Six pyridyl derivatives [benzylviologen, 2-anilinopyridine, l,2-bis(4-pyridyl)ethane, l,2-b is(4pyridyl)ethylene, 2-benzoylpyridine, and 2-benzylaminopyridine] and five heme-iron derivatives [hemoglobin, hemin, hem atin, ferritin, and ferrocene] were screened for their potential to coun­ teract paraquat (l,l'-dim ethyl-4,4'-bipyridinium ion) toxicity on pea (Pisum sativum L.) isolated chloropla...

The constitution of the enzyme catalase is similar to that of hemoglobin. The prosthetic group is a hematin (1) and combines with a specific protein to form the enzyme molecule. Spectroscopic evidence suggests a close relationship between the porphyrin-iron complex contained in the enzyme and protohematin, the prosthetic group of hemoglobin (1). In the enzyme, however, the iron is held in the t...

Cultivation of amebae of the axenic strain of Naegleria gruberi, NEG-M, was achieved in media consisting entirely of chemically defined components. A complete medium that contains 31 components allows growth with yields up to 5 x 10(6) amebae per ml. A minimal medium gives lower yields but defines 22 components that are essential for continuous cultivation: 11 amino acids, 6 vitamins, hematin, ...

Phenol derivative-containing adhesive hydrogels has been widely recognized as having potential for biomedical applications, but their conventional production methods, utilizing a moderate/strong base, alkaline buffers, the addition of oxidizing agents or the use of enzymes, require alternative approaches to improve their biocompatibility. In this study, we report a polymeric, enzyme-mimetic bio...

The method to be described for the determination of hemoglobin depends upon the comparison, in a calorimeter, of carbon monoxide hemoglobin solutions, one of which has a known hemoglobin content. Hoppe-Seyler (1) was the first to describe carbon monoxide hemoglobin and to make use of this stable combination for estimating the hemoglobin content of blood. He devised a “double pipette” for compar...