Hemoglobin molecular weight

Under physiological conditions, transfer of Et3PAufrom hemoglobin to albumin has been observed. The transfer is direct and does not require a low-molecular weight thiol such as GSH as an intermediary and indicates that inter-protein transfer of gold can occur spontaneously. The rapid and efficient manner of establishing this equilibrium (for transauration ) could determine many ofthe effects of intracellular and extracellular chemistry of gold. 

Kofinas et al. (1996) have prepared PEO hydrogels by a similar technique. In this work, they studied the diffusional behavior of two macromolecules, cytochrome C and hemoglobin, in these gels. They noted an interesting, yet previously unreported dependence between the crosslink density and protein diffusion coefficient and the initial molecular weight of the linear PEGs. 

To get from the amino acid analysis of the protein to its structure, its molecular weight had to be estimated. As early as 1885 Zinoffsky had reported a minimum molecular weight for hemoglobin of 16.73 kDa based on its elementary composition and assuming one atom of iron/ mole, a remarkably accurate figure. For most proteins because of their large size and ease of denaturation, classical cryoscopic or ebulliscopic methods were impracticable. Osmotic pressure measurements were... 

Based on the magnitude of diffusion constants for globular (i.e., spherical) protein molecules, one can estimate that proteins like hemoglobin (mass = 68 kDa diffusivity = 6.2 m /s X 10 ) can readily diffuse 20-30 micrometers within 10-20 seconds. By contrast, low-molecular-weight metabolites, such as glycine (mass = 75 diffusivity = 95 m /s X 10 ) and arginine (mass = 174 diffusivity = 58 m /s X 10 ), will rapidly traverse these distances in a few seconds or less. 

Large molecular weight proteins (catalase, /1-galac-tosidase, BSA, hemoglobin) AOT/isooctane Extraction and purification [99]... 

WOF is a problem associated with the use of precooked meat products such as roasts and steaks. The term WOF was first used by Tims and Watts (2) to describe the rapid development of oxidized flavors in refiigerated cooked meats. Published evidence indicates that the predominant oxidation catalyst is iron from ntyoglobin and hemoglobin, which becomes available following heat denaturation of the protein moiety of these complexes. The oxidation of the lipids results in the formation of low molecular weight components such as aldehydes, adds, ketones and hydrocarbons which may contribute to undesirable flavor. 

The metalloporphyrin complexes and their derivatives have been studied from the standpoint of model compounds of hemoglobin. The polymer-metalloporphyrin complexes are also formed by the reaction in Scheme 8, and a few qualitative investigations have been made with poly(L-lysine)9,10, poly(L-histidine)11, and poly(vinylimidazole)12 as the polymer ligand. Blauer9 has studied the complex formation of heme with poly(L-lysine) and has discussed the effects of the molecular weight and secondary structure of poly(L-lysine) on complex formation. 

Hemoglobin, a protein with a molecular weight of 68 000 Da, consists of four subunits with a molecular weight of 17 000 Da. Oxygenation proceeds in the following four steps ... 

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