ABSTRACT
By means of spectrophotometric assay we investigated interaction of the dye Congo red (CR) with fibrils of model proteins--hen egg white lysozyme, recombinant human beta2-microglobulin (b2M) and recombinant human transthyretin (TTR). The commercial dye sample was found to contain a significant amount of impurities. Methods for the dye purification are disclosed and CR molar extinction coefficient at 490 nm (ε490) was determined to be 3.3 x 10(4) M(-1) x cm(-1) at pH above 6.0. Formation of the CR-fibril complex results in changes in the dye visible absorption spectrum. According to the data on titration of fibril solutions with excess of the dye, CR binds to lysozyme fibrils at a ratio of about 5 molecules per protein monomer within fibril structure, to b2M fibrils--about 4 molecules per monomer, to TTR fibrils--about 4 molecules per subunit of the protein.
Subject(s)
Amyloid/chemistry , Congo Red/chemistry , Muramidase/chemistry , Tristetraprolin/chemistry , beta 2-Microglobulin/chemistry , Animals , Chick Embryo , Congo Red/metabolism , Extracellular Matrix/chemistry , Humans , Muramidase/metabolism , Prealbumin/chemistryABSTRACT
It is shown for the first time that the mammalian enzymes can cause the degradation of the C60 fullerene molecules. This biodegradation is caused by the action of а hypochlorite generated neutrophil enzyme myeloperoxidase of fullerene molecule and leads to the loss of the topology of the fullerene core.
