Phosphatase Activity in T-Mycoplasmas

Carboxypeptidase activity in human mycoplasmas.

Mycoplasma salivarium produced citrulline, ammonia, and ATP from N-benzoylglycyl-L-arginine. The activity was inhibited by EDTA and was therefore concluded to be due to an arginine-specific carboxypeptidase. The activity was also found to exist in M. orale, M. buccale, M. faucium, and M. hominis.

Serotypic heterogeneity in isolates of human genital T-mycoplasmas.

Serological typing of human genital T-mycoplasmas by a complement-dependent mycoplasmacidal test showed that some recent isolates had different serotypic behavior before and after purification, and that the widely distributed prototype strain T960 was composed of at least two different serotypes. These results indicate that T-mycoplasma isolates from human genital tracts are not serologically h...

Studies on T-strain mycoplasmas in nongonococcal urethritis.

SHP-1 phosphatase activity counteracts increased T cell receptor affinity.

Anti-self/tumor T cell function can be improved by increasing TCR-peptide MHC (pMHC) affinity within physiological limits, but paradoxically further increases (K(d) < 1 μM) lead to drastic functional declines. Using human CD8(+) T cells engineered with TCRs of incremental affinity for the tumor antigen HLA-A2/NY-ESO-1, we investigated the molecular mechanisms underlying this high-affinity-assoc...

Mycoplasmas in Tissue Culture

Mycoplasmas are frequently found as contaminants in tissue-cultured cells. Infections may be inapparent or cause severe cytopathic changes. The source of primary contaminations in most cases is probably the upper respiratory tract of man. The wide dissemination of infections in cultures most probably occurs as a result of aerosols set up during the processing of contaminated cultures. Mycoplasm...