Hemoglobins amino acid content

The amino acid content and sequence varies widely from source to source and it is this variability that gives proteins unique structural configurations and conformations, and steric and electrical characteristics permitting them to literally be the "spice of life itself". For instance hemoglobin, with a minimum... 

Amino Acid Content of Horae Hemoglobin Assumed Molecvlar Weight 66,700... 

Amino Acid Content of Various Hemoglobins, Myoglobins, Erythrocruorins, and CMorocruorins (161, 164, 165)... 

Well-established differences between adult and foetal hemoglobins are reflected in significant differences of amino acid content. 

Brydon and Roberts- added hemolyzed blood to unhemolyzed plasma, analyzed the specimens for a variety of constituents and then compared the values with those in the unhemolyzed plasma (B28). The following procedures were considered unaffected by hemolysis (up to 1 g/100 ml hemoglobin) urea (diacetyl monoxime) carbon dioxide content (phe-nolphthalein complex) iron binding capacity cholesterol (ferric chloride) creatinine (alkaline picrate) uric acid (phosphotungstate reduction) alkaline phosphatase (4-nitrophenyl phosphate) 5 -nucleotidase (adenosine monophosphate-nickel) and tartrate-labile acid phosphatase (phenyl phosphate). In Table 2 are shown those assays where increases were observed. The hemolysis used in these studies was equivalent to that produced by the breakdown of about 15 X 10 erythrocytes. In the bromocresol green albumin method it has been reported that for every 100 mg of hemoglobin/100 ml serum, the apparent albumin concentration is increased by 100 mg/100 ml (D12). Hemolysis releases some amino acids, such as histidine, into the plasma (Alb). 

About two-thirds of the zinc in pLasma is loosely bound to albumin. Most of the remaining zinc is tightly bound to other plasma proteins. A small fraction (2-37o) of plasma zinc is weakly bound to amino adds. The amino acids that most avidly bind zinc are histidine and cysteine. Amino add-associated zinc enters the glomerular filtrate and thus is a source of the zinc ions destined for excretion in the urine Most of the filtered zinc is reabsorbed and is prevented from immediate excretion. The zinc in red blood cells is bound to car nic anhydrase. Carbonic anhydrase is present at a level about 0,1% that of hemoglobin in the red blood cell on a poweight basis. The zinc content of mitochondria is about 1 nmol/mg protein (Unk and Jagow, 1995). 

In the human body, protein and other nitrogen-containing compounds are continuously broken dovm and contribute to an amino acid/nitrogen pool from which precursors and amino acids are reused fo s)mthesize enzymes, hormones, lean tissue, immune function proteins, muscle mass, bone matrix, and other essential compounds (Institute of Medicine of fhe National Academies, 2005). Mainfenance of the protein content of cerfain fissues and organs, such as skin, brain, hearf, liver, and kidneys, is essenfial for survival. In chronic protein deficiency, lean tissue and muscle mass are sacrificed to provide amino acid precursors for synthesis of critical compoimds, such as insulin and hemoglobin (Hoffer, 1994). 

In a schematic elution pattern of some standard proteins, peroxidase was eluted first with saline, BSA came next with glycine buffer at pH 6.6 and hemoglobin and catalase were eluted at a pH of nearly 8.0. Aldolase, lysozyme, chymotrypsinogen A, malate dehydrogenase, and cytochrome c were not eluted under these conditions, but were eluted with 0.1% SDS. The adsorption order does not depend on the isoelectric point, the molecular mass, or the content of basic amino acids. However, adsorption may depend on the o -helix content, and the secondary structure of those proteins may be important. We have also reported on protein adsorption and separation on siliconized glass surfaces (30), and on the adsorption and separation of nucleic acids on those same surfaces (31-35). 

Havinga, E. 1953. Comparison of the phosphorus content, optical rotation, separation of hemes and globin, and terminal amino acid residues of normal adult human hemoglobin and sickle cell anemia hemoglobin. Proc. Natl. Acad. Set. U.S. 39, 59. 

The hemoglobin of cats is highly sensitive to auto-oxidation and Heinz body formation. This sensitivity is probably caused by different amino acid paUems or differences in the sulfliydiyl content of the hemoglobin. 

At high voltage electrophoresis it seems that erythropoietin has a lower content of peptides and amino-acids than hemoglobin (Fig. 4). 

In their second case, one which had previously responded well to both arsenic and liver, Cuthbertson and associates observed that on subcutaneous injection of the amino acids, the clinical condition of the patient became worse. However, after a transfusion, liver therapy produced favorable results. Although tryptophan and histidine produced an early small reticulocyte response in both cases, there was no appreciable increase in the hemoglobin or red cell levels. Thus, even though there are indications that they have some stimulating action on hematopoietic tissue, the results do not justify ascribing the activity of liver to its content of free tryptophane and histidine. Dominici and Penati (27) were also unable to confirm the favorable results of the French authors. 

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