Inhibition of host cell catalase by Mycoplasma pneumoniae: a possible mechanism for cell injury.

AUTOR(ES)

Almagor, M

RESUMO

This study demonstrates that viable Mycoplasma pneumoniae cells inhibit catalase activity in several types of intact human cells as well as in solution. Human erythrocyte catalase was inhibited up to 72%, and the inhibition of catalase in human cultured skin fibroblasts, lung carcinoma epithelial cells, and ciliated epithelial cells from human nasal polyps ranged between 75 and 80%. UV light-killed mycoplasmas failed to inhibit catalase activity both in intact cells and in vitro. After M. pneumoniae infection of human cultured skin fibroblasts, the level of malonyldialdehyde, an indicator for membrane lipid peroxidation, was 3.5 times higher than in control fibroblasts. Virulent M. pneumoniae completely inhibited catalase activity in solution, whereas the nonvirulent strains had a lesser ability to inhibit catalase activity. These findings suggest that as a result of host cell catalase inhibition by M. pneumoniae, the toxicity of the hydrogen peroxide generated by the microorganism and the affected cell is enhanced, thereby inducing host cell damage.

Documentos Relacionados

• Role of superoxide anion in host cell injury induced by mycoplasma pneumoniae infection. A study in normal and trisomy 21 cells.
• Relation of Catalase to Substrate Utilization by Mycoplasma pneumoniae
• Inhibition of Mycoplasma pneumoniae by Actinomycin D
• Possible Influence of Antibiotic Therapy on Usefulness of Metabolic Inhibition Test for Diagnosis of Mycoplasma pneumoniae Infections
• Role of host cell metabolism in the pathogenesis of Mycoplasma pneumoniae infection.