • Oral Health
  • Biochemistry

Background:

  • Methyl mercaptan (CH3SH) production by oral bacteria is a primary cause of oral malodor.
  • Periodontopathic bacteria, such as Porphyromonas gingivalis, are implicated in severe oral conditions.

Purpose of the Study:

  • To investigate the role of Porphyromonas gingivalis in methyl mercaptan production from L-methionine.
  • To determine the contribution of methyl mercaptan to the pathogenicity of P. gingivalis.

Main Methods:

  • Cloning and sequencing of the mgl gene encoding L-methionine-alpha-deamino-gamma-mercaptomethane-lyase (METase) in P. gingivalis W83.
  • Construction of a METase-deficient mutant (M1217) of P. gingivalis W83.
  • Comparison of methionine degradation activity and virulence in mice between the mutant and wild-type strains.

Main Results:

  • P. gingivalis strains W83 and W50 produced significant amounts of methyl mercaptan from L-methionine.
  • The mgl gene consists of 1,200 bp, encoding a 43.3-kDa METase protein.
  • The METase-deficient mutant M1217 exhibited reduced methyl mercaptan production and decreased virulence compared to the wild-type W83.

Conclusions:

  • Methyl mercaptan production by P. gingivalis contributes to oral malodor.
  • Methyl mercaptan plays a role in the pathogenicity of P. gingivalis, influencing its virulence.

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