Globulin molecular weight

Distribution. Lead in blood partitions between plasma and red blood cells, with the larger fraction (90-99%) associated with red blood cells (Cake et al. 1996 DeSilva 1981 Everson and Patterson 1980 Manton and Cook 1984 Ong and Lee 1980a). Lead in plasma binds to albumin and y -globulins (Ong and Lee 1980a). The fraction that is not bound to protein exists largely as complexes with low molecular weight sulfhydryl compounds these may include cysteine, homocysteine, and cysteamine (Al-Modhefer et al. 1991). Approximately 75% was bound to protein when whole human blood was incubated with 50 ig/dL lead (as lead chloride) approximately 90% of the bound lead was associated with albumin (Ong and Lee 1980a). However, the fraction of lead in plasma bound to protein would be expected to vary with the plasma lead concentration. 

The urine frequently contains casts and amorphous debris, but rarely any considerable number of red blood corpuscles. Proteinuria and aminoaciduria are found in nearly all untreated patients from a very early age. The proteinuria is usually reported as albuminuria in the literature, but in some cases the urinary protein has been shown by electrophoresis to consist largely of a-globulin and other relatively low-molecular-weight proteins (B21). A similar urinary pattern occurs in a number of diseases of the renal tubule. The proteinuria is often only moderate in degree, e.g., < 50 to 150 mg protein per 100 ml of urine, but is easily detected by the conventional tests for protein, such as salicylsulfonic acid. Excretion of protein can rise to nearly 1 g/100 ml in some cases (H8, L7). 

A later study (45) indicates that cucurbitin from pumpkin has a molecular weight of TT2,000 dal tons that can be electrophoretically separated into subunits of 63,000 and 56,000 dal tons. Reduction of disulfides produces polypeptides of 36,000 and 22,000 dal tons. Globulins from six cucurbits examined chromatographically (46) have molecular weights of 220,000 to 260,000 dal tons that exhibit predominantly 10.4 - 11.2 S values (about 95% of the three globulin fractions). Cucurbitin from Cucumis sativus appears a tetramer of... 

Early ultracentrifuges were extremely expensive and were therefore located in only a small number of laboratories. Nevertheless, rapid strides were made in the theory and practice of ultracentrifugation. By 1940 the behavior of proteins with molecular weights ranging from that of cytochrome c (13.4 kDa) to serum globulin (ca.170 kDa) had been studied. 

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