Studies on Soluble Fibrin in Plasma: I a. N-Terminal Analysis of a Modified Fraction I (Cohn) from Plasma Containing Fibrinolytic Inhibitors, and Incubated with Plasminogen-Free Human Thrombin

Abstract

Fresh human plasma containing fibrinolytic inhibitors was incubated with traces of plasminogen-free human thrombin. Subsequently, the clottable proteins were precipitated with either 16 or 8% ethanol. N-terminal analysis demonstrated that these proteins contained more N-terminal glycine (indicating soluble fibrin) when precipitated with 16 than with 8% ethanol. This probably indicates that the presence of more than one type of soluble fibrin in thrombin-incubated plasma is not due to plasmin activity in vitro.

Key Words:

• Blood coagulation
• fibrin
• fibrinogen
• plasma proteins
• plasmin
• N-terminal analysis
• thrombin