Passage
Hemophilia B is a blood clotting disorder caused by a factor IX (FIX) deficiency. FIX is a 57-kDa, vitamin K-dependent protease that activates factor X, leading to the conversion of prothrombin to thrombin for propagation of the clotting cascade. Activated FIX has two major domains: a γ-carboxyglutamic acid domain and a serine protease domain. The γ-carboxyglutamic acid domain participates in the oxidation of vitamin K using metallic cofactors, as shown in Figure 1.
Figure 1 Oxidation of vitamin KTo further analyze the γ-carboxyglutamic acid-rich domain of FIX, an analogous synthetic peptide composed of matching residues 1 through 49 on FIX was evaluated by proton nuclear magnetic resonance (NMR) spectroscopy. Analysis of the proton chemical shift before the addition of metal ions suggested that the synthetic peptide contained normal structural elements. Large chemical shifts were observed after the addition of calcium and beryllium, as shown in Figure 2.
Figure 2 Results of NMR spectroscopy (tetramethylsilane [TMS] peak has been removed) The synthetic analog was then placed in solution with vitamin K hydroquinone and cofactors required for vitamin K oxidation. The oxidation products of vitamin K in Reactions 1 and 2 were collected and evaluated under high-performance liquid chromatography (HPLC) using hexane as the mobile phase. Analysis demonstrated cis and trans isomers of vitamin K₁ and a trans-epoxy vitamin K₁, as shown in Figure 3.
Figure 3 Results of HPLC separation
Adapted from Freedman SJ, Furie BC, Furie B, Baleja JD. Structure of the metal-free gamma-carboxyglutamic acid-rich membrane binding region of factor IX by two-dimensional NMR spectroscopy. J Biol Chem. 1995.
-The addition of metallic ions to FIX causes a conformational change that leads to induction of FIX activity, as shown in Figure 2. The 1 ppm (parts per million) proton peak in the inactivated FIX most likely represents:

Question

Passage
Hemophilia B is a blood clotting disorder caused by a factor IX (FIX) deficiency. FIX is a 57-kDa, vitamin K-dependent protease that activates factor X, leading to the conversion of prothrombin to thrombin for propagation of the clotting cascade. Activated FIX has two major domains: a γ-carboxyglutamic acid domain and a serine protease domain. The γ-carboxyglutamic acid domain participates in the oxidation of vitamin K using metallic cofactors, as shown in Figure 1.

Figure 1 Oxidation of vitamin KTo further analyze the γ-carboxyglutamic acid-rich domain of FIX, an analogous synthetic peptide composed of matching residues 1 through 49 on FIX was evaluated by proton nuclear magnetic resonance (NMR) spectroscopy. Analysis of the proton chemical shift before the addition of metal ions suggested that the synthetic peptide contained normal structural elements. Large chemical shifts were observed after the addition of calcium and beryllium, as shown in Figure 2.

Figure 2 Results of NMR spectroscopy (tetramethylsilane [TMS] peak has been removed) The synthetic analog was then placed in solution with vitamin K hydroquinone and cofactors required for vitamin K oxidation. The oxidation products of vitamin K in Reactions 1 and 2 were collected and evaluated under high-performance liquid chromatography (HPLC) using hexane as the mobile phase. Analysis demonstrated cis and trans isomers of vitamin K₁ and a trans-epoxy vitamin K₁, as shown in Figure 3.

Figure 3 Results of HPLC separation
Adapted from Freedman SJ, Furie BC, Furie B, Baleja JD. Structure of the metal-free gamma-carboxyglutamic acid-rich membrane binding region of factor IX by two-dimensional NMR spectroscopy. J Biol Chem. 1995.
-The addition of metallic ions to FIX causes a conformational change that leads to induction of FIX activity, as shown in Figure 2. The 1 ppm (parts per million) proton peak in the inactivated FIX most likely represents:

Quizplus · Accepted Answer

The Answer is D

Passage Hemophilia B Is a Blood Clotting Disorder Caused by a a Factor