Proteinase activity of prevotella species associated with oral purulent infection

Area of Science:

• Oral Microbiology
• Bacterial Pathogenesis
• Enzymology

Background:

• Prevotella intermedia and Prevotella nigrescens are primary causes of acute dentoalveolar infections.
• Other Prevotella species are also implicated in these infections, necessitating further investigation into their roles.

Purpose of the Study:

• To investigate and compare the in vitro proteolytic activity of various Prevotella species associated with dentoalveolar infections.
• To determine if proteolytic activity differs between clinical isolates from infections and commensal strains from healthy individuals.

Main Methods:

• Collected 234 Prevotella strains from dentoalveolar infection pus and healthy volunteer plaque.
• Quantified in vitro proteolytic activity using a standard assay.
• Tested the effect of protease inhibitors N-ethylmaleimide and phenymethylsulfonyl fluoride.

Main Results:

• Prevotella intermedia and P. nigrescens exhibited significantly higher proteolytic activity than P. loescheii, P. oralis, P. melaninogenica, P. buccae, and P. denticola.
• Clinical strains of P. loescheii, P. melaninogenica, and P. intermedia showed significantly higher proteolytic activity than their commensal counterparts.
• Proteolytic activity across all tested Prevotella species was inhibited by N-ethylmaleimide and phenymethylsulfonyl fluoride, indicating cysteine and serine proteinase involvement.

Conclusions:

• Prevotella species linked to oral purulent infections produce cysteine and serine proteinases.
• Higher proteolytic activity in clinical Prevotella strains compared to commensal strains may contribute to their pathogenic potential in dentoalveolar infections.