magnetite (fe3o4) nanoparticles have been successfully prepared by a novel one-step and surfactant-free approach utilizing ferrous ion, as a single iron source. in this manner, the reaction occurs between two aqueous solutions via the spontaneous transfer of ammonia gas from one to another in room temperature. no ferric source or oxidizing specie, oxidation controlling and capping agents are ne...

High-valent iron species are powerful oxidizing agents in chemical and biological catalysis. The best characterized form of an Fe(V) equivalent described in biological systems is the combination of a b-type heme with Fe(IV)=O and a porphyrin or amino acid cation radical (termed Compound I). This work describes an alternative natural mechanism to store two oxidizing equivalents above the ferric ...

Flavin-containing monooxygenase from yeast (yFMO) carries out the O(2)- and NADPH-dependent oxidation of biological thiols, including oxidizing glutathione to glutathione disulfide. FMO provides a large fraction of the oxidizing necessary for proper folding of disulfide bond-containing proteins; deletion of the enzyme reduces proper folding of endogenous carboxypeptidase Y by about 40%. The enz...

The NMDA receptor is the subject of intense study due to its critical role in many neuronal processes and neuropathologies. This receptor is modulated by a wide variety of endogenous and exogenous agents, including reducing and oxidizing (redox) agents. Despite a wealth of physiological information, details of the structural basis of modulation are only beginning to emerge. It has been proposed...

The functional significance of the oxidation/reduction state of sulfhydryl groups of cGMP-dependent protein kinase (cGMP kinase) was studied at 30 degrees C using different metal ions as oxidizing agents. Mn2+, Zn2+, Fe2+, Ni2+, and Co2+ failed to activate cGMP kinase, whereas Cu2+, Cu+, Fe3+, Hg2+, and Ag+ activated cGMP kinase by oxidation with an activity ratio (-cGMP/+cGMP) of about 0.7. Th...

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...

HE ESTABLISHMENT AND ACCEPTANCE of an analytic procedure as a method to be relied upon with complete confidence demands: (1) 8pecific’tty of the method, i.e. minimal interference by other compounds; (2) quantitative recovery of the specific substance when it is added to the medium in which it is usually determined; and (3) reproducibility of results within reasonable limits on replicate samples...

Although it is common practice to use hematoxylin as the source of dye, it is not itself the actual dye and it has to be oxidized to hematein, which is a dye, before it can be used. This process is called ripening, and can be accomplished in two distinct ways. The ripening is usually accomplished with chemical oxidizing agents, but is sometimes accomplished by atmospheric oxygen over time. Hema...

Lipases are the enzymes of choice for laundry detergent industries owing to their triglyceride removing ability from the soiled fabric which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In the present study, a partially purified bacterial lipase from Staphylococcus arlettae JPBW-1 isolated from the rock salt mine has been assessed for its trig...