Haemoglobin degradation

O9 generation (after binding to haem from proteolytically degraded haemoglobin) [antimalarial] 500 million have malaria... 

The presence of a yellow colour in cerebrospinal fluid. It can be due to degraded haemoglobin after a cerebral haemorrhage or can occur as a result of jaundice. 

Haemoglobin, described in Section 5.3.1.3, is the most well known but it is just one of a number of carrier proteins present in blood. Albumin is quantitatively the most abundant protein in plasma. It is synthesized in the liver and circulates with a half life of about 3 weeks before being degraded or eliminated. Albumin has two very important functions to fulfil. First, it makes a significant contribution to the oncotic pressure of the blood and so influences the distribution of fluid between the intracellular and... 

The synthesis of haemoglobin in the bone marrow requires about 20-25 mg of iron each day. This is obtained either from the diet or from the iron that is recycled from the degradation of senescent erythrocytes (they survive for only about 120 days) which are phagocytosed by macrophages in the liver and spleen. The iron released from the... 

It probably influences haemoglobin degradation by parasitic lysosomes by raising intravesicular pH in malarial parasite cells. It also interferes with synthesis of nucleoproteins by the parasite. 

When the red blood cells die after their average lifetime of some 120 days, their haemoglobin is degraded to bilirubin which is then filtered by the liver. In new-born infants this process cannot take place often for several days, while the liver becomes fully functional. The accumulation of bilirubin in the... 

Proteases have played a pivotal role in the development of parasitism. By the time flat-worms had emerged, members of all the major families of proteases had evolved such that parasites exhibit a complete profile of exo- and endoproteases. The best characterized of these proteases, including cathepsins B, L, C, D and LAP, are vital in the complex process of nutrient uptake from the host by sequentially degrading blood tissue proteins such as haemoglobin to free amino acids. However, other proteases are involved in separate essen-... 

Becker, M.M., Harrop, S.A., Dalton, J.P., Kalinna, B.H., McManus, D.P. and Brindley, P.J. (1995) Cloning and characterization of the Schistosoma japonicum aspartic proteinase involved in haemoglobin degradation. Journal of Biological Chemistry 270, 24496-24501. 

Brinkworth, R.I., Prociv, P., Loukas, A. and Brindley, P.J. (2001) Haemoglobin-degrading, aspartic protease of blood-feeding parasites substrate specificity revealed by homology models. The Journal of Biological Chemistry 276, 38844-38851. 

Wasilewski, M.M., Lim, K.C., Phillips, J. and McKerrow, J.H. (1996) Cysteine protease inhibitors block schistosome haemoglobin degradation in vitro and decrease worm burden and egg production in vivo. Molecular and Biochemical Parasitology 81, 1 79-1 89. 

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