Hydrodynamic and mass spectrometry analysis of nearly-intact human fibrinogen, chicken fibrinogen, and of a substantially monodisperse human fibrinogen fragment X.
The shape and solution properties of fibrinogen are affected by the location of the C-terminal portion of the Aalpha chains, which is presently still controversial. We have measured the hydrodynamic properties of a human fibrinogen fraction with these appendages mostly intact, of chicken fibrinogen, where they lack 11 characteristic 13-amino acids repeats, and of human fragment X, a plasmin early degradation product in which they have been removed. The human fibrinogen/fragment X samples were extensively characterized by SDS-PAGE/Western blotting and mass spectrometry, allowing their composition to be precisely determined. The solution properties of all samples were then investigated by analytical ultracentrifugation and size-exclusion HPLC coupled with multi-angle light scattering and differential pressure viscometry detectors. The measured parameters suggest that the extra repeats have little influence on the overall fibrinogen conformation, while a significant change is brought about by the removal of the C-terminal portion of the Aalpha chains beyond residue Aalpha200.
Biopolimeri e Proteomica, Istituto Nazionale per la Ricerca sul Cancro, Largo R. Benzi 10, Genoa, Italy. barbara.cardinali@istge.it
Barbara
B
Cardinali
Aldo
A
Profumo
Anna
A
Aprile
Olwyn
O
Byron
Gordon
G
Morris
Stephen E
SE
Harding
Walter F
WF
Stafford
Mattia
M
Rocco
D000818:Animals; D002645:Chickens; D005338:Fibrin Fibrinogen Degradation Products / Q000737:chemistry*; D005341:Fibrinolysin / Q000737:chemistry; D006801:Humans; D013058:Mass Spectrometry; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary / Q000502:physiology; D013045:Species Specificity
D005338:Fibrin Fibrinogen Degradation Products; C030568:fibrinogen fragment X; D005341:Fibrinolysin