Specificity role of the streptokinase C-terminal domain in plasminogen activation.
Several pathogenic bacteria secrete plasminogen activator proteins. Streptokinase (SKe) produced by Streptococcus equisimilis and staphylokinase secreted from Staphylococcus aureus are human plasminogen activators and streptokinase (SKu), produced by Streptococcus uberis, is a bovine plasminogen activator. Thus, the fusion proteins among these activators can explain the function of each domain of SKe. Replacement of the SKalpha domain with staphylokinase donated the staphylokinase-like activation activity to SKe, and the SKbetagamma domain played a role of nonproteolytic activation of plasminogen. Recombinant SKu also activated human plasminogen by staphylokinase-like activation mode. Because SKu has homology with SKe, the bovine plasminogen activation activities of SKe fragments were checked. SKebetagamma among them had activation activity with bovine plasminogen. This means that the C-terminal domain (gamma-domain) of streptokinase determines plasminogen species necessary for activation and converses the ability of substrate recognition to human species.
Kim
Dong Min
DM
Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 305-701 Taejon, South Korea.
Lee
Sang Jun
SJ
Yoon
Suk Kwon
SK
Byun
Si Myung
SM
D000818:Animals; D002417:Cattle; D004926:Escherichia coli / Q000201:enzymology; D019143:Evolution, Molecular; D006801:Humans; D008666:Metalloendopeptidases / Q000378:metabolism; D010958:Plasminogen / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013045:Species Specificity; D013291:Streptococcus / Q000201:enzymology; D013300:Streptokinase / Q000737:chemistry* / Q000378:metabolism; D013379:Substrate Specificity; D013997:Time Factors
D011993:Recombinant Fusion Proteins; D010958:Plasminogen; D013300:Streptokinase; D008666:Metalloendopeptidases; C022653:auR protein, Staphylococcus aureus