Fibrinogen is converted into fibrin.

. NameThe essence of blood clotting is the production of fibrin gels, which are fibrinogens in plasma that are reduced in coagulation enzymes to fibrin and polymerized into insoluble mesh structures.fibrinogen molecules consist of two pairs of α chains, β-chains and γ-chains, each of the three peptide chains (α, β, γ) stranded synthesis rope-like, forming two rope-like peptide chains, at the end of N there are two sulfur bonds to stabilize the state molecules. α N-β of the chain of 16 and 14
amino acids
respectively, called fibro peptides A and B. Therefore, fibrinogen can be written (A alphaB beta) 2 (Figure 10-8).Figure 10-8 Cellulose Original Molecular Map The upper half is the molecular shape under the electroscope 6
peptide
chains, one is a double sulfur bond, the coagulase action pointFigure 10-9 cellulose protein gel productioncoagulase is essentially a proteolytic enzyme, can be specific to acting on A alpha and B chain of sterine. Cut A, B fiber peptides. Because fiber peptides A and B are acidic peptides with more negative charge. Because of charge rejection, the polymerization between fibrinogens is hindered. After the removal of fiber peptides A and B into fibrin negative reduction, while exposing complementary binding points, conducive to automatic polymerization, fibrin units through edge-by-side, end-to-end polymerization to form a polymerization chain. This polymer instability is called soft clots. It then forms a firm net through the role of the factor XIII.a. The factor XIII.a is a transpeptide enzyme that catalyzes a co-priced binding between the glutamate residue γ-pyrethroid of one monoglyceride and the amino of the lysine residue of another monosome, during which NH3 is released (Figure 10-9, 10). Therefore, the factor XIII.a is called fibrin stabilization factor (fibrin stabilizingfactor, FSF). Factor XIII. Present in plateplates and plasma, activated as XIII.a after the coagulase removes part of the peptide segment.resulting stable fibrin networks are different from soft coagulation blocks, which are insoluble in 5M of pyrethrin and 1% chloroacetic acid solution. This mesh structure contracts under the action of thrombosis proteins on plate plate plates, so that the edges of the wound are close to each other and the wound is easily closed. The surface of fibroblasts is covered with a fibrin-like
protein
, called adhesion protein, which is networked with fibrin by XII.a catalysis. and fix the fibrin. Therefore, the factor XII.a is also directly involved in wound healing.10-10 factor XIII.a action

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