X-ray crystallography is extensively used to determine the atomic structure of proteins and their cofactors. Though a commonly overlooked problem, it has been shown that structural damage to a redox active metal site may precede loss of diffractivity by more than an order of magnitude in X-ray dose. Therefore the risk of misassigning redox states is great. Adequate treatment and consideration o...

The apparent proportion of column-chromatographically measured glycosylated hemoglobin in erythrocytes from an individual with hemoglobins A, S, and G was only 2.3% because the slow glycosylated variant hemoglobins were retarded in the column. In contrast, the value for glycosylated hemoglobin was 7.8% by a new cellulose acetate electrophoretic method that includes use of dextran sulfate buffer...

1. Distribution of zinc between the metalloprotein alpha 2-macroglobulin and albumin was determined in samples of serum obtained from twenty-three women in their third trimester of pregnancy and eighteen women who were not pregnant. 2. The decrease observed in total serum zinc in the group of pregnant women could be accounted for in large part by a decreased concentration of albumin-bound zinc....

We report the results of molecular dynamics simulations of electron-transfer activation parameters of plastocyanin metalloprotein involved as an electron carrier in natural photosynthesis. We have discovered that slow, non-ergodic conformational fluctuations of the protein, coupled to hydrating water, result in a very broad distribution of donor-acceptor energy gaps far exceeding those observed...

Molecular dynamics simulations have revealed a dramatic increase, with increasing temperature, of the amplitude of electrostatic fluctuations caused by water at the active site of metalloprotein plastocyanin. The increased breadth of electrostatic fluctuations, expressed in terms of the reorganization energy of changing the redox state of the protein, is related to the formation of the hydropho...