PubMed Health⌕ Search

Biomedical subjects

R N Feinstein

Publications and source records attributed to R N Feinstein.

At least 37 records · Page 2Linked to original sources

Relationship of hydrogen peroxide production by Mycoplasma pulmonis to virulence for catalase-deficient mice.

Mycoplasma pulmonis, an etiological agent of murine pneumonia, produced about 0.065 mumoles of hydrogen peroxide (H(2)O(2)) per hr per 10(10) colony-forming units. When glucose was present at a concentration of 0.01 m, H(2)O(2) production was increased by 50%. To determine if H(2)O(2) production by M. pulmonis could be correlated with virulence, normal, acatalasemic, and acatalatic mice were infected with the organism. Three days after infection with M. pulmonis significantly more acatalatic mice had pneumonia than did normal or acatalasemic mice. The pneumonia in acatalatic mice was also more severe than in the other two groups. Five days after infection, pneumonia in the acatalatic mice was resolved, whereas normal mice were severely affected. The presence of pneumonia and the severity were correlated with the recovery of M. pulmonis from the lesions. In vitro studies of the effect of catalase on M. pulmonis showed that exogenously supplied catalase stimulated the growth of M. pulmonis at 37 C and prolonged its survival at 25 C. Hemolysis of sheep blood, guinea pig blood, rabbit blood, and normal and acatalasemic mouse blood by M. pulmonis was inversely related to the catalase activity of the erythrocytes. These findings suggest that H(2)O(2) secretion contributes to the virulence of M. pulmonis and to the death of the microorganism in the absence of host catalase.

Animals↗

Blood catalsase polymorphism: some immunological aspects.

The immunological properties of the erythrocyte catalase of mice-normal (wild type) strain, one lacking catalase (acatalasemic), and four with only slight catalase activity (hypocatalasemic strains)-have been investigated. Agardiffusion tests and antigen titration of red-cell lysates against rabbit antiserum to catalase from normal mouse blood showed that immunologically identical catalase protein was present in large amounts in the acatalasemic as well as in the hypocatalasemic mutant strains. Despite lack of catalatic activity, the erythrocytes lacking catalase as well as those with only a little catalase contain catalase protein that has been modified at the site of enzyme activity, although the antigenic determinants are identical with those of normal catalase protein. This mutation is purely structural, being characterized by modification of the enzyme active site but not of the antigenic site.

Animals↗