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Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 1,459 records · Page 81Linked to original sources
PubMed1975

Degradation of neocarzinostatin by blood sera in vitro and its inhibition by diisopropyl fluorophosphate and n-ethylmaleimide.

Inactivation of antitumor antibiotic, Neocarzinostatin, which occurs in vivo or during incubation with serum in a test tube, was found to depend on the dose of serum and incubation period. The inactivation process was accompanied with degradation of Neocarzinostatin to a smaller molecular size with concomitant loss in antigenic activities at a slower rate. Apparent increase, close to about 250% of control, in the antibiotic activity was found before the inactivation, in the presence of diisopropyl fluorophosphate, or about 200% in the presence of N-ethylmaleimide. The present findings suggest that the degradation process partly depends on proteolysis by serine type proteinase(s) and partly on the involvement of sulfhydryl groups. These results imply two possible applications; one for chemotherapy with Neocarzinostatin in combination with inhibitors of proteolysis and the other for drug design through the modification of amino acid residues on Neocarzinostatin molecules which provide the enzyme binding sites such as lysine and arginine for the proteolytic catalysis.

Antibiotics, Antineoplastic↗
PubMed1974

Preparation of succinyl neocarzinostatin.

All amino groups in a proteinous antitumor antibiotic, neocarzinostatin, were reacted with succinic anhydride yielding bis-N-succinyl neocarzinostatin which retained biological activity in vitro against human cell lines and a bacterium. Amino groups in neocarzinostatin do not appear to play an important role in the activity.

Antibiotics, Antineoplastic↗