T: tense state, circle, less active, R: relaxed state, square, more active Ancertea, allAgr-none Sequential 8=日888一一 ① 二匹L二L 11111 ① 一岀觀一→乩一比一 (b)
T: tense state, circle, less active; R: relaxed state, square, more active Concerted, all-or-none Sequential
1.5.5 The functional characteristics of an allosteric protein are regulated by specific molecules in its environment. In another words, in the evolutionary transition from myoglobin to hemglobin, a macromolecule capable of perceiving information from its environment has emerged
1.5.5 The functional characteristics of an allosteric protein are regulated by specific molecules in its environment. In another words, in the evolutionary transition from myoglobin to hemglobin, a macromolecule capable of perceiving information from its environment has emerged
1.6 Sickle-cell anemia was found to be caused by a single amino acid change in the b chain of hemoglobin molecules 1.6.1 The hemoglobin molecule from sickle-cell anemia patients(Hbs) was fou d to have a higher pl value(having more net positive charges 1.6.2 Peptide fingerprinting(protease digestion electrophoresis chromatography) of Hbs and hba(wt) revealed that all but one of the peptide spots matched. 1.6.3 Amino acid sequencing revealed that hbs contains Val instead of Glu is at position 6 of the p chain 1.6.4 The oxygen binding affinity and allosteric properties of hemoglobin are virtually unaffected by this change(the B6 is located at the surface of the protein)
1.6 Sickle-cell anemia was found to be caused by a single amino acid change in the b chain of hemoglobin molecules. 1.6.1 The hemoglobin molecule from sickle-cell anemia patients (HbS) was found to have a higher pI value (having more net positive charges). 1.6.2 Peptide fingerprinting (protease digestion + electrophoresis + chromatography) of HbS and HbA (wt) revealed that all but one of the peptide spots matched. 1.6.3 Amino acid sequencing revealed that HbS contains Val instead of Glu is at position 6 of the b chain! 1.6.4 The oxygen binding affinity and allosteric properties of hemoglobin are virtually unaffected by this change (the b6 is located at the surface of the protein)
1.6.5 High concentration of deoxygenated Hbs orms fiber participatates, which sickles the red blood cells, because the fiber formation is a highly concerted reaction 1.6.6 Presence of Val6 on the p subunits generates a hydrophobic patch on the surface which complements with another hydrophobic patch formed only in deoxygenated Hbs, thus generating the fiber precipitates (a polymer of Hbs). 1.6. 7 Sickle cell trait(heterozygote)confers a small but highly significant degree of protection against the most lethal form of malaria(probably by accelerating the destruction of infected erythrocytes, in Africa) 1.6.8 Fetal DNA can be analyzed for the presence of the hbs gene(prenatal dna diagnosis)
1.6.5 High concentration of deoxygenated HbS forms fiber participatates, which sickles the red blood cells, because the fiber formation is a highly concerted reaction. 1.6.6 Presence of Val6 on the b subunits generates a hydrophobic patch on the surface which complements with another hydrophobic patch formed only in deoxygenated HbS, thus generating the fiber precipitates (a polymer of HbS). 1.6.7 Sickle cell trait (heterozygote) confers a small but highly significant degree of protection against the most lethal form of malaria (probably by accelerating the destruction of infected erythrocytes, in Africa). 1.6.8 Fetal DNA can be analyzed for the presence of the HbS gene (prenatal DNA diagnosis)
1.7 Thalassemias are genetic disorders characterized by defective synthesis of one or more hemoglobin chains 1.7.1 This can be caused by a missing gene, impaired RNa synthesis or processing, generation of grossly abnormal proteins
1.7 Thalassemias are genetic disorders characterized by defective synthesis of one or more hemoglobin chains. 1.7.1 This can be caused by a missing gene, impaired RNA synthesis or processing, generation of grossly abnormal proteins